Process of preparing self-extinguishing resinous polyesters based upon tetrabromophthalic anhydride

Claim 1

IN THE PROCESS FOR THE PREPARATION OF A POLYESTER RESIN BY REACTING AN ACIDIC COMPONENT COMPRISING TETRABROMOPHTHALIC ANHYDRIDE WITH A BASIC COMPONENT SELECTED FROM THE GROUP CONSISTING OF DI-AND POLYHYDRIC ALCOHOLS THE STEPS WHICH COMPRISE: (A) MIXING IMPURE, CRYSTALLINE TETRABROMOPHTHALIC ANHYDRIDE, CONTAINING CATALYTIC ACIDITY OCCLUDED IN THE CRYSTALS WHICH CAUSES THE FORMATION OF CYCLIC ETHERS AND ACETALS THROUGH THE CYCLIZATION OF THE BASIC COMPONENT SELECTED FROM THE GROUP CONSISTING OF DI- AND POLYHYDRIC ALCOHOLS AND WHICH IS PRODUCED BY THE BROMINATION OF PHTHALIC ANHYDRIDE IN OLEUM, WITH SMALL AMOUNTS OF AN ACID NEUTRALIZING MATERIAL SELECTED FROM THE GROUP CONSISTING OF INORGANIC AND ORGANIC BASES AND SALTS SUFFICIENT TO EFFECTIVELY NEUTRALIZE THE CATALYTIC ACIDITY RESULTING FROM THE OLEUM PRODUCTION OF THE TETRABROMOPHTHALIC ANHYDRIDE; AND (B) REACTING THE ACIDIC COMPONENT COMPRISING THE TETRABROMOPHTHALIC ANHYDRIDE CONTAINING THE ACID NEUTRALIZING MATERIAL WITH THE BASIC COMPONENT SELECTED FROM THE GROUP CONSISTING OF DI- AND POLYHYDRIC ALCOHOLS TO FORM THE POLYESTER RESIN, THE POLYESTER RESIN BEING FREE FROM CYCLIC ETHERS AND ACETALS PRODUCED THROUGH THE CYCLIZATION OF THE BASIC COMPONENT BY THE CATALYTIC ACIDITY IN THE OLEUM PRODUCED TETRABROMOPHTHALIC ANHYDRIDE AND HAVING A HIGH MOLECULAR WEIGHT.