| 摘要 |
A porous honeycomb structure includes: a plurality of partition walls containing cordierite as a main component and constituted of a porous ceramic having a porosity of 55 to 75% and an average pore diameter of 15 to 35 mum, wherein the partition walls have a pore distribution represented by the following condition formula (1): <?in-line-formulae description="In-line Formulae" end="lead"?>Lr>0.3xP/100+0.91, (1)<?in-line-formulae description="In-line Formulae" end="tail"?> "in the above condition formula (1), Lr means an average developed length ratio, and P means a porosity obtained from a total pore volume measured by a mercury press-in type porosimeter, assuming that a true specific gravity of cordierite is 2.52 g/cc." The porous honeycomb structure is capable of effectively achieving raising of a trapping efficiency of soot or the like, lowering of a pressure loss, improving a purifying performance by effective use of a catalyst, and lengthening a trapping time, and is additionally capable of improving a dissolved loss limit at the time of filter regeneration, and an isostatic strength. |
