Abstract: The present invention is intended to provide an organic resin non-crimped staple fiber that has notably few defects and that uniformly disperses in a dispersion medium, and that is preferred for use in wet-laid nonwoven fabrics or resin reinforcement in applications such as in industrial materials and daily commodities. The organic resin non-crimped staple fiber of the present invention has a fineness of 0.0001 to 0.6 decitex, a fiber length of 0.01 to 5.0 millimeters, a moisture content of 10 to 200 weight %, a cut-end coefficient of 1.00 to 1.40, and a coefficient of variation relative to fiber length (CV %) of 0.0 to 15.

Abstract: The present invention has an object to provide staple fibers suitable for manufacturing a wet-laid nonwoven fabric having excellent adhesive strength and heat resistance at a reduced environmental burden, a manufacturing method of the same, and a nonwoven fabric using the staple fibers. The object can be achieved by polyalkylene terephthalate or polyalkylene naphthalate staple fiber wet nonwoven fabric having excellent adhesive strength and heat resistance that are provided by blending and thermal-compression bonding of low oriented yarn and fully oriented yarn, wherein a specific ratio of biomass-derived carbon, fineness, fiber length, and a weight ratio between fully oriented staple fibers and low oriented staple fibers in the wet-laid nonwoven fabric are used to obtain a fine low oriented yarn having excellent binder performance and a fine fully oriented yarn having an unprecedented level of fineness.

Abstract: The present invention has an object to provide staple fibers suitable for manufacturing a wet-laid nonwoven fabric having excellent adhesive strength and heat resistance at a reduced environmental burden, a manufacturing method of the same, and a nonwoven fabric using the staple fibers. The object can be achieved by polyalkylene terephthalate or polyalkylene naphthalate staple fiber wet nonwoven fabric having excellent adhesive strength and heat resistance that are provided by blending and thermal-compression bonding of low oriented yarn and fully oriented yarn, wherein a specific ratio of biomass-derived carbon, fineness, fiber length, and a weight ratio between fully oriented staple fibers and low oriented staple fibers in the wet-laid nonwoven fabric are used to obtain a fine low oriented yarn having excellent binder performance and a fine fully oriented yarn having an unprecedented level of fineness.

Abstract: The present invention has an object to provide staple fibers suitable for manufacturing a wet-laid nonwoven fabric having excellent adhesive strength and heat resistance at a reduced environmental burden, a manufacturing method of the same, and a nonwoven fabric using the staple fibers. The object can be achieved by polyalkylene terephthalate or polyalkylene naphthalate staple fiber wet nonwoven fabric having excellent adhesive strength and heat resistance that are provided by blending and thermal-compression bonding of low oriented yarn and fully oriented yarn, wherein a specific ratio of biomass-derived carbon, fineness, fiber length, and a weight ratio between fully oriented staple fibers and low oriented staple fibers in the wet-laid nonwoven fabric are used to obtain a fine low oriented yarn having excellent binder performance and a fine fully oriented yarn having an unprecedented level of fineness.

Abstract: The present invention has an object to provide staple fibers suitable for manufacturing a wet-laid nonwoven fabric having excellent adhesive strength and heat resistance at a reduced environmental burden, a manufacturing method of the same, and a nonwoven fabric using the staple fibers. The object can be achieved by polyalkylene terephthalate or polyalkylene naphthalate staple fiber wet nonwoven fabric having excellent adhesive strength and heat resistance that are provided by blending and thermal-compression bonding of low oriented yarn and fully oriented yarn, wherein a specific ratio of biomass-derived carbon, fineness, fiber length, and a weight ratio between fully oriented staple fibers and low oriented staple fibers in the wet-laid nonwoven fabric are used to obtain a fine low oriented yarn having excellent binder performance and a fine fully oriented yarn having an unprecedented level of fineness.

Abstract: The method of producing an islands-in-sea type composite spun fiber having an island component diameter of 1 ?m or less according to the present invention comprises drawing (superdrawing) with a total draw ratio of from 5 to 100 an undrawn islands-in-sea type composite spun fiber having been prepared by spinning at a spinning speed of from 100 to 1,000 m/min, at temperatures higher than the glass transition points of both the polymer forming the sea component and the polymer forming the island components of the composite spun fiber.

Abstract: 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.

Abstract: An object of the invention is to provide a polyester based fiber for airlaid nonwoven fabrics enabling one to manufacture an airlaid nonwoven fabric which is extremely excellent in airlaid web formability, especially in spinning properties from a screen, is satisfactory in texture and is bulky. This object can be achieved by a manufacturing method of a polyester fiber for airlaid nonwoven fabrics made of, as a fiber forming resin component, a polyester having a fineness of not more than 10.0 dtex or a fiber length of 8.0 mm or more, having a number of crimp of 8.5 peaks/25 mm or more, a percentage of crimp/number of crimp ratio of not more than 0.65 and a crimp modulus of elasticity of 70% or more and containing 80% by mole or more of an alkylene terephthalate repeating unit in the whole of repeating units, which includes drawing an undrawn yarn taken up at a spinning rate of not more than 1,500 m/min in a low draw ratio of from 0.60 to 1.20 times at a temperature of at least 10° C.

Abstract: An essential object of the invention is to provide a low-modulus, self-extensible thermal-adhesive bicomponent fiber including polyethylene terephthalate as the fiber-forming resin component thereof and capable of producing a nonwoven fabric or a fiber structure that has a high adhesive strength and is bulky and well drapable. The object of the invention is attained by a self-extensible thermal-adhesive bicomponent fiber that includes a fiber-forming resin component and a thermal-adhesive resin component and is characterized in that the fiber-forming resin component includes polyethylene terephthalate, that the thermal-adhesive resin component includes a crystalline thermoplastic resin having a melting point lower by at least 20° C. than that of the fiber-forming resin component, and that its breaking elongation is from 130 to 600%, its 100% elongation tensile strength is from 0.3 to 1.0 cN/dtex and its 120° C. dry heat shrinkage is smaller than ?1.0%; and by a method for producing it.

