Acrylic shrinkable fiber and method for production thereof

Abstract

An object of the present invention is to provide a dyeable acrylic shrinkable fiber that only slightly shrinks when dyed and has a high shrinkage percentage even after dyeing. By spinning an incompatible spinning solution, the above object can be achieved, and a dyeable acrylic shrinkable fiber that only slightly shrinks when dyed and has a high shrinkage percentage even after dyeing can be provided.

1 . A dyeable acrylic shrinkable fiber produced from a spinning solution comprising a polymer composition in which 50 to 99 parts by weight of a polymer (A) comprising 40 to 80 wt % of acrylonitrile, 20 to 60 wt % of a halogen-containing monomer and 0 to 5 wt % of a sulfonic acid-containing monomer is mixed with 1 to 50 parts by weight of a polymer (B) comprising 5 to 70 wt % of acrylonitrile, 20 to 94 wt % of other copolymerizable monomer and 1 to 40 wt % of a sulfonic acid-containing monomer, wherein the polymer (A) and the polymer (B) are incompatible with each other.  
   
   
       2 . The acrylic shrinkable fiber according to  claim 1 , wherein the total content of the sulfonic acid group-containing monomers in the polymers (A) and (B) is 0.1 to 10 parts by weight based on the total monomer content in the polymers (A) and (B).  
   
   
       3 . The acrylic shrinkable fiber according to  claim 1  or  2 , wherein the other copolymerizable monomer in the polymer (B) is an acrylic acid ester.  
   
   
       4 . The acrylic shrinkable fiber according to claims  1  or  2 , wherein the spinning solution is phase separated into particles having a particle size of 0.1 to 30 μm.  
   
   
       5 . The acrylic shrinkable fiber according to claims  1  or  2 , having a dyeing shrinkage percentage at 80° C. or less of 10% or less.  
   
   
       6 . The acrylic shrinkable fiber according to claims  1  or  2 , having a shrinkage percentage of 20% or more when dyed at 80° C. or less and then treated with dry heat at 130° C. for five minutes.  
   
   
       7 . The acrylic shrinkable fiber according to claims  1  or  2 , having a relative saturation value when dyed at 60° C. or more of 0.1 or more and a relative saturation value at 70° C. or more of 0.8 or more.  
   
   
       8 . A process for producing the acrylic shrinkable fiber according to claims  1  or  2 , comprising carrying out relaxation treatment at 1 to 20%.  
   
   
       9 . The acrylic shrinkable fiber according to  claim 3 , wherein the spinning solution is phase separated into particles having a particle size of 0.1 to 30 μm.  
   
   
       10 . The acrylic shrinkable fiber according to  claim 3 , having a dyeing shrinkage percentage at 80° C. or less of 10% or less.  
   
   
       11 . The acrylic shrinkable fiber according to  claim 4 , having a dyeing shrinkage percentage at 80° C. or less of 10% or less.  
   
   
       12 . The acrylic shrinkable fiber according to  claim 3 , having a shrinkage percentage of 20% or more when dyed at 80° C. or less and then treated with dry heat at 130° C. for five minutes.  
   
   
       13 . The acrylic shrinkable fiber according to  claim 4 , having a shrinkage percentage of 20% or more when dyed at 80° C. or less and then treated with dry heat at 130° C. for five minutes.  
   
   
       14 . The acrylic shrinkable fiber according to  claim 5 , having a shrinkage percentage of 20% or more when dyed at 80° C. or less and then treated with dry heat at 130° C. for five minutes.  
   
   
       15 . The acrylic shrinkable fiber according to  claim 3 , having a relative saturation value when dyed at 60° C. or more of 0.1 or more and a relative saturation value at 70° C. or more of 0.8 or more.  
   
   
       16 . The acrylic shrinkable fiber according to  claim 4 , having a relative saturation value when dyed at 60° C. or more of 0.1 or more and a relative saturation value at 70° C. or more of 0.8 or more.  
   
   
       17 . The acrylic shrinkable fiber according to  claim 5 , having a relative saturation value when dyed at 60° C. or more of 0.1 or more and a relative saturation value at 70° C. or more of 0.8 or more.  
   
   
       18 . The acrylic shrinkable fiber according to  claim 6 , having a relative saturation value when dyed at 60° C. or more of 0.1 or more and a relative saturation value at 70° C. or more of 0.8 or more.