HONEYCOMB STRUCTURE AND EXHAUST GAS PURIFIER

摘要

A honeycomb structure comprising a columnar honeycomb block including a honeycomb unit having a large number of cells juxtaposed in the longitudinal direction defined by cell walls and provided with a seal material on the outer circumference thereof. Protrusions and recesses are formed on the outer circumferential surface of the honeycomb structure and the honeycomb block. The honeycomb unit is composed of inorganic particles, inorganic fibers and/or whiskers and characterized in that a relation 0.3 mm = M1 is satisfied when the centroid of a least square curve determined on the basis of the points forming the outline of a cross-section perpendicular to the longitudinal direction of the honeycomb structure is c1, the distance between the concentric minimum circumscribed curve of the least square curve and the centroid c1 is D1, the distance between the concentric maximum inscribed curve of the least square curve and the centroid c1 is D2, and M1 = D1 - D2, and a relation 0.5 mm = M2 = 7.0 mm is satisfied when c2, D3 and D4 are determined similarly on the basis of the points forming the outline of a cross-section perpendicular to the longitudinal direction of the honeycomb block, and M2 = D3 - D4.