Phthalocyanine blue
Composition and Properties of Phthalocyanine Blue
Phthalocyanine blue is a modern synthetic organic pigment with the following formula:The pigment is unaffected by heat and chemicals and is extremely lightfast.
Names
Helio blue, astral blue, thalo bluePB 15, CI 74160Phthalic is a shortening of the word naphthalic from oriental naphtha = oil, -cyanine from Greek kuanos = dark blue.
Preparation of Phthalocyanine Blue
Phthalocyanine blue is prepared by heating a mixture of phthalic anhydride, urea, and copper chloride. The product is first washed in dilute caustic soda and then in dilute hydrochloric acid. It then becomes copper-phthalocyanine but is not conditioned as a pigment until it is dissolved in concentrated sulfuric acid and carefully washed in excess water and filtered.
History of Use
Phthalocyanine pigments were developed around the 1930s and have been widely used in many areas besides artists’ pigments. The excellent colouristic properties have earned them a place on the palette of many well-known painters such as Kandinsky, Yves Klein, Barnett Newman, Roy Lichtenstein, Jackson Pollock, etc.Barnett Newman, Who’s Afraid of Red, Yellow and Blue III, 1967-68, collection Stedelijk Museum Amsterdam.References (1) Defeyt, Catherine and Strivay, David, PB15 as 20th and 21st Artists’ Pigments: Conservation Concerns, in E‐Preservation Science (2014), 11. Available as pdf.(2) Video: The Discovery of a New Pigment-The Story of Monastral Blue by Imperial Chemical Industries, colorantshistory.org
