| 摘要 |
Substantially pure methylthioninium chloride pentahydrate form A is prepared from methylthioninium chloride by phase equilibration of suspensions, crystallization or solvent evaporation, whereby the water content of the solvent corresponds to a water activity of at least 0.4 at 25°C, and controlled drying of said methylthioninium chloride pentahydrate form A within its stability ranges of humidity, pressure and temperature. |
