Old Holland Classic Oil Color - Permanent Green, 40 ml tube

Pigment Information

This color contains the following pigments:

PB15-Phthalo Blue

PY74-Hansa Yellow

PW4-Zinc White

Pigment Name

PB15-Phthalo Blue

Pigment Type

organic

Chemical Name

copper phthalocyanine

Chemical Formula

C32H16CuN8

Properties

Phthalo Blues are pure and clean primary blues with superior covering power. They have a very high tinting strength and tend to overwhelm other pigments, but if color strength can be controlled, they make predictable mixed colors. In oil form, blues are very deep and slow drying. When mixed with other colors or if chlorine is added, Phthalo Blue quickly tends towards green. When using alone, mix with some white, as Phthalo Blue can be semi-transparent and almost black on its own. It is among the most compatible of modern colors with mineral colors and is considered more reliable than Prussian Blue, while sharing the same physical and color properties. Phthalo Blue is a good color for glazing.

Permanence

Phthalo Blues are completely lightfast and stable and are permanent for all paint uses. They are currently used in inks, coatings, and many plastics due to their stability and are considered a standard pigment in printing ink and the packaging industry.

Toxicity

Phthalo Blues have no significant hazards, although those made before 1982 contained some PCBs (polychlorinated biphenyls).

History

Developed by chemists using the trade name Monastral Blue, the organic blue dyestuff now known as Phthalo Blue was presented as a pigment in November 1935 in London. Its discovery was accidental. The dark color was observed in a kettle where a dye was being made from a British dyestuff plant. The demand for such a pigment came from commercial printers who wanted a cyan to replace Prussian Blue.

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.

Pigment Name

PW4-Zinc White

Pigment Type

inorganic

Chemical Name

zinc(II)-oxide

Chemical Formula

ZnO

Properties

Zinc White is the coolest white, and it has a cold, clean masstone and a slightly bluish tint. It has less hiding power and is more transparent than other whites. It dries slowly and is good for painting wet into wet and for glazing and scumbling. Zinc White is neither as opaque nor as heavy as Lead White, its covering power is not as good, and it takes much longer to dry. However, it does not blacken when exposed to sulfur in the air as Lead White does. It is very valuable for making tints with other colors. Unmixed Zinc White dries to a brittle and dry paint film that may crack over the years, so it is not good for frescoing. It is more transparent in acrylic form than Titanium White and is the most commonly used white with gouache. Chinese White is a version of Zinc White appropriate for opaque watercolor techniques.

Permanence

Zinc White has great permanence and lightfastness.

Toxicity

Zinc White is moderately toxic if ingested and slightly toxic if inhaled.

History

Though historians are divided on who first isolated the element zinc, they agree that it was first suggested as a white pigment in 1782. Zinc White was accepted as a watercolor in 1834 and was called Chinese White due to the popularity of oriental porcelain in Europe at the time. Ten years later, a suitable oil form was produced. By the early 20th century, it had improved to the point where it was an acceptable alternative to Flake White.