AIR FILTER MEDIUM, AIR FILTER PACK AND AIR FILTER UNIT USING THE SAME, AND MANUFACTURING METHOD FOR AIR FILTER MEDIUM

摘要

PURPOSE: To provide an air filter medium, an air filter pack and an air filter unit with a high performance in which a raising of pressure loss and a reduction degree of capturing efficiency at the time of laminating are inhibited. CONSTITUTION: This air filter medium is used for air purification and is provided with a porous film and a nonwoven fabric. The porous film comprises a polytetrafluoroethylene and the nonwoven fabric is laminated on at least one surface of the porous film. An apparent density of the nonwoven fabric on at least one surface satisfies the following formula: apparent density (g/cm¬3)<1.5x(metsuke (g/m¬2)/1000)+0.11.