The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 12, 1983
Filed:
Aug. 12, 1982
Applicant:
Inventor:
Chen-i Lu, Webster, NY (US);
Assignee:
Eastman Kodak Company, Rochester, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528274 ; 528272 ; 528480 ; 528495 ; 528499 ;
Abstract
A polyester prepolymer having increased reactivity when subjected to molecular weight buildup, such as in solid phase polymerization is prepared by an improved method which includes the steps of: reacting a dicarboxylic acid and a glycol in the presence of a transesterification catalyst to form a reaction mixture containing condensation oligomers; purifying the reaction mixture to remove substantially all of the reaction by-products and residual dicarboxylic acid, glycol and catalyst and to crystallize the condensation oligomers; and polycondensing the oligomers to form a molten prepolymer.