Color Swatch created using full strength/50/50 and was applied on cold press Bristol board (2 ply) material.
This color contains the following pigments:
PR9—Naphthol Red
Pigment Type
monoazo
Chemical Name
n/a
Chemical Formula
C24H17Cl2N3O3
Properties
This Naphthol Red is a bright deep red with bluish undertones. It has an average drying time.
Permanence
This Naphthol Red has fair to good lightfastness, not because of its masstone, but because it fades in tints. Not 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
Unknown.
Alternate Names
Naphthal, Naphthol Bordeaux, Naphthol Carbamide, Naphthol Carmine, Permanent Carmine, Permanent Red.
PR4—Permanent Red
Pigment Type
organic, monoazo
Chemical Name
n/a
Chemical Formula
n/a
Properties
Pigment PR4 is an opaque, bright yellowish red pigment with high tinting strength.
Permanence
Pigment PR4 has good lightfastness, but newer red pigments are considered more permanent and reliable.
Toxicity
Known also as D&C Red No 36, PR4 is used in cosmetic products such as lipsticks. It has been tested for carcinogenic and mutagenic effects in laboratory rats.
History
Because it is inexpensive and has a long history of use in cosmetic products, Permanent Red PR4 is widely used in artist materials where safety is more important than archival preservation, as in children's art materials.
Alternate Names
Blazing Red, Flaming Red, D&C Red No 36.