| 摘要 |
PURPOSE:To provide the subject composition capable of being used as a substitute for conventional CFC and having excellent characteristics as a cleansing solvent, etc., containing tetrachloro-1,2-difluoroethane and perchloroethylene in a specific ratio. CONSTITUTION:An azeotropic composition comprises 97.7wt.% of (A) tetrachloro-1,2-difluoroethane and 2.3wt.% of (B) perchloroethylene, and a pseudoazeotropic composition comprises 92-99.9wt.% of a component A and 0.1-8wt.% of the component B. The compositions exist as azeotropic compositions and have larger cleansing powers than that of the conventional 1,1,2-trichloro-1,2,2-trifluoroethane. Since the change of the compositions are less than the conventional solvent even when the compositions are recycled, the compositions can be employed in the same manner as the conventional CFC and do not required the large change of conventional techniques. |
