A preparation method of self-crimping elastic combined filament yarns for knitting is disclosed, wherein the combined filament yarns are extruded from the same spinneret; a first fiber-forming polymer melt is divided into two ways, one is directly extruded after distribution; and the other is extruded after distribution by side-by-side composite spinning together with a second fiber-forming polymer melt; the first fiber-forming polymer and the second fiber-forming polymer are compatible or partially compatible; on the same spinneret, a ratio of the number of spinneret holes m for direct extrusion to the number of spinneret holes n for extrusion after distribution by side-by-side composite spinning is 1:(5-10); the self-crimping elastic combined filament yarns for knitting are prepared according to specific spinning processes, wherein the combined filament yarn mainly comprises a first fiber-forming polymer monofilament and a first/second fiber-forming polymer side-by-side composite monofilament; wherein the monofilament crimping directions are randomly distributed.

A preparation method of self-crimping elastic combined filament yarns for knitting is disclosed, wherein the combined filament yarns are extruded from the same spinneret; a first fiber-forming polymer melt is divided into two ways, one is directly extruded after distribution; and the other is extruded after distribution by side-by-side composite spinning together with a second fiber-forming polymer melt; the first fiber-forming polymer and the second fiber-forming polymer are compatible or partially compatible; on the same spinneret, a ratio of the number of spinneret holes m for direct extrusion to the number of spinneret holes n for extrusion after distribution by side-by-side composite spinning is 1:(5-10); the self-crimping elastic combined filament yarns for knitting are prepared according to specific spinning processes, wherein the combined filament yarn mainly comprises a first fiber-forming polymer monofilament and a first/second fiber-forming polymer side-by-side composite monofilament; wherein the monofilament crimping directions are randomly distributed.

A polymer body includes a first thermoplastic polymer, and a second thermoplastic polymer. The first thermoplastic polymer and the second thermoplastic polymer form a continuous solid structure. The first thermoplastic polymer forms an external supporting structure that at least partially envelops the second thermoplastic polymer. A first flow temperature of the first thermoplastic polymer is at least 10° C. higher than a second flow temperature of the second thermoplastic polymer. The first thermoplastic polymer may be removable by exposure to a selective solvent.

A polymer body includes a first thermoplastic polymer, and a second thermoplastic polymer. The first thermoplastic polymer and the second thermoplastic polymer form a continuous solid structure. The first thermoplastic polymer forms an external supporting structure that at least partially envelops the second thermoplastic polymer. A first flow temperature of the first thermoplastic polymer is at least 10° C. higher than a second flow temperature of the second thermoplastic polymer. The first thermoplastic polymer may be removable by exposure to a selective solvent.

A process for producing a thermoformable and bondable fabric in which the fabric is biodegradable and/or compostable. The process comprises extruding a polymeric blend to form a plurality of filaments, the filaments collectively comprising the fabric.

A process for producing a thermoformable and bondable fabric in which the fabric is biodegradable and/or compostable. The process comprises extruding a polymeric blend to form a plurality of filaments, the filaments collectively comprising the fabric.

A core-sheath conjugate fiber for artificial hair includes a core part and a sheath part. The core-sheath conjugate fiber for artificial hair is a colored fiber. The core part has a lightness L* of 10 or less in the CIE1976 color space and the sheath part has a lightness L* of 15 or more in the CIE1976 color space. With this configuration, the core-sheath conjugate fiber for artificial hair that has deep and natural colors similar to those of human hair and a good appearance, a hair ornament product including the same, and a method for producing the same are provided.

A core-sheath conjugate fiber for artificial hair includes a core part and a sheath part. The core-sheath conjugate fiber for artificial hair is a colored fiber. The core part has a lightness L* of 10 or less in the CIE1976 color space and the sheath part has a lightness L* of 15 or more in the CIE1976 color space. With this configuration, the core-sheath conjugate fiber for artificial hair that has deep and natural colors similar to those of human hair and a good appearance, a hair ornament product including the same, and a method for producing the same are provided.

An object of the present invention is to provide a process for producing fiberous board with which fiberous board exhibiting high bending strength and high stiffness at a wide range of heating temperatures and a wide range of compressing and heating times. In the present invention, fiberous board having an initial flexural modulus of at least 300 MPa in three point bending test is obtained by forming a web by correcting sheath-core composite fibers of which a core component is formed from a copolymer of ethylene glycol and terephthalic acid and the sheath component is formed from ethylene glycol, adipic acid, terephthalic acid, isophthalic acid; and/or diethylene glycol. The web is then compressed in a direction of thickness and heated, so that the sheath component softens and melts and the sheath-core composite fibers are melt bonded together and molded into a flat plate shape.

An object of the present invention is to provide a process for producing fiberous board with which fiberous board exhibiting high bending strength and high stiffness at a wide range of heating temperatures and a wide range of compressing and heating times. In the present invention, fiberous board having an initial flexural modulus of at least 300 MPa in three point bending test is obtained by forming a web by correcting sheath-core composite fibers of which a core component is formed from a copolymer of ethylene glycol and terephthalic acid and the sheath component is formed from ethylene glycol, adipic acid, terephthalic acid, isophthalic acid; and/or diethylene glycol. The web is then compressed in a direction of thickness and heated, so that the sheath component softens and melts and the sheath-core composite fibers are melt bonded together and molded into a flat plate shape.