Polyester synthetic resin reaction system

Claim 1

PROCESS FOR PRODUCING A POLYESTER RESIN INCLUDING THE STEPS OF FORMING A REACTION MIXTURE FREE OF LIQUID HYDROCARBON DILUENTS AND CONTAINING AN ALIPHATIC POLYHYDRIC ALCOHOL AND AN ACIDIC MATERIAL SELECTED FROM THE GROUP CONSISTING OF ALIPHATIC POLYCARBOXYLIC ACIDS, AROMATIC POLYCARBOXYLIC ACIDS, ALIPHATIC POLYCARBOXYLIC ACIDS ANHYDRIDES AND AROMATIC POLYCARBOXYLIC ACID ANHYDRIDES, HEATING SAID REACTION MIXTURE IN A REACTION ZONE AT A TEMPERATURE SUFFICIENT TO FORM A POLYESTER RESIN AND WATER, SEPARATING FROM THE REACTION MIXTURE WATER AS IT IS EVOLVED, CONTINUING THE REACTION UNTIL THE RATE OF WATER EVOLUTION DECREASES, THEREUPON REMOVING A PORTION OF THE REACTION MIXTURE FROM THE REACTION ZONE, ADDING TO THE REMOVED PORTION OF THE REACTION MIXTURE AT A POINT OUTSIDE THE REACTION ZONE AN INERT LIQUID HYDROCARBON ENTAINING AGENT IN AN AMOUNT SUFFICIENT TO ENTRAIN SUBSTANTIALLY ALL THE WATER OF REACTION IN SAID REMOVED PORTION OF THE REACTION MIXTURE, SEPARATING FROM THE REMOVED PORTION OF THE REACTION MIXTURE SUBSTANTIALLY ALL OF THE WATER AND SUBSTANTIALLY ALL OF THE ENTRAINING AGENT, SAID ENTRAINING AGENT BEING SEPARATED AT LEAST IN PART AS AN AZEOTROPE WITH THE WATER AND RECOVERING THE POLYESTER THUS PRODUCT.