Method for producing treatment agent for synthetic fibers, treatment agent for synthetic fibers, synthetic fibers, and method for producing synthetic fibers

Abstract

The present invention addresses the problem of suitably suppressing fluffing during a spinning process. This method for producing a treatment agent for synthetic fibers, wherein the boron content in the nonvolatile content of the treatment agent for synthetic fibers as detected by ICP emission spectrometry is 200 ppm or less, comprises: an addition step wherein a (poly)oxyalkylene derivative is produced by adding an alkylene oxide to an alcohol in the presence of a catalyst that has a boron atom in each molecule; and a removal step wherein the catalyst is removed so that the boron content in the nonvolatile content of the treatment agent for synthetic fibers as detected by ICP emission spectrometry becomes 200 ppm or less.

1 . A method for producing a synthetic fiber treatment agent, the content of boron detected by ICP emission spectrometry from the nonvolatile content of the synthetic fiber treatment agent being not more than 200 ppm, the method comprising:
 an addition step of adding an alkylene oxide to an alcohol under presence of a catalyst having a boron atom in its molecule to prepare a (poly)oxyalkylene derivative, and   a removal step of removing the catalyst such that the content of boron detected by ICP emission spectrometry from the nonvolatile content of the synthetic fiber treatment agent is not more than 200 ppm.   
     
     
         2 . The method for producing a synthetic fiber treatment agent according to  claim 1 , wherein in the removal step, the catalyst is removed such that the content of boron detected by ICP emission spectrometry from the nonvolatile content of the synthetic fiber treatment agent is not more than 40 ppm. 
     
     
         3 . The method for producing a synthetic fiber treatment agent according to  claim 1 , wherein the (poly)oxyalkylene derivative includes a compound in which an alkylene oxide with 2 to 4 carbon atoms is added at a ratio of 1 to 30 moles in total to 1 mole of an alcohol. 
     
     
         4 . The method for producing a synthetic fiber treatment agent according to  claim 1 , wherein the alcohol has an alkyl chain with 10 to 18 carbon atoms in its molecule. 
     
     
         5 . The method for producing a synthetic fiber treatment agent according to  claim 1 , wherein the alcohol has an alkyl chain with 12 to 16 carbon atoms in its molecule. 
     
     
         6 . The method for producing a synthetic fiber treatment agent according to  claim 4 , wherein the alcohol is a monohydric aliphatic alcohol having a hydroxy group at a β-position of an alkyl chain. 
     
     
         7 . The method for producing a synthetic fiber treatment agent according to  claim 1 , further comprising a mixing step of mixing in a smoothing agent. 
     
     
         8 . The method for producing a synthetic fiber treatment agent according to  claim 7 , wherein the smoothing agent contains silicone. 
     
     
         9 . The method for producing a synthetic fiber treatment agent according to  claim 7 , wherein the smoothing agent contains an amino-modified silicone. 
     
     
         10 . The method for producing a synthetic fiber treatment agent according to  claim 7 , wherein in the mixing step, if the sum of the contents of the (poly)oxyalkylene derivative and the smoothing agent is taken as 100 parts by mass, the smoothing agent is mixed such that the content of the (poly)oxyalkylene derivative is 10 to 70 parts by mass and the content of the smoothing agent is 90 to 30 parts by mass. 
     
     
         11 . The method for producing a synthetic fiber treatment agent according to  claim 1 , wherein the synthetic fiber is a carbon fiber precursor. 
     
     
         12 . A synthetic fiber treatment agent comprising a smoothing agent and a (poly)oxyalkylene derivative,
 wherein the content of boron detected by ICP emission spectrometry from the nonvolatile content of the treatment agent is not less than 0.1 ppm and not more than 200 ppm.   
     
     
         13 . The synthetic fiber treatment agent according to  claim 12 , wherein the content of boron is not more than 40 ppm. 
     
     
         14 . The synthetic fiber treatment agent according to  claim 12 , wherein the (poly)oxyalkylene derivative includes a compound in which an alkylene oxide with 2 to 4 carbon atoms is added at a ratio of 1 to 30 moles in total to 1 mole of an alcohol. 
     
     
         15 . The synthetic fiber treatment agent according to  claim 14 , wherein the alcohol has an alkyl chain with 10 to 18 carbon atoms in its molecule. 
     
     
         16 . The synthetic fiber treatment agent according to  claim 14 , wherein the alcohol has an alkyl chain with 12 to 16 carbon atoms in its molecule. 
     
     
         17 . The synthetic fiber treatment agent according to  claim 15 , wherein the alcohol is a monohydric aliphatic alcohol having a hydroxy group at a β-position of an alkyl chain. 
     
     
         18 . The synthetic fiber treatment agent according to  claim 12 , wherein the smoothing agent contains an amino-modified silicone. 
     
     
         19 . The synthetic fiber treatment agent according to  claim 12 , wherein if the sum of the contents of the (poly)oxyalkylene derivative and the smoothing agent is taken as 100 parts by mass, content of the (poly)oxyalkylene derivative is 10 to 70 parts by mass and the content of the smoothing agent is 90 to 30 parts by mass. 
     
     
         20 . The synthetic fiber treatment agent according to  claim 12 , wherein the synthetic fiber is a carbon fiber precursor. 
     
     
         21 . A synthetic fiber to which the synthetic fiber treatment agent according to  claim 12  is adhered. 
     
     
         22 . A method for producing a synthetic fiber including adhering the synthetic fiber treatment agent according to  claim 12  to a fiber.