Holbein Artists' Soft Pastel - Yellow 1

Pigment Information

This color contains the following pigments:

PY55-Diarylide Yellow Deep

PY97-Permanent Yellow

Pigment Name

PY55-Diarylide Yellow Deep

Pigment Type

organic, disazo

Chemical Formula

C34H30Cl2N6O4

Properties

Diarylide Yellow Deep is a semi-transparent deep yellow pigment with high tinting strength.

Permanence

Diarylide Yellow Deep is less lightfst than other diarylide yellows, often rated fair. Its fightfastness has been rated only 5 on the blue wool scale (5-8).

Toxicity

Diarylide Yellow pigments have no significant acute hazards, but possible chronic hazards have not been well studied.

History

Pigment Name

PY97-Permanent Yellow

Pigment Type

organic, monoazo

Chemical Formula

C26H27ClN4O8

Properties

Permanent Yellow PY97 ranges from reddish yellow to greenish yellow with temperature shifts from cool to warm hues. It has good tinting strength and average to slow drying time. Similar in shade to Hansa Yellow 1, it offers much better fastness properties and good heat stability.

Permanence

Pigment PY97 has excellent lightfastness, particularly in the darker shades.

Toxicity

No significant acute hazards of PY97 are known, though 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. Permanent Yellow (PY97) represents a further development of this line, with the aim of producing a yellow pigment that is suitable for exterior use.