| 摘要 |
PURPOSE:To provide a compact filter reduced in pressure loss and having high particle removing efficiency by creasing a filter material formed by laminating a nonwoven fabric wherein fibers are highly arranged in an MD direction, and a reticulated sheet are laminated in a CD direction to subject the same to pleating processing. CONSTITUTION:A filter material formed by laminating a nonwoven fabric wherein the ratio (MD/CD) of tensile strength in a longitudinal (MD) direction and that in a lateral (CD) direction is 6 or more, and fibers are highly arranged in the MD direction to a reticulated sheet is creased in the CD direction to be subjected to pleating processing. As a raw material of the nonwoven fabric, a synthetic fiber composed of polyethylene, polyester, polyamide, polyphenylene sulfide, polyimide or polyvinylidene fluoride, a regenerated fiber such as cellulose, a natural fiber such as cotton and an inorg. fiber composed of a metal, glass or ceramic are designated. By this method, the structural resistance of a filter is markedly reduced and particle removing efficiency can also be held to a high level. |
