Abstract: A substrate for artificial leather comprising a nonwoven fabric of bundles of microfine filaments. The substrate for artificial leather simultaneously satisfies the following requirements 1 to 4: (1) the bundle of microfine filaments comprises 8 to 70 microfine filaments having a cross-sectional shape of nearly circle; (2) the bundle of microfine filaments has a cross-sectional area of 170 to 700 ?m2 and a flatness of 4.0 or less; (3) on a cross section parallel to a thickness direction of the nonwoven fabric body, cross sections of the microfine fiber bundles exist in a density of 1500 to 3000/mm2; and (4) on a cross section parallel to a thickness direction of the nonwoven fabric body, gaps between the microfine fiber bundles have a size of 70 ?m or less. By satisfying the requirements, the substrate for artificial leather combines high level of sensuous qualities and high level of physical properties which have been considered to be mutually exclusive.

Abstract: A leather-like sheet containing a microfine long-fiber nonwoven fabric containing an entangled web structure made of bundles of microfine long fibers and an elastic polymer impregnated in the microfine long-fiber nonwoven fabric. The leather-like sheet has a machine direction/transverse direction ratio of breaking strength of 1/1 to 1.3/1, an elongation at break in each of the machine direction and the transverse direction of 80% or more, and a machine direction/transverse direction ratio of elongation at break of 1/1 to 1/1.5. The leather-like sheet has a natural dense feeling, a soft hand, a small difference of mechanical properties in the machine direction and the transverse direction, a moderate resistance to elongation and a durable recovery.

Abstract: Disclosed is a gas separation composite membrane comprising a polyamidoamine dendrimer (A) having a specific group, a vinyl alcohol-based polymer (B) containing 0.5 to 5 mol % of carboxyl groups, and a crosslinking agent (C) having an azetidinium group, wherein the mass ratio (A)/(C) of the polyamidoamine dendrimer (A) to the crosslinking agent (C) having an azetidinium group is 20/80 to 65/35, and the mass ratio (B)/(C) of the vinyl alcohol-based polymer (B) to the crosslinking agent (C) having an azetidinium group is 20/80 to 80/20. Thus, a gas separation composite membrane capable of separating a specific type of gas from a mixed gas containing water vapor is provided.

Abstract: Disclosed is a gas separation composite membrane comprising a polyamidoamine dendrimer (A) having a specific group, a vinyl alcohol-based polymer (B) containing 0.5 to 5 mol % of carboxyl groups, and a crosslinking agent (C) having an azetidinium group, wherein the mass ratio (A)/(C) of the polyamidoamine dendrimer (A) to the crosslinking agent (C) having an azetidinium group is 20/80 to 65/35, and the mass ratio (B)/(C) of the vinyl alcohol-based polymer (B) to the crosslinking agent (C) having an azetidinium group is 20/80 to 80/20. Thus, a gas separation composite membrane capable of separating a specific type of gas from a mixed gas containing water vapor is provided.

Abstract: A method of producing an entangled sheet of microfine long fibers using long fibers for forming microfine fibers. The method includes a step of forming a long-fiber web made of long fibers for forming microfine fibers, at least one component of the long fibers being a water-soluble, thermoplastic polyvinyl alcohol resin; a step of entangling the long-fiber web to form a long-fiber entangled sheet; a step of shrinking the long-fiber entangled sheet to form a long-fiber shrunk sheet; and a step of converting the long fibers for forming microfine fibers in the long-fiber shrunk sheet to microfine long fibers, thereby producing the entangled sheet of microfine long fibers. The step of entangling is conducted so as to allow the long-fiber entangled sheet to have an interlaminar peel strength of 2 kg/2.5 cm or more. The step of shrinking is conducted so as to shrink in an areal shrinkage of 35% or more.

Abstract: A substrate for artificial leather comprising a nonwoven fabric of bundles of microfine filaments. The substrate for artificial leather simultaneously satisfies the following requirements 1 to 4: (1) the bundle of microfine filaments comprises 8 to 70 microfine filaments having a cross-sectional shape of nearly circle; (2) the bundle of microfine filaments has a cross-sectional area of 170 to 700 ?m2 and a flatness of 4.0 or less; (3) on a cross section parallel to a thickness direction of the nonwoven fabric body, cross sections of the microfine fiber bundles exist in a density of 1500 to 3000/mm2; and (4) on a cross section parallel to a thickness direction of the nonwoven fabric body, gaps between the microfine fiber bundles have a size of 70 ?m or less. By satisfying the requirements, the substrate for artificial leather combines high level of sensuous qualities and high level of physical properties which have been considered to be mutually exclusive.

