Home> Solution

What are organic pigments?

Date:2022-03-15

  Organic pigments are insoluble organic substances that are usually added to the substrate in a highly dispersed state to color the substrate. It is fundamentally different from dyes in that dyes are soluble in the dyeing medium used, whereas pigments are neither soluble in the medium in which they are used nor in the substrate being colored. Many pigments and dyes have the same chemical structure, and they can be converted into each other by different methods of use. For example, some vat dyes and sulfur vat dyes can be used as fiber dyes if they are reduced to leuco. ; If not reduced, it can be used as a pigment for advanced ink. Organic pigments are widely used in inks, paints, coatings, raw pulp coloring of synthetic fibers, pigment printing of fabrics, coloring of plastics, rubber, and leather, etc. Among them, the pigments of inks are used in the largest amount. The output of organic pigments accounts for about a quarter of the total output of dyes.
  Sort by structure
  (1) Azo pigments account for 59%
  (2) Phthalocyanine pigment accounts for 24%
  (3) Triarylmethane pigment accounts for 8%
  (4) Special pigments account for 6%
  (5) Polycyclic pigments account for 3%
  physical properties
  Organic pigments have bright colors and strong tinting strength; they are non-toxic, but some varieties are often inferior to inorganic pigments in light resistance, heat resistance, solvent resistance and migration resistance.
  The varieties of colors are endless and colorful, but there is a certain internal relationship between various colors. Each color can be determined by 3 parameters, namely hue, lightness and saturation. Hue is a feature that distinguishes colors from each other. It is determined by the chromatographic composition of the light source and the perception of each wavelength emitted by the surface of the object to the human eye. It can distinguish red, yellow, green, blue, purple and other characteristics. Brightness, also known as brightness, is a characteristic value that represents the change in the degree of light and dark on the surface of an object; by comparing the lightness of various colors, the color can be divided into light and dark. Saturation, also known as chroma, is a characteristic value that represents the shade of color on the surface of an object, making the color different from bright and dark. Hue, lightness, and saturation form a solid, and using these three to establish a scale, we can measure color numerically. The colors in nature are ever-changing, but the most basic are red, yellow and blue, which are called primary colors.