Pigment Information
This color contains the following pigments:
PBk7-Lamp Black
PB15:1-Phthalo Blue
PB60-Indanthrene Blue
Pigment Name
PBk7-Lamp Black
Pigment Type
inorganic
Chemical Name
carbon
Chemical Formula
C
Properties
Lamp black is a very opaque, heavily staining black pigment that does not have much covering or tinting power. It is typically the most opaque black in watercolor form. Though a very pure black, it tends to muddy slightly in mixtures. Natural sources may be brownish or bluish in tone because of impurities. When used in oil paints, it is one of the slowest drying pigments, and should not be used in underpainting or applied in layers underneath other colors.
Permanence
Lamp Black is very lightfast and absolutely permanent. It is used in all techniques in permanent painting.
Toxicity
Carbon itself is not considered hazardous, however other combustion products that are hazardous are often present as impurities when Lamp Black is produced from natural materials. For this reason, commercial preparations of the pigment should be considere
History
Lamp Black is a carbon based black traditionally produced by collecting soot (known as lampblack) from oil lamps. It has been used as a pigment since prehistoric times. It is the black found in Egyptian murals and tomb decorations and was the most popular black for fresco painting until the development of Mars Black.
Pigment Name
PB15:1-Phthalo Blue
Pigment Type
organic
Chemical Name
alpha copper phthalocyanine
Chemical Formula
C32H16CuN8
Properties
Phthalo Blue PB15:1 is a structural variant of Phthalo Blue PB15 that produces more reddish tones.
Permanence
Phthalo Blues are completely lightfast and stable and are permanent for all paint uses. They are currently used in inks, coatings, and many plastics due to their stability and are considered a standard pigment in printing ink and the packaging industry.
Toxicity
Phthalo Blues have no significant hazards, although those made before 1982 contained some PCBs (polychlorinated biphenyls).
History
Developed by chemists using the trade name Monastral Blue, the organic blue dyestuff now known as Phthalo Blue was presented as a pigment in November 1935 in London. Its discovery was accidental. The dark color was observed in a kettle where a dye was being made from a British dyestuff plant. The demand for such a pigment came from commercial printers who wanted a cyan to replace Prussian Blue.
Pigment Name
PB60-Indanthrene Blue
Pigment Type
organic, vat dyes
Chemical Name
complex, insoluble anthraquinone
Chemical Formula
C28H14N2O4
Properties
Indanthrene Blue is a clear, clean, deep blue organic pigment. It has moderate to high tinting strength and is not as overpowering as Phthalo Blue. Hansa Yellow Deep, Benzimidazolone Orange, and Raw Umber are its best mixing complements.
Permanence
Indanthrene Blue is permanent with excellent lightfastness in both masstone and tints.
Toxicity
Indanthrene Blue varies in its acute toxicity, though toxicity is generally slight.
History
Indanthrene Blue is the oldest vat dye, discovered and patented in 1901 by Rene Bohn. It is considered the first anthraquinone vat dye, a group of dyes characterized by excellent lightfastness. The pigment originates from this dye.
