| abstract |
The invention relates to a pigment preparation which contains the mono-azo pigment of formula (1) and 0.1 to 40% by weight, preferably 0.5 to 25% by weight, in particular 1.0 to 17.5% by weight, of a pigment dispersant, in relation to the weight of the mono-azo pigment of formula (I), which is composed of disazo compounds, at least 30% by weight of the disazo compounds forming an asymmetrical disazo compound of formula Y-X-A-X-Z (II), in which A stands for biphenylene, 3,3′-dichlorobiphenylene, 3,3′-dimethoxybiphenylene, 3,3′-dimethylbiphenylene or 2,2′-dichloro-3,3′-dimethoxybiphenylene; X stands for a —NH—CO—CH(COCH3)-N═N—, —N═N—CH(COCH3)-CO—NH— or —N═N— group; Y stands for substituted or unsubstituted phenyl, pyrazolin-5-on-4-yl, 1-phenyl-pyrazolin-5-on-4-yl, 2-hydroxynaphth-1-yl or 2-hydroxy-3-(phenylaminocarbonyl)naphth-1-yl, the substituents being C 1 -C 4 -alkyl, C 1 -C 4 -alkoxy, nitro, halogen or C 1 -C 4 -alkoxycarbonyl and having the meaning of Y, and the compounds being further substituted with a sulphonic acid group present as an ammonium salt. |