Patent ID: 6270608
Filing Date: 2001-08-07
Classification: D04H,E04B,Y10T

Abstract:
A method of forming a fibrous sorbent media of thermoplastic fibers, comprising:air laying a mat of thermoplastic fibers having a mean fiber diameter between about 0.5 microns and about 25 microns; the mat having a weight between about 2 ounces/yd.sup.2 and about 25 ounces/yd.sup.2 and a thickness of at least 1/20 of an inch; and the mat having first and second major surfaces;melting the thermoplastic fibers at and immediately adjacent the first and second major surfaces of the mat to form thermoplastic melt layers on the first and second major surfaces of the mat; subsequently cooling the thermoplastic melt layers to form liquid permeable, integral thermoplastic skins on the first and second major surf aces of the mat and a fibrous layer intermediate the thermoplastic skins; andsubsequent to the formation of the integral thermoplastic skins on the first and second major surfaces of the mat, penetrating the first major surface of the mat with unheated pins at spaced apart locations to point bond the thermoplastic fibers of the mat together to increase the integrity of the mat by heating the thermoplastic fibers at the spaced apart locations solely through the application of pressure to the thermoplastic fibers at the spaced apart locations.