Finat Technical Handbook 6th Edition, 2001 u736w

Note from the editor Although the 24 FINAT Test Methods described in this publication have been prepared with the utmost care and accuracy, it should be noted that the safety, efficiency and performance of these test methods and associated procedures is the responsibility of the end-. FINAT cannot be held liable for any loss, damage or injury resulting from their application. Furthermore, the test methods and associated information do not in themselves imply any specification of performance relating to the materials under test. FINAT The Hague, May 2001

FINAT Technical Handbook 6th edition, 2001

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Preface to the sixth edition

As the Chairman of the FINAT Technical Committee, it is my pleasure to introduce the 6th edition of the FINAT Technical Handbook. Over the years, the FINAT Technical Handbook and the FINAT Test Methods that it contains have developed as the international reference standard for suppliers and s of self-adhesive materials. This edition incorporates four new test methods, FTM 7, FTM 22, FTM 23 and FTM 24 respectively for the measurement of silicone coat weight, advanced ink adhesion, die-strike test and mandrel hold test. In addition, all the test methods have been reviewed and along with the information sections updated. Section 13 has been added to offer guidelines for accelerated ageing tests. FINAT owes recognition to the of the FINAT Technical Committee, who were closely involved in the revision of the Test Methods and thus actively contributed to the committee’s main objective: to understand and promote the science and technology of self-adhesive labelling. Drawing its knowledge from a wide range of industry ’ interests, the FINAT Technical Committee provides an informed body of professional expertise focused on the processes and materials used in the manufacture of selfadhesive labelstock, their conversion and subsequent application. By monitoring developments, trends in technology, in changing market use, and environmental issues, it provides an ongoing source of technical data and expert opinion and encourages networking and improved technical understanding throughout our global hip.

Andrew Jack Chairman FINAT Technical Committee

Dow Corning Ltd. Barry, UK September 2001 Copyright © 2001 FINAT, The Hague, The Netherlands All rights reserved

FINAT Technical Handbook 6th edition, 2001

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Contents

Section 1

FINAT Test Methods

Section 2

Test Equipment

61

2.1 Standard FINAT Test Roller

61

2.2 Automatic Rolling Device

61

2.3 Sources of Test Equipment

61

Section 3

Recommended s in self-adhesive laminates for roll labels

68

Section 4

Processing recommendations

69

Section 5

Surfaces requiring caution

71

Section 6

Safety guide for s of self-adhesive label stock products

72

Section 7

Handling and storage of label stock

74

Section 8

Adhesion problems

75

Section 9

Removal of adhesives or adhesive labels

76

Section 10

Adhesives

78

Section 11

Unwind roll chart

81

Section 12

Communication of technical data between labelstock manufacturer and label printer

82

Section 13

Guidelines for accelerated ageing tests

84

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FINAT Technical Handbook 6th edition, 2001

Section 1

FINAT Test Methods for Self-adhesive Materials

FTM 1

Peel adhesion (180°) at 300mm per minute

6

FTM 2

Peel adhesion (90°) at 300mm per minute

8

FTM 3

Low speed release force

11

FTM 4

High speed release Force

13

FTM 5

Resistance to elevated temperatures

15

FTM 6

Resistance to ultra-violet light

16

FTM 7

Silicone Coat Weight

18

FTM 8

Resistance to shear from a standard surface

20

FTM 9

‘Loop’ tack measurement

22

FTM 10

Quality of silicone coated substrates for self-adhesive laminates: release force

25

FTM 11

Quality of silicone coated substrates for self-adhesive laminates: subsequent adhesion

27

FTM 12

Adhesive coat weight

30

FTM13

Low temperature adhesion

31

FTM14

Dimensional stability

34

FTM15

Surface tension of plastic films .

36

FTM16

Chemical resistance – Spot method

39

FTM17

Chemical resistance – Immersion method

40

FTM18

Dynamic shear

42

FTM19

Recycling compatibility of self-adhesive labels

45

FTM20

Fluorescence and whiteness

50

FTM21

Ink adhesion (basic)

53

FTM22

Ink adhesion (advanced)

55

FTM23

Die strike

57

FTM24

Mandrel hold

59

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FTM1

FINAT Test Method no. 1 Peel adhesion (180°) at 300mm per minute

Scope

This test method is designed to quantify the permanence of adhesion or peelability of self-adhesive pressure sensitive) materials.

Definition

Peel adhesion is defined as the force required to remove pressure sensitive coated material, which has been applied to a standard test plate under specified conditions from the plate at a specified angle and speed. Adhesion is measured 20 minutes and 24 hours after application, the latter being considered as the ultimate adhesion.

Test Equipment

A tensile tester or similar machine, capable of peeling a laminate through an angle of 180° with a jaw separation rate of 300mm per minute with an accuracy of 2%. Test plates made of float glass or similar plate glass (Kristallspiegelglas, verre glace). A standard FINAT test roller.

Test Pieces

These should be strips taken from a representative sample of material. The strips should be 25 mm wide and have a minimum length of 175 mm in the machine direction. The cuts should be clean and straight. At least three strips should be taken from each material sample.

Test Conditions

Temperature 23°C 2°C, 50 % RH 5% RH. The test sample or test strips should be conditioned for not less than 4 hours before testing.

180° v = 300 mm/min

Procedure

Remove the backing material from each strip and place the adhesive coated facing material, adhesive side down, on to a clean test plate using light finger pressure. Roll twice in each direction with the standard FINAT test roller at a speed of approximately 10 mm per second to obtain intimate between the adhesive mass and the surface. After applying the strips to the test plate, leave for a period of 20 minutes before testing. Repeat the procedure with a second set of strips and leave for a period of 24 hours before testing. Fix the test plate and strip in the machine so that the angle of peel is 180°. Set the machine at 300mm per minute jaw separation rate. Carry out the test taking at least five readings at 10 mm intervals from the centre section of each test strip. Average the five or more readings for each strip.

Results

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Peel adhesion (180°) is expressed as the average result for the strips tested in Newtons per 25mm width for either 20 minutes or 24 hours application time.

FINAT Technical Handbook 6th edition, 2001

Failure PS CF AT

PT

Notes

Description Code Clear - no visible stain on . Stain - discoloration of test area, but no tacky residue. Cohesive Failure - the adhesive film is split during the test, leaving residue of adhesive on both the and the front material. Adhesive Transfer - the adhesive separates cleanly from the front material, leaving adhesive film on the test . The approximate extent of transfer should be quoted as percentage Paper Tear - the adhesive force exceeds the strength of a paper facing material. The results quoted should be the maximum reached before the paper tears.

1. The test plates must be thoroughly cleaned so that no trace of adhesive, grease, silicone or moisture is left on the surface. The following solvents can be used to clean the test plates: – Diacetone alcohol non-residual, technical grade or better – Methyl Ethyl Ketone (MEK) – Acetone – Methanol 95 % – n-Heptane – Ethyl Acetate The cleaning material must be absorbent, e.g. surgical gauze, cotton wool or tissue. To be suitable, materials must be lint-free during use, absorbent, contain no additives that are soluble in the solvents listed above, and made exclusively from virgin materials. Dispense one of the solvents listed above on to the , wiping it to dryness with fresh absorbent cleaning material. Repeat for a total of three washes with the solvent. Final wipe shall be with MEK or acetone. Alternative methods which remove contamination properly can be adopted, e.g. ultrasonic cleaning. Prior to use, the cleaned plates should be left for 4 hours under standard test conditions. Care should be taken to handle clean plates by the edge only. 2. Alternative surfaces to plate glass can be used such as stainless steel or aluminium or polyester film, but this must be clearly stated alongside the results. 3. If adhesion values are required when paper tear has occurred, then this test can be conducted at lower jaw separation rates quoting the latter against the results. 4. Conversion 1kgf- = 9.81 N

Issued October 1985 Revised March 1999 Revised May 2001

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FTM 2

FINAT Test Method no. 2 Peel adhesion (90°) at 300mm per minute

Scope

This test method differs from FTM 1 in that it can allow the end to compare the repositionability of different laminates. Measuring peel adhesion at 90° normally gives a lower value than at 180° and allows values to be measured for materials normally giving paper tear.

Definition

Peel adhesion is defined as the force required to remove pressure sensitive coated material, which has been applied to a standard test plate under specified conditions, from the plate at a specified angle and speed. Adhesion is measured 20 minutes and 24 hours after application, the latter being considered as the ultimate adhesion .

Test Equipment

A tensile tester or similar machine capable of peeling a laminate through an angle of 90° with a jaw separation rate of 300mm per minute and an accuracy of 2%. The apparatus must be equipped in a manner which ensures that the test plate can move freely in a horizontal position when the pressure sensitive material is removed in order to maintain an angle of peel of 90°. Test plates made of float glass or similar plate glass (Kristallspiegelglas, verre glace). A standard FINAT test roller.

Test Pieces

These should be strips from a representative sample of material. The strips should be 25 mm wide and have a minimum length of 175 mm in the machine direction. The cuts should be clean and straight. At least three strips should be taken from each material sample.

Test Conditions

23°C 2°C and 50% RH 5% RH. The test sample or test strips should be conditioned for not less than 4 hours before testing.

Procedure

Remove the backing material from each strip and place the adhesive coated facing material, adhesive side down, on to a clean test plate using light finger pressure. Roll twice in each direction with the standard FINAT test roller at a speed of approximately 10mm per second to obtain intimate between the adhesive mass and the surface.

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After applying the strip to the test plate, leave for a period of 20 minutes before testing. Repeat the procedure with a second set of strips and leave for a period of 24 hours before testing. Fix the test plate and strip into the horizontal which has been secured into the bottom jaw of the tensile tester. Set the machine at 300mm per minute jaw separation rate. Carry out the test taking at least five readings at 10 mm intervals from the centre section of the test strip. Average the five or more readings for each strip. Results

Peel adhesion (90°) is expressed as the average result for the strips tested in Newtons per 25 mm width for either 20 minutes or 24 hours application time. Failure Description Code Clear - no visible stain on . PS Stain - discoloration of test area, but no tacky residue. CF Cohesive Failure - the adhesive film is split during the test, leaving residue of adhesive on both the and the front material. AT Adhesive Transfer - the adhesive separates cleanly from the front material, leaving adhesive film on the test . The approximate extent of transfer should be quoted as percentage PT Paper Tear - the adhesive force exceeds the strength of a paper facing material. The results quoted should be the maximum reached before the paper tears.

Notes

1. The test plates must be thoroughly cleaned so that no trace of adhesive, grease, silicone or moisture is left on the surface. The following solvents can be used to clean the test plates: – Diacetone alcohol non-residual, technical grade or better – Methyl Ethyl Ketone (MEK) – Acetone – Methanol 95 % – n-Heptane – Ethyl Acetate The cleaning material must be absorbent, e.g. surgical gauge, cotton wool or tissue. To be suitable, materials must be lint-free during use, absorbent, contain no additives that are soluble in the solvents listed above, and made exclusively from virgin materials. Dispense one of the solvents listed above on to the , wiping it to dryness with fresh absorbent cleaning material. Repeat for a total of three washes with the solvent. Final wipe shall be with MEK or acetone. Alternative methods which remove contamination properly can be adopted, e.g. ultrasonic cleaning. Prior to use, the cleaned plates should be left for 4 hours under standard test conditions. Care should be taken to handle clean plates by the edge only.

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2. Alternative surfaces to plate glass can be used such as stainless steel or aluminium, but this must be clearly stated alongside the results. 3. If adhesion values are required when paper tear has occurred then this test can be conducted at lower jaw separation rates quoting the latter against the results. 4. Conversion 1 kgf- = 9.81 N Issued October 1985 Revised March 1999 Revised May 2001

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FINAT Technical Handbook 6th edition, 2001

FTM 3

FINAT Test Method no. 3 Low speed release force

Scope

This test method allows the end to determine the force required to separate the release backing from the pressure sensitive adhesive coated face material. It may be used in the preliminary evaluation of the conversion aspects of the laminate, - very low values may create label fly during conversion or application high values may produce web break when skeleton stripping die cut labels or dispensing failure during automatic application.

Definition

Low speed release force is defined as the force required to separate a pressure sensitive adhesive coated material from its backing or protective sheet (or vice versa) at an angle of 180° and a jaw separation rate of 300mm per minute.

Test Equipment

A tensile tester or similar machine, capable of peeling a laminate through an angle of 180° with a jaw separation rate of 300mm per minute with an accuracy of 2%. The equipment should be fitted with a back plate to which the test strip can be attached in order to maintain an angle of peel of 180°. Metal or glass pressure plates loaded to give a pressure of 6.86 kPa 2 (70 g/cm ) on the test piece.

Test Pieces

These should be strips taken from a representative sample of material. The strips should be 50mm wide and have a minimum length of 175mm in the machine direction. The cuts should be clean and straight. At least three strips should be taken from each sample.

Test Conditions

Place the strips under test between two flat metal or glass plates and keep for 20 hours at 23°C ±2oC under a pressure of 6.86 kPs (70 g/cm2) to ensure good between the release material and the adhesive. Up to 20 strips can be kept between the plates. After storage in this manner, take the strips from between the plates and keep for not less than 4 hours at the standard test conditions of 23 2°C and 50 % RH 5 % RH.

Procedure

Fix each strip to the plate by means of a double sided tape (which should cover the full test area of the sample), so that the laminate can be peeled apart at an angle of 180°. The facing material may be peeled from the release substrate, or vice versa, depending on how the sample is applied to the plate. The method of peel must be quoted with the results. Set the machine at 300mm per minute jaw separation rate, carry out the test taking five readings at 10 mm intervals from the centre section of the test strip. Average the five readings for each strip.

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Results

Low speed release force is expressed as the average result for the strips tested in centiNewton per 50mm width.

Notes:

Conversion 1 kgf- = 981cN.

Revised March 1990 Revised March 1999 Revised May 2001

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FINAT Technical Handbook 6th edition, 2001

FTM 4

FINAT Test Method no. 4 High speed release force

Scope

This test method allows the label to assess the separation force of a laminate at speeds comparable to those typically used to convert and dispense the material. It therefore gives a far more meaningful assessment of the conversion characteristics than FTM 3. Very low values may create label fly during conversion or application. High values may produce web break when skeleton stripping die cut labels or dispensing failure during automatic application.

Definition

High speed release force is defined as the force required to separate: (mode 1) a pressure sensitive adhesive coated material from its backing or protective sheet, (mode 2) the backing from the adhesive coated material, both at an angle of 180° and at jaw separation rates between 10m and 300m per minute. The two modes will mostly give different results.

Test Equipment

A machine capable of peeling a laminate through an angle of 180° with a jaw separation rate range of 10 - 300m per minute. The machine should preferably have a facility for recording the release force continuously (see notes).

Test Pieces

These should be taken from a representative sample of material. The strips should be 25 mm wide and have a minimum length of 300mm in the machine direction. The testing device may require extra length for clamping the material. The strips must be free from damage (creases, blisters etc.) and cut with clean edges.

Test Conditions

The material under test is placed between two flat metal or glass plates and kept for 20 hours at 23°C 2°C under a pressure of 6.87 kPa (70 g/cm2) to ensure good between the release paper and the adhesive. Up to 20 strips can be kept between the plates. After storage in this manner, the strips should be taken from between the glass plates and kept for not less than 4 hours at the standard test conditions of 23°C 2°C and 50% RH 5% RH. Accelerated ageing may be carried out by placing a similar set of strips between two flat metal or glass plates and keeping for 20 hours in an air circulating oven at 70°C 5°C. The strips should then be removed and conditioned for at least 4 hours as above. See also FTM 5

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Procedure

Mode 1: Separating adhesive coated face material from release backing When the adhesive component is pulled from the backing by a roller mechanism it may be necessary to prevent the adhesive sticking to the rollers in the drive mechanism. This may be achieved by a strip of glassine release base covering the exposed adhesive. The protective strip should be 5-10 mm wider and 20-30 mm longer than the adhesive component test piece, to minimise the risk of misalignment. The procedure is as follows: 1. Place the test piece in the machine and fix the release backing in the load cell clamp. 2. Place the protective strip (silicone side) squarely on and parallel to the adhesive side of the adhesive face component, in such a way that the protective strip will follow the adhesive component during the release test. 3. Set the machine at the desired test speed. 4. Place the adhesive component with protective strip in the drive roller mechanism and carry out the test, noting either the individual display reading or the average reading from the recorder. If a sample width of 50mm is used, the adhesive coated face paper cannot be removed in the described way. Check the manual of the testing device whether release values below 15 cN/25mm are reliable. Mode 2. Separating release backing from adhesive coated face material The procedure is as described above except that the position of the laminate components are reversed and it is not necessary to use a protective strip.

Results

High speed release force is expressed as the peak or average result for the strips tested in centiNewtons (cN) per 25mm width. This should be quoted alongside the test speed used and the means of peeling employed: (mode 1 ) facing material from release backing or (mode 2) release paper from facing material. The type of result (peak or average) should be quoted.

