| abstract |
Sheath-core bicomponent fibers comprising a core of a low-cost, high strength, thermoplastic material, preferably polypropylene or polybutylene terephthalate, completely covered with a sheath formed of polyethylene terephthalate or a copolymer thereof are produced, preferably melt blown to an average diameter of 12 microns or less, and formed into a self-sustaining, three-dimensional, porous element having various applications, principally as an ink reservoir element for a marking or writing instrument, although the porous element may also find utility as a tobacco smoke filter. Other forms of the product have utility in diverse applications where its excellent capillary, absorption and filtering properties are advantageous. The resultant products retain or improve upon the desirable features and processing capabilities of conventional elements, but are substantially less expensive, requiring less high cost polyester for equivalent or better properties. |