Ronald E Sweet

US Patent:

39593258, May 25, 1976

Filed:

Sep 23, 1974

Appl. No.:

5/508653

Inventors:

Ronald L. Sweet - Westfield NJ

Assignee:

E. I. du Pont De Nemours and Company - Wilmington DE

International Classification:

C07F 108

US Classification:

2604381

Abstract:

The copper II salt of 4-chlorophthalic acid prepared by reacting 4-chlorophthalic acid or a monoalkali metal salt thereof with copper II ion in aqueous solution under conditions of controlled pH. The copper II salt of 4-chlorophthalic acid is useful as an intermediate in the preparation of chlorine-containing copper phthalocyanine pigment.

US Patent:

40353834, Jul 12, 1977

Filed:

Oct 6, 1975

Appl. No.:

5/619970

Inventors:

Ronald Lancelot Sweet - Westfield NJ

Assignee:

E. I. Du Pont de Nemours and Company - Wilmington DE

International Classification:

C09B 4710

US Classification:

2603145

Abstract:

Improved eutectic process for preparing polychloro copper phthalocyanine by chlorinating copper phthalocyanine in a reaction medium of molten inorganic metal halide and contacting the reaction medium with an aqueous medium to precipitate the polychloro copper phthalocyanine, wherein the improvement resides in adding a reducing agent to the reaction medium after the completion of the chlorination or to the aqueous medium prior to contact with the reaction medium. The improved process provides a highly chlorinated polychloro copper phthalocyanine which is substantially free of tetrachlorophthalimide impurity. The resulting polychloro copper phthalocyanine is a pure green compound useful as a high quality pigment for a variety of applications.