Modacrylic fibers for artificial hair include a modacrylic polymer; and a condensed phosphate. The modacrylic polymer includes 29.5 to 79.5% by mass of acrylonitrile, 20 to 70% by mass of vinyl chloride and/or vinylidene chloride, and 0.5 to 5% by mass of a sulfonic acid group containing vinyl monomer, with respect to a total mass of the modacrylic polymer. A content of the condensed phosphate in the modacrylic fibers is 0.05 to 0.57% by mass.

A fabric for arc-protective garments includes first yarns and second yarns different from the first yarns. The first yarns include first modacrylic fibers, and the first modacrylic fibers contain an infrared absorber in an amount of 2.5 wt % or more with respect to a total weight of the first modacrylic fibers. The weight of the infrared absorber per unit area in the fabric for arc-protective garments is 0.05 oz/yd.sup.2 or more. An arc-protective garment includes the fabric for arc-protective garments.

The present invention relates to a fiber for artificial hair having a hollow in a center of a fiber cross section. A ratio of an area of the hollow to an entire area of the fiber cross section is 5% to 50%. The fiber cross section has a flat multilobed shape, and the hollow has a first side and a second side that are inclined 70 to 110 degrees relative to a major axis of the fiber cross section. The present invention also relates to hair ornament products including the above fiber for artificial hair. Thus, the present invention provides a fiber for artificial hair having a favorable curl setting property when curling with a hair iron and a favorable combing property after curling with a hair iron, and hair ornament products including the same.

The present invention relates to a fiber for artificial hair having a hollow in a center of a fiber cross section. A ratio of an area of the hollow to an entire area of the fiber cross section is 5% to 50%. The fiber cross section has a flat multilobed shape, and the hollow has a first side and a second side that are inclined 70 to 110 degrees relative to a major axis of the fiber cross section. The present invention also relates to hair ornament products including the above fiber for artificial hair. Thus, the present invention provides a fiber for artificial hair having a favorable curl setting property when curling with a hair iron and a favorable combing property after curling with a hair iron, and hair ornament products including the same.

[Problem to be solved] A method for separating fibers that separates a modacrylic fiber, a polyvinyl chloride fiber and a polyester fiber and a method for producing fibers using these fibers obtained by the method for separating fibers are provided.

[Solution] A method for separating fibers contained in a fiber mixture from the fiber mixture, the method including a step of mixing the fiber mixture containing at least two selected from the group consisting of a modacrylic fiber, a polyvinyl chloride fiber and a polyester fiber, and a liquid mixture containing calcium chloride, a nonionic surfactant and water, and a method for producing a fiber, the method including a separation step of mixing a fiber mixture containing at least two selected from the group consisting of a modacrylic fiber, a polyvinyl chloride fiber and a polyester fiber, and a liquid mixture containing calcium chloride, a nonionic surfactant and water and a step of spinning a raw material containing a fiber separated in the separation step.

[Problem to be solved] A method for separating fibers that separates a modacrylic fiber, a polyvinyl chloride fiber and a polyester fiber and a method for producing fibers using these fibers obtained by the method for separating fibers are provided.

[Solution] A method for separating fibers contained in a fiber mixture from the fiber mixture, the method including a step of mixing the fiber mixture containing at least two selected from the group consisting of a modacrylic fiber, a polyvinyl chloride fiber and a polyester fiber, and a liquid mixture containing calcium chloride, a nonionic surfactant and water, and a method for producing a fiber, the method including a separation step of mixing a fiber mixture containing at least two selected from the group consisting of a modacrylic fiber, a polyvinyl chloride fiber and a polyester fiber, and a liquid mixture containing calcium chloride, a nonionic surfactant and water and a step of spinning a raw material containing a fiber separated in the separation step.

A process is described for the preparation of a homogeneous spinning solution for the production of acrylic or modacrylic fibers which comprises the following steps: i) preparation of an intimate mixture of a homopolymer or copolymer of acrylonitrile in powder form with a solid solvent in powder form, at a temperature lower than the melting point of the solid solvent; ii) gradually heating the intimate mixture of solids coming from step i) to a temperature ranging from 70 C. to 150 C. in a time ranging from 0.5 to 30 minutes, until the complete dissolution of the homopolymer or copolymer in the solvent and the formation of a homogeneous spinning solution. Said spinning solution is then fed to a storage tank or to the spinning line.

A process is described for the preparation of a homogeneous spinning solution for the production of acrylic or modacrylic fibers which comprises the following steps: i) preparation of an intimate mixture of a homopolymer or copolymer of acrylonitrile in powder form with a solid solvent in powder form, at a temperature lower than the melting point of the solid solvent; ii) gradually heating the intimate mixture of solids coming from step i) to a temperature ranging from 70 C. to 150 C. in a time ranging from 0.5 to 30 minutes, until the complete dissolution of the homopolymer or copolymer in the solvent and the formation of a homogeneous spinning solution. Said spinning solution is then fed to a storage tank or to the spinning line.

An acrylic fiber for artificial hair includes an acrylic copolymer obtained by copolymerizing acrylonitrile, vinyl chloride and/or vinylidene chloride, and a sulfonic acid group-containing vinyl monomer; and an organic solvent that can dissolve the acrylic copolymer, where the organic solvent is present in an amount of 0.1 to 3% by mass with respect to the total mass of the acrylic fiber for artificial hair. The acrylic fiber for artificial hair has an average surface roughness of 5900 ?m.sup.2 or less in an area of 40 ?m long and 80 ?m wide of the side surface of the fiber.

An acrylic fiber for artificial hair includes an acrylic copolymer obtained by copolymerizing acrylonitrile, vinyl chloride and/or vinylidene chloride, and a sulfonic acid group-containing vinyl monomer; and an organic solvent that can dissolve the acrylic copolymer, where the organic solvent is present in an amount of 0.1 to 3% by mass with respect to the total mass of the acrylic fiber for artificial hair. The acrylic fiber for artificial hair has an average surface roughness of 5900 ?m.sup.2 or less in an area of 40 ?m long and 80 ?m wide of the side surface of the fiber.