Patent ID: 8715579

Claim:
A honeycomb structure having a substantially circular-pillar-shape, comprising: at least one electrically conductive honeycomb unit comprising: walls extending along a longitudinal direction of the at least one electrically conductive honeycomb unit to define a plurality of through holes; a first electrode having a membranous shape and provided on an outer circumferential surface of the honeycomb structure; and a second electrode having a membranous shape and provided in a vicinity of a central axis of the honeycomb structure extending along the longitudinal direction, wherein the honeycomb structure has a region which is hollow and which is within a distance of a certain radius from a center of the substantially circular-pillar-shape, wherein the honeycomb structure has an exterior curved surface which defines the substantially circular-pillar-shape of the honeycomb structure, an interior curved surface which defines the region, wherein the first electrode is provided over a substantially entire exterior curved surface, wherein the second electrode is provided over a substantially entire interior curved surface, wherein the honeycomb structure is formed of a plurality of electrically conductive honeycomb units bonded by interposing an adhesive layer, and wherein each of the first electrode and the second electrode is formed in each of the plurality of electrically conductive honeycomb units.