| 摘要 |
PROBLEM TO BE SOLVED: To provide a filter medium capable of easily and accurately creasing a filter medium sheet at a predetermined folding position to manufacture a pleat-like filter medium, and its creasing method. SOLUTION: Both sides of the predetermined folding position of the filter medium sheet F1 are pressed against a receiving tool 13 by press members 14 in order to form the filter medium sheet F1 made from a nonwoven fabric in a pleat shape. In this state, while heating the predetermined folding position, the filter medium sheet F1 is pressed in a shaping groove 13a of the receiving tool 13 by the creasing member 15 to crease the filter medium sheet F1 by the stretch of the nonwoven fabric. Thus, the thickness of the nonwoven fabric in a part of a crease F1a of the filter medium sheet F1 is formed so as to be thinner than that of the nonwoven fabric in other parts. COPYRIGHT: (C)2009,JPO&INPIT |
