FILTER MEDIUM FOR AIR FILTER, MANUFACTURING METHOD THEREFOR, AND AIR FILTER USING THE SAME

摘要

<P>PROBLEM TO BE SOLVED: To provide an air filter medium and an air filter, which have low pressure drop, and have a high dust collection efficiency and a long service life, in a wide range of dust collection. Ž<P>SOLUTION: The air filter medium has laminated structure of at least two or more layers. The QF value (A) for electret nonwoven fabric disposed on the upstream side in the wind direction is higher than the QF value (B) for electret nonwoven fabric disposed downstream. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž