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The cadmium and lead salts (along with organic colorants) especially pigments used for coloration of thermo-plastic polymers, have been regarded as technological and functional necessities in nearly every sphere of our daily lives. They also greatly influence our mood and thus contribute enormously to the very quality of the lives we lead. At the same time, we have come to realize that our achievements and continuing technological progress are only worthwhile provided they pose no hazard to the environment as well as human life. The regulatory agencies, corporate laboratories, customers, consumers and employees alike have identified problems with lead and cadmium colorants. To meet these challenges, a color chemist must become familiar not only with what pigments are available, but how they differ from one another. The use of environmentally safer colorants are a trend for the 1990's. Monsanto has been exploring alternates to cadmium pigments in their resins for several years.

Colorfastness of an ASA polyblend in ten colors was studied using accelerated weathering and outdoor under-glass (UG) exposure. For nine colors, the exposure required to reach an average delta E of 1.9 based on 0.6 MJ/m2/nm @ 340 nm in the 89°C Xenon arcs (GM conditions) was: 0.53 months for the 89°C Xenon; 1.13 months, the 63°C Xenon (ASTM); 6.1 months, Arizona UG; 28.1 months, Florida UG. For one color, the light yellow, a reversal was observed, showing extensive color change in the 63°C Xenon and Florida UG but little color change in the 89°C Xenon and Arizona UG. UVCON (UVB) did not correlate with the Xenons, however. Limited information on the Xenon arcs weathering and Florida direct exposure on color and gloss changes is also presented.