Honeycomb structure and method for manufacturing honeycomb structure

Abstract

A honeycomb structure has a longitudinal axis, a ceramic structure extending along the longitudinal axis and having a large number of cells partitioned by a partition, and a coating layer arranged on an outer surface of the ceramic structure. The main component of the coating layer is molten inorganic oxide.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:

FIG. 1 is a schematic view showing an exhaust gas purification device according to one embodiment of the present invention;

FIG. 2 is a vertical cross-sectional view showing a honeycomb structure according to one embodiment of the present invention;

FIG. 3 is a perspective view showing a porous ceramic member used in one embodiment of the present invention;

FIG. 4 is a side cross-sectional view showing a honeycomb structure accommodated in a casing; and

FIG. 5 is a vertical cross-sectional view showing an aggregation of porous ceramic members according to one embodiment of the present invention.

Claims

1. A honeycomb structure having a longitudinal axis, comprising: a ceramic structure extending along the longitudinal axis and having a large number of cells partitioned by a partition; anda coating layer arranged on an outer surface of the ceramic structure, wherein the coating layer contains molten inorganic oxide as a main component.

2. The honeycomb structure according to claim 1, wherein the content of the molten inorganic oxide in the coating layer is about 55 to about 95 mass %.

3. The honeycomb structure according to claim 3, wherein the molten inorganic oxide comprises one selected from the group consisting of molten silica, molten alumina, molten titania, and molten zirconia.

4. The honeycomb structure according to claim 3, wherein the molten inorganic oxide comprises at least either one of molten silica and molten alumina.

5. The honeycomb structure according to claim 1, wherein the molten inorganic oxide has an average particle diameter of about 20 to about 100 μm.

6. The honeycomb structure according to claim 1, wherein the molten inorganic oxide has a cross-section with circularity of about 0.9 or more.

7. The honeycomb structure according to claim 1, wherein the ceramic structure includes a plurality of porous ceramic members joined together by a bonding agent layer.

8. The honeycomb structure according to claim 1, wherein the ceramic structure is formed from a single porous ceramic member.

9. The honeycomb structure according to claim 1, wherein the ceramic structure is formed by bonding with a bonding agent a first plurality of porous ceramic members for forming a central portion of the ceramic structure and a second plurality of porous ceramic members for forming an outer portion of the ceramic structure.

10. The honeycomb structure according to claim 1, wherein the ceramic structure has two end surfaces, wherein each cell has openings in the two end surfaces, with one of the openings in each cell being sealed, and the partition functions as a particle capturing filter.

11. A method for manufacturing a honeycomb structure, the method comprising the steps configured to: prepare a coating agent containing a molten inorganic oxide, a binder, and a solvent;apply the coating agent to an outer surface of a ceramic structure including a longitudinal axis and a ceramic structure extending along the longitudinal axis and having a large number of cells partitioned by a partition; andform a coating layer by hardening the coating agent;wherein the coating agent contains the molten inorganic oxide as a main component.

12. The method according to claim 11, wherein the content of the molten inorganic oxide in the coating agent is about 40 to about 70 mass %.

13. The method according to claim 11, wherein the molten inorganic oxide comprises one selected from the group consisting of molten silica, molten alumina, molten titania, and molten zirconia.

14. The method according to claim 13, wherein the molten inorganic oxide comprises at least either one of molten silica and molten alumina.

15. The method according to claim 11, wherein the molten inorganic oxide has an average particle diameter of about 20 to about 100 μm.

16. The method according to claim 11, wherein the molten inorganic oxide has a cross-section with circularity of about 0.9 or more.

17. The method according to claim 11, further comprising the step configured to join a plurality of porous ceramic members with a bonding agent layer to form the ceramic structure.

18. The method according to claim 11, further comprising the step configured to joined together a first plurality of porous ceramic members having a predetermined shape and a second plurality of porous ceramic members having a predetermined shape by a bonding agent layer to form the ceramic structure, wherein a central portion of the ceramic structure is formed by the first plurality of porous ceramic members and an outer portion of the ceramic structure is formed by the second plurality of porous ceramic members.

19. The method according to claim 11, wherein the ceramic structure has two end surfaces, and each cell has openings in the two end surfaces, the method further characterized by the step configured to: seal one of the openings of each cell so that the partition functions as a particle capturing filter.