Ceramic honeycomb filter, its production method, and plugging material for ceramic honeycomb filter

• US 20070039298A1
• Filed: 09/29/2004
• Published: 02/22/2007
• Est. Priority Date: 09/29/2003
• Status: Active Grant

• Current Assignee: Hitachi Metals (Thailand) Ltd.
• Original Assignee: Hitachi Metals (Thailand) Ltd.
• Inventors: Tokumaru, Shinya
• Granted Patent: US 7,691,167 B2
• Time in Patent Office: Days
• US Class Current: 55/523
• CPC Class Codes: B01D 46/2418 Honeycomb filters used for filtering exhaust gases of an internal combustion engine F01N3/022; ceramic honeycomb structures per se C04B38/0006
• CPC Class Codes: B28B 11/006 Making hollow articles or partly closed articles
• CPC Class Codes: F01N 2330/06 Ceramic, e.g. monoliths
• CPC Class Codes: F01N 3/0222 the structure being monolithic, e.g. honeycombs
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies
• CPC Class Codes: Y10S 264/48 Processes of making filters
• CPC Class Codes: Y10S 55/05 Methods of making filter
• CPC Class Codes: Y10S 55/10 Residue burned
• CPC Class Codes: Y10S 55/30 Exhaust treatment
• CPC Class Codes: Y10T 428/24149 Honeycomb-like

Abstract

A ceramic honeycomb filter comprising a sintered ceramic honeycomb body having porous partition walls defining flow paths, and plugs formed in predetermined flow paths for removing particulate matter from an exhaust gas passing through the porous partition walls, the sintered ceramic honeycomb body being formed by a cordierite-based ceramic material, at least part of the plugs comprising ceramic particles and an amorphous oxide matrix formed from colloidal oxide.

Claims

1. A ceramic honeycomb filter comprising a sintered ceramic honeycomb body having porous partition walls defining flow paths, and plugs formed in predetermined flow paths for removing particulate matter from an exhaust gas passing through said porous partition walls, said sintered ceramic honeycomb body being made of a cordierite-based ceramic material;

and at least part of said plugs comprising ceramic particles and an amorphous oxide matrix formed from colloidal oxide.

2. The ceramic honeycomb filter according to claim 1, wherein said ceramic particles are cordierite particles and/or amorphous silica particles.

3. The ceramic honeycomb filter according to claim 1, wherein said ceramic particles are pulverized powder of the same material as the sintered ceramic honeycomb body.

4. The ceramic honeycomb filter according to claim 1, wherein said colloidal oxide is colloidal silica and/or colloidal alumina.

5. A method for producing a ceramic honeycomb filter comprising a sintered ceramic honeycomb body having porous partition walls defining flow paths, and plugs formed in predetermined flow paths for removing particulate matter from an exhaust gas passing through said porous partition walls, comprising the steps of forming said sintered ceramic honeycomb body by a cordierite-based ceramic material, and heating a plugging material filled in predetermined flow paths of said sintered ceramic honeycomb body to a temperature of 1000°

C. or lower to form plugs bonded to said sintered ceramic honeycomb body.

6. The method for producing a ceramic honeycomb filter according to claim 5, wherein the bonding temperature of said plugging material is 500°

C. or lower.

7. The method for producing a ceramic honeycomb filter according to claim 5, wherein at least part of said plugs are formed by a plugging material containing ceramic particles and colloidal oxide.

8. The method for producing a ceramic honeycomb filter according to claim 5, wherein said ceramic particles are pulverized powder of the same material as the sintered ceramic honeycomb body.

9. A plugging material comprising ceramic particles and colloidal oxide.