METHOD FOR PRODUCING FILTER MATERIAL FOR BAG FILTER, POLYTETRAFLUOROETHYLENE POROUS FILM TO BE USED THEREFOR, AND FILTER MATERIAL FOR BAG FILTER

摘要

PROBLEM TO BE SOLVED: To improve bending resistance or the like of a filter medium obtained by joining a polytetrafluoroethylene (PTFE) porous film and a glass woven fabric and to provide a filter medium for a bag filter with excellent heat resistance utilizing that of the glass woven fabric. SOLUTION: A PTFE porous film having 0.25 N or higher and 60% or higher as tensile strengths and elongations in the flow direction (MD direction; longitudinal direction) and the direction orthogonal to the former (TD direction; width direction), respectively, is used. This PTFE porous film is joined to a glass woven fabric by heat lamination to obtain the filter medium for a bag filter. This filter medium is excellent in bending resistance qualified by a back washing test to which conventional these kinds of filter media cannot stand. COPYRIGHT: (C)2009,JPO&INPIT