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:
Feb. 22, 1977
Filed:
Jun. 20, 1975
Applicant:
Inventors:
Ferdinand List, Marl, DT;
Kurt Wember, Marl, DT;
Assignee:
Chemische Werke Huls Aktiengesellschaft, Marl, DT;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
2604 / ;
Abstract
Silica gel esterification catalysts which are mechanically stable and are highly abrasion free, particularly suitable for the esterification of dimethyl terephthalate, are prepared by impregnating silica gel in solutions of aluminum, titanium, zinc and tin compounds, separating the excess solutions and drying at elevated temperatures. The catalysts are further improved by treatment with a gaseous mixture of methanol and water.