Gamblin 1980 Oils -andnbsp;PY74-Arylide (Hansa) Yellow: PG7-Phthalo Green (Chlorinated polychlorinated copper(II) phthalocyanine)

Permanent Green Light: The colour of the first shoots of spring grass-bright and warm.

Pigmentandnbsp;Composition and Permanence:andnbsp;

Pigment Name: PY74-Arylide (Hansa) Yellow

Pigment Type: monoazo

Properties

Pigment PY74 is one of the most commercially essential 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 sizes 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 than other yellow monoazo pigments, particularly in 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.

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2ndandnbsp;Pigmentandnbsp;Composition and Permanence:andnbsp;

Pigment Name: PG7-Phthalo Green

Pigment Type: Organic

Properties

Phthalo Green is a transparent, cool, bright, high-intensity colour used in oil and acrylics. It comes from a Phthalocyanine Blue pigment where most hydrogen atoms have been replaced with chlorine, forming highly stable molecules. It has similar pigment properties and permanence to Phthalo Blue.

It is slow drying and an excellent base colour for mixing a range of bright greens. Phthalo Green is considered an excellent alternative to Viridian because it is intense and mixes well, and can be used to emphasize mineral colours in various tints. However, its tinting strength is very high so it can overpower other colours. This pigment most closely resembles the discontinued and toxic Verdigris.

Permanence

Phthalo Greens are completely lightfast and resistant to alkali, acids, solvents, heat, and ultraviolet radiation. Due to their stability, they are currently used in inks, coatings, and many plastics and are considered a standard pigment in printing ink and the packaging industry.

Toxicity

Phthalo Green has no significant hazards, but it contained PCBs (polychlorinated biphenyls) until 1982.

History

This bright blue-green was developed in 1935 and has been used since 1938.