| 摘要 |
PURPOSE:To obtain the subject incombustible composition usable as a substitute of fluorocarbon having characteristics comparable to or superior to the characteristics of conventional fluorocarbons and consisting of at least two components selected from R225ca, R225cb, R224ca and chloroform. CONSTITUTION:The composition consisting of at least two components selected from a group of (A) 3,3-dichloro-1,1,1,2,2-pentafluoropropane (R225ca), (B) 1,3- dichloro-1,1,2,2,3-pentafluoropropane (R225cb), (C) 1,3,3-trichloro-1,1,2,2- tetrafluoropropane (R224ca) and (D) chloroform. The abovementioned component is e.g. obtained by reacting tetrafluoroethylene with dichlorofluoromethane or chloroform in the presence of a Lewis acid catalyst and separating compounds having high boiling point from the reaction product. Furthermore, the composition preferably consists of 50 to 100wt.% sum of the components A and B, 0 to 25wt.% component C, and 0 to 25wt.% component D. |
