Brush fiber, brush using brush fiber, and method for manufacturing brush fiber

Abstract

A brush fiber and a method for manufacturing the brush fiber are provided. The brush fiber includes a fibrous core portion, a covering portion provided on a surface of the core portion. A leading end portion of the core portion has a tapered shape, and the covering portion is made of conductive material. The conductive material is a sulfide of at least one type of metal selected from the group consisting of Cu, Ag, and Pd.

1 . A brush fiber, comprising:
 a fibrous core portion;   a covering portion provided on a surface of said core portion, wherein   a leading end portion of said core portion has a tapered shape, and said covering portion is made of conductive material.   
     
     
         2 . The brush fiber according to  claim 1 , wherein said core portion is made of one type of synthetic fiber selected from the group consisting of a polyester synthetic fiber, an acrylic synthetic fiber, and a polyamide synthetic fiber. 
     
     
         3 . The brush fiber according to  claim 1 , wherein said conductive material is made of a sulfide of at least one type of metal selected from the group consisting of Cu, Ag, and Pd or plated metal of at least one type of metal selected from the group consisting of Cu, Ag, and Ni. 
     
     
         4 . The brush fiber according to  claim 1 , wherein said core portion is made of polybutylene terephthalate, and said conductive material is made of a sulfide of Cu. 
     
     
         5 . The brush fiber according to  claim 1 , wherein a surface electricity resistance value of said brush fiber is equal to or greater than 10 −1  Ωcm and equal to or less than 10 9  Ωcm. 
     
     
         6 . A brush using the brush fiber according to  claim 1 . 
     
     
         7 . The brush according to  claim 6 , wherein equal to or greater than 1 volume % of a fiber bundle constituting said brush is said brush fiber. 
     
     
         8 . A method for manufacturing a brush fiber, comprising the steps of:
 immersing a leading end portion of a fibrous core portion in an alkaline solution;   washing said core portion after immersing; and   forming a conductive portion made of conductive material on a surface of said core portion after washing.