Fixing agents are additives used to improve the dyeing fastness of dyes on fabrics. As a finishing agent, it can combine with the ionic water-soluble groups of dyes to form insoluble colored substances, improving the washing and sweating fastness of colors, reducing the hydrophilicity of dyes, effectively improving the fixation rate, water washing resistance, friction fastness, and dye utilization rate of dyes, and sometimes improving their light fastness.

The pulp fibers are always yellow to grayish white, which is due to the absorption of purple and blue light with wavelengths of 0.4-0.5 um by the lignin contained in the pulp fibers. The higher the lignin content in the pulp, the darker the color. Grinded wood pulp contains a large amount of lignin, which is light yellow in color. Fluorescent whitening agents can be added to improve whiteness. Today, the editor will take you to understand the whitening principle of fluorescent whitening agents and the factors that affect their whitening effect.

Dyes are not unfamiliar to us, and they are indispensable in daily life. Simply put, dyes can be divided into two types: chemical dyes and environmentally friendly dyes. Chemical dyes are dyes made from compounds through a series of chemical reactions or directly using colored chemical substances. Environmental friendly dyes are different, as they are obtained from plants, animals, or mineral resources and have hardly undergone chemical processing.

“乌黑”与“雪白”恰恰相反,在颜色的明度上,“雪白”要求浅到极致,织物的反光率要尽可能大; 而“乌黑”则要求深到极致,织物的反光率要尽可能小。

拔色，又称剥色，一般是利用化学反应，破坏纤维上的染料与纤维的结合、破坏纤维上的染料结构，使染料剥离纤维和不能发色。

主要是涤纶纤维染色是高温高压，虽然分散染料分子小但是也不能保证染色时候染料分子全部进入纤维内部，有的分散染料会附着在纤维表面，不除去这些浮色会造成牢度过差，这时候还原清洗用强还原剂将没有进入纤维内部的染料分子破坏，可以提高牢度，改善色光。