D185 Metallic Blue/Bleu Métallique - Phthalo Blue PB15:3 (organic copper Phthalocyanine), Mica PW20 (inorganic, aluminum silicate)

Series: A

Lightfast: ***

Pigment 1: Phthalo Blue PB15:3

Phthalocyanine Blue B NCNF is a bright green shade of blue possessing all the high resistance properties of the other PB 15 pigments. This version, like PB 15:2, has been treated to prevent flocculation of the pigment particles. It is used primarily in liquid inks and is also useful as a process colour cyan.

Phthalocyanine Blues was 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 being made from a British dyestuff plant. The demand for such a pigment came from commercial printers who wanted cyan to replace Prussian Blue.

Pigments Name: PB15-Phthalo Blue

Pigment Type: organic

Chemical Name: copper phthalocyanine

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 colour strength can be controlled, they make predictable mixed colours. In oil form, blues are intense and slow drying. When mixed with other colours 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 colours with mineral colours and is considered more reliable than Prussian Blue while sharing the same physical and colour properties. Phthalo Blue is a good colour 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).

Alternate Names: Bocour Blue, Cyan Blue, Helio Blue, Heliogen Blue, Intense Blue, Monastral Blue, Phthalocyanine Blue, Rembrandt Blue, Thalo Blue, Winsor Blue.

Pigment 2: Mica PW20

Mica has been used as a pigment since prehistoric times.

Pigment name: PW20 Mica

Pigment Type: Inorganic

Chemical Name: Aluminum silicate

Properties: An off-white pigment with complex reflective effects, mica is often used with transparent pigments to create mixed pigments with interference and pearlescent effects.

Permanence: Mica is permanent and lightfast.

Toxicity: Although it is entirely non-toxic and not bio-reactive, fine particles may be irritating: This is of concern primarily for those exposed occupationally to dry mica powder. Breathing mica particles may cause lung fibrosis and pneumoconiosis.

Alternate Names: n/a