Method for manufacturing and device for manufacturing ultrafine fiber nonwoven fabric

Abstract

A spinning die for producing ultrafine fiber nonwoven fabric is made miniaturized and its productivity thereof is enhanced. The spinning die has a substantial cuboid shape and a plurality of nozzle holes is disposed in a longitudinal direction. A slit for jetting hot air is disposed only in one side of the nozzle holes. Thermoplastic polymer is melt blown from the nozzle of the spinning die to obtain ultrafine fibers. Hot air is jetted from the slit disposed at only one side of the nozzle holes. The result is that the ultrafine fibers melt blown in a direction inclined with respect to an axis direction of the nozzle. The blown ultrafine fibers are accumulated by sucking to downward to obtain ultrafine fiber nonwoven fabric.

What is claimed is: 
     
         1 . A method for producing ultrafine fiber nonwoven fabric, comprising:
 a step of melt blowing thermoplastic polymer from a plurality of nozzle holes which are disposed in a longitudinal direction at a longitudinal lower end of a spinning die having a substantial cuboid shape to obtain ultrafine fibers,   a step of jetting out hot air from a slit disposed in only one side of the nozzle holes to blow the ultrafine fibers at an angle inclining with respect to the direction of an axial line of the nozzles, and   a step of accumulating the blown ultrafine fibers which are sucked downward from the spinning die to form the ultrafine fiber nonwoven fabric.   
     
     
         2 . The method for producing ultrafine fiber nonwoven fabric according to  claim 1 , wherein the slit is provided in either a right side or a left side of a line of the nozzle holes. 
     
     
         3 . The method for producing ultrafine fiber nonwoven fabric according to  claim 1 , wherein the ultrafine fibers are blown with hot air at an angle inclining  30 ° to  60 ° with respect to the axis line of the nozzles. 
     
     
         4 . An apparatus for producing ultrafine fiber nonwoven fabric, comprising a plurality of nozzle holes disposed in a longitudinal direction at a longitudinal lower end of a spinning die having a substantial cuboid shape, and a slit for jetting hot air disposed in only one side of a line of the nozzle holes. 
     
     
         5 . The apparatus for producing ultrafine fiber nonwoven fabric according to  claim 5 , wherein the slit is provided in only a right side of a line of the nozzle holes. 
     
     
         6 . The apparatus for producing ultrafine fiber nonwoven fabric according to  claim 5 , wherein the slit is provided in only a left side of a line of the nozzle holes. 
     
     
         7 . A combined apparatus for producing ultrafine fiber nonwoven fabric is disposing at least two of the apparatus according to  claim 5  in parallel. 
     
     
         8 . A combined apparatus for producing ultrafine fiber nonwoven fabric is disposing at least two of the apparatus according to  claim 6  in parallel. 
     
     
         9 . A combined apparatus for producing ultrafine fiber nonwoven fabric of  claim 4 , further comprising a first apparatus in which the slit is provided in only a right side of a line of the nozzle holes and a second apparatus in which the slit is provided in only a left side of a line of the nozzle holes. 
     
     
         10 . The apparatus of producing ultrafine fiber nonwoven fabric according to  claim 4 , wherein the hot air from the slit is jetted at an angle inclining  30 ° to  60 ° with respect to the axis direction of the nozzles.