Standard Test Method for Tearing Strength on Nonwoven Fabrics by the Tongue (Single Rip) Procedure (Constant-Rate-of-Extension Tensile Testing Machine)

SCOPE
1.1 This test method covers the measurement of the tearing strength of nonwoven fabrics by the tongue (single rip) procedure using a recording constant-rate-of-extension (CRE) tensile testing machine.
1.1.1 The CRE-type tensile testing machine has become the preferred test apparatus for determining tongue tearing strength. It is recognized that some constant-rate-of-traverse (CRT) tensile testing machines continue to be used. As a consequence, these test instruments may be used when agreed upon between the purchaser and the supplier. The conditions for the CRT-type tensile tester as used with this test are included in Appendix X1.
1.2 This test method applies to most nonwoven fabrics including those that are treated or untreated, including those heavily sized, coated or resin treated, provided that during the test, the fabric does not tear in the direction crosswise to the direction of the force applied. This test method may not be useful for highloft nonwoven fabrics. If the tear is not substantially lengthwise, the fabric shall be described as untearable in that direction by this test.
1.3 Tongue tear strength as measured in this method is the maximum single-peak force required to continue or propagate a tear started previously in the specimen. The reported value includes the simultaneous force required to shift fibers, break fibers, break fiber bonds and break fiber interlocks in nonwoven fabric. The reported value is not directly related to the force required to initiate or start a tear.
1.4 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses may be approximate.
1.5 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.

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ASTM D5735-95 - Standard Test Method for Tearing Strength on Nonwoven Fabrics by the Tongue (Single Rip) Procedure (Constant-Rate-of-Extension Tensile Testing Machine)
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NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: D 5735 – 95
Standard Test Method for
Tearing Strength on Nonwoven Fabrics by the Tongue
(Single Rip) Procedure (Constant-Rate-of-Extension Tensile
Testing Machine)
This standard is issued under the fixed designation D 5735; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope D 76 Specification for Tensile Testing Machines for Tex-
tiles
1.1 This test method covers the measurement of the tearing
D 123 Terminology Relating to Textile Materials
strength of nonwoven fabrics by the tongue (single rip)
D 1776 Practice for Conditioning Textiles for Testing
procedure using a recording constant-rate-of-extension (CRE)
D 4848 Terminology Relating to Force and Deformation
tensile testing machine.
and Properties Textiles
1.1.1 The CRE-type tensile testing machine has become the
preferred test apparatus for determining tongue tearing
3. Terminology
strength. It is recognized that some constant-rate-of-traverse
3.1 Definitions:
(CRT) tensile testing machines continue to be used. As a
3.1.1 lengthwise direction, n—in textiles, the direction in a
consequence, these test instruments may be used when agreed
machine-made fabric parallel to the direction of movement the
upon between the purchaser and the supplier. The conditions
fabric followed in the manufacturing machine.
for the CRT-type tensile tester as used with this test are
3.1.1.1 Discussion—For nonwovens, an easily distinguish-
included in Appendix X1.
able pattern for orientation may not be apparent, especially if
1.2 This test method applies to most nonwoven fabrics
removed from the roll. Care should be taken to maintain the
including those that are treated or untreated, including those
directionality by clearly marking the direction.
heavily sized, coated or resin treated, provided that during the
3.1.2 nonwoven fabric, n—a textile structure produced by
test, the fabric does not tear in the direction crosswise to the
bonding or interlocking of fibers, or both, accomplished by
direction of the force applied. This test method may not be
mechanical, chemical, thermal, or solvent means and combi-
useful for highloft nonwoven fabrics. If the tear is not
nation thereof.
substantially lengthwise, the fabric shall be described as
3.1.3 tearing force, n—the average force required to con-
untearable in that direction by this test.
tinue a tear previously started in a fabric.
1.3 Tongue tear strength as measured in this method is the
3.1.3.1 Discussion—For nonwovens, the tearing force is
maximum single-peak force required to continue or propagate
recorded as the maximum force required to continue a tear
a tear started previously in the specimen. The reported value
previously started in a fabric. The tearing force may appear as
includes the simultaneous force required to shift fibers, break
a single peak or a series of peaks on a force-extension curve,
fibers, break fiber bonds and break fiber interlocks in non-
depending on the nature of the material. Typically for non-
woven fabric. The reported value is not directly related to the
woven fabrics, if a small decrease in force occurs at a time
force required to initiate or start a tear.
when the applied force is increasing, it is not considered as a
1.4 The values stated in SI units are to be regarded as the
peak unless the indicated force exceeds the force required to
standard. The inch-pound units given in parentheses may be
break, individually or collectively, the fibers, fiber bonds, or
approximate.
fiber interlocks. Lower shifts corresponding to fiber movement
1.5 This standard does not purport to address all of the
do not qualify as peaks since the fibers, fiber bonds, or fiber
safety concerns, if any, associated with its use. It is the
interlocks are not broken. The tongue tearing force may be
responsibility of the user of this standard to establish appro-
calculated from a single-peak or multiple-peak force-extension
priate safety and health practices and determine the applica-
curve.
bility of regulatory limitations prior to use.
