| 摘要 |
PURPOSE: To provide a nonwoven fabric and filter medium provided with excellent foldability and high rigidity, and a producing method. CONSTITUTION: In the nonwoven fabric, at least 50% of total number of the fiber is a fiber bundle made by joining a plurality of a single fiber composed of a thermoplastic synthetic resin into a bundle and the fiber bundle is substantially oriented in one direction. The filter medium is made by combining the nonwoven fabric with an air permeable fiber sheet. In the producing method, the thermoplastic synthetic resin is jetted at 0.5g/hole.min discharge rate from a mouth ring having a spinning hole group oriented in <=1mm hole pitch to a collecting drum, arranged by offsetting the center of revolution from the vertical direction under the mouth ring, and the thermoplastic resin is collected on the collecting drum with the center line of melt blow fiber flow inclined at 10-30 deg. from the vertical direction under the mouth ring and at 5-20 deg. from the tangent line on the collecting drum at a point that the center line intersects the collecting drum. |
