Pebeo XL Studio Oil Color - Glaze Payne's Gray, 180 ml tube

Pigment Information

This color contains the following pigments:

PR170-Naphthol Red

PBk7-Lamp Black

PB15:3-Phthalo Blue

Pigment Name

PR170-Naphthol Red

Pigment Type

organic, naphthol AS

Chemical Formula

C26H22N4O4

Properties

Pigment PR170 is a bright deep red with bluish undertones. It has an average drying time. It has two crystaline forms that differ significantly in opacity. The more transparent form (F5RK) tends to be more bluish and is less lightfast.

Permanence

The lightfastness and weatherfastness of Pigment PR170 varies, depending on the application and the crystaline form. The opaque form (F3RK) has very good lightfastness, and is more weather resistant. The transparent form (F5RK) has lightfastness that is considered acceptable in pure applications, but it fades more in tints. Neither form is considered suitable 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. Pigment Red PR170 is a Naphthol AS pigment, chemically related to the diarylide yellow pigments. The Naphthol AS pigments comprise a range of reds. They are used in plastics, textiles, and printing inks.

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

PB15:3-Phthalo Blue

Pigment Type

organic

Chemical Name

beta copper phthalocyanine

Chemical Formula

C32H16CuN8

Properties

Phthalo Blue PB15:3 is a structural variant of Phthalo Blue PB15 that produces more greenish 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.