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:
Jun. 23, 1987
Filed:
Oct. 03, 1985
Applicant:
Inventors:
Achim Riemann, Marburg, DE;
Werner Ude, Darmstadt, DE;
Assignee:
Ronm GmbH, Darmstadt, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
568727 ; 568719 ; 568728 ;
Abstract
A method for making 9,9-bis-(4-hydroxyphenyl)-fluorene by reacting fluorenone with phenol at a temperature from 20.degree. to 100.degree. C. in the presence of sulfuric acid of a concentration higher than 70 percent and of a mercaptan, and particularly beta-mercaptopropionic acid, as acidic condensing agents.