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:
May. 19, 1992
Filed:
Feb. 19, 1991
Chih-Hao M Tsang, Davison, MI (US);
Raymond E Bedford, Burton, MI (US);
General Motors Corporation, Detroit, MI (US);
Abstract
In a preferred method, particles of amorphous silica are used to provide a silica coating suitable for carrying dispersed catalyst particles for the treatment of diesel engine exhaust emissions. The silica coating is formed from a mixture consisting essentially of two groups of the fine silica particles of respective average sizes and size ranges which are virtually non-overlapping. The particles of the first of the two groups have a first average size sufficient to permit the particles of the first group (smaller group) to occupy voids between the particles of the second group (larger group) in a packed arrangement, and preferably the second group has a second average size which is at least 20 times greater than the first average size. Although particles of amorphous silica are preferred for use in forming a coating with improved adherence suitable for the treatment of diesel exhaust, the method of the invention is also useful to improve the adherence of coatings formed of other ceramics, such as alumina, titania, zirconia and zeolite.