Monastral fast blue

Depending upon the metallic compound used, different metallic phthalocyanine derivatives are obtained, e.g. when copper chloride is used copper phthalocyanine (Monastral Fast Blue B) is obtained. 

In Britain during 1932-1933, a major discovery took place at what would soon be an ICI acquisition, Scottish Dyes. By chance, a blue colorant was obtained during preparation of phthalimide from phthalic anhydride and ammonia. Though not an aromatic amino compound, the stable product is important in the history of dye discovery. It was a phthalocyanine compound, of the type first prepared in 1907. ICI manufactured the copper analogue, known as Monastral fast blue. Introduced in 1934, it represented the first member of the only new structural class of synthetic dye in the 20th century83. 

For item (2), the Vogel (1948) [45] and Fierz-David (1949) [46] plans for monastral fast blue B is an example of a deep-seated redox transformation. Two cuprous ions change their oxidation state from +1 to +2 while two nitrile carbons change their oxidation states from +3 to +2. 

Monastral fast blue B Fierz-David 1949 Convergent -471.1... 

Juarranz, A. Stockert, J. C. Monastral fast blue. Cytochemical properties of a reaction product from Alcian blue-stained chromatin. Acta Histochem. 1982, 70, 130-134. 

In the synthetic pigment field the discovery and introduction (1935) by ICI of copper phthalocyanine (Monastral Blue) set new standards in all-round fastness properties. 

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