Patent ID: 7553531

Claim:
A honeycomb structure, comprising: a plurality of honeycomb units bonded together by using a sealing material layer, each of the honeycomb units including a plurality of through-holes separated by a plurality of partition walls and provided in parallel along a longitudinal direction of the honeycomb units; wherein each of the honeycomb units includes at least ceramic particles, and inorganic fibers and/or whiskers; an area of a cross section of each of the honeycomb units perpendicular to the longitudinal direction of the honeycomb unit is greater than or equal to about 5 cm 2 and less than or equal to about 50 cm 2 ; and an outer surface of each of the honeycomb units and the sealing material layer satisfy: about 0.5 ≦κ/d× ( dc/κc+df/κf )≦about 1 where, κf (W/mK) represents a thermal conductivity of the outer surface of each of the honeycomb units, and df (mm) represents a thickness of the outer surface of each of the honeycomb units, κc (W/mK) represents a thermal conductivity of the sealing material layer, and dc (mm) represents a thickness of the sealing material layer, and κ (W/mK) represents a thermal conductivity of a combination of the outer surface and the sealing material layer, and d (mm) represents a thickness of the combination of the outer surface and the sealing material layer.