Patent ID: 7541303

Claim:
A batch composition for the manufacture of a porous cordierite ceramic article comprising: a mixture of (i) oxide sources of magnesia, alumina and silica in proportions effective to yield a ceramic article incorporating a predominant cordierite (Mg 2 Al 4 Si 5 O 18 ) crystal phase upon firing, (ii) one or more binders and lubricants, and (iii) a pore former in a proportion effective to develop a porosity of at least 50% by volume in the porous cordierite ceramic upon firing, the oxide source of alumina including at least one alumina powder having a mean particle size in the range of 15-50 μm and a surface area of at least 100 m 2 /g, and the pore former being present in amount less than 80% by weight calculated as a super-addition to the batch.