Notes

1. Results based on merely peak and/or average release force values may be misleading, particularly at high separation speeds. It is strongly recommended that the release test device be used with a high speed trace recorder. 2. Conversion 1 kgf- = 981 cN

Issued October 1988 Revised October 1995 Revised March 1999 Revised May 2001

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FINAT Technical Handbook 6th edition, 2001

FTM 5

FINAT Test Method no. 5 Resistance to elevated temperatures

Scope

This test method is suitable for rating laminate constructions according to their ability to withstand elevated temperatures and/or extended storage periods. It may be combined with other FINAT Test Methods.

Procedure

Place the strips, still covered with their protective backing material in the test oven under the test conditions without allowing them to come into with each other (i.e. hanging freely). Retain the control set of strips at 23°C ± 2°C and 50% RH ± 5% RH . At the end of the test period, remove the strips from the oven and, after allowing the specified conditioning period appropriate to each test method, test the strips, together with the control strips, by the appropriate FINAT test method (FTM 1, 2, 8 or 9). For additional guidelines see Section 13. The single strip and a control should also be evaluated for discoloration and strike through of adhesive by removing them from their protective release material, then adhering to black card and carrying out a visual examination.

Results

Resistance to elevated temperatures is expressed as the percentage reduction (any increase being denoted as such) in each average value when compared to the control. The discoloration and strike through should be reported descriptively as nil, slight, moderate or severe. All conditions should be carefully reported.

Issued October 1985 Revised March 1999 Revised May 2001

FINAT Technical Handbook 6th edition, 2001

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FTM 6

FINAT Test Method no. 6 Resistance to ultra-violet light

Scope

This test method offers a means of comparing the weathering characteristics of self adhesive laminates.

Definition

Ultra-violet light is the high energy light which is largely responsible for the deterioration of adhesive coated materials during weathering. The resistance of a pressure sensitive material to ultra-violet light is defined as the reduction in peel adhesion (FTM 1 or 2), shear (FTM 8), loop tack (FTM 9) and the degree of adhesive discoloration and strike through after exposure to a defined amount of radiation similar in spectrum to that of solar radiation.

Test Equipment

Any apparatus capable of exposing samples to a mercury vapour lamp, xenon arc or other radiation source with similar spectral characteristics to that of solar radiation. The temperature reached by the sample should not exceed 50°C.

Test Pieces

These should be strips taken from a representative sample of material. The strips should be 25mm wide and have a minimum length of 175 mm in the machine direction. The cuts should be clean and straight. A minimum of three strips are required for each physical property being tested together with a single strip for evaluation of discoloration and strike through. A duplicate set of strips is also required to act as control.

Test Conditions

The distance of the samples from the radiation source and the time of exposure should be such that, at this distance/time combination, a standard Blue Wool Scale No. 4 will fade by Grey Scale step 3 (see Notes). This defines the total quantity of radiation falling on the sample and is approximately equivalent to 1 month summer sunlight. Since lamp characteristics change with time, the distance/time combination should be checked at intervals during the life of the lamp. The test may also be conducted under more severe conditions when appropriate by using Blue Wool Scale No. 5 or No. 6 as the starting point for the standard, each unit step in the Blue Wool Scale approximately doubling the exposure level.

Procedure

Expose the strips to the lamp for the time and distance defined under "Test Conditions". The strips should be exposed as a laminate with the facing material towards the lamp. Retain the control set of strips at 23°C ± 2°C and 50% RH ± 5% RH. At the end of the test period remove the strips from the apparatus and, after allowing the specified conditioning period appropriate to each test method, test the strips, together with the control strips, by the appropriate test method (FTM 1, 2, 8 or 9). The single strip and a control should also be evaluated for discoloration and strike through of adhesive by removing them from their protective release material, then adhering to black card and carrying out a visual examination.

Results

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Resistance to ultra-violet light is expressed as the percentage reduction (any increases being denoted as such) in each average value when compared to the control samples.

FINAT Technical Handbook 6th edition, 2001

The discoloration and strike-through should be reported descriptively as nil, slight, moderate or severe. If conditions other than the standard (Blue Wool Scale 4 - Grey Wool Scale 3) are used, then this must be stated. Notes

1. The exposure levels are taken from the International Standard ISO 105: 1978 ‘Textiles - Tests for Colour Fastness’. The equivalent British Standard is BS 1006:1978 – ‘Colour Fastness of Textiles and Leather’. 2. The Blue Wool Scales and Grey Scales are obtainable from various national Standard Organisations including: British Standards Institution 2 Park Street, London WA 2BS DIN Deutsches Institut fur Normung e.V. Beuth Verlag GmbH Burggrafenstrasse 6 D-10787 Berlin Tel. +49 30 2601-2292 Japanese Standards Association 1-24 Akasaka 4 Minatoku, Tokyo Institut Belge de Normalisation Av. de la Brabançonne 29 B-1040 Bruxelles Association Française de Normalisation Tour Europe, CEDEX 7 F-92080 Paris la Defense

Issued 1985 Revised October 1995 Revised March 1999 Revised May 2001

FINAT Technical Handbook 6th edition, 2001

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FTM 7

FINAT Test Method no. 7 Silicone Coat Weight

Scope

This test method provides a quantitative determination of the amount of silicone release coating present on the release base materials used in the manufacture of pressure sensitive laminates for self adhesive labels or other release liner applications.

Definition

Silicone coat weight is expressed as the quantity of cured silicone release coating on a standard area of release base material. It is expressed in grams per square metre (g/m2). Silicone coat weight can be one of the key parameters in assessing the quality of release base performance.

Test Equipment

This method is for the laboratory determination and also routine production measurement of silicone coat weight using the principle of X-ray fluorescence spectrometry (XRF). A number of benchtop XRF analysers are commercially available the most commonly used being the Oxford Instruments Lab-X 3000, the Metorex XMET 800 and the Spectro T200/Titan. (supplier addresses and websites ref. section test equipment p.61 sec 2.3)

Test Specimens

A suitable number of test specimens are taken from the representative area of the release base sheet of laminate or from the pre siliconised release material under investigation. With each type of XRF analyser a suitable sample cutter is generally available. Contamination of the samples especially from any silicone materials present in the area must be avoided. Sample discs should be cut or punched onto a clean sheet of tissue paper and should then be handled with tweezers. Samples require no pre conditioning.

Procedure

With most analysers samples are placed into a special device designed by the manufacturers to handle paper or film substrates. They are then automatically introduced into the analyser where they are ultimately moved into a special measurement chamber where irradiation with primary X-rays results in the emission of resultant secondary fluorescence X- rays characteristic of the element being analysed, in this case silicon. After a period of time e.g 30-60 seconds measurements are complete and the software will provide a read out of coat weight directly in g/m2. silicone, (Polydimethylsiloxane). Ref. Results below. The exact procedure for the operation of these instruments has to be followed from the operator’s manual of the appropriate instrument supplier. However some general points are worth noting.The operator inputs are accomplished via software control and are activated using an integral keypad or linked computer system. Software messages and results are shown on the analyser liquid crystal displays or on the monitor of the computer system. The XRF technique is a comparative rather than an absolute method of analysis and therefore a calibration curve must be established before routine analysis can be performed. This is explained for each instrument and the suppliers can offer sets of calibration standards, information on standardisation, calibration and blank correction. Variations in technique are needed to accommodate different types of substrate e.g. Glassine paper and Clay coated paper, and a blank sample of uncoated substrate is generally needed to correct for silicon present in the uncoated base paper or film.

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FINAT Technical Handbook 6th edition, 2001

Results

These are directly provided in grams per square metre silicone. Care should be taken when converting from elemental silicon to silicone as release coating. The majority of polymers are based upon polydimethylsiloxane but some silicones, in particular radiation cured may need a different conversion factor to allow for different chemistries. If in doubt consult the silicone supplier. Several samples should be taken from a representative coated substrate, and for wide off coater samples the position across the web should be noted since variations can occur. In general the greater the count time the greater the precision. Accuracy within the range of +/- 0.05 to 0.01 (g/m2) have been reported within the industry. Reference: L .Price and L. Morrison, Spectroscopy, Vol. 7, No 6, July/August 1992 pp 32-38

Issued April 2001

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FTM 8

FINAT Test Method no. 8 Resistance to shear from a standard surface

Scope

This test method measures the ability of an adhesive to withstand static forces applied in the same plane as the labelstock. It gives an indication of the likely mode of bond failure, i.e. adhesive failure or cohesion failure.

Definition

Resistance to shear from a standard surface is defined as the time required for a standard area of pressure sensitive coated material to slide from a standard flat surface in a direction parallel to the surface.

Test Equipment

A rack or jig to hold the test plate precisely 2° from the vertical (see diagram below). 1 kg weight. A standard FINAT Test roller. Test plates made of float glass or similar plate glass (Kristallspiegelglas, verre glace).

Test Pieces

These should be strips taken from a representative sample of material. The strips should be 25mm wide and have a minimum length of 175mm in the machine direction. The cuts should be clean and straight. At least three strips should be taken from each material sample.

Test Conditions

23°C ± 2°C and 50 % RH ± 5% RH. The test sample or test strips should be conditioned for not less than 4 hours before testing.

Procedure

Remove the backing material from each strip and place the adhesive coated facing material, adhesive side down, on to a clean test plate using light finger pressure, so that a square of pressure sensitive coated material, 25mm x 25mm, is in actual with the surface. Roll twice in each direction with the standard FINAT test roller at a speed of approximately 10 mm per second to obtain intimate between the adhesive mass and the surface. Any strips found by inspection to have air bubbles trapped between the adhesive mass and test plate should be discarded. Place the test plate into the rack of jig and attach the 1 kg weight to the free end of the test strip (not less than 5 minutes and not more than 10 minutes after rolling). Note the time taken for the strips to part from the plate.

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Results

Resistance to shear from a standard surface is expressed as the average time taken for the three strips to shear from the test plate. Failure Description Code: Clear - no visible stain on . PS Stain - discoloration of test area, but no tacky residue. CF Cohesive Failure - the adhesive film is split during the test, leaving residue of adhesive on both the and the front material. AT Adhesive Transfer - the adhesive separates cleanly from the front material, leaving adhesive film on the test . The approximate extent of transfer should be quoted as percentage

Notes

1. The test plates must be thoroughly cleaned so that no trace of adhesive, grease, silicone or moisture is left on the surface. The following solvents can be used to clean the test plates: – Diacetone alcohol non-residual, technical grade or better – Methyl Ethyl Ketone (MEK) – Acetone – Methanol 95 % – n-Heptane – Ethyl Acetate The cleaning material must be absorbent, e.g. surgical gauze, cotton wool or tissue. To be suitable, materials must be lint-free during use, absorbent, contain no additives that are soluble in the solvents listed above, and made exclusively from virgin materials. Dispense one of the solvents listed above on to the , wiping it to dryness with fresh absorbent cleaning material. Repeat for a total of three washes with the solvent. Final wipe shall be with MEK or acetone. Alternative methods which remove contamination properly can be adopted, e.g. ultrasonic cleaning. Prior to use, the cleaned plates should be left for 4 hours under standard test conditions. Care should be taken to handle clean plates by the edge only. 2. Alternative surfaces to plate glass can be used such as stainless steel or aluminium but this must be clearly stated alongside the results. 3. Alternative weights can be used, but these must be clearly stated alongside the results.

Issued October 1985 Revised March 1999 Revised May 2001

FINAT Technical Handbook 6th edition, 2001

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FTM 9

FINAT Test Method no. 9 ‘Loop’ tack measurement

Scope

This test method describes a means of assessing probably the most important and yet the hardest to measure property of pressure sensitive materials, the tack. The method described should allow the end to compare the "initial grab" or "application tack" of different laminates and can be extremely useful to those working with automatic labelling equipment where this property is of particular importance.

Definition

The ‘loop’ tack value of a pressure sensitive material is expressed as the force required to separate, at a specified speed, a loop of material (adhesive outermost) which has been brought into with a specified area of a standard surface.

Test Equipment

A tensile tester or similar machine with reversing facility and a vertical jaw separation rate of 300mm per minute with an accuracy of ± 2%. It should also have a capability of measuring direct loads up to at least 20 Newtons with an accuracy of ± 2%. A flat plate made of float glass or equivalent plate glass measuring 25 ± 0.5 mm x 30 ± 2.0 mm x minimum thickness 3.0 mm. A metal peg is attached at the centre of one face of the plate. The dimensions of the peg should be such that the peg can be clamped in the lower jaw of the tensometer.

Test Pieces

These should be strips taken from a representative sample of material. The strips should be 25 mm wide and have a minimum length of 175 mm in the machine direction. The cuts should be clean and straight. At least five strips should be taken from each sample.

Test Conditions

23°C ± 2°C and 50% RH ± 5% RH. The test sample or test strips should be conditioned for not less than 4 hours before testing.

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Procedure

Remove the backing material from each strip immediately prior to the test being carried out. Hold the two ends of the adhesive coated facing material strip and from the strip into a loop, adhesive surface outermost, by bringing the two ends together. Clamp the ends of the loop for a distance of 10 mm into the top jaw of the ensile tester leaving the loop hanging vertically downwards. The sides of the jaw should be protected from the adhesive coating. Clamp the glass plate in the lower jaw with the longer axis of the plate positioned at right angles to the long axis of the strip. Start the machine and bring the loop into with the glass plate at a speed of 300 mm per minute. When full over the glass plate has been achieved (25 mm x 25 mm) immediately reverse the direction of the machine and allow separation to take place at a speed of 300 mm per minute. It is important that delay in reversing direction is kept to an absolute minimum. Record the maximum force necessary to completely separate each loop from the glass plate.

Results

‘Loop’ tack is expressed as the average value (ignoring the initial peak) and range for the five strips tested in Newtons. If the force exceeds the strength of a paper facing material, the result quoted should be the maximum reached before the paper tears and this result should be followed by the postscript PT (paper tear). If adhesive transfer occurs, this should be indicated by the letters AT, and the approximate extend of transfer quoted as percentage.

Notes

1. The rigidity of the sample affects the results and must be considered when comparing different adhesives on different facing materials. 2. The test plates must be thoroughly cleaned so that no trace of adhesive, grease, silicone or moisture is left on the surface. The following solvents can be used to clean the test plates: – Diacetone alcohol non-residual, technical grade or better – Methyl Ethyl Ketone (MEK) – Acetone – Methanol 95 % – n-Heptane – Ethyl Acetate The cleaning material must be absorbent, e.g. surgical gauze, cotton wool or tissue. To be suitable, materials must be lint-free during use, absorbent, contain no additives that are soluble in the solvents listed above, and made exclusively from virgin materials.

Dispense one of the solvents listed above on to the , wiping it to dryness with fresh absorbent cleaning material. Repeat for a total of three washes with the solvent. Final wipe shall be with MEK or acetone.

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Alternative methods which remove contamination properly can be adopted, e.g. ultrasonic cleaning. Prior to use, the cleaned plates should be left for 4 hours under standard test conditions. Care should be taken to handle clean plates by the edge only. 3. Conversion 1 kgf- = 9.81 Newton.

Issued October 1985 Revised March 1999 Revised May 2001

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FTM 10

FlNAT Test Method no. 10 Quality of silicone coated substrates for self-adhesive laminates: release force

Scope

This test method describes a simple method of assessing the suitability of a siliconised (or indeed any other type of release) backing material for pressure sensitive lamination .

Definition

Release force is defined as the force required to separate a pressure sensitive adhesive coated material from its backing or protective sheet (or vice versa) under specified conditions and at a specified angle and speed.

Test Equipment

A tensile tester or similar machine, capable of peeling a laminate through an angle of 180° at a jaw separation rate of 300 mm per minute and with an accuracy of ± 2%. A circulating hot air oven capable of maintaining a temperature of 70 ± 2°C. A standard FINAT test roller. Metal or glass pressure plates loaded to give a pressure of 6.86 kPa (70 g/cm2) on the test pieces. A standard pressure-sensitive adhesive tape, 25 mm wide, or a standard pressure sensitive adhesive coated facing paper (see Notes).

Test Pieces

The silicone coated substrate may be tested either against the standard tape or against a standard pressure sensitive adhesive coated facing paper, the adhesive chosen being that which will simulate the end application for which the release paper is intended. Take a representative sample of the silicone coated substrate of minimum dimensions 450 mm x 250 mm. Apply to this, using light finger pressure, the adhesive tape in strips along the machine direction. Alternatively apply a suitable sized sheet of pressure sensitive adhesive coated facing paper to the sample. Cut test strips 25 mm wide and 175 mm in the machine direction. The cuts should be clean and straight. Roll the strips twice in each direction with the standard FINAT test roller at a speed of approximately 10 mm per second. At least six strips should be prepared from each sample if subsequent adhesion tests are to be carried out. In the case of samples showing very low release force, the width (and hence the width of tape) may be 50mm in order to obtain a meaningful measurement. However, release force should still be expressed as release force per 25mm width.

Test Conditions

Place the strips under test between two flat metal or glass plates and keep for 20 hours at 23°C ± 2°C under a pressure of 6.86 kPa (70 g/cm2) to ensure good between the silicone coated substrate and the adhesive.

After storage in this manner take the strips from between the plates and keep for not less than 4 hours at the standard test conditions of 23°C ± 2°C, 50 % RH ± 5% RH.

