ASTM F88-07a

Standard Test Method for Seal Strength of Flexible Barrier Materials

SIGNIFICANCE AND USE
4.1 Seal strength is a quantitative measure for use in process validation, process control, and capability. Seal strength is not only relevant to opening force and package integrity, but to measuring the packaging processes' ability to produce consistent seals. Seal strength at some minimum level is a necessary package requirement, and at times it is desirable to limit the strength of the seal to facilitate opening.
4.1.1The maximum seal force is important information, but for some applications, average force to open the seal may be useful, and in those cases also should be reported.
4.2 A portion of the force measured when testing materials may be a bending component and not seal strength alone. A number of fixtures and techniques have been devised to hold samples at various angles to the pull direction to control this bending force. Because the effect of each of these on test results is varied, consistent use of one technique (Technique A, Technique B, or Technique C) throughout a test series is recommended. Examples of fixtures and techniques are illustrated in Fig. 1.
4.2.1 Technique A: Unsupported—Each tail of the specimen is secured in opposing grips and the seal remains unsupported while the test is being conducted.
4.2.2 Technique B: Supported 90° (By Hand)—Each tail of the specimen is secured in opposing grips and the seal remains hand-supported at a 90° perpendicular angle to the tails while the test is being conducted.
4.2.3 Technique C: Supported 180°—The least flexible tail is supported flat against a rigid alignment plate held in one grip. The more flexible tail is folded 180° over the seal and is held in the opposing grip while the test is being conducted.
SCOPE
1.1 This test method covers the measurement of the strength of seals in flexible barrier materials.
1.2 The test may be conducted on seals between a flexible material and a rigid material.
1.3 Seals tested in accordance with this test method may be from any source, laboratory or commercial.
1.4 This test method measures the force required to separate a test strip of material containing the seal. It also identifies the mode of specimen failure.
1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 14-Nov-2007
• ICS: 55.040 - Packaging materials and accessories
• Technical Committee: F02 - Primary Barrier Packaging
• Drafting Committee: F02.20 - Physical Properties

Relations

• Replaced By: ASTM F88/F88M-09 - Standard Test Method for Seal Strength of Flexible Barrier Materials
• Effective Date: 15-Jun-2009

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: F 88 – 07a
Standard Test Method for
1
Seal Strength of Flexible Barrier Materials
ThisstandardisissuedunderthefixeddesignationF 88;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscript
epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 3.1.1 average seal strength, n—averageforceperunitwidth
of seal required to separate progressively a flexible material
1.1 Thistestmethodcoversthemeasurementofthestrength
from a rigid material or another flexible material, under the
of seals in flexible barrier materials.
conditions of the test.
1.2 The test may be conducted on seals between a flexible
3.1.1.1 Discussion—The average force normally is calcu-
material and a rigid material.
lated by the testing machine from the digitized plot of force
1.3 Seals tested in accordance with this test method may be
versus grip travel. The plot starts from zero force after slack
from any source, laboratory or commercial.
has been removed from the test strip. The initial ramp-up from
1.4 This test method measures the force required to separate
zero to the force level required to peel the seal is not indicative
a test strip of material containing the seal. It also identifies the
of seal strength, and data from that part of the curve should not
mode of specimen failure.
be included in the calculation of average strength, nor should
1.5 The values stated in SI units are to be regarded as the
the return to zero following complete failure of the specimen.
standard. The values given in parentheses are for information
The amount of data actually discarded on each end of the
only.
measured seal-profile curve must be the same for all tests
1.6 This standard does not purport to address all of the
within any set of comparisons of average seal strength (see
safety concerns, if any, associated with its use. It is the
6.1.1 and 9.8.1).
responsibility of the user of this standard to establish appro-
3.1.2 flexible, adj—indicates a material with flexural
priate safety and health practices and determine the applica-
strengthandthicknesspermittingaturnbackatanapproximate
bility of regulatory limitations prior to use.
180 degree angle.
2. Referenced Documents 3.1.3 maximum seal strength, n—maximum force per unit
2
width of seal required to separate progressively a flexible
2.1 ASTM Standards:
material from a rigid material or another flexible material,
D 882 Test Method for Tensile Properties of Thin Plastic
under the conditions of the test.
Sheeting
3
D 1898 Practice for Sampling of Plastics
4. Significance and Use
E 171 Specification for Atmospheres for Conditioning and
4.1 Sealstrengthisaquantitativemeasureforuseinprocess
Testing Flexible Barrier Materials
validation, process control, and capability. Seal strength is not
E 691 Practice for Conducting an Interlaboratory Study to
only relevant to opening force and package integrity, but to
Determine the Precision of a Test Method
measuring the packaging processes’ ability to produce consis-
3. Terminology tent seals. Seal strength at some minimum level is a necessary
package requirement, and at times it is desirable to limit the
3.1 Definitions:
strength of the seal to facilitate opening.
4.1.1 The maximum seal force is important information, but
1
This test method is under the jurisdiction ofASTM Committee F02 on Flexible for some applications, average force to open the seal may be
Barrier Packaging and is the direct responsibility of Subcommittee F02.20 on
useful, and in those cases also should be reported.
Physical Properties.
4.2 A portion of the force measured when testing materials
Current edition approved Nov. 15, 2007. Published December 2007. Originally
may be a bending component and not seal strength alone. A
approved in 1968. Last previous edition approved in 2007 as F 88 – 07.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
number of fixtures and techniques have been devised to hold
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
samples at various angles to the pull direction to control this
Standards volume information, refer to the standard’s Document Summary page on
bending force. Because the effect of each of these on test
the ASTM website.
3
Withdrawn. results is varied, consistent use of one technique (TechniqueA,
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

