Zirconium silicates
Zirconium silicates (also zirconium silicates ) are synthetic inorganic pigments of varying composition and are used as ceramic pigments . They are produced in the basic colors blue, yellow and red. All possible colors can be covered by mixing. In addition, zircon is a natural representative of this class.
Zirconium silicate pigments
- Zircon Vanadium Blue : This pigment was first produced in 1948 and a US patent pending. It covers the colors blue to blue-green. The basic substances for production are zirconium dioxide , silicon dioxide , ammonium metavanadate and sodium fluoride , which are annealed at 850 to 1000 ° C.
- Zirconium praseodymium yellow is made from zirconium dioxide, silicon dioxide, praseodymium oxide (Pr 6 O 11 ) and sodium fluoride by annealing at 1250 ° C. This yellow pigment was first developed in Japan in the 1950s.
- Zircon-Iron-Pink was first made in 1960. The starting materials are zirconium dioxide, silicon dioxide, iron (II) sulfate and sodium fluoride, which are annealed at 880 to 1100 ° C. It appears in the colors pink to red.
- Zirconium silicate inclusion pigments are based on the fact that the colorless zirconium silicate ZrSiO 4 acts as a shell former and certain pigment formers as inclusions cause the desired color. The red pigment of this class developed by Degussa is the cadmium sulfoselenide-zirconium silicate inclusion pigment (Cd (S, Se) -ZrSiO 4 ). The cadmium sulfoselenide is formed during the synthesis from cadmium carbonate , sodium sulfite and selenium by adding a mineralizer.
literature
- Peter Kleinschmit: A chapter in applied solid ‐ state chemistry: zirconium silicate stains . In: Chemistry in Our Time . tape 20 , no. 6 , 1986, pp. 182–190 , doi : 10.1002 / ciuz.19860200604 .