Patent ID: 8182598

Claim:
A method of coloring a color filtercomprising the step of adding a colorant to the color filter during the production thereof, wherein the colorant includes a pigment preparation comprising a) a dioxazine compound of the formula (I) as base pigment and b) a dioxazine compound of the formula (II) as pigment dispersant Q-[Y—X] m (II) wherein Q is an m-valent radical of the base pigment of the formula (I), Y is a bridging moiety from the series —(CR 1 R 2 ) x — with x being 1 to 6, substituted or unsubstituted phenylene, —CO—, or —NR 3 —, or a nonrepeating or repeating combination of at least two such bridging members of different type, R 1 , R 2 , and R 3 independently of one another being hydrogen or C 1 -C 4 -alkyl, X is the radical of an aliphatic or aromatic, five-, six- or seven-membered heterocyclic system attached to the bridging member Y via a C atom and has in each case 1 to 3 identical or different ring heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur and, optionally, also has a benzo-fused ring optionally substituted by C 1 -C 4 -alkyl, C 2 -C 4 -alkenyl, C 1 -C 3 -hydroxyalkyl or phenyl; or is a phthalimido radical attached to the bridging member Y via the imide nitrogen and and is optionally substituted up to a maximum of four times on the benzoid ring by chloro, bromo, nitro, carboxyl, N—(C 1 -C 5 -alkyl)carbamoyl, N-phenylcarbamoyl or benzoylamino; or is a radical —NR 4 R 5 , in which R 4 and R 5 independently of one another are hydrogen, substituted or unsubstituted C 1 -C 20 -alkyl or C 2 -C 20 -alkenyl, C 5 -C 6 -cycloalkyl, substituted or unsubstituted phenyl, benzyl or naphthyl; or in which the group —NR 4 R 5 forms an aliphatic or aromatic, five-, six- or seven-membered heterocyclic system having in 1 to 3 identical or different ring heteroatoms selected from the group consisting of nitrogen, oxygen and sulfur, and, optionally, also has a benzo-fused ring optionally substituted by hydroxyl, oxo, C 1 -C 4 -alkyl, C 2 -C 4 -alkenyl, C 1 -C 3 -hydroxyalkyl or phenyl, and m indicates a numerical value between 1 and 4 wherein the pigment dispersant is a compound of the formula (III)