GB/T 40920-2021 Leather—Tests for colour fastness—Colour fastness to cycles of to-and-fro rubbing
1 Scope
This document describes a test method for determining the colour fastness to cycles of to-and-fro rubbing of the surface of a leather by rubbing it to and fro with a felt.
This document is applicable to the testing of colour fastness to cycles of to-and-fro rubbing for leathers of all kinds.
2 Normative references
The following documents contain provisions which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 250 Textiles - Tests for colour fastness - Grey scale for assessing change in colour (GB/T 250-2008, ISO 105-A02:1993, IDT)
GB/T 251 Textiles - Tests for colour fastness - Grey scale for assessing staining (GB/T 251-2008, ISO 105-A03:1993, IDT)
GB/T 6151 Textiles - Tests for colour fastness - General principle of testing (GB/T 6151-2016, ISO 105-A01:2010, MOD)
GB/T 6682 Water for analytical laboratory use - Specification and test methods (GB/T 6682-2008, ISO 3696:1987, MOD)
GB/T 24218.2-2009 Textiles - Test methods for nonwovens - Part 2: Determination of thickness (ISO 9073-2:1995, MOD)
GB/T 39364 Leather - Chemical, physical, mechanical and fastness tests - Sampling location (GB/T 39364-2020, ISO 2418:2017, MOD)
QB/T 2464.23 Determination method for color fastness of leather to perspiration (QB/T 2464.23-1999, eqv ISO 11641:1993)
QB/T 2707 Leather - Physical and mechanical tests - Sample preparation and conditioning (QB/T 2707-2018, ISO 2419:2012, MOD)
QB/T 2724 Leather - Chemical tests - Determination of pH (QB/T 2724-2018, ISO 4045:2008, MOD)
3 Terms and definitions
No terms and definitions are listed in this document.
4 Principle
The surface of the leather specimen is rubbed with pieces of compliant felt under a given pressure for a given number of forward and backward motions. The degree of colour staining of the felt and the change in colour of the leather surface are assessed with grey scales. Any other visible change in, or damage to, the surface of the test specimen is also reported.
5 Apparatus and materials
5.1 Rub fastness test apparatus mainly incorporating the elements specified in 5.1.1 to 5.1.3, and optionally including those described in 5.1.4.
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Foreword I
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Apparatus and materials
6 Sampling and preparation of test specimens
7 Procedure
8 Precision
9 Test report
Annex A (Informative) Structural changes between this document and ISO 11640:
Annex B (Informative) Technical differences between this document and ISO 11640:2018 and their causes
