Varieties of inorganic pigments in use

Inorganic pigments include a variety of metal oxides, chromium salts, carbonates, sulfates and sulfides. For example, aluminum, copper, carbon black, zinc white and titanium white are all belong to inorganic pigments.

Main varieties of black pigments are carbon black. Main quality index of carbon black pigment is black and hue. Classification of carbon black by processing methods is variety. Carbon black not only has the coloring properties, but also has excellent weatherability and resistance to thermal oxidation.

Red paint of inorganic pigments mainly is iron oxide red. Iron oxide has a variety of colors, from yellow to red, brown and black. Iron oxide red is the most common iron oxide pigments. It has very good hiding power and tinting strength, chemical resistance and color retention, etc. Because of significant good rust resistance, iron oxide red is used for the production of floor paints and marine paints.

Currently available for auto paint inorganic pigments include titanium dioxide, carbon black, iron oxide, bismuth vanadate yellow, mixed metal oxide pigments as well as flash aluminum Flake pigment and mica pearl powder. After coating and other surface treatments, chromium yellow (PY34) and molybdateorange (PR104) are suitable for automotive coatings in terms of its weather resistance and light resistance performance, but because of toxicity, they are no longer used in automotive coatings. Meanwhile, cadmium red is also disabled on the same grounds.

Bismuth vanadate yellow is a commercialization of an inorganic yellow pigments (PY184) in the 1980s. Its chemical composition is BiVO4/nBi2MoO4, close to lemon yellow hue. It is main features are very low toxicity, bright and clean of color, good heat resistance, weather resistance, light resistance, resistance to chemicals and solvents. Its very good covering power is similar to titanium dioxide with high tinting strength, it is the ideal nontoxic substitute of chrome yellow pigment. But its disadvantages are high density and precipitation.

Mixed metal oxide pigment is a kind of inorganic pigments with an excellent chemical stability. In the crystal structure of stable metal oxide, nonferrous metal ions can show its color. Different oxides compositions can have different colors, such as titanium-nickel yellow (PY53,NiO • Sb2O3 • 20TiO2) antimony, chromium titanium Brown (PBr24,Cr2O3 • Sb2O3 • 31TiO2), cobalt blue (PB28,CoO • Al2O3) and CU-CR-black (PBk28,CuO • Cr2O3), etc. Such pigment is characterized by a very good resistance to high temperature, acid, alkali, lightfastness and weatherability, drawback is the low tinting strength, certain varieties of dispersion is not good enough. They are mainly used for ceramics and enamel colouring, coating is mainly used for high temperature resistance and coil coatings. It is available in light metallic base coat in automotive finishes. Read more!

Use trend of inorganic pigments

Inorganic pigments are pigments based on natural minerals or made by inorganic compounds. Generally, they are low purity, darker color, but at a low price. They are widely used in paints, plastics, synthetic fibers, rubber, construction materials, stationery, paint, ink, paper, glass, enamel, ceramics and other industrial sectors.

In the early 80s, inorganic pigments production capacity is 3.6Mt in the world, including: titanium dioxide is 74%, iron oxide pigments is 14.6%, chrome is 5%, anticorrosive pigment is 4.6%, chrome Green is 1%, cadmium pigments is 0.2%, etc. The annual production capacity of novel compound dye has risen to 10Kt. China inorganic pigment manufacturers are more than hundred, total output is above 200Kt.

Pigments are divided into organic pigments and inorganic pigments. Organic pigments made from pigments extracted from plants, it contains no harmful elements, which belongs to the green pigment. Inorganic pigment extract pigments from minerals, such as selenium, cadmium, chromium, etc.

Basic optical properties and dyes properties of inorganic pigments mainly determined by the following three aspects:

a. difference in refractive index between pigments and dispersion medium;
b. the light is absorbed by the solid (including impurities in solids);
c. particle size and particle size distribution. The particle size and particle size distribution can be improved by surface treatment.

In paint production process, however fine pigment powder, there will always contain some aggregation and flocculation of particles. Due to compression or moisture, pigments will be further cemented flocculation of particles in the course of transport and storage. If an appropriate surfactant treatment, these flocculation of particles can easily be dispersed in use.

Tendency of research and development of new inorganic pigments in recent years are:

1. develop complex pigments, such as light blue (CoO • Cr2O3• Al2O3), titanium-nickel yellow (TiO2 • NiO• Sb2O3) and so on. Add oxides of chromium, cobalt, iron and zinc to nickel titanium, antimony salts can make yellow, green, blue, brown, etc pigments that are high temperature resistance, durability, chemical resistance and low toxicity to nontoxic. They are bright and have excellent performance, can be used for building materials, paint, plastics coloring and paint preparation.

2. develop surface treatment technology of pigment particle, form a layer of color film as inorganic compounds or organic pigment on the particle surface, it can change the surface properties of pigment particle, improve light resistance, heat resistance, wetting properties, expand applications and improve value.
3. make manufacture pigments to save a lot of abrasive machining costs. If you want to know more, click here!

Inorganic pigments in the industry

Almost all inorganic pigments are compounds and they are usually complex mixtures, , in which metal is a part of the molecule. As the global economy recovers, building materials, paint, plastic, ink and other industries have seen rapid growth, the demand of inorganic pigments is increasing rapidly. Along with the rapid development of coatings industry, as one of its main raw materials of inorganic pigments have enjoyed great development, such as titanium dioxide and iron oxide take a large percentage.

Research report about China coatings market and investment strategy in recent years, the pigments manufacturers‘ orders increased, price fluctuations is frequent, local supply is tight. China as a producer of inorganic pigments, the total annual production of titanium dioxide, iron oxides, chromium pigment lead the highest in the world. It is understood green inorganic pigments showed a growth trend of the volume and price in 2012, as well as in 2013. For this reason, inorganic pigments enterprise should advance the core competitiveness bases on scientific and technological innovation for the brand to make new contributions to environmental change.

Inorganic pigments are non-ferrous oxide or insoluble metal salts of some metals. Inorganic pigments are divided into natural inorganic and inorganic pigments, natural inorganic pigments are mineral pigments. Humans have a long history in using inorganic pigments. Smoke black, chalk, clay, natural iron oxide has been used as pigments since prehistoric times. Around 200 BC, China refined vermilion (HgS) as pigments. 1704 Germany Diesbach invented manufacturing method of color pigment Prussian blue (a blue pigment, main ingredient Fe4 "Fe (CN) 6" 3 • xH2O). 1809 France L.-N. made chrome Vauclin, 1831 France I.B. JI May built a plant near Lyon to manufacture Ultramarine, 1874 the United Kingdom Austria's zinc company-owned Widnes factories manufactured zinc barium White. Titanium pigments (including TiO225%) in 1916 and pure titanium dioxide (Titania) in 1923 put into production, which lead the pigment production levels to advance one step further.

Tendency of research and development of new inorganic pigments in recent years are:
a. Develop complex pigments, such as light blue (CoO • Cr2O3• Al2O3), titanium-nickel yellow (TiO2 • NiO• Sb2O3) and so on. Add oxides of chromium, cobalt, iron and zinc to the titanate of nickel and antimony can make low toxicity to nontoxic pigments, and the pigments are yellow, green, blue, Brown with high temperature resistance, durability, bright and excellent performance. It can be used for building materials, paint, plastics coloring, etc.
b. Develop surface treatment technology of pigment particle, form a layer of color film on the inorganic compounds or organic pigment particle surface. It can change the pigment particle surface properties, improve light resistance, heat resistance, wetting properties and expand applications and improve value.
c. Manufacture machining pigments, users can use directly and save a lot of abrasive costs. Click here to get more!