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:
Jan. 11, 2005
Filed:
Apr. 23, 2002
Fredrick W. Vance, Midland, MI (US);
Sten A. Wallin, Midland, MI (US);
Fredrick W. Vance, Midland, MI (US);
Sten A. Wallin, Midland, MI (US);
Dow Global Technologies Inc., Midland, MI (US);
Abstract
A ceramic honeycomb wall-flow filter is prepared by plugging channels in a clay containing ceramic honeycomb by a method that has the following steps. First, a mixture of a dispersing liquid and ceramic powder is formed. Second, the mixture is inserted into at least one channel of a clay containing green ceramic honeycomb to form a plugged green ceramic honeycomb wherein the dispersing liquid essentially fails to swell the clay. Alternatively, the mixture is inserted into a calcined ceramic honeycomb to form a plugged calcined ceramic honeycomb. Finally, the plugged green or calcined ceramic honeycomb is heated to a temperature sufficient to sinter the plugged green ceramic honeycomb to form a porous sintered plugged ceramic honeycomb. The method is particularly useful for simultaneously making the plugs and discriminating layers in the channels. In particular the method is useful to make wall-flow filters having plugs on at least one end with same composition as the discriminating layer or plugs on each end having different compositions.