chlorophthalic Anhydride has two components, 3-chlorophthalic Anhydride & 4-chlorophthalic Anhydride:
(1)3-chlorophthalic Anhydride
      Used in the synthesis of 1-chloro anthraquinone and phthalocyanine, it can replace heavy pollution mercury production method. Over 10 Chinese manufacturers produce chloro anthraquinone, the annual consumption growth rate is about 5%. With the promotion of environmental standard, this method will become a high benefit and hi-tech project. It has great developing space.      
(2)4-chlorophthalic Anhydride
      4-chlorophthalic Anhydride is used in the synthesis of BPDA , monoether dianhydride, thioether dianhydride & diether dianhydride. Reacting with diamine in cyclization reaction, it can produce polyimide.
      4-chlorophthalic Anhydride is the best intermediate for polyimide , or used as intermediate of pesticide and medicine. The demand quantity of 4-chlorophthalic Anhydride may exceeds thousands tons. The consumption of Monochlorophthalic Anhydride will exceed ten thousands of tons.
      In China, most of 4-chlorophthalic Anhydride used in the synthesis of dianhydride and polyimide, the annual consumption is about one thousand ton and and above .