Similarities and differences between organic pigments and dyes and inorganic pigments

 As we all know, colorants are basically divided into organic pigments, dyes and inorganic pigments. Organic pigments have developed rapidly recently. What are the similarities and differences with the other two kinds of coloring agents?

Similarities and differences between organic pigment and dyestuff

Organic pigments and dyes are all colored organic compounds. From the chemical structure of organic pigments and dyes, they are very similar. Even some organic compounds can be used both as dyes and as organic pigments. But organic pigments and dyes are two different concepts. The difference between them is mainly the same. The application performance is different.

The traditional use of dyes is to dye textiles, and the traditional use of the pigment is to coloring non textiles (such as ink, paint, paint, plastic, rubber, etc.). This is because the dyes have affinity (or direct) to textiles, which can be adsorbed and fixed by fiber molecules, and the pigments have no affinity for all the colored objects, and they are combined with the coloring object, mainly by other film forming substances, such as resin, adhesive and so on. In the process of use, dyestuffs are usually dissolved in the use of medium, even if they are disperse dyes or reducing dyes, they also undergo a process of dyeing the fibers from the state of crystal first to the state of water and then on the fiber. Therefore, the color of the dye itself does not represent its color on the fabric. In the course of using the pigment, it does not dissolve in the medium, so it always exists in the original crystal state. Therefore, the color of the pigment itself represents its color in the substrate. Because of this, the crystal state of the pigment is very important to the pigment, and 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.

Pigment and dye are different concepts, but they can be used in specific situations. For example, some anthraquinone vat dyes are insoluble dyes, but they can also be used as pigments after pigmentation. These dyes are known as pigment dyes or dyestuff pigments.

Similarities and differences between organic pigments and inorganic pigments

Inorganic pigments are oxides of nonferrous metals, or some metal insoluble metal salts, inorganic pigments are divided into natural inorganic pigments and artificial inorganic pigments, and natural inorganic pigments are mineral pigments.

Organic pigments are colored organic compounds. They are also divided into two categories: natural and synthetic. Nowadays, organic pigments are commonly used. Organic pigments have many varieties, and their colors are quite complete, and their performances are better than those of inorganic pigments.

Inorganic pigments are mainly carbon black and iron oxide, titanium, barium, zinc, cadmium, lead and other metal oxides or salts.

Organic pigments can be divided into single azo, double azo, color lake, phthalocyanine or fused ring pigments.

Inorganic pigment is resistant to sun, heat-resistant, weatherability, good solvent resistance and strong covering power, but the chromatogram is not complete, the coloring force is low, the color brightness is poor, and some metal salt and oxide are toxic.

Organic pigments are diverse in structure, complete chromatography, bright and pure color, strong coloring force, but some products are light resistant, weather resistant, poor solvent resistance, high grade organic pigments also have good light resistance, weather resistance, solvent resistance, but expensive.