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:
Aug. 04, 1987
Filed:
Aug. 17, 1984
Applicant:
Inventors:
Hiroshi Horino, Yokohama, JP;
Michiro Ohnaka, Kamakura, JP;
Atsushi Hayashi, Yokohama, JP;
Yoshiko Ikeno, Kawasaki, JP;
Assignee:
Nippon Zeon Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ; C07C / ; C07C / ;
U.S. Cl.
CPC ...
549240 ; 549243 ; 549246 ; 558416 ; 560146 ; 562480 ; 562471 ; 562473 ;
Abstract
A process for producing a substituted phthalic acid which comprises heating a substituted tetrahydrophthalic acid compound having a substituent in at least one of the 3-, 4-, 5- and 6-positions in the presence of sulfur to dehydrogenate it, and heat-treating the product in the presence of water optionally together with an organic solvent. As required, the heat-treated product is dehydrocyclized to form a substituted phthalic acid anhydride.