Ultrafine composite fiber, ultrafine fiber, method for manufacturing same, and fiber structure

Abstract

An ultrafine composite fiber of the present invention is obtained by heating and melting a composite-resin-formed product in front of a supply-side electrode and/or in a space between electrodes and extending the composite-resin-formed product by electrospinning, wherein the composite-resin-formed product is a solid-state composite-resin-formed product having two or more phases and including a resin that has a volume specific resistance of 10 15 Ω·cm or less, and that is exposed on 30% or more of a surface of the composite-resin-formed product. With this, an ultrafine composite synthetic fiber and an ultrafine synthetic fiber can be obtained by electrospinning, without a solvent being mixed in a supply resin, and further, a method for manufacturing an ultrafine composite fiber, as well as a fiber structure containing an ultrafine composite fiber, are provided.

1 . An ultrafine composite fiber obtained by heating and melting a composite-resin-formed product in front of a supply-side electrode and/or in a space between the supply-side electrode and a collection-side electrode and extending the composite-resin-formed product by electrospinning,
 wherein the composite-resin-formed product is a solid-state composite-resin-formed product having two or more phases and including a resin that has a volume specific resistance of 10 15  Ω·cm or less and that is exposed on 30% or more of a surface of the composite-resin-formed product, and   fiber components composing the ultrafine composite fiber are in a phase separation state.   
     
     
         2 . The ultrafine composite fiber according to  claim 1 , containing no solvent therein. 
     
     
         3 . The ultrafine composite fiber according to  claim 1 , wherein the composite-resin-formed product is a fiber having a phase structure of a sea-island type, a splittable type, or a core-sheath type. 
     
     
         4 . The ultrafine composite fiber according to  claim 1 , wherein the composite-resin-formed product is a monofilament, a multifilament composed of a plurality of monofilaments bundled, or a tow. 
     
     
         5 . The ultrafine composite fiber according to  claim 1 , wherein the resin component exposed on 30% or more of the surface of the composite-resin-formed product is at least one selected from ethylene-vinyl alcohol copolymers, polyesters, nylons, and polyurethanes, and a resin component of another phase is at least one selected from polyolefins, polyesters, nylons, and polylactic acids. 
     
     
         6 . An ultrafine fiber obtained by removing any of the components composing the ultrafine composite fiber according to  claim 1 . 
     
     
         7 . A method for manufacturing an ultrafine composite fiber, the method comprising the steps of:
 supplying a composite-resin-formed product to a supply-side electrode, wherein the composite-resin-formed product is a solid-state composite-resin-formed product having two or more phases and including a resin that has a volume specific resistance of 10 15  Ω·cm or less and that is exposed on 30% or more of a surface of the composite-resin-formed product;   heating and melting the composite-resin-formed product in front of the supply-side electrode and/or in a space between the supply-side electrode and a collection-side electrode; and   extending the molten composite-resin-formed product by electrospinning.   
     
     
         8 . The method for manufacturing an ultrafine composite fiber according to  claim 7 , wherein a heating-extending region is provided between the collection electrode and a position where the composite-resin-formed product is heated and molten. 
     
     
         9 . A fiber structure obtained by heating and melting a composite-resin-formed product in front of a supply-side electrode and/or in a space between the supply-side electrode and a collection-side electrode, and extending the composite-resin-formed product by electrospinning,
 wherein the composite-resin-formed product is a solid-state composite-resin-formed product having two or more phases and including a resin that has a volume specific resistance of 10 15  Ω·cm or less and that is exposed on 30% or more of a surface of the composite-resin-formed product, and   fiber components composing the ultrafine composite fiber are in a phase separation state.