M. Graham Artists' Acrylics - Azo Yellow, 2 oz tube

Pigment Information

This color contains the following pigments:

PY151-Benzimidazolone Yellow

PY74-Hansa Yellow

Pigment Name

PY151-Benzimidazolone Yellow

Pigment Type

oranic, monoazo

Properties

Benzimidazolone Yellow is a greenish yellow pigment with dull tints and an average drying time. It mixes very cleanly. It mixes cleanly with both Phthalo Green and Titanium White. Although more expensive than many Hansa and Diarylide pigments, its mixing properties, durability, and lightfastness have won it many customers.

Permanence

Benzimidazolone Yellow has excellent lightfastness and durability. This has made it an extremely important pigment in the printing industry, for applications where lightfastness is a primary consideration. Though it is not absolutely lightfast, it ranks extremely well among organic yellows.

Toxicity

Benzimidazolone Yellow is not considered toxic.

History

The benzimidazolone group of pigments was developed and patented in 1960 by Hoechst A.G., a German chemical manufacturer that was a forerunner of the pharmaceutical company Aventis.

Pigment Name

PY74-Hansa Yellow

Pigment Type

monoazo

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.