Sennelier Watercolour S1 Cinereous Blue (344)

Cinereous Blue (344) Phthalo Blue PB15:3 is a structural variant of Phthalo Blue PB15 that produces more greenish tones. Zinc White is the coolest white with 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 suitable for painting wet into wet, glazing, and scumbling. 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 watercolour techniques.

Pigment Name: Phthalo Blue PB15:3 

Phthalo Blue is a structural variant of Phthalo Blue PB15 that produces more greenish tones.

Chemical Name: beta copper phthalocyanine.

Permanence: Phthalo Blues are lightfast, stable, and permanent for all paint uses. 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 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 colour was observed in a kettle where a dye was made from a British dyestuff plant. The demand for such a pigment came from commercial printers who wanted a cyan to replace Prussian Blue.

Alternate Names: Phthalo Blue Green Shade, Winsor Blue Green Shade

Pigment Name: PW4—Zinc White.

Zinc White is the coolest white and 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 suitable for painting wet into wet, 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 sulphur in the air as Lead White does. It is precious for making tints with other colours. Unmixed Zinc White dries to a brittle and dry paint film that may crack over the years, so it is unsuitable 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 watercolour techniques. Chemical Name: zinc(II)-oxide.

Permanence: Zinc White has excellent 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 watercolour 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.

Alternate Names: Chinese White, French White, Permanent White, Silver White, Snow White, Zinc Oxide.