ALUMINA FIBER AGGREGATE AND RETAINER FOR CATALYTIC CONVERTER COMPRISING THE SAME

摘要

An alumina fiber aggregate composed of alumina short fibers, characterized in that, when the fiber diameter of the alumina short fiber is x (mum), the percentage, in which a natural logarithm value lnx for x is less than ln3, is 2 % or less, in the logarithmic normal distribution of x, and also the value obtained by reducing the twofold of the standard error for said fiber diameters from the length weighted geometric mean diameter thereof is 6 mum or less; and a retainer for a catalytic converter comprising the alumina fiber aggregate. The alumina fiber aggregate is reduced in the scattering of fibers and thus is excellent from the view point of handlability and of working environment and sanitation, and also is suitable for use as a retainer for a catalytic converter and the like.