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F88–07a
FIG. 1 Tail Holding Methods
Technique B, or Technique C) throughout a test series is mm (0.984 in.), 15 mm (0.591 in.), or 25.4 mm (1.00 in.).
recommended. Examples of fixtures and techniques ar
...

This document is not anASTM standard and is intended only to provide the user of anASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation:F88–07 Designation: F 88 – 07a
Standard Test Method for
1
Seal Strength of Flexible Barrier Materials
ThisstandardisissuedunderthefixeddesignationF 88;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscript
epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method covers the measurement of the strength of seals in flexible barrier materials.
1.2 The test may be conducted on seals between a flexible material and a rigid material.
1.3 Seals tested in accordance with this test method may be from any source, laboratory or commercial.
1.4 Thistestmethodmeasurestheforcerequiredtoseparateateststripofmaterialcontainingtheseal.Italsoidentifiesthemode
of specimen failure.
1.5 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
D 882 Test Method for Tensile Properties of Thin Plastic Sheeting
3
D 1898 Practice for Sampling of Plastics
E 171 Specification for Atmospheres for Conditioning and Testing Flexible Barrier Materials
E 691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions:
3.1.1 average seal strength, n—average force per unit width of seal required to separate progressively a flexible material from
a rigid material or another flexible material, under the conditions of the test.
3.1.1.1 Discussion—Theaverageforcenormallyiscalculatedbythetestingmachinefromthedigitizedplotofforceversusgrip
travel. The plot starts from zero force after slack has been removed from the test strip. The initial ramp-up from zero to the force
level required to peel the seal is not indicative of seal strength, and data from that part of the curve should not be included in the
calculation of average strength, nor should the return to zero following complete failure of the specimen. The amount of data
actually discarded on each end of the measured seal-profile curve must be the same for all tests within any set of comparisons of
average seal strength (see 6.1.1 and 9.8.1).
3.1.2 flexible, adj—indicatesamaterialwithflexuralstrengthandthicknesspermittingaturnbackatanapproximate180degree
angle.
3.1.3 maximum seal strength, n—maximum force per unit width of seal required to separate progressively a flexible material
from a rigid material or another flexible material, under the conditions of the test.
4. Significance and Use
4.1 Seal strength is a quantitative measure for use in process validation, process control, and capability. Seal strength is not only
relevant to opening force and package integrity, but to measuring the packaging processes’ ability to produce consistent seals. Seal
strength at some minimum level is a necessary package requirement, and at times it is desirable to limit the strength of the seal
to facilitate opening.
4.1.1 Themaximumsealforceisimportantinformation,butforsomeapplications,averageforcetoopenthesealmaybeuseful,
and in those cases also should be reported.
1
This test method is under the jurisdiction of ASTM Committee F02 on Flexible Barrier Packaging and is the direct responsibility of Subcommittee F02.20 on Physical
Properties.
Current edition approved May 1,Nov. 15, 2007. Published JuneDecember 2007. Originally approved in 1968. Last previous edition approved in 20062007 as F 88 – 067.
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Withdrawn.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

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F88–07a
4.2When a seal fails adhesively (peel seal) the value of the bond strength measured is reported.Acohesive failure of the bond,
delamination, or failure elsewhere in the test strip indicates that the substrate, not the seal interface, would be the limiting factor
in the strength of a package. In th
...