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:
Oct. 17, 1995
Filed:
Aug. 08, 1994
Wacker-Chemie GmbH, Munich, DE;
Abstract
A process for continuously rendering finely divided, pyrogenic silica hydrophobic at low temperatures in the presence of a hydrophobicizing aid such as aliphatic alcohols having from 1 to 3 carbon atoms. The process of rendering silica hydrophobic is conducted at temperatures of from 60.degree. to 350.degree. C., and more preferably from 80.degree. to 150.degree. C., over a period of from 2 to 5 hours, and more preferably from 3 to 4 hours. The hydrophobicizing agents are known organohalosilanes and the preferred hydrophobicizing aid is methanol. The hydrophobicizing aid is used in amounts of from 2% to 15% by weight, and more preferably in amounts of from 2% to 10% by weight, based on the weight of silica used.