Abstract: Synthetic staple fibers having good air opening property and useful for producing an air-laid nonwoven fabric having excellent quality, have a fiber length of 0.1 to 45 mm and a cross-sectional profile having 1 to 30 concavities, in which cross-sectional profile the ratio D/L, of a largest depth D of each concavity to a largest width L of the opening of the concavity, is in the range of from 0.1 to 0.5.

Abstract: Synthetic staple fibers having good air opening property and useful for producing an air-laid nonwoven fabric having excellent quality, have a fiber length of 0.1 to 45 mm and a cross-sectional profile having 1 to 30 concavities, in which cross-sectional profile the ratio D/L, of a largest depth D of each concavity to a largest width L of the opening of the concavity, is in the range of from 0.1 to 0.5.

Abstract: The method of producing an islands-in-sea type composite spun fiber having an island component diameter of 1 ?m or less according to the present invention comprises drawing (superdrawing) with a total draw ratio of from 5 to 100 an undrawn islands-in-sea type composite spun fiber having been prepared by spinning at a spinning speed of from 100 to 1,000 m/min, at temperatures higher than the glass transition points of both the polymer forming the sea component and the polymer forming the island components of the composite spun fiber.

Abstract: 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.

Abstract: Polyester staple fibers containing a polymeric blend of 0.5 to 15 mass % of a polyolefinic polymer with a matrix polyester polymer, 50% or more of the surface area of each fiber being formed by the polymeric blend, are useful for forming a nonwoven fabric with soft hand and a uniform texture by using various web-forming methods, for example, an air laid, wet laid or carding method.

Abstract: A nonwoven fabric having an enhanced bulkiness and uniformity is produced by forming a nonwoven fabric, by an air-laid method, from machine-crimped synthetic fibers having a thickness of 0.5 to 200 dtex and a length of 3 to 30 mm, each fiber being constituted from two portions disproportional in thermal shrinkability from each other and located on both respective sides with respect to an imaginary interface extending along the longitudinal axis of each fiber, to thereby exhibit a latent crimpability upon being heated to manifest three-dimensional crimps and each fiber having mechanical crimps at the number of crimps of 1 to 13 crimps/25 mm and a crimp ratio of 2 to 20%; and heat-treating the resultant air-laid nonwoven fabric to manifest the three dimensional crimps on each fiber in the fabric.

Abstract: Polyester staple fibers containing a polymeric blend of 0.5 to 15 mass % of a polyolefinic polymer with a matrix polyester polymer, 50% or more of the surface area of each fiber being formed by the polymeric blend, are useful for forming a nonwoven fabric with soft hand and a uniform texture by using various web-forming methods, for example, an air laid, wet laid or carding method.

Abstract: The machine-crimped synthetic fibers of the present invention have a thickness of 0.5 to 200 dtex, a fiber length of 3 to 20 mm and the number of crimps of 1 to 13 crimps/25 mm and a crimp percentage of 2 to 20%, each fiber having two portions disproportional in thermal shrinkage with each other and located in two sides of the fiber divided by an interface by which the fiber is divided along the longitudinal axis of the fiber into two side portions, to cause the fiber to have such a latent crimping property that when heat treated at 60 to 200° C., the two side portions of the fiber disproportionally shrink and the shrunk fiber exhibits three-dimensional crimps having the number of crimps of 15 to 80 crimp/25 mm and a crimp percentage of 25 to 90%. The fibers are produced by disproportionally cool-solidifying in fiber-forming procedure or by forming in an eccentric core-in-sheath type on side-by-side type composite fiber structure.

Abstract: Polyester-based heat-bonding conjugate staple fibers capable of giving a high grade fiber structure which has good dimensional stability and is hardly deformed, even when used under a high temperature atmosphere, comprises an amorphous polyester having a glass transition point of 50 to 100° C. and not having a crystal-melting point as a heat-bonding component and a polyalkylene terephthalate having a melting point of not less than 220° C. as a fiber-forming component, have characteristics comprising the number of crimps of 3 to 40 crimps/25 mm, a crimp percent of 3 to 40% and a web area shrinkage percent of not more than 20%. Herein, the web area shrinkage percent (%) is represented by the expression: (A0−A1)/A0×100, wherein a card web nonwoven fabric comprising 100% of the heat-bonding conjugate staple fibers and having an area of A0 and a basis weight of 30 g/m2 is left in a hot air dryer maintained at 150° C. for two minutes, and the area of the left nonwoven fabric is A1.

Abstract: A hydrophilic fiber which is a fiber having the ratio of the perimeter occupied by a polyolefin to the whole perimeter of the fiber cross section of 30% or above, the hydrophilic property of the fiber of 30 seconds or below and the retention of the hydrophilic property of the fiber with the lapse of time of 90% or above before and after treatment at a temperature of 40° C. and a relative humidity of 80% with the lapse of time of 30 days, with the proviso that the hydrophilic property of the fiber is measured by the following method: The interior of a pipe made of polymethyl methacrylate and having an inside diameter of 25 mm, an outside diameter of 30 mm and a pipe length of 25 mm is stuffed with 5.0 grams of fibers so as not to protrude the fibers. Said pipe is floated on 1,000 cc of softened water at 30° C. in a container having a caliber of 105 mm &phgr; and filled with the water, allowed to stand and once sunk to the bottom.