17 августа, 2015 
Pokraskin Hartmut Endriss
Bismuth vanadate pigments are a relatively new pigment class that has gained steadily in importance over the last two decades. The pigments exhibit brilliant greenish-yellow to reddish-yellow shades, with compositions ranging from BiVO4 (CAS No. 14059-33-7, EINECS No. 237-898-0) to the mixed pigment 4BiVO4 x 3Bi2MoO6. They appear in the Colour Index as CI Pigment Yellow 184 without any statement as to chemical composition. To improve the properties, including the tendency to photochromism, bismuth vanadate pigments in paints contain several percent of organic stabilizers.
Color changes may occur when these pigments are used to color plastics, because of reduction of the vanadate ion in the polymer melt. Thermostable types suitable for coloring plastics are therefore protected by a dense, glass-like, multilayer coating composed of the oxides of aluminum, boron, silicon and zinc. Bismuth vanadate pigments are lead — and chromate-free inorganic yellow pigments used in the coatings industry to manufacture brilliant yellow, orange, red and green shades with good gloss and hiding power. As thermostable types become more available, the plastics industry is also increasingly turning to these pigments. Bismuth vanadate pigments have benefited from the decline in use of lead chromate and cadmium pigments, especially in the coatings and plastics industries.
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