A one-step chromogenic screening method for prohibited azo dyes in dyed textiles

Abstract

The invention discloses a one-step color-development screening method for banned azo-dye in dyeing textiles. The one-step color-development screening method comprises the following steps: (1) reducing a sample; (2) color-development, to be specific, at the same position of filter paper, dripping a drop of a color-developing agent, and then dripping 1-2 drops of tert-butyl methyl ether extracting solution for color development, wherein the color-developing agent is an ethanol solution comprising paradimethylaminobenzaldehyde with the mass-volume ratio of 0.1-10% and hydrochloric acid with the volume ratio of 10-25%; (3) screening and determination, to be specific, judging results according to the fact that whether obvious color change occurs or not after dripping the sample solution on the color-developing agent, wherein if no obvious color change occurs after color development of the sample solution, the sample does not contain a substance to be detected or the concentration of the substance to be detected is lower than the detection limitation, and the result is negative; if obvious color change occurs after color development of the sample solution, the sample is likely to contain the banned azo-dye, the result is positive, and further confirmation is required to be carried out by a chromatographic apparatus. The one-step color-development screening method is simple and fast, the sample can be directly subjected to color-development to be determined after being reduced, and the whole color development process can be completed within 1 min.

Description

technical field [0001] The invention relates to a one-step color screening method for prohibited azo dyes in dyed textiles, belonging to the technical field of analytical chemistry. Background technique [0002] From the world's first regulations on consumer product safety: the "Food and Consumer Goods Act" promulgated by the German Federal Government on April 10, 1992, to the 97 / 548 / EC Directive passed by the European Union in 1997, and my country's national Compulsory standard GB 18401-2003 "National Basic Safety Technical Specifications for Textiles", the detection of banned azo dyes suspected of carcinogenic aromatic amines has always been the most important and basic safety technical requirement in the international textile and clothing trade, and it is also the most important requirement for consumers all over the world. hot spot of attention. [0003] So far, a series of mature detection methods have been introduced for the testing of banned azo dyes in textiles and cl...

AI Technical Summary

Problems solved by technology

However, due to the complex pretreatment process, the need for precision instruments in the detection process, the long inspection cycle, high inspection costs, harsh detection conditions, strong dependence on large-scale chromatographic instruments, and high requirements for the technical level of practitioners, etc., make The application of this type of method is still limited to some qualified laboratories

[0006] (2) The amount of samples tested is large

[0007] my country is a big exporter of textiles and clothing. Judging from the detection of banned azo dyes in textiles in recent years, a large number of detection requirements pose challenges to the efficient and fast detection technology.

[0008] (3) The detection rate of positive samples is low

In recent years, the detection rate of banned azo dyes in textiles is less than 1% in actual detection

The whole pretreatment method is not simple enough, and the color development method is not fast enough and takes a long time

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