Heat insulating member for end cone portion of exhaust gas conversion apparatus

A heat insulating member for an end cone portion of an exhaust gas conversion apparatus, comprising:

• a mat including laminated sheets each made of alumina-silica based ceramic fibers and having needled interconnections extending in a lamination direction and in a longitudinal direction of the sheets to laminate the sheets together;
• a composition of the ceramic fiber used in the mat is alumina:silica=60-80:40-20;
• and
• one of said needled interconnections forming an orientation angle A (h/s) ranging from 0.5 to 0.87, where h is a thickness of the mat and s is a length of the one of the needled interconnections extending across the mat,
• wherein, along a direction of the orientation angle A, the alumina-silica based ceramic fibers are entangled between the laminated sheets.