Nonwoven sheet, method for making the same, and composite sheet incorporating it.

摘要

A nonwoven sheet is provided having lengthwise and transverse directions, said sheet being composed mainly of fine fibers which are individually distributed substantially throughout the sheet and mainly oriented in the lengthwise direction. The sheet also includes yarn-like fiber bundles of fine fibers which are also oriented in the lengthwise direction of the sheet. The yarn-like fiber bundles outnumber the fine fibers on one surface of the sheet material and the fine fibers outnumber the yarn-like fiber bundles on the other surface of the sheet material. It is made by a method in which a melted thermoplastic polymer is ejected from a spinneret with ejecting currents and thereafter it is impinged at a surface of a collecting member thereby forming a web characterized by the steps of arranging a melt blowing spinneret in such a way that the ejecting direction of the melted polymer and the current from the spinneret are inclined at an angle with respect to the tangential line of the surface of the collecting member thereby collecting said polymer into a web by producing a ejecting current which is forced to flow in one direction along the surface of the collecting member.