Colour development of red perovskite pigment Y(Al,Cr)O-3 in various ceramic applications

Ceramic pigments based on the perovskite structure develop a promising red hue and furthermore present no environmental or health problems. Pigment coloring efficiency was tested in different ceramic applications, both in the body and in glazes. Final products, with variations in both max. firing temp. and soaking time, were characterized by colorimetry. The investigation focused on the factors and mechanism influencing perovskite dissoln. by calcg. phase compns. of different ceramic matrixes and observing pigment microstructure. Pigment powders were also characterized by structural anal. and spectroscopy. Pigment dissoln. was only slightly affected by the firing cycle, mostly being governed by the amt. and chem.-compn. of the liq. phase. In particular, the larger the content of chem. aggressive components such as calcium, magnesium, zinc and lead oxides, the stronger and faster the pigment dissoln.