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:
PR170—Naphthol Red
Pigment Type
organic, naphthol AS
Chemical Name
n/a
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.
Alternate Names
Naphthal, Naphthol Bordeaux, Naphthol Carbamide, Naphthol Carmine, Permanent Carmine, Naphthol Crimson, Permanent Red, Permanent Red F3RK (more opaque), Permanent Red F5RK (more transparent).
PR179—Perylene Maroon
Pigment Type
organic, anthraquinone
Chemical Name
n/a
Chemical Formula
C26H14N2O4
Properties
Perylene Maroon is a transparent, dull to moderately dull, deep red pigment. Its transparency makes it useful as a glazing color. Its mixing complement is Phthalo Green, and together they produce a pure black that is darker than most carbon-based pigments. Perylene Maroon is not suitable for acrylics.
Permanence
Perylene Maroon has excellent permanence and lightfastness, and it can be an appropriate replacement for Anthraquinone Red in watercolor form.
Toxicity
Perylene Maroon has no significant acute toxicity. Its long term hazards are currently unknown.
History
Perylenes have been used as vat dyes since 1912, but they were not manufactured and sold as pigments until 1957.
Alternate Names
Perylene.
PR209—Quinacridone Red
Pigment Type
organic, quinacridone
Chemical Name
n/a
Chemical Formula
n/a
Properties
Quinacridone Red is a bright, clean red pigment with average drying time. Quinacridone pigments have relatively low tinting strength in general. For this reason, quinacridone colors are often expensive, because more pigment is required in the formulation.
Permanence
Quinacridone Red has excellent permanence and lightfastness.
Toxicity
Quinacridone Red has no known acute hazards. Overexposure to quinacridone pigments may cause skin irritation. Quinicridone pigments contain a compound found to be a skin, eye, and respiratory irritant.
History
Although quinacridone compounds became known in the late 19th century, methods of manufacturing so as to make them practical for use as commercial pigments did not begin until the 1950s. Quinacridone pigments were first developed as coatings for the automotive industry, but were quickly adopted by artists.
Alternate Names
n/a
