This color contains the following pigments:
organic, naphthol AS
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.
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.
Naphthol Reds are not considered toxic. They may cause eye, skin, or respiratory irritation. Contact with dry pigment should be avoided.
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.
manganese ammonium pyrophosphate
(NH4)2Mn2(P2O7)2 - Mn3(PO4)2 * 3H2O or H4O7P2H3NMn
Manganese Violet is a semi-transparent, bluish-violet pigment with a discrete opacity and low tinting strength. It is the reddest of the violets, and it covers and dries well in oil and tempera. It also performs well in pastel, encaustic, and watercolor. Manganese Violet is not well suited for fresco or acrylic painting. There can be significant differences in color across brands. It shares similar properties with bluish shades of Cobalt Violet.
Manganese Violet has excellent permanence and lightfastness, and it is one of the most lightfast, balanced violets in watercolor form.
Manganese Violet is highly toxic if inhaled and moderately toxic if ingested.
This pigment was developed in 1868 by E. Leykauf to replace the more expensive Cobalt Violet. It was not offered as an artists’ pigment until 1890.