Low leachable fibers and fiber structure

Abstract

A fiber including olefin-based resin, wherein temperatures of the olefin-based resin losing five percent by weight and the fiber losing five percent by weight have a difference of 20 degrees Celsius or below according to thermogravimetric measurements. The fiber can reduce the leaching of impurities with low molecular weight by controlling the deterioration of olefin-based resin when heated during its spinning process.

1 . A fiber comprising olefin-based resin, wherein temperatures of the olefin-based resin losing five percent by weight and the fiber losing five percent by weight have a difference of 20 degrees Celsius or lower according to thermogravimetric measurements. 
     
     
         2 . The fiber of  claim 1 , wherein the olefin-based resin is cyclic olefin-based resin. 
     
     
         3 . The fiber of  claim 1 , wherein all or part of a surface of the fiber is the olefin-based resin. 
     
     
         4 . The fiber of  claim 3 , wherein the fiber is a core-in-sheath-type composite fiber, a sea-island-type composite fiber or a parallel-type composite fiber. 
     
     
         5 . A fiber structure made from the fiber of  claim 1 . 
     
     
         6 . The fiber structure of  claim 5 , wherein the fiber structure is a filter or a medical fiber structure.