QUINACRIDONE SOLID SOLUTION PIGMENT AND ITS PRODUCTION METHOD

摘要

PROBLEM TO BE SOLVED: To obtain a quinacridone pigment having a higher transparency than a conventional one by a method easier and simpler than a conventional method. SOLUTION: A crude quinacridone solid solution pigment essentially containing unsubstituted quinacridone and 4,11-dichloroquinacridone is heated in a large excess amount of a liquid medium to give a quinacridone solid solution pigment which essentially contains unsubstituted quinacridone and 4,11- dichloroquincridone and the peak strengths of which at Bragg angles (2θ±0.2 deg.) of 26.7 deg., 13.3 deg., and 6.4 deg. are 5,000-7,500 cps, 2,100-6,500 cps, and 2,000-5,000 cps, respectively, in a powder X-ray diffraction diagram by CuKαcharacteristic X-ray (wavelength: 1.541Å).