Chroma Archival Oil Color - Red Black, 40 ml tube

Pigment Information

This color contains the following pigments:

PBk7-Lamp Black

PR112-Naphthol Red AS-D

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

<p>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 considered slightly toxic. Avoid skin contact and inhalation. Where such impurities are present, Lamp Black is a possible human carcinogen.</p>

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

PR112-Naphthol Red AS-D

Pigment Type

organic, monoazo

Chemical Formula

C24H16Cl3N3O2

Properties

This Naphthol Red is an intense scarlet red pigment that is heavily staining. It has an average drying time. It is semi-transparent and has relatively poor covering power.

Permanence

This Naphthol Red has been rated as having excellent lightfastness under ASTM testing, but other testing methods have demonstrated some tendancy for the color to fade with exposure to strong ultraviolet light. It has been considered a replacement for less lightfast naphthol reds such as PR3. Not suitable for exterior use.

Toxicity

Naphthol Reds are not considered toxic. Naphthol Red AS-D may cause eye, skin, or respiratory irritation. Contact with dry pigment should be avoided.

History

Unknown.