Nonwoven fabric having improved air permeability and manufacturing method thereof

Abstract

A nonwoven fabric having improved air permeability and manufacturing method thereof are presented. The nonwoven fabric has improved air permeability and is formed with long fiber nonwoven fabric of single or multi layer, wherein the long fiber nonwoven fabric is produced by spinning polytrimethylene terephthalate having viscosity of 0.8 to 1.2 and polyethylene terephthalate having viscosity of 0.6 to 0.8 to sheath/core shape with using each spinneret pack which can spin filaments having different denier from each other and arranged in parallel with each other, and then heat pressing with free-embossing or embossing pattern to bind the filaments. The nonwoven fabric has excellent air permeability, softness and resistance, which are required for nonwoven fabric sheets used for various purposes as well as their economical production.

What is claimed is: 
     
         1 . The nonwoven fabric having improved air permeability which is formed with long fiber nonwoven fabric of single or multi layer, wherein the long fiber nonwoven fabric is produced by spinning polytrimethylene terephthalate having viscosity of 0.8 to 1.2 and polyethylene terephthalate having viscosity of 0.6 to 0.8 to sheath/core shape with using each spinneret pack which can spin filaments having different denier each other and is arranged in parallel with each other, and then heat pressing with free-embossing or embossing pattern to bind the filaments. 
     
     
         2 . The nonwoven fabric of  claim 1 , wherein the component ratio of polytrimethylene terephthalate and polyethylene terephthalate constituting the said nonwoven fabric is polytrimethylene terephthalate of 10 to 50% by weight with respect to total weight. 
     
     
         3 . The nonwoven fabric of  claim 1 , wherein a basic weight of the said nonwoven fabric is 40 to 100 g/m 2 . 
     
     
         4 . The nonwoven fabric of  claim 1 , wherein the denier of filament consisting of the said nonwoven fabric is at least 2 to maximum 12 deniers. 
     
     
         5 . The nonwoven fabric of  claim 1 , wherein the air permeability of the said nonwoven fabric is above 200 ccs. 
     
     
         6 . The method for producing nonwoven fabric having improved air permeability, the method comprising the steps of:
 drying polyester having intrinsic viscosity of 0.6 to 0.8 and melting point of 260° C. and polytrimethylene terephthalate having viscosity of intrinsic viscosity of 0.8 to 1.2 and melting point of 225° C. in each dryer to moisture contents of below 100 ppm, and crystallizing and then providing it with an extruder;   spinning to sheath/core shape with using each spinneret pack which can spin filaments having different denier each other and is arranged in parallel with each other, wherein a filament is formed such that the spun polytrimethylene terephthalate is to 10-50% by weight with respect to total weight;   cooling the filament with cooled air, and consolidating it to prevent welding among the filament;   elongating and dispersing the filament by crashing it to an impinging plate with certain velocity and angle to form a web;   stacking the prepared filament uniformly on the moving conveyer belt successively to form a web by using a suction device at below; and   thermally bonding the said stacked filament web by using the calendar which has the upper roll set at temperature of 180-210° C. and the lower roll set at temperature of 188-208° C., and nip pressure of 30-100 kg/cm, and whose bonding rate is 10-30%.