Laminated nonwoven fabric and method of manufacturing same

A method of manufacturing a laminated nonwoven fabric comprising the steps of:

• spinning composite continuous fibers from a low-melting point resin and a high melting point resin so that at least a portion of the fiber surface is formed by the low-melting point resin, the difference in melting point between the low melting point resin and the high melting point resin being at least 10° C., and forming a spun bonded web by a composite spun bonding method;
• or heating the resultant fiber web at a temperature not lower than a thermal fusion temperature thereby to form a nonwoven fabric in which the fibers are thermally fused;
• spinning composite meltblown extra-fine-fibers having an average fiber diameter of 10 μm or less, and comprising a low-melting point resin and a high melting point resin, the difference in melting point between the low melting point resin and the high melting point resin is at least 10° C., in such a fashion that the low-melting point resin forms at least a portion of the fiber surface, and forming a composite extra-fine-fiber web which does not include thermally fused portions by self-heating at the time of spinning, or forming a nonwoven fabric which includes portions thermally fused by self-heating at the time of spinning by a composite melt-blowing method;
• or forming a composite extra-fine-fiber nonwoven fabric in which the fibers are thermally fused by heating the spun fiber web or the nonwoven fabric which includes thermally self-fused portions at a temperature not lower than a thermal fusion temperature;
• laminating the spun bonded web or the thermally fused nonwoven fabric, and the composite melt-blown extra-fine-fiber web or a composite melt-blown extra-fine-fiber thermally-fused nonwoven fabric;
• and
• heating the resultant laminate at a temperature not lower than the temperature at which the two layers become thermally fused.