- Method For Directly Producing Fine-Particle Diketopyrrolopyrrol Pigments
-
The invention relates to a method for directly producing fine-particle 1,4-diketopyrrolo[3,4-c]pyrrols of formula (1), wherein R1a, R1b, R2a and R2b independently represent hydrogen, halogen, C1-C4 alkyl, C1-C4 alkoxy, cyano or phenyl, said compounds being characterized by a maximum frequency distribution between 20 and 120 nm. According to the method, nitriles are reacted with succinic acid esters or lactames or enamines in an alkali medium to form a pigment salt, and then protolysis of the pigment alkali salt is carried out. Said method is characterized in that an effective quantity of a pigment dispersant of formula (II) is added during the protolysis of the pigment alkali salt. In formula (II), Q is a radical of an organic pigment from the group of perinone, quinacridone, quinacridonquinone, anthanthrone, indanthrone, dioxazine, diketopyrrolopyrrol, indigo, thioindigo, thiazineindigo, isoindoline, isoindolinone, pyranthrone, isoviolanthrone, flavanthrone or anthrapyrimidine pigments.
- -
-
Page/Page column 4
(2010/06/11)
-
- Heterocyclic compounds their preparation and use
-
The present invention relates to therapeutically active azacyclic or azabicyclic compounds, a method of preparing the same and to pharmaceutical compositions comprising the compounds. The novel compounds are useful as stimulants of the cognitive function of the forebrain and hippocampus of mammals and especially in the treatment of Alzheimer's disease.
- -
-
-