Generally speaking, textile testing is to test the comprehensive performance and overall quality of textile fibers, yarns, fabrics and even garments. The conventional testing items are: fiber content, pH value, formaldehyde content, decomposable carcinogenic aromatic amine dyes, color fastness Spend.
1. Fiber content
As the name implies, it is to detect the fiber composition and content of textile raw materials. The fiber content of the raw materials will directly affect the quality of the finished product. Therefore, the fiber content is the most basic and important item in textile testing.
2. PH value
In the textile printing and dyeing process, the dyes are more or less not fully washed or neutralized, which causes the fabric to be too acid and alkali, which exceeds the pH value of human skin. It is easy to cause skin itching, allergies, inflammation and other diseases, which affect human health. In order to improve the safety performance of textiles, the pH value is also an important indicator. The national mandatory standard GB 18401-2010 "National Basic Safety Technical Code for Textiles" has clear provisions:
3. Formaldehyde content
In fabric production, in order to achieve the effects of anti-wrinkle and shrink-proof, or to maintain the durability of printing and dyeing, or to improve the feel, formaldehyde must be added to the auxiliary agent. Textiles containing formaldehyde will gradually release free formaldehyde when people wear and use it, which will endanger the health of the wearing people. Therefore, the content of formaldehyde is also one of the important indicators for textile testing.
4. Decomposable carcinogenic aromatic amine dyes
Refers to the dyes synthesized from carcinogenic aromatic amines, that is, people often say "banned azo dyes". For textile safety indicators, decomposable aromatic amines are far more toxic and carcinogenic than formaldehyde. Because formaldehyde has a pungent odor, it is easy to distinguish, and it is easily soluble in water. After consumers buy textiles, they usually wash it with water to remove most of the formaldehyde; but after decomposable aromatic amine dyes are made into clothes, they are not only insoluble in water, Moreover, it is colorless and tasteless, and cannot be distinguished from the appearance of textiles. It can only be found through technical inspection and cannot be eliminated. After this dye comes into contact with human skin, it can cause a variety of malignant diseases and absorb cancer. Therefore, the importance of detecting decomposable carcinogenic aromatic amine dyes can be imagined.
5. Color fastness
In the use or post-processing of dyed fabrics, the dye is affected by various external factors, whether it can maintain the original color and luster. The fastness grade is evaluated according to the discoloration of the sample and the staining of the undyed lining fabric.