PURPOSE: To provide a filter enhanced in dust collecting efficiency, capable of being washed and reutilized and reduced in life cycle cost by forming a filter member by combining two kinds of fibrous dielectric materials respectively having positively and negatively chargeable characteristics.
CONSTITUTION: A filter member 1 is constituted by combining a fibrous dielectric material (e.g. nylon 6, nylon 66) 2 having a positively chargeable characteristic and a fibrous dielectric material (e.g. Teflon, polyethylene) 3 having a negatively chargeable characteristic in a laminar state. Therefore, even when the filter member is washed using water and a detergent at the time of reutilization, the capacity of the filter member is restored if friction effect due to the passage of air is imparted after drying and the lowering of charge retentivity is not generated and dust collecting capacity is held over a long period of time. Since the fibrous dielectric materials 2, 3 having positively and negatively chargeable characteristics are rubbed with each other accompanied by an increast in the velocity of air passing through the filter member 1, charging effect is enhanced and dust collecting efficiency is enhanced still more.
HATTORI TAKAO
IWANAGA TAKAYOSHI
KUBOTA TORU
TOSHIBA AVE KK