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Accelerated ageing may be carried out by placing a similar set of strips between two flat metal or glass plates and keeping it for 20 hours in an air circulating oven at 70°C ± 5°C. The strips should then be removed and conditioned for at least 4 hours as above. Procedure

Fix each strip in the machine so that the tape or facing material can be stripped away from the silicone coated substrate at an angle of peel of 180°. Set the machine to operate at 300mm per minute jaw separation rate. Carry out the test taking at least five readings at 10 mm intervals from the centre section of the test trip. Average the five or more readings for each strip.

Results

Release force is expressed as the average result for the strips tested in Newtons per 25 mm width either under standard conditions or under accelerated ageing conditions.

Notes

1. The strips should be retained for subsequent adhesion testing. 2. See FTM 11 for interpretation of results. 3. The adhesive tape or adhesive coated facing paper used should be as stable to changes in temperature as possible and of steady and reproducible adhesion value. 4. Conversion 1 kgf- = 9.81 Newton. See also notes for FTM 11.

Issued October, 1985 Revised March 1999 Revised May 2001

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FTM 11

FINAT Test Method no. 11 Quality of silicone coated substrates for self-adhesive laminates: subsequent adhesion

Scope

This test method describes a technique whereby the effect of the release surface on the adhesive properties can be assessed. It is of particular interest both to manufacturers of release paper and also to pressure sensitive laminate manufacturers in determining the key and degree of cure of the release system.

Definition

Subsequent adhesion is defined as the force required, at a specified angle and speed, to remove a pressure sensitive adhesive coated material from a standard test plate after it has previously been in with a silicone coated substrate under specified conditions. Percentage subsequent adhesion is expressed as the percentage ratio of this result compared with the adhesion of similar material which has not been in with the silicone coated substrate.

Test Equipment

A tensile tester or similar machine, capable of peeling a laminate through an angle of 180° with a jaw separation rate of 300mm per minute with an accuracy of ± 2%. Test plates made of float glass or equivalent plate glass (Kristallspiegelglas, verre glace). A standard FINAT test roller. The test samples from FTM 10. A standard pressure sensitive tape, 25mm wide, or a standard pressure sensitive adhesive coated facing paper (see Notes to FTM 10 and FTM 11).

Test Pieces

These are the 175mm x 25mm tape or pressure sensitive adhesive coated facing paper strips which were peeled from the silicone coated substrate in FTM 10, plus a control set of at least three strips from the standard tape or pressure sensitive adhesive coated facing paper which have not been in with the silicone coated substrate under test.

Test Conditions

23°C ± 2°C and 50 % RH ± 5% RH. The test strips should be conditioned for not less than 4 hours before testing.

Procedure

Apply the test strips of adhesive coated tape or facing paper from FTM 10, adhesive side down, on to a clean test plate using light finger pressure. Roll twice in each direction with the standard FINAT test roller at a speed of approximately 10 mm per second to obtain intimate between the adhesive mass and the surface. After applying the strip to the test plate leave for a period of 20 minutes before testing. Prepare a second set of strips and leave for a period of 24 hours before testing.

Fix the test plate and sample in the machine so that the angle of peel is 180°. Set the machine at 300mm per minute jaw separation rate. Carry out the test taking at least five readings at 10mm intervals from the centre section of each test strip. Average the five or more readings for each strip.

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This procedure should then be repeated for the control set of tape or adhesive coated facing paper strips which have not been in with the silicone coated substrate in order to determine percentage subsequent adhesion. Results

Subsequent adhesion is expressed as the average result for the strips tested in Newtons per 25 mm width for either 20 minutes or 24 hours application time.

Subsequent adhesion % = 100 X

Force required to remove test tape Force required to remove control tape

If the adhesive force exceeds the strength of a paper facing material the result quoted should be the maximum reached before the paper tears and this result should be followed by the postscript PT. If adhesive transfer occurs, this should be indicated by the letters AT.

Notes

1. Low values of release force (FTM 10) in conjunction with high subsequent adhesion (FTM 11) usually indicate that the silicone coating has been properly applied and cured. 2. High values of release force (FTM 10) usually indicate that the silicone coating is inadequate or uneven (unless the product is designed to give high release) or that the adhesive has reacted with an improperly cured film. 3. Low values of release force (FTM 10) with low percentage subsequent adhesion values indicate silicone migration. However, the subsequent adhesive strength of an adhesive after with silicone coated paper is very much dependent on the surface texture of the substrate to which the release coating has been applied. In general, the smoother the surface of the substrate, the higher will be the percentage subsequent adhesion value obtained. Values of 70-80% are not unusual. 4. Care should be taken in the interpretation of the results obtained from the accelerated ageing release test carried out at elevated temperature as the rheological properties of adhesives are temperature dependent. Excessive flow of adhesive at high temperature can give high release values, particularly with pinholed or imperfect silicone coatings. 5. The test plates must be thoroughly cleaned so that no trace of adhesive, grease, silicone or moisture is left on the surface. The following solvents can be used to clean the test plates: – Diacetone alcohol non-residual, technical grade or better – Methyl Ethyl Ketone (MEK) – Acetone – Methanol 95 % – n-Heptane – Ethyl Acetate

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The cleaning material must be absorbent, e.g. surgical gauze, cotton wool or tissue. To be suitable, materials must be lint-free during use, absorbent, contain no additives that are soluble in the solvents listed above, and made exclusively from virgin materials. Dispense one of the solvents listed above on to the , wiping it to dryness with fresh absorbent cleaning material. Repeat for a total of three washes with the solvent. Final wipe shall be with MEK or acetone. Alternative methods which remove contamination properly can be adopted, e.g. ultrasonic cleaning. Prior to use, the cleaned plates should be left for 4 hours under standard test conditions. Care should be taken to handle clean plates by the edge only. 6. Alternative surfaces to plate glass can be used such as stainless steel or aluminium but this must be clearly stated alongside the results. 7. If adhesion values are required when paper tear has occurred, then this test can be conducted at lower jaw separation rates quoting the latter against the results. 8. Conversion 1 kgf- = 9.81 Newton. Issued October 1985 Revised March 1999 Revised May 2001

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FTM 12

FINAT Test Method no. 12 Adhesive coat weight

Scope

This test may be used to determine with reasonable accuracy the amount of dry adhesive material applied to the surface of a pressure sensitive label construction.

Definition

Adhesive coat weight is expressed as the weight of dry adhesive on a standard area of material - in grammes per square metre (g/m2).

Test Equipment

1. A press or template enabling samples to be cut 100 cm2 in area to a high degree of accuracy. 2. A circulated hot air oven capable of maintaining a temperature of 105°C ± 2°C. 3. A balance capable of recording sample weights to an accuracy of at least ± 0.001 g. 4. A beaker of solvent - suitably chosen to enable the adhesive film to be softened prior to removal. Recommendations: a) for an acrylic adhesive - aliphatic solvent (e.g. SBP 2) + trace of aromatic solvent (e.g. toluene); b) for a rubber/resin adhesive - aliphatic solvent.

Test Specimens

Samples of 100 cm2 cut from representative positions in the web.

Test Procedure

1. The specimen is placed in an oven at 105° for five minutes. 2. It is removed and any release liner is detached. 3. Exactly one minute after removal from the oven, the weight of the specimen is recorded to at least 3 decimal places. 4. Soak the specimen in the beaker of solvent to soften the adhesive approximately one minute. 5. Remove from the beaker and carefully scrape the adhesive off completely, rinsing in clean solvent to remove any residue. 6. When all adhesive has been removed, return specimen to oven for further five minutes. 7. Exactly one minute after removal from the oven reweigh and record new weight of specimen.

Results

Subtract the final weight from the initial weight and multiply this figure by 100 to express the final result in g/m2. Carry out the test taking five specimens per sample and record the average coat weight obtained.

Note

Particular care should be taken when testing laminates manufactured from speciality papers or synthetic films (particularly vinyls) since the solvent used to remove the adhesive may also dissolve components of the face material resulting in significant errors.

Issued October, 1985 Revised March 1999 Revised May 2001

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FTM 13

FINAT Test Method no. 13 Low temperature adhesion

Scope

This test method allows a subjective assessment to be made of the ability of a pressure sensitive material to adhere under low temperature conditions.

Definition

Low temperature adhesion is defined as the ability of a pressure sensitive coated material to adhere at temperatures below 5°C. This test method allows a subjective assessment to be made of the ability of a pressure sensitive material to adhere under chill (4°C) and deep freeze (-25°C) conditions. Other test conditions are possible (see note 1) and if used should be reported with the results.

Test Equipment

A cabinet capable of maintaining a temperature of 4°C ± 1°C. A chest freezer capable of maintaining a temperature of -25°C ± 1°C. Both should be large enough to allow examination of the test specimens without removal. A standard FINAT test roller.

Test Pieces

These should be cut from a representative sample of material. The test piece should be 25 mm x 15 mm cut with the machine direction parallel to the short edge.

Test Surfaces

Polyester Glass Stainless steel Aluminium foil Low Density Polyethylene (PE - LD) High Density Polyethylene (PE - HD) Oriented Polypropylene (OPP) Where laminates or adhesives are being designed for specific applications the test surfaces should be chosen to represent the final end use. Other test surfaces may be used and should be reported with the results (see note 2).

Procedure

Place the test surfaces in the cabinet set at 4°C and the chest freezer set at -25°C twenty four hours before the start of the test. The surfaces should be dry before they are placed into the test cabinets and any filmic materials should be placed in with glass plates to ensure an even temperature distribution. The test surfaces should remain in the test cabinets at all times during the test. Holding the test pieces by the edge, remove the backing material. Place the test piece, adhesive side down, on the test surface - do not press down as this can lead to local heating - then roll once in each direction with the standard FINAT testroller, that has been conditioned for at least 4 hours to the test conditions, at a speed of approximately 10 mm/sec to obtain intimate between the adhesive mass and the surface. At least three test pieces from each laminate under test should be applied to each test surface.

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The labelled test surfaces should then be stored in the test cabinets for the prescribed period. The recommended periods are 1 hour and seven days though other time periods are possible (see note 3). The time period used should be reported with the results. After the test period, remove the test pieces from the test surfaces with the test surfaces remaining in the test cabinet and assess the adhesion. Removal of the test piece should start at one corner. If the label starts to tear removal should be attempted from the opposite corner and continued even if the label tears again. Rate the adhesion in the following manner: Rating Description 0 Label detached from the test surface. 1 Poor bond-no label tear. 2 Moderate bond - no label tear. 3 Good bond - no label tear. 4 Very good bond - up to 50% of label surface left on test plate after removal.

Results

Notes

5 Excellent bond greater than 50% of label surface left on test plate after removal . For each surface average the score of the test pieces. To obtain the overall score of the laminate average the score per surface by the number of surfaces. For adhesives designed for specific surfaces the results on those surfaces should be quoted as well as the average (see notes 4 and 5). 1. The test conditions listed in the method are only two of many possibilities. Other conditions that can be used are: * apply the labels at -40°C, test at -40°C; * apply the labels at ambient, test at 4°C, -25°C, -40°C; apply the labels at ambient to moist test surfaces, test at 4°C, -25°C, -40°C; apply the labels at 25°C,-40°C to icy surfaces, test at -25°C, -40°C. In all cases the test conditions chosen should reflect as closely as possible the final end use of the material. The chosen test conditions should be recorded with the results. 2. The test surfaces listed in the method are recommended surfaces only. Each is subject to the variations normal for commercial suppliers and the test surfaces used should be representative of that supplier’s product. 3. The test periods indicated in the method are recommended periods only. Other time periods such as 24 hours or 1 month can be used if required. In all cases the chosen time period should reflect the final application and be recorded with the results.

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4. The label substrate has considerable effect on the adhesion performance as described by this test method. As such this method should be regarded as measuring the low temperature adhesion of the label construction rather than the adhesive in isolation. 5. The maximum rating possible for a removable construction is 3. 6. Label constructions using plastic films such as PVC which may embrittle at low temperatures can give high readings on this test but be unsuitable for the final end use.

Issued October 1985 Revised March 1999 Revised May 2001

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FTM 14

FINAT Test Method no. 14 Dimensional stability

Scope

This test method allows the to assess the dimensional stability of a pressure sensitive material when subjected to specified test conditions. It is particularly relevant to synthetic film based materials such as Polyvinyl chloride (PVC), Polyethylene, Polypropylene, Polyester etc.

Definition

This property is defined as the dimensional change of a pressure sensitive material which has been applied to a standard test plate under specified conditions, when subjected to elevated temperatures.

Test Equipment

An air circulating oven maintained at 70°C ± 2°C. Test plates made of smooth aluminium or aluminium alloy 150 mm x 150 mm x 2 mm gauge. A rubber covered roller of sufficient width and a mass of 1 kg per 25 mm width. A metal ruler or a scaled magnifying glass.

Test Condition

The material to be tested should be conditioned at 23°C ± 2°C and 50% RH ± 5% RH for not less than 4 hours before application.

Test Pieces

These should be cut from a representative sample of material min. 165 mm x 165 mm square with one edge running parallel to the length-wise edge of the test material.

Procedure

Remove the backing material from each strip and place the adhesive coated facing material, adhesive side down, onto a clean test plate using light finger pressure and without stretching the material. Roll twice in each direction with the rubber covered roller at a speed of approximately 10 mm per second to obtain intimate between the adhesive and the aluminium plate surface. Then condition the applied material for 72 hours at 23°C ± 2°C and 50% RH ± 5% RH. After this conditioning procedure the applied material should be trimmed to the dimension of the test plate. The length in each direction of the applied film is measured at the centre point of the opposite sides. Insert the test plate into the oven at 70°C ± 2°C for 48 hours, after which it is removed and conditioned at 23°C ± 2°C for 10 - 15 minutes to cool. The length in each direction is re-measured at the centre points.

Results

The dimensional stability (shrinkage) is expressed as the change in dimensions expressed in mm against the original lengths; minus (-) should denote a reduction in dimension and plus (+) an increase.

Notes

1. The test conditions given can be varied to suit any particular application, whereby the conditioning time and/or the exposure time and/or the substrate (e.g. glass) and/or the temperature of the oven can be changed. This should be clearly stated alongside the test results.

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2. The quality finish and thickness of the aluminium used should be recorded. 3. Dimensional stability quoted as a percentage can be misleading and should be avoided e.g. 0.2% on 150 mm dimension cannot be related to a one metre dimension.

Issued April 1991 Revised March 1999 Revised May 2001

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FTM 15

FINAT Test Method no. 15 Surface tension of plastic films

Scope

This method covers measurement of the surface tension of plastic film surfaces in with drops of specific test fluids. Surface tension (wettability) of plastic films is one of the properties used to judge surface characteristics related to printability and adhesion of other coatings/adhesives. Although the print key or adhesion property is not dependent on the surface tension only, this method is often used as a quick practical method. It is furthermore important to note that the determined wettability characterises the immediate surface condition only, and that this condition can change during storage.

Definition

The surface tension is measured by applying to the surface of the plastic film a test fluid of known surface tension and recording the time taken for the continuous film of the fluid to break into droplets. The surface tension is defined as that level when a continuous film of the test fluid remains intact for 2 seconds.

Test Equipment

A range of test fluids. A stopwatch.

Test Pieces

The test specimens must be at least 200 mm x 10 mm taken with their length in the cross direction of the roll.

Test Condition

23°C ± 2°C and 50% RH ± 5% RH. The test sample should preferably be conditioned for not less than four hours before testing, unless an immediate reading is required.

Test Fluids

For polyethylene, polypropylene, polyester and/or similar type of films, test fluids A according to Table 1 are prepared by mixing Formamide (surface tension = 58 mN/m and 2 ethoxyethanol (surface tension 30 mN/m). Approximately 1 gramme of a blue dye (e.g. Victoria blue or Methylene blue) is added to each litre of test fluid. For plastic films such as polyvinylchloride (PVC) which are affected (e.g. swelling) by the test fluids of series A, the test fluids B shown in Table 2 are prepared by mixing methanol (surface tension 23 mN/m) and distilled water, or water of similar quality (surface tension 73 mN/m). Approximately 1 gramme of a red soluble dye (e.g. Fuchsine) is added to each litre of test fluid.

Procedure

Lay the specimen on a smooth flat surface. Spread the test fluid of known surface tension using a felt tip pen or soft brush lightly over an area of approximately 200 mm x 10 mm of the test specimen. Note the time taken for the continuous film of the fluid to break into droplets. Breaking of the fluid into drops in less than two seconds, a lower numbered test fluid should be tried. Shrinkage of the liquid film on the sides of the applied fluid does not necessarily indicate a lack of wetting. The aim is to establish the lowest reading at an optimal dwell time of two seconds. Extreme care must be taken to ensure that the film surface is not touched or contaminated in the areas in which the tests are to be made as this will influence the test results.

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Results

The lowest reading (surface tension) at an optimum dwell of two seconds is deemed equivalent to the surface tension of the test piece, and is recorded in mN/m (see Notes).

