Methanol → Quinacridone

Participants

Reaction Conditions

Reaction Steps

2,5-dianilino-terephthalic acid (one part) was dissolved in polyphosphoric acid (6.14 parts at 118.5%). The solution, already at 105° C., was heated to 133° C. for 3 hours then cooled to 100° C. and diluted to a fluid mass with water (0.5 parts). The solution was then drowned into methanol (11.6 parts) and the mixture heated at 125° C. for one hour to obtain a bluish red beta-phase quinacridone pigment.

Provenance & Evidence