PURPOSE: To obtain a fiber capable of reversibly changing its color by water-absorption and desorption by using a sheath component consisting of an acrylonitrile copolymer containing hydrophobic group and a pigment and a core component consisting of an acrylonitrile copolymer containing hydrophilic group and a pigment and carrying out the conjugate spinning of the components in a coagulation bath.
CONSTITUTION: A solution (A) is produced by dissolving 10-30 pts.wt. of a copolymer composed of ≥50mol% of acrylonitrile and ≤50mol% of a comonomer having hydrophobic group and ≥0.3 pts.wt. of a pigment in a solvent and, separately, a solution (B) is produced by dissolving 15-30 pts.wt. of a copolymer composed of ≥80mol% of acrylonitrile and ≤20mol% of a comonomer containing hydrophilic group and 0.001-0.3 pts.wt. of a pigment different from that of the component A in a solvent. The solutions A and B are subjected to conjugate spinning in a coagulation bath in such a manner as to expose the component A on at least a part of the outer circumference of the spun fiber. The produced fiber is washed, drawn and dried to obtain the objective fiber having a layer containing open micro-voids on at least a part of the outer surface and a layer free from micro-void and having different color hue on the remaining part of the outer surface.
HAGURA SHIGEKI
MURAOKA TOSHIMI
ITO HAJIME
