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Performance testing of basic dyes

2021-03-31

To judge the quality of dyes is based on their performance, the following describes the performance testing of basic dyes:

1. Performance testing of basic dyes: 1) Soaping fastness of basic dyes: the degree of fading of dyed fabrics after soaping in soap solution under specified conditions, including the original fading and white cloth staining. The soaping fastness is lower than that of alkaline bright yellow o structure and Basic bright yellow is related to the binding state of fiber. 2) Light fastness of basic dyes: Under the action of sunlight, the dye absorbs light energy, and the molecules are in an excited state and become very unstable. It is easy to produce certain reactions, which will cause the dye to decompose and fade. Generally, the light fastness is divided into two parts. Level 8.

3) Rubbing fastness of basic dyes: basic bright yellow o The dyed fabrics produced can be divided into dry rubbing and wet rubbing fastness. The former is used for white cloth rubbing fabric, and the latter is rubbed and dyed with white cloth with 100% water. For fabrics, wet rubbing fastness is generally lower than dry rubbing fastness.

2. Basic dyes cannot be used as food additives: 1) Basic dye is a kind of basic industrial dye. It is mainly used for dyeing silk, hemp, leather, paper, straw knitting, etc. This substance is carcinogenic to humans. It is hygienic according to the use of food additives. The standard stipulates that it is strictly prohibited to be used as a food additive. 2) Basic dyes have a mild irritant effect on the skin and mucous membranes, which can cause conjunctivitis, dermatitis and upper respiratory tract irritation. People are easily poisoned if touched or inhaled.

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