Dyestuffs refer to organic substances that can color fibers and other materials firmly. There are many types of dyes, which can be divided into natural dyes (such as vegetable dyes, animal dyes, mineral dyes, etc.) and synthetic dyes (or artificial dyes) according to their sources. According to the molecular structure, it can be divided into azo dyes, anthraquinone dyes, phthalocyanine dyes, arylmethane dyes, nitro dyes and so on. According to the application method, it is divided into acid dyes, basic dyes, sulfur dyes, reactive dyes, disperse dyes, direct dyes, etc. Dyes have colors, but colored substances are not necessarily dyes. The dye must have a chromophore and an auxiliary chromophore. The dye in the ink should also have water-soluble groups such as sulfonic acid groups.
Dyes & Pigments List
What are Dye
Natural dyes are dyes obtained from animals, plants and minerals. According to the source, it can be divided into:
Plant dyes, dyes extracted from roots, stems, leaves and fruits of certain plants, such as indigo (blue) extracted from indigo leaves, curcumin (yellow) extracted from turmeric ), Alizarin (red) extracted from madder, etc
Animal dyes, dyes extracted from animal bodies, such as cochineal carmine, etc
Mineral dyes, dyes extracted from mineral colored inorganic substances , Such as chrome yellow, ultramarine blue, manganese brown, etc. Compared with man-made dyes, natural dyes have many shortcomings, such as incomplete chromatogram, inconvenient application, poor fastness, etc
What is Dye Made of
In natural dyes, except for a few still in use, most of them are eliminated. Synthetic dyes, also known as “artificial dyes”. It is mainly made from coal tar (or petroleum processing) fractionation products (such as benzene, naphthalene, anthracene, carbazole, etc.) through chemical processing, sometimes also called coal tar dyes. Since several of the earliest synthetic dyes were made from aniline, they are also called “aniline dyes”. Compared with natural dyes, synthetic dyes have many types, complete chromatograms, most of which are bright, washable and light fast, and can be mass-produced. Therefore, the current so-called dyes almost all refer to synthetic dyes. Its dyed products are one of the common materials for judicial identification.
Pigment is a kind of colored, black, white or fluorescent granular organic or inorganic solid. It is insoluble in water, oil or other application media, but it can be uniformly dispersed, and it is not affected by the physical and chemical effects of the media during the entire dispersion process, and still retains its unique crystal or particle structure.
According to the chemical composition, it is divided into inorganic pigments and organic pigments; according to the color, it is divided into white, red, yellow, black and other pigments; according to the source, it is divided into natural and synthetic pigments. Natural pigments are mineral (inorganic) such as Heshi, cinnabar, and laterite , Realgar, etc., as well as animal and vegetable (organic) such as Garcinia, Cochineal, etc. Synthetic pigments also have two categories: inorganic and organic; they are divided into coloring pigments, extender pigments and functional pigments according to their uses. Coloring pigments are inorganic and organic pigments that give various colors to the application medium; extender pigments are pigments that have no tinting power or hiding power. In the early days, they were mainly used to reduce product costs and improve the performance of coatings, plastics, rubber and other products. Call it filler. Now there are natural products and artificial synthetic products processed into ultra-fine particle size. Because the synthetic products have less impurity content, fine particles and can be artificially synthesized and various surface modifications as needed, they can be used to reduce the hiding power of pigments. (Such as titanium dioxide) and improve the performance of the product, so it is more appropriate to call it body (incremental) pigments. The main varieties of body pigments are mostly processed natural mineral products such as natural calcium carbonate, barite powder, and talc. , Mica powder, diatomaceous earth, quartz powder, china clay, asbestos, etc., a few are synthetic products such as precipitated calcium carbonate, precipitated barium sulfate, synthetic silica, etc.; functional pigments are pigments that give products specific functions, such as making the product change with temperature And color-changing temperature-indicating pigments, anti-fouling pigments with toxic and aquatic-killing functions, luminescent pigments that can emit light in the dark, anti-rust pigments that can prevent corrosion, pearlescent pigments with pearl luster, etc.
Use Of Pigments
Pigments are widely used in coatings, printing, rubber, plastics, paper, fiber, ceramics and other industries, which can make products have decorative, opaque, durable or special functions. With the advancement of science and technology, various high-performance pigments will be further developed.