Color Swatch created using heavy application/diluted application and was applied on cold press watercolor paper (150 lb) material.
This color contains the following pigments:
PR188 —Naphthol Red
Pigment Type
organic monoazo
Chemical Name
n/a
Chemical Formula
C33H24Cl2N2O6
Properties
This Naphthol Red is yellowish, with a high tinting strength and average drying time. It produces warmer shades and tints.
Permanence
This Naphthol Red has excellent lightfastness, though it is generally not considered adequate for exterior use.
Toxicity
Naphthol Reds are not considered toxic. They may cause eye, skin, or respiratory irritation. Contact with dry pigment should be avoided.
History
Naphthol pigments are actually dyes that are "laked" to form pigments. First developed by the German chemical company Hoechst A.G. before World War I, their use in artist paints began in the 1920s.
Alternate Names
Naphthal, Naphthol Bordeaux, Naphthol Carbamide, Naphthol Carmine, Permanent Carmine, Permanent Red.
PO62—Benzimidazolone Orange
Pigment Type
organic, monoazo
Chemical Name
n/a
Chemical Formula
C17H13ClN6O5
Properties
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.
Permanence
Benzimidazolone Orange has excellent lightfastness and outstanding heat and solvent stability for a monoazo pigment.
Toxicity
Benzimidazolone Orange is not considered toxic.
History
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.
Alternate Names
Permanent Orange, Benzimida Orange