Phthalocyanine Blue Synthetic organic pigment

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.
Phthalocyanine Blue is a synthetic pigment known for its vibrant and stable blue color. This pigment is widely used in various industries, including the field of art, owing to its exceptional properties. It is synthesized through a complex chemical process. It is derived from phthalonitrile, a precursor compound, which undergoes cyclization reactions with metal salts, typically copper or cobalt. This process results in the formation of crystalline structures with intense blue hues. The pigment's stable molecular structure ensures resistance to light, heat, and chemicals, making it highly durable in various applications. One of the primary advantages of Phthalocyanine Blue is its colorfastness, which means it retains its vibrant blue hue over time, even in exposure to harsh environmental conditions. This quality makes it a preferred choice for artists, textile manufacturers, and the printing industry. Additionally, its non-toxic nature further enhances its appeal for use in consumer products like toys and cosmetics. Phthalocyanine Blue is available in several types, including Alpha and Beta forms, each offering variations in color and performance characteristics. 
Approximately 25% of all artificial organic pigments are phthalocyanine derivatives.^[32] Copper phthalocyanine dyes are produced by introducing solubilizing groups, such as one or more sulfonic acid functions. These dyes find extensive use in various areas of textile dyeing (Direct dyes for cotton), for spin dyeing and in the paper industry. Direct blue 86 is the sodium salt of CuPc-sulfonic acid, whereas direct blue 199 is the quaternary ammonium salt of the CuPc-sulfonic acid. The quaternary ammonium salts of these sulfonic acids are used as solvent dyes because of their solubility in organic solvents, such as Solvent Blue 38 and Solvent Blue 48. The dye derived from cobalt phthalocyanine and an amine is Phthalogen Dye IBN. 1,3-Diiminoisoindolene, the intermediate formed during phthalocyanine manufacture, used in combination with a copper salt affords the dye GK 161.

Copper phthalocyanine is also used as a source material for manufacture of Phthalocyanine Green G.

Other related and commercially available phthalocyanines blue pigments are:

·        Pigment Blue 16 – metal-free phthalocyanine

·        Pigment Blue 75 – cobalt phthalocyanine

·        Pigment Blue 79 – aluminum phthalocyanine.