US Patent 7905952 Blue phthalocyanine pigment composition and its preparation

The invention pertains to pigment compositions comprising from 70 to 93%, preferably from 81 to 93%, of e copper phthalocyanine, from to 18% of an aminomethyl-substituted phthalocyanine, from 2 to 15% of an ammonium sulfonato phthalocyanine and less than 2% of other phthalocyanine compounds, preferably 5 made by wet-milling a mixture of a copper phthalocyanine and e copper phthalocyanine together with the aminomethyl-substituted phthalocyanine and a milling aid in an organic liquid and adding the ammonium sulfonato phthalocyanine before the milling aid and the organic liquid are separated from the wet-milled mixture.