Leather Matrix Standard Samples Were Released For The First Time To Fill Gaps At Home And Abroad.

< p > < strong > matrix > a href= "//www.sjfzxm.com/news/index_c.asp" > standard sample < /a > deletion affects detection accuracy < /strong > /p >

< p > according to Qi Xiaoxia, Secretary General of the national standard sample Technical Committee leather and footwear professional working group, the leather and footwear industry Research Institute of China has carried out research and feasibility analysis of leather matrix standard samples in 2009 and carried out research work in the industry.

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< p > according to the introduction, with the increasingly stringent requirements for leather safety and hygiene performance at home and abroad, leather chemical testing has received unprecedented attention and rapid development. However, the lack of matrix standard samples seriously affects the accuracy of the test results.

Many testing organizations use pure standard samples and solution standard samples in daily inspection. They ignore the interference of the matrix effect of the a href= "//www.sjfzxm.com/news/index_c.asp" > grease > /a > protein, chemical aid and fillers in the leather matrix, and are prone to "false positive" and quantitative uncertainty, which can not guarantee the accuracy of the test results.

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< < p > in CNAS-CL10:2012 < < a href= > //www.sjfzxm.com/news/index_c.asp > > /a > and the application specification of the accreditation criteria for the calibration laboratory in the field of chemical detection, it is required that "certified standard samples and laboratory controlled samples should be consistent with the sample matrix as far as possible". However, leather inspection bodies have not been provided with the corresponding matrix standard samples for a long time, which seriously affect the accuracy of the test results and the traceability of the data.

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< p > < strong > five years research and exploration to fill gaps at home and abroad < /strong > < /p >

< p > it is precisely to comply with market demand. In 2009, China leather and footwear industry Research Institute began to carry out research work on leather matrix standard samples. In May 18, 2011, the national standard sample Technical Committee approved the establishment of the leather and shoemaking professional working group and assumed the Secretariat's work, responsible for the technical convergence of leather and footwear standard samples. In December 2011, the National Standardization Management Committee approved the project to develop heavy metal and standard samples of two methyl fumarate in leather.

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< p > it is understood that the development of standard samples is a new and important field in leather and shoemaking industry in China. It has received wide attention and strong support from the national standard sample Committee and leather industry, but also encountered many technical problems in the development process.

Qi Xiaoxia said, how to add harmful substances evenly and steadily to leather matrix is also a big problem for researchers.

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< p > after many summing up experiments, "later we adopted the technology of simulating leather industry, adding hazardous substances through physical and chemical methods to ensure that the physical and chemical properties of the standard samples are consistent with the actual samples."

Qi Xiaoxia told China Leather net reporter that leather is a solid material, and because of the different nature of the combination of different cortical structures and compounds, the requirement of uniformity can not be achieved. The important index of standard samples is the uniformity of the substances to be measured in the matrix. "We have been troubled by this problem for a long time, but we have overcome this difficulty through ultrafine grinding and screening technology."

She said that the technology ensures that the particle size of the sample is between 60 mesh and 100 mesh, thus achieving uniform distribution of the tested substance in leather.

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< p > after nearly five years of research and exploration, GSB 16-3086-2013 "standard samples of methyl esters of fumaric acid in leather" and GSB 16-3087-2013 "standard samples of lead, cadmium, nickel, chromium, cobalt, copper, antimony, arsenic and mercury in leather" two leather matrix standard samples were officially approved by the state Administration of quality supervision, inspection and quarantine and the National Standardization Technical Committee in December 17, 2013. This is also the first standard leather matrix standard issued by our country. It indicates that China's leather industry has made substantial breakthroughs in the development of standard samples, and has filled the blank of standard leather samples at home and abroad.

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< p > < strong > provide inspection and technical support for leather manufacturing enterprises < /strong > < /p >

< p > according to Qi Xiaoxia, the leather matrix standard sample approved by this approval is popularly referred to as leather material, which contains a certain amount of heavy metal or two methyl fumarate sample, and the chemical substance is evenly distributed and stable in leather.

The standard sample can be used for qualitative and quantitative analysis of hazardous substances in leather, and can also be used as quality control samples for laboratory quality control activities such as proficiency testing, comparison test, capability evaluation and method validation.

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< p > she said that the standard sample of heavy metal and fumaric acid two methyl ester matrix in the leather is a chemical standard sample. At present, the standard sample system of leather and footwear in China is divided into three categories. In addition to the above-mentioned chemical standard samples, physical samples are also included, such as the standard sample of the longitudinal stiffness of footwear, the standard sample for wear resistance of shoes, etc., and standard samples (such as leather shoes, rubber shoes, standard samples of appearance defects of cloth shoes, etc.).

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< p > the chemical standard samples released this time will comprehensively improve the accuracy of leather chemical testing technology in China, ensure the effective implementation of relevant written standards, improve the safety of leather and its products, protect the health of consumers, and improve the quality of life of consumers.

At the same time, it will also promote the quality control of leather inspection laboratory and the traceability of test data, and provide samples with accuracy and accuracy for proficiency testing, inter laboratory comparison, self calibration and other activities.

In addition, it will also help our organization to participate in international comparison and mutual recognition of international testing and verification results, and provide more reliable technical support for China's leather production enterprises to clear up technical barriers to cope with green barriers.

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< p > for this reason, Qi Xiaoxia said that according to China's conformity assessment National Accreditation Committee CNAS-CL10:2012 "testing and calibration laboratory accreditation criteria in the field of chemical testing application instructions", the two standards issued, since the date of promulgation, all carry out leather chemical related testing project CNAS accreditation inspection institutions are required to use.

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