Patent ID: 9533294
Date: 2017-01-03
CPC Classifications: B01D,B01J,C04B,F01N

Claim:
1. A honeycomb structural body as a monolithic body made of cordierite comprising partition walls arranged in a lattice shape and a plurality of cells surrounded by the partition walls, wherein the honeycomb structural body comprises a plurality of cell density sections having a cell density changed stepwise in a radial direction from a central side to an outer peripheral side in a cross section which is perpendicular to an axial direction, a boundary wall is formed between the cell density sections which are adjacent to each other in order to partition off these cell density sections, the cell density sections comprise a high cell density section having a maximum cell density, excepting an outermost cell density section formed at an outermost side, and a low cell density section having a minimum cell density, excepting an innermost cell density section formed at an innermost side, and the honeycomb structural body satisfies a relationship of V−Va≧Vb+Vs, where reference character V indicates a volume of the honeycomb structural body if the overall honeycomb structural body is composed of the high cell density section only, reference character Va indicates a volume of the high cell density section, reference character Vb indicates a volume of the low cell density section, and reference character Vs indicates a volume of the boundary wall which separates the low cell density section from the cell density section formed immediately inside of the low cell density section.