Notes

1. Ready made test fluids of series A (see Table 1 ) can be obtained from: Sherman Treaters Ltd. Dormer Road, Thame Industrial Estate Oxfordshire OX9 3UW, England Tel. +44 – 1844 – 213 686 Fax +44 – 1844 – 217 172 (Distributors in other countries also) Arcotec GmbH Rotweg 25 Postfach 1138 D-71297 Mönsheim Tel. +49 – 7044 – 92120 2. The test fluids must be kept in brown glass containers. The test fluids should be renewed depending on frequency of use, e.g. when used on a daily basis dispose of remaining fluid after three months. 3. All precautions must be maintained when handling the chemicals used in the test fluids as they can be injurious to health and can cause skin irritation. 4. The Sl unit for this property is mN/m and replaces the formerly used Dyne/cm, conversion factor being one to one. 5. Preparation of solution by volume is best done by measuring separately and adding together. 6. For more accurate determination of surface tension, angle measuring equipment is used. Such units can be purchased from Lorentzen & Wettre as a L & W Surface Wettability Tester, Code 28. However, it must be noted that the results obtained may not necessarily be comparable. 7. DIN 53 364 and ASTM D2578-67 are standards relating to surface tension measurement. 8. FINAT FTM 15 is an effective tool for quick and reliable printability assessment of print substrates in of their surface tension. Experience has shown that print substrates tend to show poor printability if their surface tension is below 38 mN/m. In this case, test prints should be produced. With surface tension levels below 31 mN/m, print substrates are no longer printable with standard printing inks at all, but will generally require special inks. The surface tension limit value (38 mN/m) is correspondingly valid for other upgrading processes, such as varnishing, gluing, laminating and hot film embossing.

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Table 1. Test Fluid Series A Surface tensions of Test Fluids Series A [mN/m]

2-Ethoxyethanol vol. %

Formamide Vol. %

30 32 34 36 38 40 42 44 46 48 50 52 54 56

100.0 89.5 73.5 57.5 46.0 36.5 28.6 22.0 17.0 13.0 9.3 6.3 3.5 1.0

10.5 26.5 42.5 54.0 63.5 71.5 78.0 83.0 87.0 90.7 93.7 96.5 99.0

Surface tensions of Test Fluids Series B [mN/m]

Methanol vol. %

Water Vol. %

30 32 34 36 38 40 42 44 46 48 50 52 54 56 58

67.0 59.8 53.5 47.9 42.8 38.3 34.2 30.5 27.1 24.0 21.1 18.5 16.0 13.7 11.6

33.0 40.2 46.5 51.1 57.2 61.7 65.8 69.5 72.9 76.0 78.9 81.5 84.0 86.3 88.4

Table 2. Test Fluid Series B

Issued April 1991 Revised March 1999 Revised May 2001

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FTM 16

FlNAT Test Method no. 16 Chemical resistance - Spot method

Definition

Chemical resistance here is defined as the ability of the pressure sensitive coated material to resist colour change when subjected to a chemical substance placed on its surface for 24 hours or 7 days at 23°C ± 2°C.

Test Equipment

Test plates. A standard FINAT test roller. Test chemical.

Procedure

Remove the backing material from the test piece and place the adhesive coated facing material, adhesive side down, onto a clean test plate. Roll twice in each direction with the standard FINAT test roller. Place the test specimen horizontally. Cover up to 50% of the exposed surface area with the test substance ensuring that it does not reach the edge of the sample, thus avoiding edge attack. Leave undisturbed for 7 days at 23°C ± 2°C. It may be necessary to cover the test container to prevent excess evaporation if a volatile chemical substance is used. At the end of the test period, wash the test specimen in a detergent solution to remove all residual chemical substance and dry carefully employing an absorbent paper or cloth. If the surface remains ‘wet’, indicating that the chemical substance still remains, an inert solvent such as industrial alcohol or white spirits should be used to remove the test chemical. Dry again carefully using absorbent paper or cloth. Immediately assess any colour change of the material or permanence of legend if a printed substrate has been employed, either as a general colour change or for individual printing ink colours.

Results

Colour change is assessed against the untreated control either descriptively as nil, slight, moderate or severe attack, rate 0 to 5 (5 excellent resistance, 0 non resistant) or by determining colour fastness against the Blue Wool Scale 4 or Grey Wool Scale 3 standards. Printing ink permanency can be assessed by measuring the key of the printing ink before and after the chemical test employing standard tesa tapes.

Notes

1. The time of surface can be varied to suit any given end application. Temperature can also be changed by placing the test piece in an oven set at the required condition. 2. This test method only allows an assessment of the chemical resistance of the surfacing material. For total product resistance, the immersion technique (FTM 17) is employed followed by bond assessment.

Issued October 1995 Revised March 1999 Revised May 2001

3. It is essential that detergents or inert solvents used for cleaning purposes are such that they have no influence on the perceived colour(s) after the completion of chemical .

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FTM 17

FINAT Test Method no. 17 Chemical resistance- Immersion method

Definition

Chemical resistance here is defined as the ability of the pressure sensitive coated material to maintain its physical and adhesive characteristics after being completely immersed in a chemical substance for 24 hours at 23°C ± 2°C.

Test Equipment

Test plates made of float glass or similar plate glass (see Note). A standard FINAT test roller. Test chemical/large beaker. Metal rule.

Test Pieces

For subsequent testing against FTM1, or assessing colour change, strips should be taken from a representative sample of material, which should be 25 mm wide and have a minimum length of 175 mm in the machine direction. The cuts should be clean and straight. At least two sets of above strips should be taken from each material sample. For measurement of dimensional change after chemical immersion, a test piece of 10 cm x 10 cm is ideally required cut with one edge running parallel to the lengthwise edge of the product.

Test Conditions

23°C ± 2°C and 50 % RH ± 5% RH. The test substance or test strips should be conditioned for not less than four hours before testing.

Procedure

Remove the backing paper from each strip/sample and place the adhesive coated material, adhesive side down, onto a clean test plate using light finger pressure. Roll twice in each direction with the standard FINAT test roller at a speed of approximately 10 mm per second, to obtain intimate between the adhesive and the test surface. Condition for 24 hours at 23°C ± 2°C. Carry out peel adhesion (180°) at 300 mm per minute (as described in FTM1) on a set of three strips. Completely immerse the second set of test samples in the chemical substance for 24 hours at 23°C ± 2°C (see note 1). It may be necessary to cover the test container to prevent excess evaporation if a volatile chemical substance is used. At the end of the test period, wash the test specimen in a detergent solution to remove all residual chemical substance and dry carefully employing an absorbent paper or cloth. If the surface remains ‘wet’, indicating that the chemical substance still remains, an inert solvent such as industrial alcohol or white spirits should be used to remove the chemical substance. Dry again carefully using absorbent paper or cloth. Condition for 1 hour at 23°C ± 2°C then measure peel adhesion (180°) as before.

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Recovery of bond can be additionally assessed by repeating the above but allowing the test samples to condition for 24 hours at 23°C ± 2°C before re-measuring peel adhesion (FTM 1). Any colour change on the test samples should also be noted. For assessment of dimensional change, immerse the ‘100 mm x 100 mm’ test sample in the chemical substance for 24 hours at 23°C ± 2°C. Dry as before and remeasure in both directions. In all of the above tests, assess any colour change of the material or permanence of legend if a printed substrate has been employed, either as a general colour change or for individual printing ink colours. Any other deterioration of the test piece, e.g. blisters, should also be noted. Results

1. Peel Adhesion An average is taken of the three strips prior to and after immersion. Determine the percentage loss in peel adhesion (180°) against the non-immersed sample. Chemical resistance (bond) can be expressed as follows: Loss o 5% 50% 75% 100%

Resistance Excellent Good Moderate Poor Non-resistant

2. Colour Fastness Colour change is assessed against the untreated control either descriptively as nil, slight, moderate or severe, rated 0 to 5 as above (5 excellent, 0 non resistant) or by determining colour fastness against the Blue Wool Scale 4 or Grey Wool Scale 3 standard. 3. Dimensional Stability This is expressed as the increase or reduction in millimetres (denoted + or -) after immersion of each sample against its original length. Notes

1. The temperature and time of immersion can be varied and alternative test substrates other than float plate glass may be used to suit any given application. 2. This test method allows an assessment of the chemical resistance of the total laminate. For an assessment of the face material only, the Spot Method (FTM 16) should be employed. 3. It is essential that detergents or inert solvents used for cleaning purposes are such that they have no influence on the perceived colour(s) after the completion of chemical .

Issued October 1995 Revised March 1999 Revised May 2001

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FTM 18

FINAT Test Method no. 18 Dynamic Shear

Scope

This method is designed to determine the resistance of an adhesive coated label stock on a standardised surface, to shear at a constant speed.

Definition

Dynamic shear is defined as the maximum force per unit width required to remove the adhesive coated label stock from a specified area in the direction parallel to the surface.

Principle

A test piece is partly adhered to a test under controlled pressure. A constant speed of deformation is applied to the free end of the test piece in the length direction of the test piece. The adhesive layer resists this deformation. This resisting force grows during the increased deformation of the adhesive, until the adhesive cannot follow the deformation any more and starts to fail. The maximum force during the test is measured.

Test equipment

An electronic tensile tester with capability of jaw separation with an accuracy of 1% or better. The movable grip should be capable of being driven at a rate of 5.0 mm/min. An accurate cutting device to cut test pieces conforming to the required dimensions. Flat stainless steel s of at least 50 mm x 50 mm, with two scribed lines over the total width of the : one at 12.7 mm and one at 25 mm as indicated in figure 1. Rubber covered steel roller as described in FINAT Test Method no. 1; Automatic rolling device is strongly recommended. Aluminium foil or polyester coated with a permanent (pressure sensitive) adhesive to eliminate elongation effects in the front material of the sample. The overlaminating film to withstand 100 Newton.

Test conditions

23°C ± 2°C and 50 % RH ± 5 % RH. The samples shall be conditioned for at least 4 hours before testing.

Sample Preparation

Laminate the aluminium foil or the polyester on the front of the sample. Then cut five test pieces of 12.7 ± 0.1 mm width and at least 50 mm length in the machine direction.

Procedure

Prior to testing, clean five test s thoroughly with nheptane. Slowly remove the backing from a test piece. Gently place the test piece in the middle of the , without applying pressure. The small edge of the test piece shall be placed against the scribed line, at 12.7 mm from the edge of the as shown in the next picture:

42

25 mm

12.7 mm

test piece

test

50 mm ore more

50 mm

FINAT Technical Handbook 6th edition, 2001

Cover the adhesive of the free part of the test piece with a strip of material. Do not use siliconised material, to prevent slip in the grips. the free part of the test piece with an extra and roll down the test piece with the roller, twice in each direction with a speed of 10 mm/s, without applying any additional pressure. An automatic rolling device is strongly recommended. Set the tensile tester to the following conditions: • initial distance between the grips: 40 mm • grip separation speed: 5 mm/min After a dwell time of 20 ± 2 minutes, the test shall be placed in the fixed grip of the tensile tester. The bottom of the grip shall be in line with the scribed line at 25 mm. In case of the fixed grip is connected to the load cell: set the force reading of the tensile tester to zero, to adjust for the weight of the . Move the lower grip to its starting position and tighten the free end of the test piece firmly to prevent slipping. Start the tensile tester and wait until and construction are completely separated. Record the maximum force during this test and the mode of failure for each test piece individually. The codes for the failures modes are listed below. Failure description code Clear - no visible stain on . PS Stain - discoloration of test area, but no tacky residue. CF Cohesive Failure - the adhesive film is split during the test, leaving residue of adhesive on both the and the front material. AT Adhesive Transfer - the adhesive separates cleanly from the front material, leaving adhesive film on the test . The approximate extent of transfer should be quoted as percentage Results

Calculate and report the mean value as well as the standard deviation of the maximum forces in Newtons per 12.7 mm width (N/12.7 mm). Also report the failure code in case the same failure mode occurred for all five measurements. In case different failure modes occurred, calculate and report the mean, standard deviation and number of measurements for each code individually (results with failure codes and PS can be combined).

Repeatability

The variance coefficient for five measurements is about 3-6%.

Remarks

The relationship between shear force and test area is curvilinear. The standard deviation increases with the width of test piece.

Notes

1. The test plates must be thoroughly cleaned so that no trace of adhesive, grease, silicone or moisture is left on the surface. The following solvents can be used to clean the test plates: – Diacetone alcohol non-residual, technical grade or better – Methyl Ethyl Ketone (MEK) – Acetone – Methanol 95 % – n-Heptane – Ethyl Acetate

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The cleaning material must be absorbent, e.g. surgical gauze, cotton wool or tissue. To be suitable, materials must be lint-free during use, absorbent, contain no additives that are soluble in the solvents listed above, and made exclusively from virgin materials. Dispense one of the solvents listed above on to the , wiping it to dryness with fresh absorbent cleaning material. Repeat for a total of three washes with the solvent. Final wipe shall be with MEK or acetone. Alternative methods which remove contamination properly can be adopted, e.g. ultrasonic cleaning. Prior to use, the cleaned plates should be left for 4 hours under standard test conditions. Care should be taken to handle clean plates by the edge only. 2. Static (FTM8) and dynamic shear do not correlate. 3. Changes in speed and substrate need to be reported. 4. s of float glass can also be used.

Issued October 1995 Revised March 1999 Revised May 2001

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FTM 19

FINAT Test Method no. 19 Recycling compatibility of self-adhesive labels

Introduction

The method is based on information from various sources which all have been dealing with this topic. This test should be the basis for further developments in adhesive technologies in future as well as for testing existing technologies. It does not simulate all recycling conditions used in the Paper and Board Industry. As certain paper mills are using waste paper as a raw material up to 80 or even 100%, 'stickies' became a serious problem in the papermaking process. The self adhesive industry has been challenged to help finding solutions. This test method is a first step in that direction. Further steps will have to be taken in close cooperation with the paper making industry in order to find solutions acceptable for both parties.

Scope

This test method allows the to determine how self-adhesive paper labels will behave in the recycling of waste paper. Waste paper contains many types of paper labels and these can produce stickies that reduce the quality of waste paper products, or lead to problems in processing.

Definition

Recycling compatible labels are labels whose adhesive does not interfere with the processing of waste paper. The adhesive must form no stickies and must not add to the burden in the water circuit of the paper mill (as measured by Chemical Oxygen Demand).

Test Equipment

Standard disintegrator ISO 5263 2 ltr/1330 ml water ± 70 g. paper Zellcheming ZM V/4/61 Slot fractionator 0.15 mm, e.g. Haindl Type 9310 Fractionator Zellcheming V/1.4/86 Industriestr. 3a, D-86438 Kissing or L&W Sommerville Fractionator AB Lorentzen & Wettre P.O.box 49006 S-10028 Stockholm Sweden Pump, reservoir Flotation cell DIN 54606/11, Voith 18 litres or PTS flotation cell, 2 litre Laboratory facility for Chem. Oxygen Demand ISO 6060 Suction filter Paper mould ISO 5269/2 DIN 54358/1 e.g. Rapid-Kothen Heatable press (e.g. photo print dryer)

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Test Material

Label paper coated with adhesive Uncoated paper consists of uncoated wood-free paper with a weight of 80 g/m2 neutral sized preferred. Fully de-ionised water, de-inking chemicals (soap, H202, alkali silicate, NaOH), H2SO4 Test ConditionsThe testing procedure consists of several test methods that are carried out one after the other. These are: test 1 Disintegration ISO 5263 >> Sheet forming ISO 5269/2 I test 2 Fractionation >> Sheet forming ISO 5269/2 I Flotation DIN 54606/1 I Sheet forming ISO 5269/2 I Chem. Oxygen Demand (COD) ISO 6060; DIN 38409-41 The adhesive coated label paper is applied to uncoated paper. The papers, thus bonded together, are cut into pieces of about 1 x 1 cm. Uncoated paper is cut into pieces 1 x 1 cm. If an 18-l Voith flotation cell is used in conjunction with a pulp concentration of 0.6%, a quantity of exactly 108 g. of paper moulding, 140 g. of pulp is required for a complete test series. If smaller flotation cells, such as the PTS, are used, smaller quantities are adequate.

Procedure

Disintegration Pulp concentration: 5% Adhesive concentration: 1 % calculated on pulp. Place 3.5 g. label paper with adhesive; 66.5 g. uncoated paper and 330 g. deionised water at 45°C in a pre-warmed disintegrator vessel and wash the whole with 1000 g water at 45°C. Adjust to pH 10-11 with a caustic soda solution of 20%. Disintegrate for 10 min at 3000 rpm. Transfer the entire contents to a 2 liters glass beaker, add 200 ml of water, to give a total quantity of 1600 ml water and 70 g. paper fibres. Prepare two lots to obtain 140 g. of fibres. Fractionation (screening) Fractionators, e.g. Haindl or Sommerville fractionators, are devices that were originally designed for fractionating groundwood. In this test, they are used to simulate screening processes in the recycling of waste paper. To meet the requirements of this simulation, it is necessary to deviate slightly from the manufacturer's operating instructions.

