ASTM D6076-03
(Test Method)Standard Test Method for Shrinkage Temperature of Leather
Standard Test Method for Shrinkage Temperature of Leather
SIGNIFICANCE AND USE
5.1 This test method is designed to determine the temperature at which a thoroughly wetted leather specimen experiences shrinkage. In this test method, shrinkage occurs as a result of hydrothermal denaturation of the collagen protein molecules which make up the fiber structure of the leather. The shrinkage temperature of leather is influenced by many different factors, most of which appear to affect the number and nature of crosslinking interactions between adjacent polypeptide chains of the collagen protein molecules. The value of the shrinkage temperature of leather is commonly used as an indicator of the type of tannage or the degree of tannage, or both, of that particular leather (especially for the more hydrothermally stable tannages such as chrome tannage).
SCOPE
1.1 This test method covers the determination of the shrinkage temperature of all types of leather. The heating medium is water when the shrinkage temperature is at or below 98°C. The heating medium is a glycerine-water solution when the shrinkage temperature is above 98°C.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.3 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
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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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D 6076–03
Standard Test Method for
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Shrinkage Temperature of Leather
This standard is issued under the fixed designation D 6076; 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.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope method. This specimen is then fastened between two clamps
(one fixed and one movable) and immersed in the aqueous
1.1 This test method covers the determination of the shrink-
medium. The aqueous medium is gradually heated until the
age temperature of all types of leather. The heating medium is
specified temperature is reached without shrinkage or until
water when the shrinkage temperature is at or below 98°C.The
shrinkage is indicated by a deflection of the dial needle which
heating medium is a glycerine-water solution when the shrink-
is attached to the movable clamp.
age temperature is above 98°C.
1.2 The values stated in SI units are to be regarded as the
5. Significance and Use
standard. The values given in parentheses are for information
5.1 This test method is designed to determine the tempera-
only.
tureatwhichathoroughlywettedleatherspecimenexperiences
1.3 This standard does not purport to address all of the
shrinkage. In this test method, shrinkage occurs as a result of
safety concerns, if any, associated with its use. It is the
hydrothermal denaturation of the collagen protein molecules
responsibility of the user of this standard to establish appro-
which make up the fiber structure of the leather. The shrinkage
priate safety and health practices and determine the applica-
temperature of leather is influenced by many different factors,
bility of regulatory limitations prior to use.
most of which appear to affect the number and nature of
2. Referenced Documents crosslinking interactions between adjacent polypeptide chains
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of the collagen protein molecules. The value of the shrinkage
2.1 ASTM Standards:
temperature of leather is commonly used as an indicator of the
D 1517 Terminology Relating to Leather
type of tannage or the degree of tannage, or both, of that
3. Terminology
particular leather (especially for the more hydrothermally
stable tannages such as chrome tannage).
3.1 Definitions—For definitions of general leather terms
used in this test method, refer to Terminology D 1517.
6. Apparatus
3.2 Definitions of Terms Specific to This Standard:
6.1 Stand, for supporting the testing equipment.
3.2.1 shrink—to contract or become smaller.
6.2 Indicating Device, either of the two devices listed as
3.2.2 shrinkage—the temperature at which noticeable
follows:
shrinkage occurs when a leather specimen is gradually heated
6.2.1 Theis Shrinkage Meter Dial—a dial indicator having a
in an aqueous medium.
face divided into 360 to 380°, with one revolution of the dial
4. Summary of Test Method hand corresponding to 12.7 mm (0.5 in.) of specimen move-
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ment, and with leeway for four revolutions of the dial hand.
4.1 Aleather specimen is thoroughly soaked in the aqueous
6.2.2 AGD (American Gage Design) Dial Indicator—A
medium that will be used to heat the specimen for this test
mechanical device capable of registering on a scale a reading
of the shrinkage or swelling movement of the specimen in a
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This test method is under the jurisdiction ofASTM Committee D31 on Leather
ratio of at least 25 units of dial movement (or greater) to 1 unit
andisthedirectresponsibilityofSubcommitteeD31.07onPhysicalProperties.This
of specimen movement, and shall accurately detect by move-
test method was developed from Federal Test Method Standard No. 311, Method
ment of the dial needle the point at which shrinkage begins.
7011.1, in cooperation with the U.S. Defense Personnel Support Center, Directorate
of Clothing and Textiles, Philadelphia, PA and the U.S. Army Natick Research,
Development and Engineering Center, Natick, MA.
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Current edition approved Oct. 1, 2003. Published December 2003. Originally A shrinkage meter apparatus setup meeting these specific requirements was
approved in 1997. Last previous edition approved in 1997 as D 6076-97. formerly available from theArthur H.Thomas Co., Philadelphia, PA.The minimum
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For referenced ASTM standards, visit the ASTM website, www.astm.org, or number of apparatus setups required for an order makes the cost of new apparatus
contactASTM Customer Service at service@astm.org. ForAnnual Book of ASTM of this type prohibitive. Used apparatus of this type may still be available from
Standards volume information, refer to the standard’s Document Summary page on tanneries or laboratories that have gone out of busine
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