Filter element

Abstract

A filter element comprises an oil-impregnated filtering member, and a transmission preventing layer formed on a downstream side of the filtering member, for restricting transmission of at least the carbon dusts from the oil-impregnated filtering member. The filtering member may be formed like a ridge-like-folded structure. The transmission preventing layer may be formed of a coating layer having a resistance against a viscous oil that is impregnated in the filtering member. This coating layer may be formed uniformly as a whole or the thickness or the content of the coating layer may be increased partially. A ventilation shutting-off member (filling layer) may be formed as the transmission preventing layer in the root portion areas of the ridge portions. The transmission preventing layer may comprise a resistant component that is insoluble in the oil that is impregnated in the filtering member.

Dependencies are inferred from the claim text.