Similarities and Differences Between Organic Pigments, Dyes, and Inorganic Pigments

Similarities and differences between organic pigments and dyes

Both organic pigments and dyes are colored organic compounds. From the chemical structure of organic pigments and dyes, the two are very similar, and even some organic compounds can be used as both dyes and organic pigments, but organic pigments and dyes do Are two different concepts, the difference between them is mainly the application performance is different.

The traditional use of dyes is to dye textiles, while the traditional use of pigments is to color non-textiles such as inks, paints, coatings, plastics, rubber, etc. This is because dyes have affinity (or directness) to textiles and can be adsorbed and fixed by fiber molecules; while pigments have no affinity for all coloring objects, and mainly rely on resins, adhesives and other film-forming substances to combine with the coloring objects together. In the process of use, the dyes are generally dissolved in the use medium first. Even disperse dyes or vat dyes have undergone a process of first dissolving in water from a crystal state to a molecular state and then dyeing on the fiber during dyeing. Therefore, the color of the dye itself does not represent its color on the fabric. During the use process, the pigment always exists in the original crystal state because it is insoluble in the use medium. 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, 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 used in common in certain situations. For example, some anthraquinone vat dyes, which are insoluble dyes, can also be used as pigments after pigmentation. Such dyes are called pigment dyes, or dye pigments.


Similarities and differences between organic pigments and inorganic pigments

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

Organic pigments are colored organic compounds that are also divided into two categories: natural and synthetic. Nowadays, synthetic organic pigments are commonly used. There are many varieties of organic pigments, and the colors are relatively complete, and their performance is better than that of inorganic pigments.

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

Organic pigments can be divided into several categories such as monoazo, disazo, lake, phthalocyanine or fused ring pigments.

Inorganic pigments are light-fast, heat-resistant, weather-resistant, solvent-resistant, and have strong covering power, but the color spectrum is not very complete, the tinting strength is low, the color brightness is poor, and some metal salts and oxides are highly toxic.

Organic pigments have diverse structures, complete chromatograms, bright and pure colors, and strong tinting strength, but some products have poor light resistance, weather resistance, and solvent resistance. Organic pigments also have good light resistance, weather resistance, and solvent resistance, but they are expensive.