摘要:
The invention relates to a method for producing transparent dioxazine pigments. Said method is characterised by the use of an eccentric oscillating mill to crush a dioxazine crude pigment, said mill comprising at least one milling container that is mounted on the oscillating elements and an excitation unit that is rigidly fixed to said milling container. According to the invention, the excitation takes place in an eccentric manner on one side, outside the gravitational axis and the centre of mass of the milling container, thus generating inhomogeneous oscillations consisting of circular, elliptical and linear oscillations.
摘要:
The invention relates to a process for preparing N,N′-dimethylperylene-3,4,9,10-tetracarboxylic diimide, utilizing the reaction of perylene-3,4,9,10-tetracarboxylic dianhydride with monomethylamine, which comprises employing at least 2 times the molar amount of monomethylamine per mole of perylene-3,4,9,10-tetracarboxylic dianhydride and at least 3 times the amount by weight of water based on the weight of the dianhydride, conducting the reaction at a temperature from 50 to 200° C., removing unreacted monomethylamine by distillation, subjecting the resulting crude pigment to wet grinding in a liquid, aqueous or aqueous-organic medium in a stirred ballmill which is operated with a power density of more than 1.5 kW per liter of milling space and a stirrer tip speed of more than 12 m/s under the action of grinding media having a diameter of less than or equal to 0.9 mm, and isolating the pigment obtained, with the proviso that at any desired point during the process, but no later than during wet grinding, one or more additives from the group consisting of pigment dispersants and surfactants are added.
摘要:
The invention relates to novel quinacridone mixed crystal pigments consisting of a) from 82.5 to 99% by weight of unsubstituted &ggr;-phase quinacridone of the formula (I) in which R1 and R2 are hydrogen atoms and b) from 1 to 17.5% by weight of one or more 2,9- and/or 3,10-substituted quinacridones of the formula (I) in which the substituents R1 and R2 are identical or different and are chlorine, bromine or fluorine atoms or C1-C4-alkyl, C1-C4-alkoxy or carboxamido groups which can be substituted by C1-C6-alkyl groups, and R1 can additionally be a hydrogen atom, and to pigment preparations comprising said quinacridone mixed crystal pigments.
摘要:
Linear unsubstituted and substituted quinacridone pigments and quinacridone mixed-crystal pigments are obtained by cyclizing dianilinoterephthalic acid with polyphosphoric acid and then hydrolyzing the ring closure mixture, said mixture being metered into an amount of water or orthophosphoric acid which is such that the final orthophosphoric acid concentration is greater than or equal to 50% by weight in the hedrolysis mixture.
摘要:
Mixed crystal pigments of the quinacridone series New quinacridone mixed crystal pigments consisting ofa) from 85 to 99% by weight of unsubstituted .beta.-phase quinacridone of the formula (I) ##STR1## in which R.sup.1 and R.sup.2 are hydrogen atoms and b) from 1 to 15% by weight of one or more substituted quinacridones of the formula (I) in which the substituents R.sup.1 and R.sup.2 are identical or different and are chlorine, bromine or fluorine atoms or C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or carboxamido groups which can be substituted by C.sub.1 -C.sub.6 -alkyl groups, and R.sup.1 may additionally be hydrogen, are valuable quinacridones in the red-violet range.
摘要:
The use of mixed-crystal pigments of the quinacridone series consisting of a) from 85 to 99% by weight of unsubstituted &bgr;-phase quinacridone of the formula (I) in which R1 and R2 are hydrogen atoms, and b) from 1 to 15% by weight of one or more substituted quinacridones of the formula (I) in which the substituents R1 and R2 are identical or different and are chlorine, bromine or fluorine atoms or C1-C4-alkyl, C1-C4-alkoxy or carboxamido groups, which can be substituted by C1-C6-alkyl groups, and R1 can additionally be hydrogen, as colorants in electrophotographic toners and developers, powder coating materials, inkjet inks, electret fibers, and color filters.