Abstract: The leather-like sheet substrate of the present invention comprises a fiber-entangled nonwoven fabric that comprises a microfine fiber bundle (A) and a microfine fiber bundle (B) in a blending ratio (A)/(B) of 30/70 to 70/30 by mass and a polymeric elastomer contained in the fiber-entangled nonwoven fabric. The microfine fiber bundle (A) comprises 10 to 100 microfine fibers each of which has a single fiber fineness of 0.5 dtex or less and which are made of an elastic polymer having a JIS A hardness of 90 to 97. The microfine fiber bundle (B) comprises a microfine fiber which has a single fiber fineness of 0.5 dtex or less and which is made of a non-elastic polymer. Because of its excellent stretchability in both the machine and transverse directions and drapeability, the leather-like sheet substrate is particularly suitable as the material for clothing.

Abstract: A leather-like sheet comprising a microfine long-fiber nonwoven fabric comprising an entangled web structure made of bundles of microfine long fibers and an elastic polymer impregnated in the microfine long-fiber nonwoven fabric. The leather-like sheet has the following features: (1) each of the bundles of microfine long fibers comprises 5 to 70 microfine long fibers having an average single fiber fineness of 0.5 dtex or less; (2) the bundles of microfine long fibers have an average fineness of 3 dtex or less; (3) the entangle web structure comprises superposed webs each comprising the bundles of microfine long fibers; (4) a ratio of the microfine long fibers and the elastic polymer is 70/30 to 40/60 by mass; (5) the elastic polymer is substantially continuous; and (6) a machine direction/transverse direction ratio of breaking strength is 1/1 to 1.

Abstract: A method of producing an entangled sheet of microfine long fibers using long fibers for forming microfine fibers. The method includes a step of forming a long-fiber web made of long fibers for forming microfine fibers, at least one component of the long fibers being a water-soluble, thermoplastic polyvinyl alcohol resin; a step of entangling the long-fiber web to form a long-fiber entangled sheet; a step of shrinking the long-fiber entangled sheet to form a long-fiber shrunk sheet; and a step of converting the long fibers for forming microfine fibers in the long-fiber shrunk sheet to microfine long fibers, thereby producing the entangled sheet of microfine long fibers. The step of entangling is conducted so as to allow the long-fiber entangled sheet to have an interlaminar peel strength of 2 kg/2.5 cm or more. The step of shrinking is conducted so as to shrink in an areal shrinkage of 35% or more.

Abstract: The flame-retardant leather-like sheet substrate of the present invention comprises a layer (A) that is made of an entangled nonwoven fabric comprising a polyester superfine fiber (a) of a single fiber fineness of 0.5 dtex or less containing no flame-retardant component and a flame-retardant polyester superfine fiber (b) of a single fiber fineness of 0.5 dtex or less containing a flame-retardant component in a ratio, (a)/(b), of 100/0 to 40/60 by mass, and a layer (B) that is made of an entangled nonwoven fabric comprising the polyester superfine fiber (a) and the flame-retardant polyester superfine fiber (b) in a ratio, (a)/(b), of 70/30 to 0/100 by mass. The entangled nonwoven fabrics of the layers (A) and (B) are impregnated with an elastomeric polymer (c) containing a flame-retardant component. The ratio of the polyester superfine fiber (a) and the flame-retardant polyester superfine fiber (b) in the flame-retardant leather-like sheet substrate is 10:90 to 90:10 by mass.

Abstract: A leather-like sheet material comprising a substrate layer composed of an entangled nonwoven fabric consisting of ultrafine fibers and an elastic polymer or elastomer filled therein and having, on one side (side A) of the substrate layer, a grain layer comprising an elastomer mainly consisting of a polyurethane, wherein the ultrafine fibers (a) constituting the side A of the substrate layer have a mean fineness substantially within the range of 0.01 to 0.5 decitex and the ultrafine fibers (b) substantially constituting the other side (side B) opposite to the side A of the substrate layer have a mean fineness of not more than ½ of the mean fineness of the ultrafine fibers (a).

Abstract: The leather-like sheet substrate of the present invention comprises a fiber-entangled nonwoven fabric that comprises a microfine fiber bundle (A) and a microfine fiber bundle (B) in a blending ratio (A)/(B) of 30/70 to 70/30 by mass and a polymeric elastomer contained in the fiber-entangled nonwoven fabric. The microfine fiber bundle (A) comprises 10 to 100 microfine fibers each of which has a single fiber fineness of 0.5 dtex or less and which are made of an elastic polymer having a JIS A hardness of 90 to 97. The microfine fiber bundle (B) comprises a microfine fiber which has a single fiber fineness of 0.5 dtex or less and which is made of a non-elastic polymer. Because of its excellent stretchability in both the machine and transverse directions and drapeability, the leather-like sheet substrate is particularly suitable as the material for clothing.

