Color Swatch created using heavy application/medium application/50% tint and was applied on acrylic primed canvas (7 oz) material.
This color contains the following pigments:
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 considered slightly toxic. Avoid skin contact and inhalation. Where such impurities are present, Lamp Black is a possible human carcinogen.
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.
Alternate Names
Carbon Black, Channel Black, Furnace Black, Oil Black, Vegetable Black. Flame Black is an impure version of Lamp Black. An alternate spelling is Lampblack, in which the first syllable is stressed and the two words are elided to form a closed compound.
PR57—Lithol Rubine
Pigment Type
organic, monoazo
Chemical Name
n/a
Chemical Formula
C18H12N2O6, sodium salt
Properties
Lithol Rubine is a deep transparent red dye, generally slightly bluish, that is laked as a salt with sodium or calcium to form a pigment. PR57 is the sodium salt, and has a more bluish tone. PR57:1 is the calcium salt, and is the most widely used. Lithol Rubine makes clean pinks when tinted. Sources vary greatly in hue and transparency. Lithol Rubine has high tinting strength.
Permanence
Lightfastness is considered only fair to good. Superior products are available when lightfastness is paramount. Where greater lightfastness is needed in process color printing, the more expensive pigment PR184, a Naphthol AS pigment, is often substituted for Lithol Rubine.
Toxicity
Lithol Rubine is not considered toxic. It is used in food, drugs, and cosmetics, such as lipstick. It can be used in art materials intended for children.
History
Lithol Rubine pigments (especially the calcium salt PR57:1) are widely used in inks, paints, plastics, and textiles. Lithol Rubine is widely used as magenta in process color printing.
Alternate Names
4B Toner, Pigment PR57:1 is also known as D&C Red No 7, Ruby Red, Brilliant Carmine.
PY74—Hansa Yellow
Pigment Type
monoazo
Chemical Name
n/a
Chemical Formula
C18H18N4O6
Properties
Pigment PY74 is one of the most commercially important pigments of the Hansa Yellow group, considered superior to many others in its class based on both tinting strength and lightfastness. Several PY74 grades with different particle sizes are available. Grades with finer particle size are more brilliant and transparent. Pigment PY74 ranges from reddish yellow to greenish yellow, with temperature shifts from cool to warm hues. It has high tinting strength and average to slow drying time.
Permanence
This Hansa Yellow has better lightfastness that other yellow monoazo pigments, particularly in the darker shades.
Toxicity
Hansa Yellow has no significant acute hazards, though its chronic hazards have not been well studied.
History
Hansa Yellows were first made in Germany just before WW1 from a series of synthetic dyestuffs called Pigment Yellow. They were intended to be a synthetic replacement for Cadmium Yellow.
Alternate Names
Arylide, Arylide Yellow, Azo, Brilliant Yellow, Monoazo, Monolite Yellow, Permanent Yellow.
