| 摘要 |
PROBLEM TO BE SOLVED: To manufacture a filter of high collecting properties while keeping the filter life by forming a filter layer of thermoplastic fibers composed by combining the fibers of a fiber forming component having irregular cross- sections with the fibers composed of a heat bonding component and heat fusion bonding the heat bonding component. SOLUTION: Fibers composed of a fiber forming component of high melting point resin such as polyolefin fibers or thermoplastic fibers are combined with fibers composed of a heat bonding component of resin of melting point lower than that of the fiber forming component. When combined fibers are heated up to the temperature in the middle of melting point of both fibers, the fibers of the heat bonding component are heat fusion bonded while keeping the irregular cross-sections as the original shape of the fiber forming component. A filter with its filter layer formed by the above process is provided with high collecting properties generated by the interruption on protruded parts of yarns having the irregular cross-sections and the sedimentation and adsorption into channels in addition to the physical filtration generated by the pore diameters among the fibers. |