Abstract: One embodiment of the invention relates to a laminated sheet material, including, in order: (A) a substrate layer having an inner surface and at least a partially napped outer surface and including: an entangled nonwoven first fabric including ultrafine fibers having a fineness of not more than 0.01 decitex; and a first elastomeric polymer impregnated in the first fabric; (B) an adhesive layer; and (C) a substrate layer, including: an entangled nonwoven second fabric including fibers having a fineness of not less than 0.05 decitex; and a second elastomeric polymer impregnated in the second fabric; wherein at least a portion of the napped outer surface is covered with a third polymer, the third polymer being solid at a temperature of 20-25° C. and having a melting point not lower than 60° C. and having an elongation at break of not more than 10%. Another embodiment of the present invention provides a shoe upper, that includes the above-mentioned laminated sheet material.

Abstract: A napped leather-like sheet material comprising an entangled nonwoven fabric composed of ultrafine fibers and an elastomer contained therein and having a nap made of ultrafine fibers on one or both sides thereof, which material is provided with a silk protein substance and a softening agent on the surface portion of the napped face or faces; and a method of producing the above napped leather-like sheet material which comprises applying a liquid containing a silk protein substance and a softening agent to the surface of a napped leather-like sheet material by, for example, a gravure printing or spraying technique.

Abstract: The flame-retardant leather-like sheet substrate of the present invention comprises a layer (A) that is made of an entangled nonwoven fabric comprising a polyester superfine fiber (a) of a single fiber fineness of 0.5 dtex or less containing no flame-retardant component and a flame-retardant polyester superfine fiber (b) of a single fiber fineness of 0.5 dtex or less containing a flame-retardant component in a ratio, (a)/(b), of 100/0 to 40/60 by mass, and a layer (B) that is made of an entangled nonwoven fabric comprising the polyester superfine fiber (a) and the flame-retardant polyester superfine fiber (b) in a ratio, (a)/(b), of 70/30 to 0/100 by mass. The entangled nonwoven fabrics of the layers (A) and (B) are impregnated with an elastomeric polymer (c) containing a flame-retardant component. The ratio of the polyester superfine fiber (a) and the flame-retardant polyester superfine fiber (b) in the flame-retardant leather-like sheet substrate is 10:90 to 90:10 by mass.

Abstract: An oil tone artificial leather sheet having a blend of an oily substance of viscosity 50-10,000 mPa·s at 30° C. and a supporting polymer on part or all of a nap surface of a napped sheet comprising a non-woven fabric of microfine fibers and polyurethane existing in the non-woven fabric, wherein raised fibers comprising the microfine fibers are present in part or all of at least one surface and are forming the nap surface, and which has a high-quality appearance, and the soft hand touch and touch of natural leather. The sheet is useful in, for example, the manufacture of shoes or the like.

Abstract: A leather-like sheet material comprising a substrate layer composed of an entangled nonwoven fabric consisting of ultrafine fibers and an elastic polymer or elastomer filled therein and having, on one side (side A) of the substrate layer, a grain layer comprising an elastomer mainly consisting of a polyurethane, wherein the ultrafine fibers (a) constituting the side A of the substrate layer have a mean fineness substantially within the range of 0.01 to 0.

Abstract: A leather-like sheet having naps on its surface and having writing effect, a high-class external appearance, hand touch and feel like natural leather, and folds like natural leather. When it is subjected to lasting shoemaking, it is possible to obtain shoes which have at its surface no unevenness and do not get out of shape. A leather-like sheet wherein the following fiber-entangled nonwoven fabrics (A) and (B) are stacked with an adhesive agent present in a discontinuous state: (A) a fiber-entangled nonwoven fabric containing an elastic polymer and comprising a microfine fiber (a) having a fineness of 0.1 denier or less, the surface opposite to its stacking surf ace being fluffed, and rupture elongations in the longitudinal and latitudinal directions thereof being 50% or more and 80% or more, respectively, and (B) a fiber-entangled nonwoven fabric containing an elastic polymer and comprising a microfine fiber (b) having a fineness of 0.

Abstract: A napped leather-like sheet material comprising an entangled nonwoven fabric composed of ultrafine fibers and an elastomer contained therein and having a nap made of ultrafine fibers on one or both sides thereof, which material is provided with a silk protein substance and a softening agent on the surface portion of the napped face or faces; and a method of producing the above napped leather-like sheet material which comprises applying a liquid containing a silk protein substance and a softening agent to the surface of a napped leather-like sheet material by, for example, a gravure printing or spraying technique.

Abstract: One embodiment of the invention relates to a laminated sheet material, including, in order: