Production of dimethylaminomethyl copper phthalocyanine

摘要

The present invention provides a process for the production of dimethylaminomethyl copper phthalocyanine having an average of 1 to 4 dimethylaminomethyl groups per molecule which comprises reacting aminomethyl copper phthalocyanine having an average of 1 to 4 aminomethyl groups per molecule with formaldehyde and aqueous formic acid at a concentration of 2 to 60%, at atmospheric pressure, and at an elevated temperature.