3.1.4 tearing strength, n—the force required either to start
2. Referenced Documents or to continue or propagate a tear in a fabric under specified
conditions.
2.1 ASTM Standards:
3.1.5 widthwise direction, n—in textiles, the direction in a
This test method is under the jurisdiction of ASTM Committee D-13 on Textiles
and is the direct responsibility of Subcommittee D13.64 on Non-Woven Fabric. Annual Book of ASTM Standards, Vol 07.01.
Current edition approved June 15, 1995. Published September 1995. Annual Book of ASTM Standards, Vol 07.02.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
D 5735
machine-made fabric perpendicular to the direction of move- strength of the fibers, fiber bonds, or fiber interlocks, individu-
ment the fabric followed in the manufacturing machine. ally or in combination, needed to stop a tear in a fabric of the
3.1.6 For other definitions of other textile terms used in this same construction.
test method, refer to Terminology D 123 and Terminology 5.5 Most nonwoven fabrics can be tested by this test
D 4848. method. Some modification of clamping techniques may be
necessary for a given fabric, depending upon its structure.
4. Summary of Test Method
Special adaptation may be necessary with strong fabrics, or
4.1 A rectangular specimen, cut in the center of the shorter
fabrics made from glass fibers, to prevent them from slipping
edge to form a two-tongue (trouser type) specimen. One tongue
in the clamps or being damaged as a result of being gripped in
of the specimen is gripped in the upper jaw and the other
the clamps.
tongue is gripped in the lower jaw of a tensile testing machine.
5.6 The CRE-type is the preferred tensile testing machine.
The separation of the jaws is continuously increased to apply a
This test method allows the use of the CRT-type tensile
force to propagate the tear in a ripping action. At the same time,
machine when agreed upon between the purchaser and sup-
the force developed is recorded. The maximum force to
plier. However, there may be no overall correlation between
continue the tear is calculated from autographic chart record-
the results obtained with the CRT machine and the CRE
ers, or microprocessor data collection systems.
machine. Consequently, these two tensile testers cannot be
used interchangeably unless the degree of quantitative corre-
5. Significance and Use
lation has been established between the purchaser and supplier.
5.1 This test method is used in the trade for acceptance
In any event, the CRE machine shall prevail.
testing of commercial shipments of nonwoven fabrics, how-
6. Apparatus
ever, caution is advised since information about between-
laboratory precision is incomplete. Comparative test as di- 6.1 Tensile Testing Machine, of the constant-rate-of-
rected in 5.1.1 may be advisable.
extension (CRE) type conforming to the requirements of
5.1.1 In case of a dispute arising from differences in Specification D 76 with autographic recorder, or automatic
reported test results when using this test method for acceptance
microprocessor data gathering systems.
testing of commercial shipments, the purchaser and the sup- 6.2 Clamps, having all jaw surfaces parallel, flat, and
plier should conduct comparative tests to determine if there is
capable of preventing slippage of the specimen during a test,
a statistical bias between their laboratories. Competent statis- and measuring at least 25 by 75 mm (1 by 3 in.) with the longer
tical assistance is recommended for the investigation of bias. dimension perpendicular to the direction of application of the
As a minimum, the two parties should take a group of test force.
specimens that are as homogeneous as possible and that are 6.2.1 The use of hydraulic pneumatic clamping systems
from a lot of material of the type in question. Test specimens with a minimum of 50 by 75 mm (2 by 3 in.) serrated or rubber
should then be randomly assigned in equal numbers to each jaw faces having a clamping force at the grip faces of 13 to 14
laboratory for testing. The average results from the two
kN (2900 to 3111 lbf) is recommended. Manual clamping is
laboratories should be compared using the appropriate Stu- permitted providing no slippage of the specimen is observed.
dent’s t-test and an acceptable probability level chosen by the
6.2.2 For some materials, to prevent slippage when using
two parties before testing is begun. If a bias is found, either its jaw faces other than serrated, such as rubber faced jaws, they
cause must be found and corrected or the purchaser and the
may be covered with a No. 80 to 120 medium grip emery cloth.
supplier must agree to interpret future test results in view of the Secure the emery cloth to the jaw faces with pressure sensitive
known bias.
tape.
