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:
Jan. 19, 1982
Filed:
Dec. 31, 1979
Shozaburo Imai, Akashi, JP;
Haruo Suzuki, Ibaraki, JP;
Kuniaki Asai, Tondabayashi, JP;
Katsuji Ueno, Hirakata, JP;
Sumitomo Chemical Company Limited, Osaka, JP;
Abstract
In a process for producing aromatic polyesters by bulk condensation of polyester forming reactant the improvement which comprises using three reaction vessels, reacting a reactant compound with an acid anhydride to effect an alkanolylation reaction in the first reaction vessel to thereby prepare a monomer, removing the acids by-produced in said reaction, forming or not forming an oligomer from a part or whole of said monomer, then transferring the reaction product of the first vessel into the second reaction vessel, polycondensing said monomer and/or oligomer to produce a prepolymer in the second reaction vessel, transferring the reaction product of the second vessel into the third reaction vessel, and heating said prepolymer in said third reaction vessel, thereby obtaining an aromatic polyester of high polymerization degree.