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Apart from the fractionator, a drum is required as a reservoir. The drum is filled with the quantity of water required to supply the fractionator. When the manufacturer's instructions are followed, this requires more than 200 l of water. To keep the degree of dilution as small as possible, only 20 l are used and are recycled. A 60 m-filter is installed between the drum and the fractionator to retain the fractionated fibres. The quantities given below take into subsequent flotation in an 18-l Voith cell. Dilute the entire suspension (3200 ml with 140 g of fibres) to 4200 ml with deionised water and divide it in 12 parts of 300 ml (10 g. of fibres each), which will be diluted further to 2000 ml with de-ionised water. Discard the rest. Fit the fractionator with a 0.15 mm slot plate. Pour 20 l of water into the drum and install a 60 m filter. Pour an above described 2000 ml suspension part into the fractionator and fractionate according to the instructions. Then remove the 60 m filter, transfer the fibres to a glass beaker, filter off and dry at 120°C without the filter paper (corresponds to the thickening step). Reuse the water from above filtration step to fractionate the next sample. Repeat this procedure 12 times to provide 120 g of fibres for paper moulding and flotation. Reuse the same water to keep the volume that has to be filtered as small as possible, to avoid losing any stickies that it contains. Filter off the circuit water and add the filter residue to the fibres. Flotation Take a quantity of fibres that corresponds to a dry weight of 108 g., dilute to 1600 ml with water and mix for 10 min at 3000 rpm in a disintegrator. Disintegrate the paper moulded samples, add the de-inking chemicals in the following order and proportions, calculated on the fibres: 0.5% soap (e.g. Servax) (100%) 3.0% alkali silicate (100%) 1.0% H202 (30%) Adjust to pH 10-11 with a caustic soda solution at 20%. Reaction time: stir slowly for 60 min at 45°C. Then repeat again the disintegration step for 3 min to disintegrate the paper moulded samples in the disintegrator. Fill 5 l of water into the Voith cell, add the above sample and then fill to the brim with water. This gives 18 l of suspension with 108 g. of fibres, i.e. a pulp density of 0.6%. Treat for 10 min with an air throughput of 240 l/h. The level must be maintained constant throughout the test and water added accordingly. Push foam towards the automatic scraper manually using a hand-held scraper. Catch the overflow, filter and dry it and calculate the loss. Remove the reclaimed pulp and immediately adjust to pH 6.5-7 with H2SO4 to prevent alkali yellowing. Sheet forming The paper is moulded in a Rapid-Kothen paper mould according to PTS PR 252/90 (DIN 54 358 Part 1 or ISO 5269/2). Take a quantity of suspension to give a sheet with an oven-dry weight of about 2 g. (equivalent to 62 g/m2). Place the sample in the sheet mould dilute to 3 l with water, then apply vacuum to the wire.

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Transfer the sheet that has formed on the wire to a filter paper, smooth it and first allow it to dry in the air. Then place this sample paper sheet between two sheets of filter paper and dry at 90°C for 5 min in a heated press. Results

Specify test equipment, e.g. Fractionator, Flotation cell. Sheets moulded according to PTS PR 252/90 are evaluated. Determine: • whether the sample sheet sticks to the upper or lower filter paper; • whether the sample sheet is damaged when it is peeled from the filter papers; • whether it contains stickies, visible as transparent spots when held against the light. Record size and frequency of the spots. If the sample sheets contain neither transparent spots, nor any spots of contamination that are visible to the naked eye, nor any adhesive impurities, the label paper is regarded as repulpable or recycling compatible.

Notes

Recycling compatible labels (or self adhesive laminate) should provide positive results at sheet forming described above and COD analysis carried out at the flotation step. Hydrodispersable self adhesive laminates already exhibit no contamination in the sheets obtained after the disintegration step. PTS references above concern recommendations of Papier Technische Stiftung and the ISO and DIN standards to which they relate are given where appropriate.

Issued December 1995 Revised March 1999 Revised May 2001

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FINAT Technical Handbook 6th edition, 2001

66,5 gr uncoated Label paper (80 gr/m2) 3,5 gr adhesive coated label paper (80 gr/m2 paper + 20 gr/m2 adhesive) no release liner used Paper samples cut in 1 x 1 cm No swelling

Quantity of pulp relates to Voith Flotation Cell, size 18 ltr. Quantity to be changed with other cell volumes

Test 1 Disintegration 5 % Pulp 1 % Adhesive 45° C deionised water/pH 10-11 (NaOH)

Test 2 Screening Fractionator e.g. Haindl or Sommerville Slot Screen 0,15 mm Flotation Addition of Deinking Chemicals 0,1 % Soap 3,0 % Waterglass, Sodium Silikate aprox. 2 % NaOH to pH 10-11 1 % H2O2

Standard Desintegrator 2 ltr/1330 ml Water + 70 g Paper Zellcheming ZM V/4/61 - ISO 5263 10 min x 3000 Rpm = 30 000 R

Sheet Forming 3 - 5 sheets pH = 7 Sheet Test PTS 252/90 ISO 5269/2 Drying minimum 90° C, 5 min heated press

Filtrate: COD ISO 6060

Reaction time 90 min 40 - 45° C Homogenisation, slow stirring Flotation 0,6 Pulp Konz. in deionised water pH = 10,5 Temp.: 45° C

Sheet Forming pH = 7 Sheet Test PTS 252/90 ISO 5269/2 Drying 90° C, 5 min heated press

Filtrate: COD ISO 606 1986 Laser Detector to be introduced

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FTM 20

FINAT- Test Method no. 20 Fluorescence and whiteness

Introduction

Fluorescent substances in papers, inks and coatings are used in labels for spotting and identifying particular types of labels. Fluorescent brighteners impart increased brightness or whiteness to label papers. Assessment of whiteness requires a specified standard light spectrum including a defined range and intensity of ultraviolet radiation. Fluorescence is the emission of light in the visible or adjacent UV or IR spectrum, from matter that is suitably energised by incident radiation. The whiteness of paper or textiles may be enhanced by the fluorescence of 'optical brighteners' that convert the invisible UV component of daylight into visible light. The material thus appears brighter and whiter. The whiteness of an optically brightened paper depends on: 1. chemical structure of the optical brightener; 2. concentration of brightener; 3. the 'activation potential' of paper fibres in relation to the brightener; 4. the UV component of incident light (this means that for correct measurement of whiteness a well defined standard light source is required).

Test methods

For inspection and control purposes test methods outlined here concern (A) fluorescence and (B) whiteness. A Fluorescence 1. A surface printed with fluorescent inks or optical brighteners is viewed under UV light which reveals whether the print is as intended. 2. Actual measurement of fluorescence is possible with equipment (as supplied by SICK or LAETUS) that emits ultraviolet light of controlled intensity and measures reflected light at longer wavelengths. A pre-set threshold allows the equipment to decide whether the printing is satisfactory or whether a label is present or not. B Whiteness Whiteness is the result of basic white colour of the material and the effect of optical brightener added. The effect of optical brighteners can only be appreciated under a light source containing ultraviolet similar to daylight. 1. A set of twelve whiteness calibration plates was available from CIBA-GEIGY. Steps 1 to 4 do not contain any optical brightener but have decreasing doses of yellow pigment. Steps 5 to 12 have increasing doses of optical brightener. CIBA GEIGY no longer produces this set, but it is still used as common standard. Based on the same concept, LAETUS has developed a ruler with a twelve step whiteness scale allowing visual assessment of the whiteness of a paper surface. Again, the light used for such an assessment should combine UV-light, otherwise no fluorescence will occur. Comparative testing is also possible using the analogue output (in milliamps) of a fluorescence testing device.

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2. The best assessment of whiteness is obtained using a spectrophotometer that allows UV calibration of its light source (normally standard source D65). One such device is the Datacolor Elrepho 3000. White is in fact a colour like red, green or blue and may be determined with colorimetric methods. The difference is that white has high brightness and low saturation, which makes measurement more difficult than for a high saturation colour. In the literature one finds over 100 whiteness formulas. The most practical whiteness formula is the one developed by E. Ganz (see appendix). Ganz ratings correlate with the CIBA GEIGY scale as follows: GANZ rating -20 5 25 50 70 90 105 130 150 175 185 210 Appendix

CIBA-GEIGY scale 1 2 3 4 5 6 7 8 9 10 11 12

Fluorescence is a form of luminescence, the emission of radiation in the form of light when an electron changes from a state of higher energy to a lower state. In fluorescence this is caused by absorbed radiation, mostly ultraviolet followed by emission in longer, visible wavelengths. Luminescence covers fluorescence and phosphorescence, fluorescence lifetimes being from 10-6 to 10-9 second, phosphorescence lifetimes being from 10-4 to 10-2 second. For measurement of these phenomena a well defined light source is important, i.e. constant output and constant spectral characteristic. Three types of standard light sources have been defined: A, C, D65. For FTM 20 only source type D65 is of interest, as it approximates average daylight with a colour temperature of 6500K. It emits sufficient ultraviolet to induce fluorescence of optical brighteners.

Light sources

1. For a first approximation, natural daylight may be used instead of a standard light source. However, daylight varies in colour temperature and intensity. 2. Artificial daylight sources such as those available from HERAEUS provide a much more constant source approximating D65. 3. Light cabinets are offered on the market, having lamps with different dominant wavelengths, E.S. 254 nm and 360 nm. With such a cabinet one can observe the activity of different optical brighteners. 4. When the purpose is to test fluorescence as such, without a basic whiteness of the material (for instance, a transparent film overprinted with fluorescent ink), an ultraviolet source should be used, normally a UV-A source with 380 nm dominant wavelength.

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5. The best source for testing whiteness is a standard D65 source used under the standard lighting conditions of an Ulbricht integrating sphere. Also, the UV spectrum of the source (generally a flash tube) needs to be calibrated. These requirements are fulfilled in instruments such as the Datacolor Elrepho 2000 and similar instruments from other suppliers. Test Equipment See Section 2 of this Handbook. Ganz whiteness formula Judgement of neutral whiteness varies from person to person. That is why in the GANZ formula (or Ganz-Griesser formula) W=(D.Y)+(P.x)+(Q.y)+C where Y, x, y are luminance or luminosity and chromaticity coefficients or tristimulus reflectance factors, GANZ parameters D, P, Q, C are introduced. They reflect the judgement of the majority of observers. Literature 1. E. Ganz, Whiteness: photometric specification and colorimetric evaluation. Appl. Optics 15 (1976) 9 pp 2039-2058. 2. Rolf Griesser (1979), Methods and uses of colorimetric evaluation of paper. CIBA-Geigy pamphlet 7009, pp 25-29. Fluorescent marking standard negotiations are going on in the labelling industry to establish a standard for fluorescent identification of labels, to ensure optimal detection by an appropriate luminescence probe. Enquiries: Mr Peter Haas, Product Manager Automation, Erwin Sick AG, tel: +49 – 7681 – 2023271, fax: +49 – 7681 – 2023609. Issued March 1999 Revised May 2001

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FTM 21

FINAT Test Method no. 21 Ink Adhesion - basic

Scope

This method allows rapid assessment of the degree of adhesion of a printing ink or lacquer to a labelstock.

Definition

The printing ink or lacquer is applied to the substrate and cured on the printing press or using a standard method appropriate for the type of ink. The ink adhesion is then estimated by the amount of ink that can be removed when adhesive tape is applied and peeled off. The resistance of the ink to mechanical removal is also measured by scratching the ink and by deformation under pressure.

Test Equipment

A means of applying and curing the ink. Adhesive tape of high peel adhesion ('aggressive’), for example Tesa 7475 (acrylic based), Tesa 7476 (rubber based), or 3M Scotch 810. FINAT roller to smooth the tape over the test piece. Metal spatula. Gloves.

Test Pieces

If the required ink has not already been applied to the substrate as part of the printing process, prepare samples for testing by coating the ink to a uniform thickness (for example, with a Meyer bar for low-viscosity inks) and curing the coating as recommended by the supplier. A-4 sheets are a conveniently-sized sample for this test. Test condition 23°C ± 2°C and 50 % RH ± 5% RH. If practical, the test pieces should be conditioned for at least four hours prior to testing.

Procedure

1. Tape test Lay the specimen on a smooth, flat, hard surface and apply the adhesive tape, leaving a small part of the tape unfixed to the test piece, ensuring that no air bubbles are trapped under the tape. Using the FINAT roller, press down the tape by ing the roller twice in each direction over the specimen, and then bend the unattached part of the tape back on itself at an angle of 180°. Within 20 minutes after rolling down the tape, mount the specimen in a frame or use one hand to hold the specimen firmly, then pull the free piece of tape towards you using the other hand: at first slowly under constant speed, then very rapidly and accelerating. (The faster speed is the more aggressive test).

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The performance of the specimen is recorded by comparison with control samples which have been previously measured, or by reference to the following grading: Grade 1 No removal of ink Grade 2 Slight removal of ink (< 10%) Grade 3 Moderate removal of ink (10 - 30%) Grade 4 Severe removal of ink (30 - 60%) Grade 5 Almost complete removal of ink (> 60%) 2. Mechanical tests • Scratch test Place the test piece against a firm, flat backing, and rub a blunt metal implement (for example, a spatula) back and forth over the test piece until the ink starts to be removed from the substrate. Record the number of rubs required to fail the sample, and compare this to standard samples to determine if the sample es or fails. Note: an instrument should be chosen which does not cut the ink (a printer's knife is not suitable) and which is consistent between operators (a fingernail is not). • Rub test Place the test piece against a firm, flat backing, and press your thumb firmly onto the test piece and twist it back and forth. Compare the test piece with previously-assessed control samples to determine if the piece has ed. Note: it is recommended that appropriate Health & Safety measures are taken in case the ink is insufficiently cured. Notes

1. The presence of waxes and silicones in some inks and varnishes can result in poor adhesion between the adhesive tape and the ink surface, and consequently the tape is unable to separate ink from the substrate even when the adhesion is poor, leading to a false ‘’ result. To address this risk, it is recommended to adopt both a tape test and another method of testing ink adhesion when evaluating unfamiliar inks. 2. Different batches of the same adhesive tape can have very different peel strengths (in excess of the minimum specified), and therefore give difference results on the same print, so a possibly false "fail" can arise. For rigorous work, or where ink adhesion is critical, it is recommended to calibrate new lots of tape by testing them on printed samples of known performance before testing unknown samples. 3. If a numerical result from the adhesive tape test is required, the percentage adhesion can be obtained by using a cross-hatching tool to score the ink into 2 mm squares before applying the tape, and then measuring the number of squares remaining after the tape test is performed. The cutting tool needs to be constructed to cut entirely through the ink layer but through no more than a small fraction of the substrate, otherwise tear of the substrate will occur.

Issued March 1999 Revised June 2001

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FTM 22

FINAT Test Method no. 22 Ink Adhesion - advanced

Scope

This method allows rapid assessment of the degree of adhesion of a printing ink or lacquer to a labelstock. It is designed for the testing of digital print media.

Definition

The printing ink or lacquer is applied to the substrate and cured on the printing press or using a standard method appropriate for the type of ink. The ink adhesion is then estimated by the amount of ink that can be removed when adhesive tape is applied and peeled off.

Test Equipment

A means of applying and curing the ink. Adhesive tape of high peel adhesion ('aggressive'), for example Tesa 7475 (acrylic based), Tesa 7476 (rubber based), or 3M Scotch 810. A standard FINAT test roller. A tensile tester or similar machine, capable of peeling a laminate through an angle of 180° at a jaw separation rate of 300 mm per minute and with an accuracy of ± 2%. Spectrophotometer, e.g. X-Rite DTP22, Datacolor Elrepho 3000, Hunterlab Ultrascan XE.

Test Pieces

The ink is brought onto the substrate. After that, a certain period of time has to be taken into consideration, to make absolutely sure that the ink is completely hardened and/or dry. If the print system works with a one or more colour system, it is preferred that the adhesion of the pure colours is evaluated, and not that of a combination of colours. The adhesion of the ink can be evaluated by measuring the colour before and after the application of the adhesive tape. The amount of ink that has been removed can be expressed, in ∆E, by the colour change measured by the spectrophotometer, on the ink coated sample before and after application of the adhesive tape.

Test condition

23°C ± 2°C and 50 % RH ± 5 % RH. If practical, the test pieces should be conditioned for at least four hours prior to testing.

Procedure

1. Tape test Lay the specimen (30 mm by 175 mm) on a smooth, flat, hard surface and apply the adhesive tape, ensuring that no air bubbles are trapped under the tape. Using the FINAT roller, press down the tape by ing the roller twice in each direction over the specimen, and then bend the unattached part of the tape back on itself at an angle of 180°. Fix each strip in the machine, so that the tape can be stripped away from the printed substrate at an angle of peel of 180°. Set the machine to operate at 300 mm/min jaw separation rate.

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Evaluation

The peel value is expressed as the average result for the strips tested in Newton per 25 mm. The peel force gives an indication of the force that has affected the ink and an approximate measurement of the adhesion of an overlaminate to the ink. The colour is measured on the printed substrate before and after removing the tape. The colour difference is expressed in ∆E. ∆E measurements can be rated as: ∆E = 0 - 3 Excellent ∆E = 3 - 5 Very good ∆E = 5 - 10 Good ∆E = 10 - 15 Acceptable ∆E = 15 - 20 Poor ∆E = 20 - 25 Unacceptable

Remark

This test is based on FTM 21.

