Shrinkable fiber for porous molded body

Abstract

To provide an add-in material to be added to a porous molded body base, the add-in material being capable of developing a pore of appropriate size efficiently without degrading the formability and productivity of a porous molded body, particularly a porous fired body when producing the porous molded body. A shrinkable fiber composed of a thermoplastic resin and to be dispersed in a base of a porous molded body, particularly a porous fired body, wherein the shrinkable fiber has a fiber diameter of 10 to 40 μm, a fiber length of 1 to 20 mm, and a dry-heat shrinkage percentage of at least 8% when subjected to heat treatment at 80° C. for 5 minutes.

1 . A shrinkable fiber composed of a thermoplastic resin and to be dispersed in a porous molded body base, wherein the shrinkable fiber has a fiber diameter of 10 to 40 μm, a fiber length of 1 to 20 mm, and a dry-heat shrinkage percentage of at least 8% when subjected to heat treatment at 80° C. for 5 minutes. 
   
   
       2 . The shrinkable fiber according to  claim 1 , having a weight residual ratio of 10% or lower when heated at 500° C. 
   
   
       3 . The shrinkable fiber according to  claim 1 , which is a conjugate fiber obtained by conjugating a first component composed of a thermoplastic resin with a second component composed of a thermoplastic resin having a higher melting point than that of the first component, wherein the conjugate fiber has a weight residual ratio of 10% or lower when heated at 500° C. 
   
   
       4 . The shrinkable fiber according to  claim 3 , wherein the first component is a mixture of two or more types of thermoplastic resins, and at least one of the thermoplastic resins has a melting point of 100° C. or lower. 
   
   
       5 . The shrinkable fiber according to  claim 3 , wherein the centers of gravity of the conjugate components are different from each other in a fiber cross section. 
   
   
       6 . The shrinkable fiber according to  claim 1 , wherein a moisture percentage of a fiber assembly is 5 to 50%. 
   
   
       7 . The shrinkable fiber according to  claim 1 , having a standard moisture regain of 2% or less.