Method for producing light weight ultrafine fiber fabric

Abstract

A method for producing a ultrafine fiber includes spinning an island polymer and a sea polymer to a ultrafine fiber. The island polymer is an olefin polymer and the sea polymer has a different dissolving property from that of the island polymer. A method for producing a ultrafine fiber substrate, which includes obtaining a substrate from the ultrafine fiber from the above-mentioned method, dissolving and removing the sea polymer in the substrate to obtain the ultrafine fiber substrate.

What is claimed is:  
     
         1 . A method for producing a ultrafine fiber, comprising: 
 spinning an island polymer and a sea polymer into a ultrafine fiber, wherein said island polymer is an polyolefin polymer and said sea polymer has a different dissolving and removing property from that of said island polymer.    
     
     
         2 . A method according to  claim 1 , wherein said island polymer and sea polymer is spun in a weight ratio ranging from about 5:95 to about 95:5 by a mixed spinning method or a conjugated spinning method to said fiber.  
     
     
         3 . A method according to  claim 1 , wherein said island polymer is an polyolefin polymer having a density less than 1.0 g/cm 3  and a flexural modulus more than 9000 kg/cm 2 .  
     
     
         4 . A method according to  claim 1 , wherein said island polymer is selected from the group consisting of polypropylene, polyethylene, ethylene-propylene copolymer, polyethylene elastomer polymer, and polypropylene elastomer polymer.  
     
     
         5 . A method according to  claim 1 , wherein said sea polymer is an organic solvent-soluble polyolefin polymer selected from the group consisting of polystyrene, polyethylene, and ethylene-propylene copolymer.  
     
     
         6 . A method according to  claim 1 , wherein said sea polymer is an alkali-soluble polymer selected from the group consisting of sulfonic sodium containing polyethyleneterephthalate and derivatives thereof.  
     
     
         7 . A method according to  claim 1 , wherein said sea polymer further comprises at least one component selected from the group consisting of para-terephthalic acid, aliphatic dicarboxylic acid, aromatic dicarboxylic acid, aliphatic diol, aromatic diol, carboxylic acid and derivatives thereof.  
     
     
         8 . A method according to  claim 1 , wherein said sea polymer is a water-soluble polymer selected from the group consisting of polyvinyl alcohol, water-soluble polyester copolymer comprising isopropyl alcohol (IPA). terephthalic acid (TPA), acrylic acid (AA), sulfonic sodium salt (SIP), and polyethyleneglycol.  
     
     
         9 . A method for producing a ultrafine fiber substrate, comprising: 
 spinning an island polymer and a sea polymer into a ultrafine fiber, wherein said island polymer is an polyolefin polymer and said sea polymer has a different dissolving and removing property from that of said island polymer;    producing a substrate from said ultrafine fiber; and    removing said sea polymer from said substrate to obtain said ultrafine fiber substrate.    
     
     
         10 . A method according to  claim 9 , further comprising a step of immersing said substrate into a polymer prior to removing said sea polymer from said substrate.  
     
     
         11 . A method according to  claim 9 , further comprising a step of polishing a surface of said substrate surface after removing said sea polymer from said substrate.  
     
     
         12 . A method according to  claim 9 , wherein said substrate is needle punch nonwoven or water punch nonwoven, weaving, knitting.  
     
     
         13 . A method according to  claim 9 , wherein said island polymer is an polyolefin polymer having a density less than 1.0 g/cm 3  and a flexural modulus more than 9000 kg/cm 2 .  
     
     
         14 . A method according to  claim 9 , wherein said island polymer is selected from the group consisting of polypropylene, polyethylene, ethylene-propylene copolymer, polyethylene elastomer polymer, and polypropylene elastomer polymer.  
     
     
         15 . A method according to  claim 9 , wherein said sea polymer is an organic solvent-soluble polyolefin polymer selected from the group consisting of polystyrene, polyethylene, and ethylene-propylene copolymer.  
     
     
         16 . A method according to  claim 9 , wherein said sea polymer is an alkali-soluble polymer selected from the group consisting of sulfonic sodium containing polyethyleneterephthalate and derivatives thereof.  
     
     
         17 . A method according to  claim 16 , wherein said sea polymer further comprises at least one component selected from the group consisting of para-terephthalic acid, aliphatic dicarboxylic acid, aromatic dicarboxylic acid, aliphatic diol, aromatic diol, carboxylic acid and derivatives thereof.  
     
     
         18 . A method according to  claim 9 , wherein said sea polymer is a water-soluble polymer selected from the group consisting of polyvinyl alcohol, water-soluble polyester copolymer comprising isopropyl alcohol (IPA), terephthalic acid (TPA), acrylic acid (AA), sulfonic sodium salt (SIP), and polyethyleneglycol.  
     
     
         19 . A method according to  claim 9 , wherein said island polymer has a fineness from about 0.5 to 0.001 denier per filament after removing said sea polymer from said ultrafine fiber.  
     
     
         20 . A method according to  claim 9 , wherein said island polymer and sea polymer is spun in a weight ratio ranging from about 5:95 to about 95:5 by a mixed spinning method or a conjugated spinning method to said fiber.