GB/T 22884-2024Leather - Bovine wet blue - Specification (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for standardization work Part 1: Structure and drafting rules for standardization documents" Drafting is required.

This document replaces GB/T 22884-2008 "Leather Specification for Wet Blue Bovine Leather". Compared with GB/T 22884-2008, except for the structure in addition to adjustments and editorial changes, the main technical changes are as follows.

Added the provision that it does not apply to split wet blue leather from cattle (see Chapter 1);

Added "Product Classification" (see Chapter 4);-Added requirements for raw hides and skins (see 5.1); -Changed the provisions on the area ratio of aggregated chrome spots on a single product (see 5.2, 6.2.1 of the 2008 edition); -the shrinkage temperature requirement has been changed (see 5.3, Chapter 3 of the 2008 edition); -Added "Volatile Matter", "Dichloromethane Extract", "Chromium Oxide", "Trichlorophenol", "Hexavalent Chromium" and "Anti-Fungus Properties" Indicator requirements (see 5.3);

Added "Size and Grading" requirements (see 5.4);-Changed the sampling and test specimen preparation requirements (see Chapter 6, Chapter 4 of the 2008 edition); -Added test methods for "volatile matter", "chromium oxide content", "hexavalent chromium" and "anti-mildew performance" (see Chapter 7 and Appendix C);

Added the categories of "factory inspection" and "type inspection" (see 8.2 and 8.3); -Changed the qualification criteria (see 8.3.3, 6.2 of the 2008 edition). -this document is modified to adopt ISO 5433:2022 "Leather - Specification for wet blue bovine leather".

Compared with ISO 5433:2022, this document has many structural adjustments.

See Appendix A.

This document has many technical differences compared to ISO 5433:2022.

A table of these technical differences and their causes is given in Appendix B.

The following editorial changes have been made to this document.

Added Appendix A (Informative) "Comparison of structure numbers between this document and ISO 5433:2022";

Added Appendix B (Informative) "Technical differences between this document and ISO 5433:2022 and their reasons". -

1 Scope

This document specifies the requirements for wet blue cow leather, as well as the rules for inspection, marking, packaging, transportation and storage. It also describes the corresponding sampling and testing procedures.

Sample preparation and test methods.

This document applies to the production, inspection and acceptance of wet blue cattle leather produced primarily through chrome tanning after dehairing.

This document does not apply to cattle split wet blue leather.

2 Normative references

The contents of the following documents constitute the essential clauses of this document through normative references in this document.

For referenced documents without a date, only the version corresponding to that date applies to this document; for referenced documents without a date, the latest version (including all amendments) applies.

In this document.

GB/T 22807 Leather and fur chemical tests—Determination of hexavalent chromium content. Spectrophotometric method (GB/T 22807-2019, ISO 17075-1:2017, MOD) GB/T 22808 Leather and fur chemical tests—Determination of chlorophenols (GB/T 22808-2021, ISO 17070.

2015, MOD)

GB/T 38402 Leather and fur chemical tests - Determination of hexavalent chromium content. Chromatographic method (GB/T 38402-2019, ISO 17075-2:2017, MOD) GB/T 39364 Leather chemical, physical, mechanical and colour fastness tests - Sampling locations (GB/T 39364-2020, ISO 2418:2017, MOD) QB/T 2262 Leather Industry Terminology QB/T 2707 Preparation and conditioning of leather specimens for physical and mechanical testing QB/T 2713 Physical and mechanical testing of leather - Determination of shrinkage temperature QB/T 2716 Preparation of leather chemical test samples QB/T 2717 Leather chemical test - Determination of volatile matter QB/T 2718 Leather chemical tests - Determination of dichloromethane extract QB/T 2720 Leather chemical tests—Determination of chromium oxide (Cr2O3). Titration method QB/T 2724 Leather chemical tests - Determination of pH QB/T 5313 Leather chemical tests—Determination of chromium oxide (Cr2O3). Photometric method QB/T 5314 Leather chemical tests - Determination of chromium oxide (Cr2O3). Atomic absorption spectrometry QB/T 5315 Leather chemical tests-Determination of chromium oxide (Cr2O3). Inductively coupled plasma-atomic emission spectrometry (ICP-OES)

3 Terms and Definitions

The terms and definitions defined in QB/T 2262 apply to this document.