Patent ID: 6723138
Filing Date: 2004-04-20
Classification: B01J,C09B,F28F,Y10T

Abstract:
A process for coloring a composition comprising adding at least one 1,4 diketopyrrolo[3,4-c]pyrrole pigment of the formula (I) wherein R1 and R2 are identical or different and are each an unsubstituted or substituted isocyclic or heterocyclic aromatic radical, to a composition selected from the group consisting of an electrophotographic toner, an electrophotographic developer, a powder coating, an aqueous basis of an inkjet ink, a non-aqueous basis of an inkjet ink and a color filter, wherein the 1,4 diketopyrrolo[3,4-c]pyrrole pigment of the formula (I) is prepared by reacting a succinic diester with a nitrile of the formula (II)R1â€”CNâ€ƒâ€ƒ(II) or of the formula (III)R2â€”CN (III) or with a mixture of these nitrites, in an organic solvent and in the presence of a strong base, and subsequently conducting hydrolysis of the resultant salt of the diketopyrrolopyrrole pigment, which comprises conducting the reaction, or the hydrolysis, or the reaction and the hydrolysis, in a microreactor having clear width channel dimensions between about 10 &mgr;m and about 800 &mgr;m.