| abstract |
Provided is a manufacturing technology of a quinacridone solid solution pigment, which can obtain a quinacridone solid solution pigment with a high chromaticity and a bluish hue of the coloring matter, and more preferably a quinacridone solid solution pigment whose particle size is controlled. Specifically, the present invention is a method for producing a quinacridone solid solution pigment, comprising the following steps: a step for producing a crude quinacridone solid solution, wherein diarylaminoterephthalic acid is mixed with diarylaminoterephthalic acid in polyphosphoric acid. Alkyl aryl amino terephthalic acid is subjected to co-cyclization reaction to obtain the crude quinacridone in the aqueous state containing water in the solid solution of unsubstituted quinacridone and 2,9-dialkyl quinacridone solid solution; drying process, drying the obtained crude quinacridone solid solution in a water-containing state, so that the moisture content is less than 1%, to obtain a powdery crude quinacridone solid solution; and, in a pigmentation process, the obtained powdery The crude quinacridone solid solution is heated in a liquid medium that does not dissolve the crude quinacridone solid solution. |