Bearing in mind the limitation in the color of inorganic pigments, one has to be surprised at the numbers of new compounds introduced with good pigment performance. More and more, specialized physical effects appear to dominate over variation in chemical composition. In Table 1.1, for example, we must point out that mica-based effect pigments, being still a “young” pigment class, have already become well established since their “breakthrough” introduction. Again, while bismuth vanadate yellow is in the early stages of its growth potential, cerium sulfides
are in their industrial infancy, and are attempting to carve out a niche for themselves in applications where the well-established cadmium sulfide family is no longer the pigment of choice. On the more experimental side, “nanoscale silicon,” with particle size below 5 nm, is now available as a laboratory curiosity in microgram quantities as the first in the series of “quantum effect pigments” predicted by theoretical physicists [3]. Nearer to introduction is another new family, the calcium, lanthanum, tantalum oxide-nitrides [4]. Reproducibility, however, must be proven first. Their published properties, viz., brilliance of color coupled with nontoxicity, appear ideal for inclusion in the high-performance category.
A study of the “old fashioned” and almost forgotten workhorse pigment ultramarine blue could also be significant in the light of its revival through recently introduced new manufacturing technology. And so it is possible that, in the future, development of new manufacturing processes for “old” pigments and enhancement of their properties might well revitalize these products to the point where they could also join the ranks of truly high performance pigments.