GB/T 42164-2022 PDF English
Price & Delivery
US$170.00 · In stock · Download in 9 secondsGB/T 42164-2022: Leather - Chemical tests - Thermal ageing of leather and determination of hexavalent chromium
Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedure
Status: Valid
| Standard ID | USD | BUY PDF | Delivery | Standard Title (Description) | Status |
| GB/T 42164-2022 | 170 | Add to Cart | Auto, 9 seconds. | Leather - Chemical tests - Thermal ageing of leather and determination of hexavalent chromium | Valid |
Click to Preview this PDF
Similar standards
GB/T 42164-2022: Leather - Chemical tests - Thermal ageing of leather and determination of hexavalent chromium
---This is an excerpt. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.), auto-downloaded/delivered in 9 seconds, can be purchased online: https://www.ChineseStandard.net/PDF.aspx/GBT42164-2022
GB NATIONAL STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA ICS 59.140.30 CCS Y 46 Leather - Chemical tests - Thermal ageing of leather and determination of hexavalent chromium (ISO 10195:2018, Leather - Chemical determination of chromium (VI) content in leather - Thermal pre-ageing of leather and determination of hexavalent chromium, MOD) ISSUED ON: DECEMBER 30, 2022 IMPLEMENTED ON: JULY 1, 2023 Issued by: State Administration for Market Regulation; Standardization Administration of PRC.
Table of Contents
Foreword ... 3 1 Scope ... 6 2 Normative references ... 6 3 Terms and definitions ... 6 4 Principles ... 6 5 Instruments and equipment ... 7 6 Sampling and sample preparation ... 7 7 Test procedures ... 7 8 Test report ... 8 Appendix A (Informative) Structural changes of this document compared with ISO 10195:2018 ... 10 Appendix B (Informative) Formation of hexavalent chromium under natural ageing conditions ... 11 Appendix C (Informative) Accuracy ... 12 References ... 14 Leather - Chemical tests - Thermal ageing of leather and determination of hexavalent chromium1 Scope
This document describes a method for the determination of the hexavalent chromium content of leather under thermal ageing conditions. This document is applicable to the determination of hexavalent chromium content in various types of chrome-tanned leather under thermal ageing conditions.2 Normative references
The following documents contain the provisions which, through normative reference in this document, constitute the essential provisions of this document. For the dated referenced documents, only the versions with the indicated dates are applicable to this document; for the undated referenced documents, only the latest version (including all the amendments) is applicable to this document. GB/T 22807 Leather and fur - Chemical tests - Determination of chromium (VI) content: Colorimetric method (GB/T 22807-2019, ISO 17075-1:2017, MOD) GB/T 38402 Leather and fur - Chemical tests - Determination of chromium (VI) content: Chromatographic method (GB/T 38402-2019, ISO 17075-2:2017, MOD) GB/T 39364 Leather - Chemical, physical, mechanical and fastness tests - Sampling location (GB/T 39364-2020, ISO 2418:2017, MOD) QB/T 2716 Leather - Preparation of chemical test samples (QB/T 2716-2018, ISO 4044:2008, MOD)3 Terms and definitions
There are no terms and definitions that need to be defined in this document.4 Principles
The leather sample is heated in an oven for a specified time, and then the hexavalent chromium content in the sample is measured by spectrophotometry or chromatography after cooling.5 Instruments and equipment
5.1 Static oven: The temperature required for the test can be controlled, and the temperature control accuracy is ±2 °C. The oven shall not have a blower or other air circulation system, nor shall it have openings for air exchange, and the interior of the oven shall be made of inert materials. A natural convection oven should be used. 5.2 Erlenmeyer flask with a stopper: 250 mL; it is used to contain the sample and can be kept at 80 °C for 24 h and cooled at room temperature. The Erlenmeyer flask meets the requirements for determining the content of hexavalent chromium according to the provisions of GB/T 22807 or GB/T 38402. 5.3 Temperature and humidity measuring instrument: The allowable error of the temperature indication is not more than ±1 °C, and the indication error of the relative humidity is not more than ±5%. 5.4 Analytical balance: The accuracy is 0.1 mg.6 Sampling and sample preparation
6.1 Sampling The sampling shall be carried out according to the provisions of GB/T 39364. If it is not possible to take samples at standard locations (such as leather on shoes and clothing), take samples at any location within the usable area. The samples shall be representative and shall be noted in the test report. 6.2 Sample preparation Sample preparation shall be carried out according to the provisions of QB/T 2716, and the sample is cut into 3 mm~5 mm sheets.7 Test procedures
7.1 Preheat the oven (5.1) to the specified temperature, see Table 1.Appendix C
(Informative) Accuracy The test results among multiple laboratories in June 2016 are as follows: This interlaboratory trial was to compare the effect of two ageing methods (thermal and light) on the hexavalent chromium content in leather. A total of 7 laboratories and 5 chrome-tanned leather samples were involved in the study. a) Sample A: bovine crust leather without finishing; the technology for reducing the hexavalent chromium content was used in its production process, including the use of reducing agents. b) Sample B: bovine crust leather without finishing; the technology for reducing the hexavalent chromium content was used in its production process, but no reducing agents were used. c) Sample C: black finished leather. d) Sample D: bovine crust leather, no technology to reduce the hexavalent chromium content was used in its production process, but the vegetable tanning agent was used. e) Sample E: bovine crust leather, no technology to reduce the hexavalent chromium content was used in its production process. Samples were distributed to different laboratories during the same week in 2016 (Week 29). The test of hexavalent chromium content was carried out according to ISO 17075-2 (chromatographic method). The test results of thermal ageing treatment are shown in Table C.1. ......Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al.
