One-step color-development screening method for banned azo-dye in dyeing 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...

Examples

Embodiment 1-29

[0026] Embodiment 1-29: Test results of 29 actual fabric samples

[0027] First, the developer formula: dissolve 1g of N,N-dimethyl-4-aminobenzaldehyde in 75mL of ethanol, add 25mL of hydrochloric acid, mix well before use.

[0028] Secondly, the collected instruments were detected to contain 2-naphthylamine, p-chloroaniline, o-toluidine, 3,3'-dimethoxybenzidine, 5-nitro-o-toluidine, 2,4-diamino 8 kinds of banned aromatic amines such as toluene, 2,4-diaminoanisole and 4-aminoazobenzene, the content ranges from 29 cloth samples of 5 mg / kg-557 mg / kg, and is measured according to the steps of the present invention , are all colored, the detection rate of this method is 100%, and there is no false negative. Specific steps are as follows:

[0029] (1) Reduction of samples: Weigh 2.0 g of chopped representative samples into a reaction bottle, add 16 mL of citrate buffer solution (0.06 mol / L, pH=6) and 3.0 mL of sodium dithionite solution (200 mg / L mL, ready-to-use), seal the reac...

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...

Examples

Embodiment 1-29

[0026] Embodiment 1-29: Test results of 29 actual fabric samples

[0027] First, the developer formula: dissolve 1g of N,N-dimethyl-4-aminobenzaldehyde in 75mL of ethanol, add 25mL of hydrochloric acid, mix well before use.

[0028] Secondly, the collected instruments were detected to contain 2-naphthylamine, p-chloroaniline, o-toluidine, 3,3'-dimethoxybenzidine, 5-nitro-o-toluidine, 2,4-diamino 8 kinds of banned aromatic amines such as toluene, 2,4-diaminoanisole and 4-aminoazobenzene, the content ranges from 29 cloth samples of 5 mg / kg-557 mg / kg, and is measured according to the steps of the present invention , are all colored, the detection rate of this method is 100%, and there is no false negative. Specific steps are as follows:

[0029] (1) Reduction of samples: Weigh 2.0 g of chopped representative samples into a reaction bottle, add 16 mL of citrate buffer solution (0.06 mol / L, pH=6) and 3.0 mL of sodium dithionite solution (200 mg / L mL, ready-to-use), seal the reac...

Images