초록 ▼

Very pure, transparent pigments of high color strength, of the formula [Figure] in which R is hydrogen or alkyl having 1 to 4 C atoms, X is chlorine and/or bromine and n is a number from 0 to 4 are obtained by converting the corresponding crude pigment to the sulfate, isolating the sulfate, liberati

Very pure, transparent pigments of high color strength, of the formula [Figure] in which R is hydrogen or alkyl having 1 to 4 C atoms, X is chlorine and/or bromine and n is a number from 0 to 4 are obtained by converting the corresponding crude pigment to the sulfate, isolating the sulfate, liberating the pure product from the sulfate by hydrolysis, separating off the pure product and dry milling the anhydrous material, with or without additives and with or without subsequent solvent finishing. These pigments are suitable for coloring paints and plastic compositions, especially for pigmenting metallic paints.

대표청구항 ▼

A process for the preparation of a perylene-3,4,9,10-tetracarboxylic acid diimide pigment of the formula [Figure] in which R is hydrogen or alkyl of from 1 to 4 carbon atoms, X is chlorine and/or bromine and n is a number of from 0 to 4, which comprises converting the corresponding crude pigment to

A process for the preparation of a perylene-3,4,9,10-tetracarboxylic acid diimide pigment of the formula [Figure] in which R is hydrogen or alkyl of from 1 to 4 carbon atoms, X is chlorine and/or bromine and n is a number of from 0 to 4, which comprises converting the corresponding crude pigment to its sulfate, isolating the sulfate, hydrolyzing the sulfate to liberate therefrom the pure pigment, separating off the pure pigment, and dry-milling the pure pigment, in its anhydrous state, with or without one or more solid additives and with subsequent solvent finishing.