5.2 The force registered in a tear test is irregular, and as a 6.3 Cutting Die or Template, having essentially the shape
consequence empirical methods have had to be developed to
and dimensions with tolerances of 0.5 % shown in Fig. 1.
obtain usable values related to tear strength. In spite of the
7. Sampling and Test Specimens
empirical nature of the reported values, they are considered to
7.1 Lot Sample—As a lot sample for acceptance testing,
reflect comparative performance of similar nonwoven fabrics
take at random the number of rolls, or pieces, of nonwoven
tested and measured in the same way. No procedure is
fabric directed in an applicable material specification or other
available that can be used with all fabrics to determine the
agreement between the purchaser and the supplier. Consider
minimum tearing strength.
the rolls, or pieces, of nonwoven fabric to be the primary
5.3 For nonwoven fabrics, because the individual fibers are
sampling units. In the absence of such an agreement, take the
more or less randomly oriented and capable of some reorien-
number of nonwoven fabric rolls specified in Table 1.
tation in the direction of the applied force, the maximum
tongue tearing strength is reached when the resistance to
NOTE 1—An adequate specification or other agreement between the
further reorientation is greater than the force required to shift
purchaser and supplier requires taking into account the variability between
and rupture one or more fibers, or the fiber interlocking,
rolls or pieces of fabric and between specimens from a swatch from a roll
simultaneously. The tearing strength is determined primarily by or pieces of fabric to provide a sampling plan with a meaningful
producer’s risk, consumer’s risk, acceptable quality level, and limiting
the bonding or interlocking of fibers in this structure.
quality level.
5.4 Depending on the nature of the specimen, the data
recording devices usually will show the tearing force in the 7.2 Laboratory Sample—For the laboratory sample, take a
form of a single-peak. The highest peak appears to reflect the swatch extending the width of the fabric and approximately 1
D 5735
NOTE 1—All tolerances 60.5 %.
FIG. 1 Template for Cutting and Marking Tongue Test Specimens
TABLE 1 Number of Rolls, or Pieces, of Nonwoven Fabric in the
8. Preparation of Apparatus
Lot Sample
8.1 Set the distance between the clamps at the start of the
Number of Rolls, Number of Rolls or Pieces in Lot Sample
test at 75 6 1mm(3 6 0.05 in.). Select the full-scale force
Pieces in Lot, Inclusive
range of the testing machine such that the maximum force
1to3 all
occurs between 15 and 85 % of full-scale force.
4to24 4
25 to 50 5
8.2 Set the testing speed to 50 6 2 mm/min (26 0.1
over 50 10 % to a maximum of ten rolls or pieces
in./min). When agreed upon between the purchaser and the
supplier, the testing speed may be set to 300 6 10 mm/min (12
6 0.5 in./min).
m (1 yd) along the lengthwise direction from each roll, or
piece, in the lot sample. For rolls of fabric, take a sample that 8.3 Verify calibration of the tensile testing machine as
directed in the manufacturer’s instructions and Test Method
will exclude fabric from the outer wrap of the roll or the inner
wrap around the core. D 76.
7.3 Test Specimens—From each laboratory sampling unit, 8.4 When using microprocessor automatic data gathering
take five specimens from the lengthwise direction and five systems, set the appropriate parameters as defined in the
specimens from the widthwise direction, for each test condition manufacturer’s instructions.
described in 8.1, 8.2, and 8.3, as applicable to a material
9. Conditioning
specification or contract order.
7.3.1 Direction of Test—Consider the long direction as the 9.1 Condition 1, Unspecified Testing Conditioning—No
direction of the test. conditioning is required unless otherwise specified in a mate-
7.3.2 Cutting Test Specimens—Take the specimens for the rial specification or contract order.
measurement of the lengthwise direction from different posi- 9.2 Condition 2, Standard Testing Conditions:
tions across the fabric width. Use the cutting die or template 9.2.1 When specified, precondition the specimens by bring-
described in 6.3 and shown in Fig. 1. Take the specimens for ing them to approximate moisture equilibrium in the standard
the measurement of the widthwise direction from different atmosphere for preconditioning textiles as directed in Practice
positions along the length of the fabric. Cut rectangular D 1776.
specimens 75 by 200 mm (3 by 8 in.). Cut the specimens to be 9.2.2 After preconditioning, bring the test specimens to
used for the measurement of the lengthwise direction, with the moisture equilibrium for testing in the standard atmosphere for
shorter dimension parallel to the widthwise direction. Cut the testing textiles as directed in Practice D 1776 or, if applicable,
specimens to be used for the measurement of the widthwise in the specified atmosphere in which the testing is to be
performed.
direction with the shorter dimension parallel to the lengthwise
direction. Make a preliminary cut 75 mm (3 in.) long at the 9.3 Condition 3, Wet Specimen Testing Conditioning:
center of the 75 mm (3 in.) width as shown in Fig. 1. When 9.3.1 Place the specimens in a container and submerge in
specimens are to be tested wet, take the specimens from areas distilled or deionized water at ambient temperature until
adjacent to the dry test specimens. Label to maintain specimen thoroughly soaked.
identity. 9.3.1.1 The time of immersion must be sufficient to wet out
7.3.2.1 Cut specimens representing a broad distribution the specimens, as indicated by no signi
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