Foreword
This document is drafted in accordance with the provisions of GB/T 1.1-2020 "Guidelines for standardization work Part 1: Structure and drafting rules of standardization documents".
Please note that some of the contents of this document may involve patents. The issuer of this document does not assume responsibility for identifying patents. This document is presented by the China Textile Industry Federation.
This document is categorized by the Sub-Technical Committee on Basic Standards of the National Textile Standardization Technical Committee (SAC/TC 209/SC1).
1 Scope
This document specifies the use of X-ray fluorescence spectrometry (XRF) analysis to determine the total lead in textiles and their accessories, the total cadmium content of the method. This document applies to all types of textile products and their accessories for screening tests.
This document does not apply to the structure of the fabric and glass accessories are not tight.
2 Normative reference documents
The following documents constitute the essential provisions of this document through the normative references in the text. Among them, note the date of the reference document, only the date of the corresponding version applies to this document; do not note the date of the reference document, its latest version (including all the change orders) applies to this document.
GB/T 30157 Determination of total lead and total cadmium content of textiles
3 terms and definitions
The following terms and definitions are applicable to this document.
3.1
Accessoriesaccessories
Textile products play a connecting, decorative, marking or other role in the parts, for example, buttons, zippers and decorative pieces.
[Source: GB/T 31702-2015, 3.1]
4 Principle
Textile products and their accessories by X-ray excitation, the emission of characteristic X-ray fluorescence spectrum, according to its characteristic spectral energy or wavelength for qualitative analysis. The X-ray fluorescence intensity of lead or cadmium has a certain linear relationship with its content, and the working curve of the standard substance can be compared for quantitative analysis.
5 Reagents and materials
5.1 Lead standard substances made of metal
There are at least 5 series of standard substances of the same material and the lead content is in the range of 0 mg/kg~1,000 mg/kg.
5.2 Cadmium standard substances made of metal
There are at least 5 series of cadmium standard substances of the same material and the cadmium content is in the range of 0 mg/kg~1,000 mg/kg.
6 Instruments and equipment
6.1 X-ray fluorescence spectrometer: the peak of manganese element at the energy position of 5.89 keV, with a resolution of at least 170 eV.
6.2 Grinding machine.
6.3 Press: The maximum pressure is not less than 20 MPa.
7 Preparation of specimens
7.1 Uncoated textiles
The structure of the tight specimens can be stacked in multiple layers, to ensure that there is no gap between the layers after the test; for the structure is not tight specimens are recommended to use GB / T30157 for testing.
Note: If the naked eye can see the specimen fabric gaps are considered to be not tight structure, such as grid, lace, etc. q degree of, is considered to be tight structure.
7.2 coated textiles
Specimen preparation according to 7.1.
7.3 uncoated (plated) accessories
From the sample to be tested to select a representative, no obvious gaps, shape area to meet the requirements of the instrument to test the area. For small size or irregular shape of the specimen, need to do the following treatment before testing:
a) For non-metallic specimens, the same specimen can be crushed with a grinder (6.2) and then put into the specimen cup for testing;
b) for metal specimens, the same type of specimen placed on the press (6.3), slowly ramp up to 20 MPa, stay 5s, decompression removed, the test
Specimen surface should be smooth, no cracks. If the specimen is not easy to form, according to the above steps to re-compression, until the requirements are met, and then used for testing.
7.4 Coating (plating) accessories
The coating or plating should be separated from the substrate by physical means, the coating or plating and the substrate respectively according to 7.3 method of specimen preparation, if you can not split, or split the amount of specimens can not be used for testing, it is recommended that the test GB / T 30157.
8 Test procedure
8.1 The establishment of the standard curve
According to the material of the specimen, choose the standard substance matching the material and draw the standard curve, see Appendix A.
9 Calculation of results
9.1 Uncoated textiles
10 Quantitative limits
The limit of quantification of lead and cadmium is 35 mg/kg.
11 Result determination method
12Test report
Foreword
1 Scope
2 Normative reference documents
3 terms and definitions
4 Principle
5 Reagents and materials
6 Instruments and equipment
7 Preparation of specimens
8 Test procedure
9 Calculation of results
10 Quantitative limits
11 Result determination method
12Test report
