Rembrandt Soft Pastel - Permanent Green Deep 619.7, Full Stick

Pigment Information

This color contains the following pigments:

PB15-Phthalo Blue

PY42-Yellow Iron Oxide

PY184-Bismuth Yellow

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

PY42-Yellow Iron Oxide

Chemical Name

iron(III)-oxide, hydrated

Chemical Formula

Fe2O3 • H2O

Properties

Yellow Ochre provides artists with earthtones from cream to brown. It has good hiding power, produces a quick drying paint, and can be safely mixed with other pigments. Its transparency varies widely from opaque shades to more transparent ones, which are valued for their use as glazes. If gypsum is present, Yellow Ochre is not suitable for frescoing. (See Brown Ochre, PY43.) PY42 is made from synthetic iron oxides. PY43 is made from natural iron oxide.

Permanence

Yellow Ochre has excellent permanence because ochres are some of the most permanent pigments available.

Toxicity

Yellow Ochre is non-toxic unless it contains manganese.

History

Ochre comes from the Greek word ochros, meaning pale yellow. It was one of the first pigments to be used by human beings, and evidence of its use has been found at 300,000 year old sites in France and the former Czechoslovakia.

Pigment Name

PY184-Bismuth Yellow

Pigment Type

inorganic

Chemical Name

bismuth orthovanadate or bismuth vanadium oxide

Chemical Formula

BiVO4

Properties

Bismuth Yellow is an intense, light value, semi-opaque yellow pigment with good tinting strength.

Permanence

Bismuth Yellow has excellent lightfastness.

Toxicity

Bismuth orthovanadate is harmful if swallowed. It is irritating to the eyes, respiratory system, and skin. Exposure may cause conjunctivitis, rhinitis, and reversible irritation of the respiratory tract. More severe cases may cause bronchitis, bronchospas

History

Bismuth orthovanadate occurs naturally in several minerals. Although it was synthesized in the 1920s, it was not developed as a commercial pigment until the 1970s.