Pebeo Studio Gouache - Carmine, 100 ml Tube

Pigment Information

This color contains the following pigments:

PR57:1-Lithol Rubine

PR4-Permanent Red

Pigment Name

PR57:1-Lithol Rubine

Pigment Type

organic, monoazo

Chemical Formula

C18H12N2O6, calcium salt

Properties

Lithol Rubine (PR57:1) 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. Pink lipstick is often manufactured with pigment PR57:1. Lithol Rubine 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.

Pigment Name

PR4-Permanent Red

Pigment Type

organic, monoazo

Chemical Formula

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.