ASTM D6020-00(2016)

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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: D6020 − 00 (Reapproved 2010) D6020 − 00 (Reapproved 2016)
Standard Practice for
Calculation of (Non-Mineral) Combined Tanning Agents and
Degree of Tannage
This standard is issued under the fixed designation D6020; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope
1.1 This practice covers the determination of the combined tannin and nonextractable organic resins and the degree of tannage
of all types of vegetable-tanned leather and leather with organic retannages. This practice does not apply to wet blue.
2. Referenced Documents
2.1 ASTM Standards:
D2868 Test Method for Nitrogen Content (Kjeldahl) and Hide Substance Content of Leather, Wet Blue and Wet White
D2875 Test Method for Insoluble Ash of Vegetable-Tanned Leather
D2876 Test Method for Water-Soluble Matter of Vegetable-Tanned Leather
D3495 Test Method for Hexane Extraction of Leather
3. Significance and Use
3.1 This practice may be used to determine non-protein or non-nitrogen containing organic matter in leather which is not
extractable with water or hexane. Examples would be vegetable tannins and acrylic lubricants.
4. Procedure
4.1 The chloroform and water extractable materials and insoluble ash in the specimen for test shall be determined in accordance
with Test Methods D2875, D2876, and D3495.
4.2 The hide substance in the specimen for test shall be determined in accordance with Test Method D2868.
5. Calculation of Results
5.1 The percentage of combined tannin in the specimen shall be calculated as follows:
Combined tannin, percent 5 100 2 ~A1B1C1D! (1)
where:
A = percent of chloroform-soluble material (mfb),
B = percent of water-soluble material (mfb),
C = percent of insoluble ash (mfb), and
D = percent of hide substance (mfb).
(mfb) = moisture free basis.
5.2 The degree of tannage shall be calculated as follows:
T
Degree of tannage 5 3100 (2)
D
This practice is under the jurisdiction of ASTM Committee D31 on Leather and is the direct responsibility of Subcommittee D31.01 on Vegetable Leather.
Current edition approved April 1, 2010Sept. 1, 2016. Published May 2010October 2016. Originally approved in 1996. Last previous edition approved in 20052010 as
D6020
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