Parkhurst & Oliff
Ceramic honeycomb structural body
 Disclosed herein is a ceramic honeycomb structural body which has cells of a rectangular section in which the pitch ratio between the short side and the long side of the cells is substantially 1:.sqroot.3. A method of manufacturing a ceramic honeycomb structural body and a die for extruding a ceramic honeycomb structural body are also disclosed. The die comprises molding slits having a profile corresponding to a sectional profile of a ceramic honeycomb structural body and ceramic raw batch material supply holes through which a ceramic raw batch material is supplied to the molding slits, wherein the pitch ratio between the short side and the long side of the molding slits is substantially 1:.sqroot.3. Further, a rotary regenerator type ceramic heat exchanger composed of the ceramic honeycomb structural body is disclosed. 
NGK Insulators, Ltd.
B Y
B28B Y10T
inventional additional
Kiminari Tadaaki
Kato Matsuhisa