Patent ID: 8029591

Claim:
An inorganic fiber aggregate having a plurality of through holes formed therein comprising: inorganic fibers; and an inorganic material comprising glass that has a lower melting point than the inorganic fibers, wherein said inorganic fiber aggregate has the plurality of through holes passing therethrough and a wall portion that separates the plurality of through holes, a density of the plurality of through holes is at least about 0.16 holes/cm 2 and at most about 62 holes/cm 2 , the inorganic material which melted is provided to fix the inorganic fibers to each other, the inorganic fibers are fixed to each other by the melted inorganic material at the intersections of the inorganic fibers, the inorganic material is locally provided at the intersections of the inorganic fibers, and at least about 20% of all of the intersections of the inorganic fibers are fixed to each other.