The organic compounds of organic pigments and dyes are very similar from the chemical structures of organic pigments and dyes. Even some organic compounds can be used as dyes and can be used as organic pigments, but organic pigments and dyes are two different concepts. , The main difference is that the performance of the application is different.
The traditional use of dyes is to dye textiles, while the traditional use of pigments is to dye non-textiles. This is because dyes have affinity (or directness) to textiles and can be absorbed and fixed by fiber molecules. However, the pigment has no affinity for all colorants, and is mainly composed of film-forming substances such as resins and adhesives and colorants. In the dyeing process, the dye is usually first dissolved in the medium used. Even disperse dyes or vat dyes have to undergo a dyeing process from crystalline state to water state to molecular state and then to fiber. Therefore, the color of the dye itself does not represent its color on the fabric.
Since the pigment is insoluble in the medium, it always exists in the original crystal state. Therefore, the color of the paint itself represents the color of its substrate. Because of this, the crystal state of the pigment is very important to the pigment, while the crystal state of the dye is not so important, or the crystal state of the dye itself is not closely related to its dyeing behavior.
Although pigments and dyes are different concepts, they can be universal under certain circumstances. For example, some anthraquinone vat dyes are insoluble dyes, but they can also be used as pigments after pigmentation. Such dyes are called pigment dyes or dyes.