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:
Dec. 07, 1982
Filed:
Dec. 03, 1981
Senzo Shimizu, Odawara, JP;
Isao Nomura, Hiratsuka, JP;
Motohachi Usui, Odawara, JP;
Mashahiro Harada, Hiratsuki, JP;
Mitsubishi Gas Chemical Co., Inc., Tokyo, JP;
Abstract
A process for producing an aromatic polyester copolymer wherein the alternating configuration of the components making up the copolymer is highly regular, said process comprising a first step of reacting a dihydric phenolic compound with an aromatic dicarboxylic acid dichloride A in a reaction medium consisting of water and a water-immiscible solvent in the presence of a basic inorganic compound to give a phenolic hydroxyl-terminated aromatic oligoester containing predominantly an oligomer having a degree of polymerization of 1-2, and a second step of reacting the aromatic dihydroxy oligoester obtained in the first step with an aromatic dicarboxylic acid dichloride B in the presence of a basic inorganic compound in an amount at least sufficient to neutralize the free phenolic hydroxyl groups remaining in the reaction product mixture obtained in the first step.