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:
PBr25—Benzimidazolone Brown
Pigment Type
organic, monoazo benzimidazolone
Chemical Name
n/a
Chemical Formula
n/a
Properties
Benzimidazolone Brown is a transparent brown pigment that is heavily staining and dark valued but has moderately low tinting strength. According to its manufacturer Clariant, “It is a dark brown, very transparent benzimidazolone pigment with excellent light, weather, and solvent fastness properties plus high heat stability. Recommended for paste inks, solvent and water based packaging gravure, and flexographic printing inks.” Benzimidazolone Brown has been used in watercolor painting, where transparent brown colors have traditionally been mixed from other pigments.
Permanence
Benzimidazolone Brown has excellent lightfastness and weather resistance.
Toxicity
n/a
History
Benzimidazolone pigments were developed and patented by Hoechst in 1960, and have gradually come into use as artist pigments.
Alternate Names
Renol Brown, Viscofil Brown, Microdis Brown, Hostaperm Brown HFR.
PY17—Permanent Yellow
Pigment Type
organic, disazo
Chemical Name
Benzidine Yellow GG
Chemical Formula
n/a
Properties
Pigment Yellow 17 is a somewhat greenish yellow that has very high tinting strength and good resistance to solvents.
Permanence
Pigment Yellow 17 has good lightfastness if prepared using the proper procedures. Because procedures for preparing PY17 vary, artists may want to conduct their own lightfastness tests to verify that the manufacturer has selected quality pigment.
Toxicity
Benzidine dyes are not bioavailable. Although benzidine-based dyes can be reduced to their amine precursors in vivo, creating a compound that is carcinogenic, benzidine dyes are believed to be so insoluble in water that they are unlikely to be absorbed in a quantity sufficient to be carcinogenic.
History
This Benzidine Yellow dye was first reported by Esitelty in 1949. Initiailly, it was reported to be less lightfast than yellow monoazo pigments, which limited its usefulness. A method for making Pigment Yellow 17 more permanent was patented in 1972 (United States Patent 3785843), and the improved dye became known as Permanent Yellow. Permanent Yellow 17 is widely used in printing inks, textile dyes, paints, plastics, and coatings.
Alternate Names
Benzidine Yellow GG, Diarylide Yellow 17
PBr9—Van Dyke Brown
Pigment Type
earth
Chemical Name
n/a
Chemical Formula
n/a
Properties
Van Dyke Brown is a transparent brown pigment made from organic humic substances like soil, peat, or brown coal. Its transparency makes it more ideal for glazing than umbers and ochres. True Van Dyke Brown can turn dark or fade upon prolonged exposure to sunlight and has a tendency towards grey when mixed with whites. It is no longer used by artists concerned with permanence, and it has been replaced by mixtures containing Transparent Brown and Burnt Sienna.
Permanence
Van Dyke Brown was impermanent in its original varieties, but modern pigments by this name are generally more permanent.
Toxicity
Van Dyke Brown has no significant hazards unless contaminated with silica.
History
The discovery of this pigment dates from the late 16th or early 17th century. It was renamed in the 18th century after the great Flemish painter Anthony Van Dyke, who loved this dark, transparent color. Van Dyke Brown is made from treated Cassel earth with 80-90% organic materials and iron, alumina, and silica.
Alternate Names
Cassel Brown, Cassel Earth, Caste Earth, Cologne Earth, Terra di Colonia. Rubens Brown is a variety of Van Dyke Brown.
