| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve durability against compression during long-term use, to maintain filtering pressure, to improve SS trapping ability and to prevent dropping of filaments. SOLUTION: This filter material 10 is produced in the following processes. A web prepared by entangling first filaments 11, second filaments 12 and third filaments 13 is formed into a cloth by a needle punching method. The first filaments 11 consist of a hot-melt conjugate fiber having 18 to 65 deniers comprising a polypropylene core and a polyethylene sheath. The second filaments 12 consist of a polypropylene fiber having 3 to 10 deniers. The third filaments consists of a hot-melt conjugate fiber having 1.5 to 6 deniers and comprising a polypropylene core and a polyethylene sheath. The obtd. cloth is heat treated without flattening the gigged state on both surfaces of the web. Thus, a cloth- like sheet having 200 to 800g/m<2> web weight and 2 to 8mm thickness is produced. The obtd. sheet is cut into squares having 3 to 50mm dimension.</p> |
