A pigment is a substance that can stain an object. Pigments are soluble and insoluble, with inorganic and organic differences. Inorganic pigments are generally mineral substances, humans have long known that the use of inorganic pigments, the use of colored soil and ore, in the rock painting and smear the body. Organic pigments are generally taken from plants and marine animals, such as saucer, rattan and ancient Rome.
Pigments can be divided into organic pigments and inorganic pigments. Inorganic pigments are usually metal oxides, sulfides, sulfates, chromates, molybdates, salts and carbon blacks. Pigment These pigments are insoluble in common solvents and plastics. Their thermal stability and light stability are generally better than organic pigments, but their coloring properties are worse than organic pigments. The relative density of inorganic pigments is generally large, generally 2.5 to 5.0, and the price is cheaper.
Organic pigments according to their structure can be divided into azo pigments, phthalocyanine pigments, heterocyclic pigments, lake pigments, dyes, fluorescent brighteners and fluorescent pigments. Pigment From the performance comparison, although the organic pigments in the heat resistance, weatherability and hiding power as inorganic pigments, but with a relatively small density, high color strength, bright color and chromatographic integrity and so on.
Pigment performance characteristics
Pigments usually have the following properties:
Colour. A color pigment is a pigment that selectively absorbs and scatters visible light
In the natural light conditions show yellow, red, blue, green and other colors.
Tinting force. The ability of the pigment to absorb the incident light. Can be expressed as a relative percentage of the color strength of the standard pigment sample.
Hiding power. The ability to cover the surface color of the substrate in the film-forming material. Commonly used to cover 1 square meters of paint in the area of paint contained in the number of grams.
Lightfastness. The pigment retains its original color performance under certain light. Generally use the eight system that eight best.
Weatherability. Pigment in a certain natural or artificial weather conditions, Pigment to maintain its original performance. Generally used five-level system that five best.
Volatile. Mainly refers to the water, the general provisions of not more than 1%.
Oil absorption. Refers to 100 grams of pigment to form a uniform clumps when the number of refined linseed oil to the small amount of oil as well, the oil absorption and pigment particles relative to the specific surface area and structure.
Water soluble. Pigments contain water-soluble substances, expressed as a percentage of the pigment's mass. Paint with the paint, Pigment the water-soluble substances often controlled at 1% or less.