Inorganic nanofiber and method for manufacturing same

Abstract

Disclosed are an inorganic nanofiber characterized in that the average fiber diameter is 2 μm or less, the average fiber length is 200 μm or less, and the CV value of the fiber length is 0.7 or less; and a method of manufacturing the same. In the manufacturing method, an inorganic nanofiber sheet consisting of inorganic nanofibers having an average fiber diameter of 2 μm or less is formed by electrospinning, and then, the inorganic nanofiber sheet is pressed using a press machine and crushed so that the average fiber length becomes 200 μm or less, and the CV value of the fiber length becomes 0.7 or less.

1 . An inorganic nanofiber wherein an average fiber diameter is 2 μm or less, an average fiber length is 200 μm or less, and a CV value of a fiber length is 0.7 or less. 
     
     
         2 . The inorganic nanofiber according to  claim 1 , wherein a rate of change in fiber length (Lr) calculated from the following equation (1) is 30% or less:
     Lr =[( Lb−La )/ Lb]× 100  (1)
   
       wherein Lb is an average fiber length of the inorganic nanofiber, and La is an average fiber length after applying a pressure of 10 MPa to the inorganic nanofiber. 
     
     
         3 . A filler-dispersed organic resin composite, wherein the inorganic nanofiber according to  claim 1  is dispersed as an inorganic fibrous filler in an organic resin. 
     
     
         4 . The filler-dispersed organic resin composite according to  claim 3 , wherein the inorganic nanofiber is an alumina fiber, and a thermal conductivity is 3 W/m·K or more at a thickness of 0.3 mm. 
     
     
         5 . A method of manufacturing an inorganic nanofiber, comprising:
 forming an inorganic nanofiber sheet consisting of inorganic nanofibers having an average fiber diameter of 2 μm or less by electrospinning, and   pressing the inorganic nanofiber sheet using a press machine, and crushing it so that the average fiber length becomes 200 μm or less, and the CV value of the fiber length becomes 0.7 or less.   
     
     
         6 . A method of manufacturing an inorganic mixed nanofiber, comprising:
 mixing a first spinnable sol solution, which is a material for a first inorganic oxide, with a second spinnable sol solution or a metal salt solution, which is a material for a second inorganic oxide having a refractive index different from that of the first inorganic oxide, to prepare a spinnable mixed sol solution,   forming an inorganic mixed nanofiber sheet consisting of inorganic mixed nanofibers having an average fiber diameter of 2 μm or less from the spinnable mixed sol solution by electrospinning, and   pressing the inorganic mixed nanofiber sheet using a press machine, and crushing it so that the average fiber length becomes 200 μm or less, and the CV value of the fiber length becomes 0.7 or less,   wherein a potential hydrogen of the first spinnable sol solution is matched with that of the second spinnable sol solution or the metal salt solution, and the preparation of the spinnable mixed sol solution is carried out without being gelled.   
     
     
         7 . A filler-dispersed organic resin composite, wherein the inorganic nanofiber according to  claim 2  is dispersed as an inorganic fibrous filler in an organic resin. 
     
     
         8 . The filler-dispersed organic resin composite according to  claim 7 , wherein the inorganic nanofiber is an alumina fiber, and a thermal conductivity is 3 W/m·K or more at a thickness of 0.3 mm.