Method for producing pigment transparent preparations based on perylene-3,4,9,10-tetracarboxylic acid diimine

Abstract

The invention relates to a method for producing pigment transparent preparations based on perylene-3,4,9,10-tetracarboxylic acid diimine of (XXX) formula, wherein u is a number between 0 and 8, when u>0; E is a chlorine or bromine atom and if u>1, possibly the combination of said atoms. The inventive method consists in wet grinding a perylimide raw pigment of the (xxx) formula in an aqueous liquid medium in the presence of at least one pigment dispersing agent of a perylene dispersing agent group and P.V. derived dispersing agents with the aid of a ball grinding mill operating at a maximum volume power of 1.0 kW per litre by the action of a grinder whose diameter is equal to or less than 5 mm, at a temperature equal to or higher than 50° C., and in isolating the such obtained pigment preparation.

Dependencies are inferred from the claim text.