Note

The presence of waxes and silicones in some inks can lead to false "" results. Therefore it is important to mention the peel adhesion value.

Issued June 2001

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FTM 23

FINAT Test Method no. 23 Die - Strike

Scope

This test method allows the converter to assess the degree and consistency of die strike and cutting during the conversion process. The method can be used during press make ready to assess the condition and settings of cutters, to prevent label dispensing failures or web breaks during high speed dispensing. The test is applicable to paper based liners.

Definition

The display, by use of a green water based dye, of silicone or paper damage caused by die cutting.

Test Equipment

Malachite Dye Electronic Balance 1 litre measuring cylinder Latex Gloves Cotton Swabs Sample Bath Clean Water Clock

Test Pieces

The test specimen should be at least one complete width and repeat of the cutter.

Test Conditions

No special conditions apply.

Procedure

Preparation of Malachite Solution Take a 1 litre container (a capped polyethylene bottle is suitable). Place the container on an electronic balance. Wearing latex gloves and taking care not to spill or touch the dye, weigh carefully 1 gram of Malachite into the container. Measure out 1 litre of distilled water using a measuring cylinder and add to the container. Shake the bottle to dissolve the dye stuff. 1. Quick - End Of Press Test Remove the labels from the die cut sample. Wet the swab liberally with the Malachite Solution. With the swab, wipe the silicone surface of the liner where the labels have been with the swab. Wipe off the excess solution with a dry swab and assess the die cutting.

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2. Formal Assessment - Laboratory Conditions Wearing latex gloves: Prepare two baths of appropriate size, one containing not more than 1 cm height of the prepared Malachite Solution and one of clean water. Slowly delaminate and/ remove labels from the die cut sample under evaluation. Take care not to damage /or crease the liner in any way. With each hand take the ends of the sample and float it silicone side down on the surface of the Malachite Solution. Take care that the Malachite Solution does not make with the reverse side of the liner. Allow the sample to remain in with the solution for 30 seconds and then remove the sample. Allow the Malachite Solution to drain back into the bath. Place the sample silicone side down in the clean water bath and agitate to remove any remaining Malachite Solution. When washed, remove and place the sample between any suitable paper materials to dry e.g. tissue paper or cotton wool swab. Results

Assess the die strike pattern for intensity and consistency. Look at the reverse side of the liner for complete penetration. There should be no signs of Malachite penetration through the backing. The deeper the visible die cutting, the greater the risk of the adhesive adhering into the backing, this which will cause the label to failure to dispense. Excessive visible damage of the paper can also give rise to liner breaks. Retain samples indicating acceptable results in envelopes to traceability. Malachite may fade when exposed to a strong light source. To avoid this problem, electronic scanning and storage of the image may be used.

Safety

Avoid any direct skin with the Malachite Solution. Always wear gloves.

Notes

Malachite Solution should be stored in a well-closed container and away from direct day light. Storage life is about 1 month. Alternative dye chemicals could be used , eg. crystal violet.

Issued May 2001

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FTM 24

FINAT Test Method no. 24 Mandrel Hold

Scope

This test is used to determine the ability of a pressure sensitive adhesive to adhere to cylindrical curved surfaces.

Definition

Mandrel adhesion is defined as the edge lifting (expressed in mm) of pressure sensitive adhesive coated material from standard cylindrical rod / tubes of small diameter, after being applied with light finger pressure for a specified amount of time.

Test Equipment

Rack to tubes/rods without having between test samples and ing rack. Rods/tubes of 8mm and 15mm diameter (the diameter of the mandrel should be representative of the end-use). Rods/tubes made of glass and polyethylene. Other materials and diameters may be used as necessary, and reported as such. The results of the tests are very much dependant of the face materials used. These materials need to be well identified and their specification well known.

Test pieces

The test piece dimensions should be adapted so that the length of the sample label covers 3/4 of the circumference of the test tube/rod. The width of the sample should be half of the length of the label. Examples: 10 mm x 20 mm for a 8 mm diameter tube/rod 15 mm x 35 mm for a 15 mm diameter tube/rod Test pieces should be cut in the machine direction AND in the cross direction. 3 test pieces should be taken from material sample. Cuts should be clean and straight. Test standard conditions: Test pieces should be conditioned at 23°C ± 2°C and 50 % ± 5 % RH during at least 16 hours before being cut. Other conditions might be used, but this must be clearly reported.

Procedure

Use new test materials for any new test. Clean the glass tubes/rods with acetone or other suitable solvent (heptane…) before using them, to avoid any deposit, grease or dust. Other tubes/rods not made from glass should be used such as supplied. Avoid to touch them with fingers before any test. Remove the backing from the face material avoiding curling of the face material, and touching the adhesive surface. Apply the sample around the tube/rod with the long side of the sample perpendicular to the axis of the rod/tube. Put some light finger pressure to obtain sufficient adhesion/ between the whole adhesive coating area and the test tube/rod. (It may be easier to cut the label longer than needed and to trim the excess of label sample at time of application on the tubes/rods) The labelled tubes/rods are inspected after 1 week. The edge lifting if any, is measured in mm at each side of the label (l1, l2). Edge lift is the total length of each label no longer in with the test tube/rod divided by 2, e.g.: (l1 + l2)/2.

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59

Results

Report identification of the samples and test tubes/rods materials. Calculate and report the mean value of the 3 tests for the edge lift measurement described above for each sample/testing material, and the time evolved since application of the face material. Describe the type of failure (AF, CF, AT). Failure Description Code CF Cohesive Failure - the adhesive film is split during the test, leaving residue of adhesive on both the and the front material. AF Adhesive Failure - the adhesive separates cleanly from the front material, leaving adhesive film on the test sample. AT Adhesive Transfer - the adhesive separates cleanly from the front material, leaving adhesive film on the test . The approximate extent of transfer should be quoted as percentage Indicate any deviations from above procedure.

Note:

Specific application equipment can be used to reduce variation of results due to “light finger” application procedure.

Issued May 2001

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FINAT Technical Handbook 6th edition, 2001

SECTION 2

Test equipment

2.1 Standard FINAT Test Roller Performance requirements for this test roller are that it applies a standard pressure irrespective of the variation in hand pressure on the handle. Specifications

Diameter of roll: mm 85 ± 2.5 Roll cover: rubber to hardness scale Shore A 80 ± 5 Width of roll: mm 50 ± 1 Weight of roller: kg 2 ± 0.05 Rollers made to the earlier specifications 92 – 98 mm diameter are still acceptable.

2.2 Automatic Rolling Device The FINAT automatic roller unit ensures correct guidance of the roll and electronic adjustment of the rolling speed. The number of roll movements can be set at between 1 and 9 by a selector switch. The roll can easily be taken from its mounting. Rolls to other standards can also be used. The roll can also be safely lifted from the substrate in the end position. Technical data

Roller speed 3 levels 5, 10, 200 (± 1 %) mm/s Length of roll area adjustable max 300mm Mains connection 220 V/50 or 110V/60

Roll data

Diameter: mm 85 ± 2.5 Width: mm 50 ± 1 Weight: kg 2 ± 0.05 Hardness of rubber surface: Shore A 80 ± 5 Thickness of rubber layer: mm 6 ± 0.5 Rolls can be supplied to other standards

2.3 Sources of test equipment Test equipment is available in a wide variety. A number of manufacturers of such equipment are listed below, where possible with an indication of the type of their equipment. Please check the FINAT website (www.finat.com) frequently for updates. Adhesive Technical Services Beacon Hill Industrial Estate PO Box 51 Purfleet, Essex RM19 1SY United Kingdom Tel. +44 – 1708 – 867 355 Fax. +44 – 1708 – 869 804

Agent for Sneep Industries BV (see below)

Beiersdorf AG Unnastrasse 48 D-20245 Hamburg Tel. +49 – 40 – 4909-0 Fax. +49 – 40 - 49093434

tesa test tapes 7475 and 7476 (FTM 10, 11) see also list of agents world-wide below

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61

Büro Mayr Forststrasse 81 D-85521 Riemerling Tel. +49 – 89 - 609 9679 Fax +49 – 89 – 609 8436

High Speed Release Tester, Standard Test Roller

ChemInstruments Inc. (FTM 1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 14, 15, 18, 21) Part of the Chemsultants Intl. Network 9349 Hamilton Drive Mentor, Ohio 44060 U.S.A. Tel. +1 – 440 – 352 - 0218 Fax +1 – 440 – 352 - 8572 URL: www.cheminstruments.com European sales agents: Adhesive Technical Services, Erichsen, ICHEMCO Datacolor AG Brandbachstrasse 10 CH-8305 Dietlikon/Zürich Switzerland Tel. +41 – 1 – 835 3711 Fax +41 – 1 – 835 3739

Colour Measurement (FTM 20, FTM 22)

Erwin Sick AG D-79183 Waldkirch Tel: +49-7681-202 3271 Fax: +49-7681-202 3609

Colour Measurement (FTM 20)

Epprecht Instruments + Controls AG Am Hägli 7 oder Neu Am Hägli 27 CH-5605 Dottikan Switzerland Tel. +41 – 57 – 242 419

Viscosity Tester

Erichsen Am Iserbach 14 D-58675 Hemer Tel. +49 – 2372 - 9683-0 Fax +49 – 2372 - 6430 Email: [email protected] URL: www.erichsen.de

Tensile Testers Adhesion Testers Humidity Cabinets Thickness Gauges Agents: Chemsultants Int. Network

Frank Weinheimerstrasse 6 D-69488 Birkenau bei Weinheim Tel. +49 – 6201 – 84-0 Fax +49 – 6201 – 84-290

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Tensile Tester, Adhesion Tester

FINAT Technical Handbook 6th edition, 2001

Hunter Associates Laboratory 11491 Sunset Hills Rd Reston, VA 20190-5280 U.S.A. Tel. +1 - 703 - 471 - 6870 Fax. +1 - 703 - 471 - 4237

Colour Measurement (FTM 20, FTM 22)

Imass Inc. P.O. Box 134 Accord, MA 02018-0134 U.S.A. Tel. +1 – 781 – 982 8096 Fax +1 – 781 – 982 9647 Email: [email protected] URL: www.imass.com

High Speed Release Tester

Instron Wolpert GmbH Landwehrstrasse 55 64293 Darmstadt Tel. +49 – 6151 – 324600 Fax +49 – 6151 - 324699 Email: [email protected] URL: www.instron.com

Tensile Tester, Adhesion Tester

Klemmt Mess- und Prüftechnik GbR Plinganserstrasse 40a D-81369 München Tel. +49 – 89 – 7472 460 Fax +49 – 89 – 7472 4622 Email: [email protected] URL: www.klemmt.de

Agent Sneep Industries BV (see below)

Köttermann Industriestrasse 2-10 D-31311 Uetze-Hänigsen Tel. +49 – 5147 – 760 Fax +49 – 5147 – 7650

Humidity Tester

Laetus am Sandberg Geratebau GmbH Postfach 1262 D-64660 Alsbach-Hahnlein Tel: +49 – 6257 – 50090 Fax: +49 – 6257 - 5009260

Colour Measurement (FTM 20, FTM 22)

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63

Lorentzen & Wettre GmbH Machtifinger Strasse 24 D-81379 München Tel. +49 – 89 – 785 004-0 Fax.+49 – 89 – 785 004-43 URL: www.lorentzen-wettre.com

Paper testing equipment

MB+S Wilhelmstrasse 8 D-32602 Vlotho Tel. +49 – 5733 – 91000 Fax +49 – 5733 – 910050 Email: [email protected]

Barcode Readability Tester

Metorex International Oy Email [email protected] For a list of distributors see www: metorex.com

X-ray spectrometers (XRF) (FTM7) OES Analyzers

Minolta (Schweiz) AG Riedstrasse 6 CH-8953 Dietikon Switzerland Tel. +41 – 1 – 740 3727 Fax +41 – 1 – 742 2350 Email: [email protected] URL: www.minolta.ch

Colour Measurement

MTS Systems Rue Auguste Perret F-94200 Creteil Tel. +33 – 1 – 58439000 Fax +33 – 1 – 58439020

Tensile Testers for release, tack and peel Specimen cutters, rollers

Oxford Instruments Halifax Road, High Wycombe, Bucks HP12 3SE United Kingdom Tel. +44 – 1494 – 442 255 Fax +44 – 1494 – 524 129 Email: [email protected] URL: www.oxford-instruments.com

X-ray spectrometers (XRF) (FTM7)

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FINAT Technical Handbook 6th edition, 2001

Pausch Messtechnik Nordstrasse 32 D-42781 Haan Tel. +49 – 2129 - 6004 Fax +49 – 2129 - 1012

Q-Sun and QUV weathering Testers Outdoor Weathering Sevices Colour Measurement

Pearson Panke Equipment Ltd. 1-3 Halegrove Gardens London NW7 3LR United Kingdom Tel. +44 – 020 – 89593232 Fax +44- 020 – 89595613 Email: [email protected] URL: www.pearsonpanke.co.uk

Special Tensile Testers: 0 0 Release (FTM 3),180 Peel (FTM 1), 90 (FTM 2), Loop tack (FTM 9) Shear Testers FTM 8 for ambient and oven shear testing Hand Rollers Rolling Ball Tack Testers O Meter for surface wetting properties Viscometers Rub Testers Gloss meters Colourmeters and Spectrophotometers

Printech Tools & Technology Schoosswiesen 14 CH-9225 Wilen Gottshaus Switzerland Tel. +41 – 71 – 422 5152 Fax +41 – 71 – 422 5153 Email: [email protected]

Standard FINAT Test Roller Special Peel, Release and Tensile Testers (FTM 1, 2, 3, 8, 9, 10, 11) Print Resistance Spot Proofer (FTM 16) UV Light Spectrometer (to check UV curing and Exposure units for exact wave length and intensity)

Rambold Messgeräte GmbH Am Krebsgraben 18 D-78048 VS-Villingen Tel. +49 – 7721 – 8003-0/8003-57 Fax +49 – 7721 – 8003-20

Dynamic Cohesion

Sick AG Industrial Sensors Seb. Kneippstrasse 1 D 79183 Waldkirch Tel. +49 - 7681 – 2023271 Fax +49 - 7681 – 2023609 Email: [email protected]

Fluorecense Measurement

Sneep Industries BV P.O. Box 5726 NL-3290 AA Strijen The Netherlands Tel . +31 – 78 – 610 76 90 Fax. +31 – 78 – 610 76 91 Email: [email protected] URL: www.sneepindustries.com

Shear testers, hotmelt/holding power at elevated temperature High and low speed peel and release testers Hand rollers, test plates of ss and glass Automatic roll down machine FTMs 1, 2, 3, 4, 5, 8 and 9 Custom built testers

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SPECTRO Analytical Instruments GmbH. & Co. KG Boschstrasse 10 D-47533 Kleve Tel. +49 – 2821 – 8920 Fax +49 – 2821 – 892 – 2200 Email: [email protected] URL: www.spectro-ai.com

X-ray spectrometers (XRF) (FTM7)

Weiss Greizenstrasse 41-49 D-35447 Reiskirchen-Lindenstruth Tel. +49 – 6408 – 84-0 Fax. +49 – 6408 – 84-341

Humidity Tester

X-Rite Ltd. Acumen Centre First Avenue Poynton, Cheshire SK 121 FJ UK X-Rite Inc. 3100 44th street S.W. Grandville Michigan 49418 USA

X-Rite Equipment to FTM 22

Zwick GmbH & Co. Prüfmaschinen August Nagelstrasse 11 D-89079 Ulm Tel. +49 - 7305100 Fax +49 - 730510200 Email: [email protected] URL: www.zwick.de

Tensile Tester

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FINAT Technical Handbook 6th edition, 2001

tesa world-wide

FINAT approved test tapes Australia Beiersdorf Australia Ltd. 90-94-Warren Road Smithfield, N.S.W. 2164 Tel.: **61-2/9681 30 44 Fax: **61-2/9892 39 78

Colombia BDF Colombia S.A. Apartado Aéreo 7983 Cali Tel.: **57-2/6510 200 Fax: **57-2/654 02 17

India tesa Tapes (India) Pvt.Ltd. Plot No. L-14, M.I.D.C., Taloja, Dist. Raigad-410208 Tel.: **91-22/740 21 53 Fax: **91-22/740 21 55

Norway Beiersdorf A/S PB 16 Leirdal N-1008 Oslo 10 Tel.: **47-22/90 79 50 Fax: **47-22/32 55 03

Argentina Beiersdorf S.A. Triunvirato 2902 1427 Buenos Aires Tel.: **54-11/4553 00 40 Fax: **54-11/4553 01 03

Czech Rep. Beiersdorf spol. s.r.o. Pekarská 14 CS-15500 Praha 5 Tel.: **420-2/228 29 540 Fax: **420-2/228 29 549

Paraguay Beiersdorf S.A. Paso de Patria No. 3162 Asunción Tel./Fax: **595-21/55 53 58

Austria Beiersdorf Ges mbH Postfach 179 A-1101-Wien Tel.: **43-1/6140 00 Fax: **43-1/61 40 03 20

