Patent attributes
A major object of the invention is to provide a thermoadhesive conjugate fiber with low heat shrinkability and high adhesion having low orientation and high elongation and having extremely satisfactory card-passing properties. The object of the invention can be achieved by a thermoadhesive conjugate fiber made of a fiber forming resin component and a crystalline thermoplastic resin having a melting point of at least 20° C. lower than that of the fiber forming resin component and having a breaking elongation of from 60 to 600%, a dry heat shrinkage percentage at 120° C. of from −10.0 to 5.0%, and more preferably a percentage of crimp/number of crimps of 0.8 or more; and a manufacturing method of a thermoadhesive conjugate fiber, which includes drawing an undrawn yarn of a conjugate fiber taken up at a spinning rate of from 150 to 1,800 m/min in a low draw ratio of from 0.5 to 1.3 times at a temperature higher than both a glass transition temperature of a major crystalline thermoplastic resin of the thermo-adhesive resin component and a glass transition temperature of the fiber forming resin component and simultaneously subjecting to a fixed-length heat treatment and subsequently subjecting to a heat treatment under no tension at a temperature of at least 5° C. higher than the temperature of the fixed-length heat treatment.
