This color contains the following pigments:
Benzimidazolone Orange is a staining, yellowish orange pigment that can become dull in tints. It has an average drying time, and it loses some of its intensity as it dries. The yellowish orange varieties are more transparent.
Benzimidazolone Orange has excellent lightfastness and outstanding heat and solvent stability for a monoazo pigment.
Benzimidazolone Orange is not considered toxic.
The benzimidazolone group of pigments was developed and patented in 1960 by Hoechst A.G., a German chemical manufacturer that was a forerunner of the pharmaceutical company Aventis. Use of benzimidazolone pigments in the auto industry, especially Benzimidazolone Orange, became common in the 1980s because they were common replacements for lead chromate pigments, which were phased out during this period.
cadmium sulfide and cadmium selenide
CdS × CdSe
Cadmium Orange was the first true orange and was made by mixing Cadmium Yellow with Cadmium Red. It is a pure hue with excellent opacity and low toxicity compared with its predecessors. It also has very high hiding power. The greatest tinting strengths are possessed by the deeper shades. Only the highest grades contain pure Cadmium Orange without barium mixed in it. Cadmium pigments have been partially replaced by azo pigments, which are similar in lightfasness to the cadmium colors, cheaper, and non-toxic.
Cadmium Orange has excellent permanence, but like many cadmium pigments, it will fade in fresco or mural painting. The deeper varieties of this pigment are the most permanent. The paler varieties have been known to fade when exposed to sunlight.
Cadmium Orange is a known human carcinogen. It is extremely toxic if inhaled and slightly toxic if ingested.
Cadmiums get their names from the Latin word cadmia, meaning zinc ore calamine, and the Greek word kadmeia, meaning Cadmean earth, first found near Thebes, the city founded by the Phoenician prince Cadmus. Metallic cadmium was discovered in 1817 by Friedrich Strohmeyer. It was used sparingly after its discovery due to the scarcity of cadmium metal.