Denmark Beiersdorf A/S Klintehøj Vaenge 12 DK-3460 Birkerød Tel.: **00420-2/22 82 95 40 Fax: **00420-2/22 82 95 49

Indonesia tesa tape Asia Pacific Pte. Ltd. Sastra Graha Bldg. 6th floor - suite 603 Jl.Raya Pejuangan No. 21 Jakarta 11530 Tel.: **62-21/535 88 09 Fax: **62-21/535 88 08

Belgium SA Beiersdorf NV Boulevard Industriel 30 B-1070 Bruxelles Tel.: **32-2/526 52 11 Fax: **32-2/526 52 19

Ecuador Fábrica Nacional de Adhesivos Co. Ltda. Avenida 6 de Diciembre 3467 y Bélgica P.O.B. 17-12-222 Quito Tel.: **593-2/44 18 97 Fax: **593-2/44 18 96

Bolivia Beiersdorf SRL Av. Las Américas #136 Santa Cruz Tel.: **591-3/37 69 28 Fax: **591/911 36 61 Chile BDF Chile SA 13 393 Correo Central Santiago, Chile Tel.: **56-2/557 36 66 Fax: **56-2/557 38 83 China Beijing: tesa tape (HK) Ltd. Room 102 Gan De Office Building No.11, Beisanhuanxi Road Haidian District Beijing 100088 Tel.: **86-10/623 88 751 Fax: **86-10/623 88 716 Hong Kong: tesa tape (HK) Ltd. Shui On Centre Room 2601-3 8, Harbour Road Wan Chai, Hong Kong Tel.: **852/25 83 99 80 Fax: **852/25 98 92 44 Shanghai: Beiersdorf (Shanghai) Trading Company Ltd. Room 601 Astronautic Building (North) 222 Caoxi Road Shanghai 200233 PRC Tel.: **86-21/6482 088 Fax: **86-21/6482 0689

Finland Beiersdorf Oy PL/Box 91 FIN-20101Turku/Abo Tel.: **358-2/410 32 00 Fax: **358-2/410 32 70 Beiersdorf S.A. 1, rue de Sources F-77176 Savigny le Temple Tel.: **33-1/64 87 30 00 Fax: **33-1/64 87 30 10 Great Britain Beiersdorf UK Ltd. Yeomans Drive, Blakelands GB-Milton Keynes, Bucks MK 14 5LS Tel.: **44-1908/21 13 33 Fax: **44-1908/21 15 55 Greece Beiersdorf Hellas AE P.O.Box 60 001 GR-15310 Ag. Paraskevis/ Athens Tel.: **30-1/660 01 00 Fax: **30-1/661 23 44 Guatemala BDF Centroamérica S.A. Apartado Postal 2084 Guatemala (GCA) Tel.: **502/476 25 25 Fax: **502/476 23 90 Hungary Beiersdorf Kft. Tartsay Vilmos U.3 H-1126 Budapest Tel.: **36-1/457 39 00 Fax: **36-1/457 39 01

FINAT Technical Handbook 6th edition, 2001

Island J. S. Helgason H.F. P.O.B. 10055 IS-130 Reykjavik Tel.: **354-1/68 51 52 Fax: **354-1/67 44 52 Italy Beiersdorf Spa Casella Postale 17094 I-20170 Milano Tel.: **39-02/25 77 21 Fax: **39-02/25 77 22 70 Japan Beiersdorf Japan K.K. No. 15. Arai Bldg. 6-19-20 Jingumae Shibuya-ku Tokyo 150-0001 Tel.: **81-3/57 78 62 41 Fax: **81-3/57 78 62 49 Korea tesa tape (HK) Ltd. Whawon Building, 6th Fl. 746-1 Yeoksam-Dong, Kangnam-ku Seoul 135-080 Tel.: **822/569 84 51 Fax: **822/569 84 55 Malaysia tesa tape (Malaysia) Sdn Bhd. No. 16-1, First Floor Jalan 1/149D Bandar Baru Seri Petaling 57000 Kuala Lumpur Tel.: **60-3/959 57 66 Fax: **60-3/959 64 66 Mexico BDF México S.A. de C.V. Apartado Postal 15-067 02300 México D.F. Tel.: **52-5/729 02 00 Fax: **52-5/587 72 78 Netherlands Beiersdorf N.V. Postbus 3003 NL-1300 ED Almere Tel.: **31-36/538 91 00 Fax: **31-36/538 94 70

Philippines tesa tape Asia Pacific Pte. Ltd. 2170 Garrido Street, Santa Ana Manila Tel.: **63-2/563 73 95 Fax: **63-2/563 73 95 Peru Beiersdorf S.A. Apartado 708 Lima 100 Tel.: **51-14/521 26 55 Fax: **51-14/85 08 40 Poland Beiersdorf - Lechia S.A. ul.Chlebowa 4/8 PL-60-960 Poznan Tel.: **48-61/8746 100 Fax: **48-61/877 05 87 Portugal Beiersdorf Portuguesa Lda. Apartado 9 P-2746 Queluz Codex Tel.: **351-1/436 85 00 Fax: **351-1/436 28 74

South Africa Buffalo Tapes P.O.B. 43380 Industria 2042 Johannesburg Tel.: **27-11/474 14 88 Fax: **27-11/474 80 15 Sweden Beiersdorf AB Box 10056 S-43421 Kungsbacka Tel.: **46-300/550 00 Fax: **46-300/129 32 Switzerland Bandfix AG Industriestr. 19 CH-8962 Bergdietikon Tel.: **41-1/744 31 11 Fax: **41-1/741 26 72 Taiwan Beiersdorf AG Branch Office Taiwan 17F - 1, 33 Min Sheng Road Sec. 1, Pan Chiao City Taipei Hsien Tel.: **886-2/2957 9662 Fax: **886-2/2957 9433 Thailand tesa tape Asia Pacific Pte. Ltd., 252/94, 17 th Floor Muang Thai-Phatra Office Tower 2 Rachadaphisek Road, Huaykwang Bangkok 10320 Tel.: **66-2/693 2678 Fax: **66-2/693 2680

Russia Beiersdorf AG Office Prospekt Mira 33, Building 1, Olympic Plaza Business Center GUS 129110 Moskau Tel.: **7-095/258 4023 Fax: **7-095/258 40 27

Turkey Beiersdorf Kimya Sanayi ve Ticaret A.S. Plaza Spring Giz Is Merkezi Büyükdere Cad. Meydan Sk. No. 102/1 80670-Maslak-Istanbul Tel.: **90-212/286 18 70 Fax: **90-212/286 18 77

Singapore tesa tape Asia Pacific Pte.Ltd. 164 Gul Circle, Singapore 629621 Tel.: **65/861 20 26 Fax: **65/863 81 40

USA tesa tapes inc. 5825 Carnegie Boulevard Charlotte, N.C. 28209 Tel.: **1-704/554 07 07 Fax: **1-704/553 56 53

Spain Beiersdorf S.A. Ctra. de Mataró a Granollers, P. Km. 5,4 E-08310 Argentona (Barcelona) Tel.: **34-93/758 33 00 Fax: **34-93/758 34 44

Uruguay Beiersdorf S.R.L. Cuareim 1844 - Oficina 1 11800 Montevideo Tel.: **598-2/924 08 20 Fax: **598-2/924 99 94 Venezuela Beiersdorf S.A. Avenida Romula Gallegos Torre Poliprima Piso 6, Oficina A Santa Eduvigis Caracas Tel.: **58-22/85 74 59 Fax: **58-22/85 60 94

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SECTION 3

Recommended s in self-adhesive laminates for roll labels

Conversion It is important that a in a self adhesive laminate should be made in such a way that it will minimise problems when converted into roll labels. The should be angled so that the feed-in is gradual, the width of facing tape and backing tape should differ so that there is not too great a step in increased thickness and the total thickness of the should be kept to a minimum in order to avoid damage to or misplacement of the cutters. The following specification is recommended: a) The angle of the should be 10° - 30° from the cross direction. b) The width of tape on the facing paper should be at least 18 mm. c) The width of tape on the backing paper should be greater than the width of tape on the facing paper and should be at least 36mm. d) The tapes should have a thickness of no more than 0.063mm inclusive of adhesive. e) The tape used on the backing paper should be a coloured tape for ease of identification but the tape on the facing paper can either be a coloured tape for a similar reason, or a white printable tape for use with laminates which are to be converted to security or sequentially numbered labels, i.e. when all labels must be ed for. f) Where applicable the tapes should withstand the temperatures involved in label printing processes. Issued October 1985 Revised March 1999

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SECTION 4

Processing recommendations

Roll stock 1. Generally, self-adhesive paper roll stock can be considered as normal paper with respect to ink choice etc. Vinyl, filmic and foil roll stock, however often need special materials involving consultation with ink suppliers. 2. Always check with the Supplier if his material can withstand the intended process conditions, particularly if excessive temperatures or unusual webfeed patterns are involved. 3. Do not change the winding direction of the roll prior to conversion, as this will alter the release lamination and may create curl problems. 4. Always use the correct die for the product. The die should always be checked for damage prior to start up. Standard double bevelled dies are recommended for paper products. Band steel bevelled dies should be made with the bevel towards the wastage to prevent crushed label edges. 5. Labels should be designed with matrix stripping in mind. Refer to the supplier if complex shapes are involved. Wherever possible, use round corners for labels and avoid narrow matrices.

8. Where heat is necessary use the minimum necessary to achieve satisfactory matrix stripping. Excessive heat (which can be easily induced by the use of hot plates) may create adhesive stringing, fouling of the labels and heat build up in the reel. Always try to work to a fixed setting, paying particular attention to returning to it after exceptional amounts of heat have been used. 9. Avoid excessive tension in reels of finished labels. This will prevent bleeding. 10. Wind finished labels on to cores of an appropriate size. Large labels should not be wound on to small cores. 11. Finished work should be shrouded in polythene prior to packing. 12. Wherever possible, the manufacturer’s batch/order references should be retained in case of complaints.

Revised May 2001

6. Check the depth of die-cutting before proceeding with any lengthy run. Always avoid inconsistencies. Excessive die pressure will cause weakening of the backing paper and should be avoided in products intended for high speed automatic application. With heat set inks, use the minimum amount of heat necessary for ink curing. Avoid winding up hot reels. 7. With UV cured inks, always check the cure before proceeding. Checks should be made on the age and output of the lamps involved.

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Filmic sheet stock

Paper sheet stock

1. Check that the ink is compatible with the product to be used and is approved or recommended by the ink supplier.

1. Self-Adhesive paper sheet stock can be considered as normal paper with respect to ink type, dryers, retarders, etc.

2. Allow sufficient unprinted edge trim on the screen to prevent edge lift due to shrinkage.

2. When using self-adhesive sheet stock in offset litho printing, however the following points should be noted: a) Reset the impression nip between the blanket and plate cylinder to allow for the extra thickness. This will reduce problems of tail edge creasing, mis etc. b) The double sheet trip should always be used to prevent any damage to plates, etc. c) Always use minimum of damping to prevent edge waving, etc. d) To prevent edge curl, always shroud sheets in polyethylene between colours if multi-colour machines are not being used.

3. Avoid excessive amounts of thinners or retarders to prevent shrinkage. 4. Ensure that all machinery in the vicinity of solvent fumes is fitted with anti-static devices and solvent extractors where possible. 5. Use a minimum of heat to dry the ink in order to avoid sheet curl. 6. When using a jet drier for multi-colour runs, shroud the sheets in polythene between runs to prevent sheet curl. 7. When rack drying, avoid changes in temperature or humidity between runs to prevent sheet curl. 8. Always allow sufficient time between es for each colour to dry. This is of particular importance in the case of flood coating. 9. Print successive close- colours as soon as possible after each other. Printing separate colours under different atmospheric conditions will cause difficulties with .

3. Finished work should be shrouded in polyethylene until cut and boxed. 4. The Manufacturer's recommendations on guillotining and slitting should be used. 5. Wherever possible, retain the Manufacturer's batch/order references in case of complaint. Source: PSMA Issued May 1987

10. Finished work should be shrouded in polythene until cut and boxed. 11. Always follow the Manufacturers recommendations on guillotining and slitting. 12. Wherever possible, retain the Manufacturer's batch/order references in case of complaint.

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SECTION 5

Surfaces requiring caution

Caution should be exercised when labelling surfaces listed below. In many cases products are available which will overcome the problems of application and you are strongly recommended to your material supplier or the PSMA secretariat. Surfaces where damage can be caused by application or removal of self adhesive products Plastics, e.g. plasticisers, PVC., polystyrene, Perspex. Weaker bonded surface finishes e.g. flock coated fabric, acrylic vehicle paint, paper, card. Animal skins and natural fibres, e.g. suede, leather wool. Tarnishable metal surfaces, e.g. copper brass, silver. Some glass surfaces, e.g. optical lenses. Surfaces to which it is difficult to obtain satisfactory adhesion Low energy surfaces where 'wetting' is difficult e.g. PT.F.E., untreated polyolefins, silicone treated or contaminated surfaces, surfaces chemically treated for corrosion resistance, waxed surfaces, printed polyethylene (polyamide inks), greasy surfaces. Surface energy changes due to migration or loss of effectiveness of pre-treatment.

Applications where specific advice should be sought Direct food labelling, toy labelling, medical applications, e.g. direct skin , blood bags, sterilisation processes fabric labelling, promotional gimmicks, flag days, extreme environment exposure e.g. temperatures 80°C or -20°C, direct/continuous exposure to UV, seawater exposure, solvent laden atmospheres. Applications involving any surface where damage can be caused by application or removal of self adhesive products as detailed above. Applications involving any surfaces listed as difficult.

See also Section 8 Adhesion problems

Source: PSMA Issued March 1987 Revised May 2001

Rough surfaces where surface is likely to be low, lacquered finishes, cork, foam, open weave fabrics, embossed finishes, unglazed pottery. Moist and/or cold surfaces where adhesive tack will be momentarily deadened by either water or the low temperature e.g. surfaces with condensation bloom, ice, deep frozen food packs. Irregular shaped surfaces in particular curved surfaces of less than 25 mm diameter where label is applied to the convex surface (phials, ampoules, bottle miniatures). Dusty or friable surfaces where adhesive tack may be destroyed on surface , e.g. plaster asbestos, rusty metal. Surfaces prone to gassing (caused by undercure) which if it occurs after label application, may lead to eventual bond failure, e.g. polycarbonate, fibreglass, sealant. Ageing Surfaces where adhesive may be significantly exposed to the atmosphere resulting in eventual breakdown and failure of the adhesive, e.g. drum labelling.

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SECTION 6

Safety guide for s of selfadhesive label stock products

Waste laminate is usually classified in most countries as "non-hazardous" but local and national regulations must be examined and complied with. The following points should be noted:

Storage

Fire

Normal storage principles should be applied when storing and stacking laminate rolls. Materials involved are generally flammable and therefore should be stored away from all sources of heat and ignition. Consideration should be given to listing types of material stored to assist the Fire Brigade in the event of fire.

The laminates will burn in the event of with a flame, smoky fumes being given off by the adhesive itself. Fires may be extinguished with water provided that live electrical equipment is not in the vicinity, if not powder or C02 should be used - the advice of your Fire Officer should be initially sought having regard for the layout of your premises and the particular operations involved. The following extra precautions are applicable to the products stated.

Usage 1. Handling Safe methods of roll and pallet handling should be applied. When unbanding pallets, care should be exercised to avoid whiplash when banding is cut – eye protection and gloves are recommended. It is important to that the outside wrappers, or laps, of a roll are for protection only and should not be relied upon to the roll if excessive stresses are applied. Ideally, lifting and movement should be conducted in a safe horizontal manner using centre core where possible. Operators should be forewarned that self adhesive laminate rolls show a greater tendency to telescope than rolls of plain paper and therefore greater care should be exercised. 2. Conversion Care should be taken to avoid cuts from exposed paper of laminate edges during handling. During the conversion of pressure sensitive laminates static build up may occur and, therefore, conversion equipment should be adequately earthed. In situations where highly flammable solvents or inks are being used, specialist recommendations on static elimination may be necessary.

72

1. Films Plastic films through a melt stage and will therefore drip before burning - this may cause severe burns if skin is made. In the event of a fire, the use of self contained breathing apparatus is recommended during fire-fighting. 2. PVC (vinyls) During combustion, hydrochloric acid gas is evolved, as well as dense smoke and other acrid fumes which can have a corrosive and irritant effect. Self contained positive air breathing equipment should be readily available for fire fighting and rescue work.

Health Under normal conditions of handling, no hazards are anticipated but good industrial hygiene should always be observed. For specialised applications e.g. food, toy or surgical labelling, advice should be sought from the individual supplier.

FINAT Technical Handbook 6th edition, 2001

Waste disposal

Other information

Waste laminate is usually classified in most countries as non-hazardous" but local and national regulations must be examined and complied with.

The Technical Department of the Supplier should be ed for any additional specific information required.

The following points should be noted: i) Vinyl laminate should only be considered for incineration if the incinerator is suitably constructed to cope with corrosive fumes and dense smoke, and operates under conditions that prevent the formation of dioxins. ii) Acrylic adhesive based laminates should only be incinerated if the incinerator can cope with corrosive flue gases. iii) If the adhesive contains aluminium powder filler notice of this should be give prior to incineration. iv) Incineration of aluminium foil laminate is not recommended due to possible blocking of the incinerator.

