Gamblin 1980 Oils -andnbsp;PB15:2-Phthalo Blue (Copper phthalocyanine)

Phthalo Blue: Warm blue was first made for printmaking ink (cyan) to replace Prussian Blue in the 1920s. With clean, pure masstone and transparency, Phthalo Blue, like all modern colours, has high tinting strength.

Pigmentandnbsp;Composition and Permanence:andnbsp;

Pigment Name: PB15:2-Phthalo Blue (Copper phthalocyanine)

Pigment Type: Organic

Properties

Phthalo Blue PB15:1 is a structural variant of Phthalo Blue PB15 that produces more reddish tones.

Permanence

Phthalo Blues are completely 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 cyan to replace Prussian Blue.