ASTM F88/F88M-15

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.  
4.1.1 The 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 either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
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: 31-Oct-2015
• ICS: 55.040 - Packaging materials and accessories
• Technical Committee: F02 - Primary Barrier Packaging
• Drafting Committee: F02.20 - Physical Properties

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: F88/F88M − 15
Standard Test Method for
1
Seal Strength of Flexible Barrier Materials
This standard is issued under the fixed designation F88/F88M; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) 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 Thistestmethodmeasurestheforcerequiredtoseparate zerototheforcelevelrequiredtopeelthesealisnotindicative
a test strip of material containing the seal. It also identifies the ofsealstrength,anddatafromthatpartofthecurveshouldnot
mode of specimen failure.
be included in the calculation of average strength, nor should
the return to zero following complete failure of the specimen.
1.5 The values stated in either SI units or inch-pound units
The amount of data actually discarded on each end of the
are to be regarded separately as standard. The values stated in
measured seal-profile curve must be the same for all tests
each system may not be exact equivalents; therefore, each
within any set of comparisons of average seal strength (see
system shall be used independently of the other. Combining
6.1.1 and 9.8.1).
values from the two systems may result in non-conformance
with the standard.
3.1.2 flexible, adj—indicates a material with flexural
1.6 This standard does not purport to address all of the strengthandthicknesspermittingaturnbackatanapproximate
safety concerns, if any, associated with its use. It is the
180 degree angle.
responsibility of the user of this standard to establish appro-
3.1.3 maximum seal strength, n—maximum force per unit
priate safety and health practices and determine the applica-
width of seal required to separate progressively a flexible
bility of regulatory limitations prior to use.
material from a rigid material or another flexible material,
under the conditions of the test.
2. Referenced Documents
2
2.1 ASTM Standards:
4. Significance and Use
D882Test Method for Tensile Properties of Thin Plastic
Sheeting
4.1 Sealstrengthisaquantitativemeasureforuseinprocess
E171Practice for Conditioning and Testing Flexible Barrier
validation, process control, and capability. Seal strength is not
Packaging
only relevant to opening force and package integrity, but to
E691Practice for Conducting an Interlaboratory Study to
measuring the packaging processes’ ability to produce consis-
Determine the Precision of a Test Method
tent seals. Seal strength at some minimum level is a necessary
package requirement, and at times it is desirable to limit the
3. Terminology
strength of the seal to facilitate opening.
3.1 Definitions:
4.1.1 Themaximumsealforceisimportantinformation,but
for some applications, average force to open the seal may be
1
ThistestmethodisunderthejurisdictionofASTMCommitteeF02onFlexible
useful, and in those cases also should be reported.
Barrier Packaging and is the direct responsibility of Subcommittee F02.20 on
Physical Properties.
4.2 A portion of the force measured when testing materials
Current edition approved Nov. 1, 2015. Published December 2015. Originally
may be a bending component and not seal strength alone. A
approved in 1968. Last previous edition approved in 2009 as F88/F88M–09. DOI:
10.1520/F0088_F0088M-15.
number of fixtures and techniques have been devised to hold
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
samples at various angles to the pull direction to control this
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
bending force. Because the effect of each of these on test
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. resultsisvaried,consistentuseofonetechnique(TechniqueA,
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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F88/F88M − 15
FIG. 1 Tail Holding Methods
Technique B, or Technique C) throughout a test serie
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM 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/F88M − 09 F88/F88M − 15
Standard Test Method for
1
Seal Strength of Flexible Barrier Materials
This standard is issued under the fixed designation F88/F88M; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) 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 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 either SI units or inch-pound units are to be regarded separately as standard. The values stated in each
system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the
two systems may result in non-conformance with the standard.
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:
D882 Test Method for Tensile Properties of Thin Plastic Sheeting
E171 Practice for Conditioning and Testing Flexible Barrier Packaging
E691 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.
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 June 15, 2009Nov. 1, 2015. Published July 2009December 2015. Originally approved in 1968. Last previous edition approved in 20072009 as
F88 – 07a.F88/F88M – 09. DOI: 10.1520/F0088_F0088M-09.10.1520/F0088_F0088M-15.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM 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.
3.1.1.1 Discussion—
The average force normally is calculated by the testing machine from the digitized plot of force versus grip 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—indicates a material with flexural strength and thickness permitting a turn back at an approximate 180 degree
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.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
F88/F88M − 15
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 The 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.
...