Source: PSMA Issued January 1987 Supplement FINAT Waste Management Systems issued December 1995 Revised March 1999

While research and development efforts continue towards material recycling solutions, FINAT has arranged waste disposal systems in a number of countries for laminates and release liners. For laminate waste, these systems are based on high temperature combustion as a fuel in the cement industry and in power stations. The systems include provision for collection, shredding and transport and require long term commitment. For release liner there are possibilities for material recycling, provided the waste is clean. In and The Netherlands, a separate collection scheme for release liner waste is available to label converters and s. Such schemes can only be set up and implemented in a collective approach for the industry. For information, the FINAT Secretariat.

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SECTION 7

Handling and storage of label stock

Roll stock

Sheet Stock

Receipt of goods On receiving goods into premises, inspect packages or drums for signs of damage. Inform supplier of any shortage or damage immediately. Store all material on a clean dry floor. Where goods are supplied on pallets, it is advisable to retain the material on these until needed. Rolls should be stored on end in supplier's original packaging until required. Slit reels should have been interleaved by the supplier. Reels stored on their side may pressure mark or produce a flat if stored for long periods.

Receipt of goods Sheets are normally received packaged flat. Prior to putting into stock, inspect for damage. Transport material to storage area ed on a flat base to prevent bending or flexing as this can permanently distort the laminate.

Storage conditions Whenever possible, do not unwrap rolls until required. Avoid extremes of temperatures and humidity: conditions should be ideally those of the print shop. (Ideal conditions would be between 20-22°C and 50 - 55% RH). High temperatures could induce adhesive bleed and cause strike through. Fluctuations in humidity could cause cockles and wavy edges. Materials should not be stored near to sources of heat and ignition, or in direct sunlight.

Storage Conditions Sheets should be kept in supplier's packaging until required. Store under stable temperature and humidity conditions which should preferably be those of the print shop (ideal conditions would be between 20-22°C and 50 - 55% RH). Stack height should be minimal. Materials should not be stored near to sources of heat and ignition or in direct sunlight.

Preparation of material for processing Transport material carefully from storage. Retain moisture-proof wrapping and allow to attain print or process room temperature for at least 24 hours before processing. Handling cold material in a shop with normal temperatures may cause wavy edges and curling. If material requires slitting before processing, ensure blades/knives are clean and sharp. Avoid rewinding too tight since this may cause adhesive bleed. Slit coils should be stacked on end, interleaved and shrouded in polythene.

Preparation of material for processing If storage conditions are not ideal, the material should be allowed to condition (still in the wrapper) for at least 48 hours at printing room conditions. Failure to condition sheets at print room conditions may create curling or wavy edges due to variations in temperature/humidity. If sheets require cutting for printing, then the knife of the guillotine should be very sharp with the flattest possible bevel edge. Freshly cut sheets of vinyl should be given the opportunity to shrink and stabilise prior to printing. Cut the minimum number of sheets practicable, referring to the manufacturer for advice if necessary. Use minimum pressure to avoid adhesive bleed. Vinyls, polyesters and acetate are best cut face down. If stacks are left overnight, protect from temperature and humidity changes by shrouding with polythene. Before printing full or cut sheets, fan them out, and in cases where there is excessive bleed, wipe the edges with cotton wool which has been sparingly dusted with talcum powder.

Storage and Handling of finished product Store in a cool, dry place. Stock finished coils on end, interleaved with release coated clips of paper to avoid blocking. Pack in polythene cartons or drums for despatch.

Storage and Handling of finished product Store in a cool, dry place. Collate finished sheets and pack in polythene. Pack flat ensuring adequate rigidity. Take care, if banding, to avoid pressure marking.

Pay particular attention to the supplier's recommended shelf-life and ensure correct stock rotation.

Source: PSMA Issued April 1987 Revised March 1999

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SECTION 8

Adhesion problems

From time to time printers may encounter adhesion problems and these can be expensive as they occur after labels have been printed. It is recommended that printers carry out a simple adhesion check before proceeding with new business, using specific self adhesive laminates. Recommended adhesion test 1. Cut out several labels, same size and in the same grain direction as the proposed printed label. 2. Peel off backing and apply to object to be labelled in the same position as the eventual requirement. Rub down lightly with fingers or a rubber pad. 3. Ideally, prepare several samples and place one in a dry atmosphere and one in high humidity. 4. Leave for 24 hours minimum before assessment of adhesion.

Release testing This property is difficult to test without special equipment. Generally speaking, if labels can be produced on converting equipment at normal speeds, without either the skeleton breaking or labels dispensing, then the end will have no problems. Where butt-cut labels or sheets are used, hand delamination using a jerk and snatch action will give an indication of possible tight release. Source: PSMA 1987 Revised March 1999

Assessment of adhesion 1. Examine visually for edge lift. 2. Lift up corner of the label and peel with a firm, slow pull. 3. Good adhesion should result in at least 30% fibre tear (by area) in the label paper. Filmic labels can only be assessed by the peel force required to remove the label. Removable labels can be tested in the same way, but should not give any fibre tear or surface damage when removed. Surfaces to be labelled 1. Surfaces may not be what they appear to be. For example glass may have a protective coating or antiscuff agent on the surface. There is no substitute for a test carried out on the actual object to be labelled. 2. Test for adhesion under conditions which are as close as possible to the end . 3. Do not carry out the test on a flat, empty plastic bag when the end is labelling one filled with product. 4. Check whether the label is to be applied to a plain or a printed part of the pack. 5. On plastic or filmic surfaces, materials that can migrate to the surface may be present. Advice should be sought from suppliers since these materials can have a detrimental effect on adhesion.

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SECTION 9

Removal of adhesives or adhesive labels

It is imperative that the following paragraphs are read before consulting the tables overleaf. Methods To remove adhesives or adhesive labels several possible methods can be used. The following sequence of methods is recommended: a) Attempt to peel the label away slowly b) Soak in hot water containing detergent. Remove label by gentle rubbing or scraping. This method is only suitable for substrates unaffected by water and/or detergent. c) Removal of label using household solvent, e.g. lighter fuel, methylated spirits, white spirit. Caution: It is necessary to check resistance of substrate against solvent attack. Carry out test on unexposed area. d) Strong solvents (see notes on handling strong solvents below and the tables). e) Gentle scraping: often satisfactory for paper labels. Scraping may be necessary prior to methods b) and c) where filmic/foil labels have been applied, i.e. to break label surface. Caution is required on sensitive/weak substrates. f) For filmic products it may be possible to peel off the label using a hot air gun. Alternatively, failing label removal by household solvents, soaking in solvents such as isopropyl acetate, toluene, acetone or MEK should be considered but it is advised that beforehand recommendations be sought from the label stock manufacturer.

Handling strong solvents The following tables deal with STRONG solvents, some are highly flammable and none should be inhaled, therefore: i) ii) iii) iv) v) vi)

USE IN A WELL VENTILATED AREA DO NOT SMOKE KEEP AWAY FROM NAKED FLAMES WEAR PROTECTIVE CLOTHING – PARTICULARLY EYES AND HANDS USE A PROPRIETORY BARRIER CREAM READ CAREFULLY THE TECHNICAL NOTIFICATION SUPPLIED BY THE SOLVENT MANUFACTURER

It is very important to identify the surface in question correctly, reference to the manufacturer can be made. Even so, always check a small area first, in some place where minor damage will not be important. Source: PSMA 1987

Effectiveness of solvents Both types of hydrocarbon solvents will in most cases dissolve the adhesive, the aromatic type being the most effective. Most of the aliphatic solvents on sale contain small proportions of the aromatic type therefore it is often difficult to predict accurately the effect on the surface in question. Therefore: USE CAUTION.

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Label Application Surface Type Some Trade Names

Solvent Effectiveness Good ***/Medium**/Poor* A = safe to use/B = caution/C = do not use *** Aliphatic Hydrocarbons Gasoline White Spirit Varsol 40 Exsol D40

*** Aromatic Hydrocarbons Toluene Xylene

* Alcohols

*** Ketones

Ethanol IMS (Industrial Methylated Spirits)

Acetone MEK (Methyl Ethyl Ketone)

Lustran Novodur Cycolac Ampcolite

A

X

A

X

X

Epoxy Resins

Araldite Epon

A

A

A

A

A

Melamime Resins

Melatine Memac

A

A

A

A

A

Polyamides (Nylon)

Akulon

A

A

A

A

A

Polychloroprene

Neoprene

A

X

A

B

X

Polyesters

Hostaphan Melinex Mylar

A

A

A

A

A

Polyethylene (Polythene)

Escorene PE Lactene Lupolen

A

B

A

A

B

PLASTICS Acrylonitrile Butadiene Styrene (ABS)

** Chlorinated Hydrocarbons Carbon Tetrachloride Dichloromethane

Polyformaldehyde

Celon

(UF or MF)

Delrin

A

A

A

A

A

PolymethylMethacrylate

Plexiglass Perspex

A

X

X

X

X

Polypropylene

Escorene PP Hostalen PP Moplen

B

B

A

A

B

Polystyrene

Lustrex Styron

X

X

A

X

X

Polytetrafluorethylene (PTFE)

Teflon

A

A

A

A

A

Polyurethanes

Desmodur Desmophen

A

X

B

B

B

Polyvinylchloride rigid (PVC)

Lucoflex

A

X

A

X

B

Soft PVC - vinyl

B

X

X

X

X

Polycarbonat

Lexan

B

X

A

X

X

Polyphenylene Oxide (PPO)

Noryl

X

X

A

X

X

RUBBERS Butyl

X

X

A

B

X

Natural or SB rubber (SBR)

X

X

A

B

X

Silicone

X

X

B

X

X

Alkyd

Typical surfaces Woodwork doors etc.

B

X

B

X

X

Cellulose & Thermoplastic

Cars

B

X

A

X

B

A

B

A

B

X

PAINTS

Acrylics Stove Enamel and cross linked acrylics

Domestic Appliances

A

B

A

B

X

Varnished surfaces

Polished wood

B

X

B

X

X

(as the formulation of varnishes can vary greatly, use extreme caution) OTHERS Fabrics

These are frequently complex polymers and often mixtures of natural and synthetic fibres. Use caution, starting with the least aggressive solvents

Glass

A

Leather

All solvents attack and shrink leather - use extreme caution

A

A

A

Metal

A

A

A

A

Wood

A

A

A

A

A

Key to the tables: A - safe to use subject to conditions on page overleaf; B - use with caution. Could damage in some cases, or with prolonged ; X - do not use. Please note that this list is presented only as a guide and is not comprehensive.

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SECTION 10 Adhesives

Pressure sensitive adhesives were first developed in the mid nineteenth century for self-adhesive bandages. However, it was only ninety years later that the idea was used to make self-adhesive labels. The adhesive used was made from natural rubber and applied by coating from a solvent solution. Although the product adhered well to a wide range of surfaces, its ageing properties were not good, and the need to use large quantities of solvent in the coating process was a disadvantage.

The subsequent introduction of acrylic adhesives overcame some of the shortcomings. Acrylics had excellent ageing properties and were also available as water-based emulsions. The water-based products were easy to coat and clearly eliminated the hazards linked with solvent coating. Recently hot melt adhesives have been introduced. These adhesives can be coated at very high speeds and very high coating weights, because there is no drying process involved.

Types for specific applications Permanent

An adhesive with high ultimate adhesion, where labels are not intended to be removed. Available from standard to very high coating weights, depending on the end application.

Removable, Peelable

An adhesive with a low ultimate adhesion to a wide range of surfaces. Careful choice of adhesive must be made, particularly for surfaces like fabrics, paper and plastic films.

Water Removable

An adhesive which, upon with water, will have a reduced adhesive bond, allowing clean removal.

Water Soluble

An adhesive which is completely soluble in water.

Low Temperature

An adhesive capable of functioning at temperatures below + 5°C, i.e. chill conditions (+ 5°C to-5°C), deep freeze conditions (-5°C to-25°C) and blast freeze conditions (-25°C to -50°C).

Frosted Surface

An adhesive for application to goods which are already frozen.

High Temperature, Heat Resistant

An adhesive capable of retaining its properties when used at high temperatures.

Light Stable, UV Stable

An adhesive for use with clear films where labels will be exposed to direct sunlight.

Water Resistant

An adhesive where labels are subjected to high humidity or immersion in water.

Plasticiser Resistant

An adhesive which, when applied to PVC or other plastics containing plasticisers, maintains an acceptable level of performance.

Pigmented Adhesive

An adhesive used for over-labelling or masking heavily printed or coloured surfaces.

Re-positionable

An adhesive which permits removal and repositioning shortly after application, prior to the development of ultimate adhesion.

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Textile, Fabric, Garment

An adhesive designed for application to textiles. It may be permanent or removable in type, according to specific applications. Careful choice of adhesive must be made particularly for sensitive materials, e.g. suede, PVC, silk.

Marine Approved

An adhesive laminate construction, which complies with BS 5609, Adhesive Coated Labels for Marine Use.

Food

An adhesive with the appropriate F.D.A., B.g.V.V. or other appropriate approval for application to foodstuffs.

Weather Resistant

An adhesive for use where labels are subjected to a variety of external conditions.

Odour and taint Pressure sensitive adhesives are manufactured primarily from polymers and resins and are selected to meet the challenging requirements of conversion and end adhesion performance. Different adhesives will have a retained odour level characteristic of their chemical type, but components are selected to ensure that the odour level is minimised and, wherever possible, will be generally recognised as safe by virtue of prior industrial experience or compliance with legislation concerning labelling. Since various foods will respond differently to different odours, the final assessment of tainting due to residual odour should be judged by the end concerned

Source: PSMA

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SECTION 11 Unwind roll chart

Indicate unwind direction by number as follows

Extract from TLMI Manual of Recommended Standards (where the chart has 16 positions).

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SECTION 12 Communication of technical data between labelstock manufacturer and label printer In June 1991, the European Pressure Sensitive Manufacturers’ Association (EPSMA) published the EPSMA Roll Label and Pallet Label Standard. This standard enables manufacturers of self-adhesive laminates to adopt a common method of bar coding, which can be scanned and read by both laminate manufacturer and converter. Label converters across Europe can confidently introduce scanning systems in the knowledge that all major labelstock suppliers have adopted the EPSMA standard. This initiative has added opportunities for scanning during the printing operation to bring additional efficiencies to production: ●

● ● ●

Better handling of stocks of adhesive materials and finished products Traceability for ISO 9000 Better inventory management Less mistakes in shipments

A 10-minute video demonstrating the benefits of bar coding for a converter is available free of charge in English, French, German, or Spanish, from the FINAT Secretariat.

●

● ●

● ● ●

Basic data: giving product code data on the selfadhesive construction -- face, adhesive and backing (see figure 1) Physical construction: for function, size, shelf life Technical construction: with application and service temperature, release and peel parameters (see figure 2) Face: for weight, calliper and gloss Adhesive: repeating the product code data Backing: for weight, calliper and transparency

The LAMDATA Access Database currently provides screen-based instructions in seven languages: Danish, Dutch, English, Finnish, French, German and Spanish. Other languages can be added. A number of standard search routines have been provided in the software to enable converters to select products from individual manufacturers, or from the entire database. A free demonstration of the LAMDATA Access Database, with no time or restrictions, is available either from the FINAT Home Page (www.finat.com) or by ordering direct from the FINAT secretariat.

Issued March 1999

The EPSMA/FINAT Laminate Product Database Standard (‘LAMDATA’) This important new industry initiative, adopted in 1996/97, represents the second phase in the development of fully-integrated industry standards. It is a direct response to the dynamic development of electronic dialogue between manufacturer and converter, which identified a need for product data interchange in a format that was universally compatible for both parties. The LAMDATA Standard meets this need, and can be used in its own right to create and update a converter’s internal database, or to provide the basic data to enable bar code scanning to interface more successfully with computer systems. Data complying with the LAMDATA standard format is presented on disk as a data file – but to enable them to be imported into a converter’s computer system, additional software may be required, in the form of the LAMDATA Access Database. This software s all 94 fields specified in the LAMDATA Standard, and the data is presented on six screens (or ‘forms’):

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SECTION 13 Guidelines for accelerated ageing tests Purpose

These guidelines should be used when planning tests for accelerated ageing of selfadhesive laminates. The final test can be anything (e.g. adhesion, migration, release). These guidelines only define the ageing conditions. Prior to testing, the samples should be removed from the ageing cabinet and conditioned to the testing conditions, as described in each test method. Ageing tests are typically carried out for a period of 4 weeks, and the tests are done once a week. The test should always include a previously tested, known product reference. This makes it easier to interpret the results. 1 - Drying oven ageing Typical purpose: testing of adhesive migration Temperature: + 50 degree Celsius Samples kept under pressure of approximately 25g/cm2 (15kg/A4 sheet) 2 - Climate chamber testing Typical purpose: testing of changes in adhesion properties Temperature: + 35 degree Celsius Relative humidity: 75% RH Samples not kept under pressure

Issued May 2001

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