Patent ID: 7967906
Filing Date: 2011-06-28
Classification: B82Y,C09B,C09D

Abstract:
1. A process for direct production of finely divided 1,4-diketopyrrolo[3,4-c]pyrroles of formula (I) wherein a maximum of the frequency distribution of the crystalline particles of the 1,4-diketopyrrolo[3,4-c]pyrroles of formula (I) is between 30 and 130 nm, wherein R or reacting 1 mol of a lactam of formula (III) or of an enamine of formula (IV) with one mole of a nitrile of the formula R in an inert organic solvent in the presence of an alkali metal or of an alkali metal alkoxide as a strong base at elevated temperature to form a pigment alkali metal salt and subsequently releasing a compound of formula (I) by protolysis, wherein the protolysis is characterized in that the pigment alkali metal salt is added to a liquid protolysis medium in which a pigmentary dispersant of formula (II) has been dissolved or suspended, wherein the amount added of the pigmentary dispersant of formula (II) is at least 0.05% by weight, based on the weight of the pigment of formula (I) wherein Q is a residue of an organic pigment selected from the group consisting of perinone, quinacridone, quinacridonequinone, anthanthrone, indanthrone, dioxazine, diketopyrrolopyrrole, indigo, thioindigo, thiazineindigo, isoindoline, isoindolinone, pyranthrone, isoviolanthrone, flavanthrone and anthrapyrimidine pigments; s is from 1 to 5; n is from 0 to 4; subject to the proviso that the sum total of s and n is from 1 to 5; R R G