1 : A napped artificial leather, comprising: a non-woven fabric that is an entangle body of ultrafine fibers; and an elastic polymer applied into the non-woven fabric, the napped artificial leather having, on at least one side thereof, a napped surface formed by napping the ultrafine fibers, wherein each of the ultrafine fibers is an ultrafine fiber having a fineness of 0.5 dtex or less and a tensile strength of 6 to 9 mN, and a plurality of the ultrafine fibers form a fiber bundle, the ultrafine fibers that form the fiber bundle are not constrained by the elastic polymer in a region of the napped artificial leather other than a surface layer portion, a content ratio of the elastic polymer is 16 to 40 mass %, and the napped artificial leather has an apparent density of 0.38 g/cm 3 or more.
2 : The napped artificial leather according to claim 1 , wherein the tensile strength is a tensile strength A (mN) in the range of 6.5 to 8 mN, the apparent density is 0.38 to 0.48 g/cm 3 , and a content ratio B (%) of the elastic polymer satisfies 3.125×A≤B.
3 : The napped artificial leather according to claim 1 , wherein the elastic polymer is a nonaqueous solvent-based polyurethane.
4 : The napped artificial leather according to claim 1 , wherein the elastic polymer has an expansion ratio of 0 to 5 mass %.
5 : The napped artificial leather according to claim 1 , wherein a portion of the elastic polymer that is present in the surface layer portion is fixed to the vicinity of a base of the napped ultrafine fibers.
6 : The napped artificial leather according to claim 1 , wherein each of the ultrafine fibers is an ultrafine fiber formed by removing by dissolution a sea component from an island-in-the-sea composite fiber, using an organic solvent.
7 : The napped artificial leather according to claim 1 , wherein the non-woven fabric is a spunbonded non-woven fabric including the ultrafine filaments.
8 : The napped artificial leather according to claim 3 , wherein the nonaqueous solvent-based polyurethane is a polyurethane that solidified from a polyurethane-solution including N,N-dimethylformamide, by wet coagulation.
9 : A napped artificial leather, comprising: a non-woven fabric that is an entangle body of ultrafine filaments; and an elastic polymer applied into the non-woven fabric, the napped artificial leather having, on at least one side thereof, a napped surface formed by napping the ultrafine fibers, wherein each of the ultrafine fibers is an ultrafine fiber having a fineness of 0.15 to 0.5 dtex and a tensile strength of 6.5 to 8 mN, and a plurality of the ultrafine fibers form a fiber bundle, the ultrafine fibers that form the fiber bundle are not constrained by the elastic polymer in a region of the napped artificial leather other than a surface layer portion, a content ratio of the elastic polymer is 16 to 40 mass % and the elastic polymer is a nonaqueous solvent-based polyurethane, the napped artificial leather has an apparent density of 0.38 g/cm 3 or more, and the tensile strength A (mN) and the content ratio B (%) of the elastic polymer satisfies 3.125×A≤B.
10 : The napped artificial leather according to claim 9 , wherein the nonaqueous solvent-based polyurethane is a polyurethane that solidified from a polyurethane-solution including N,N-dimethylformamide, by wet coagulation.
11 : The napped artificial leather according to claim 9 , wherein the elastic polymer has an expansion ratio of 0 to 5 mass %.
12 : The napped artificial leather according to claim 9 , wherein a portion of the elastic polymer that is present in the surface layer portion is fixed to the vicinity of a base of the napped ultrafine fibers.
13 : The napped artificial leather according to claim 11 , wherein a portion of the elastic polymer that is present in the surface layer portion is fixed to the vicinity of a base of the napped ultrafine fibers.
14 : The napped artificial leather according to claim 9 , wherein the non-woven fabric is a spunbonded non-woven fabric including the ultrafine fibers.
15 : A napped artificial leather, comprising: a non-woven fabric that is an entangle body of ultrafine fibers; and an elastic polymer applied into the non-woven fabric, the napped artificial leather having, on at least one side thereof, a napped surface formed by napping the ultrafine fibers, wherein each of the ultrafine fibers is an ultrafine fiber having a fineness of 0.15 to 0.5 dtex and a tensile strength of 6.5 to 8 mN, and a plurality of the ultrafine fibers form a fiber bundle, a content ratio of the elastic polymer is 16 to 40 mass %, and the elastic polymer is a nonaqueous solvent-based polyurethane and has an expansion ratio of 0 to 5 mass %, the ultrafine fibers that form the fiber bundle are not constrained by the elastic polymer in a region of the napped artificial leather other than a surface layer portion, and the elastic polymer that is present in the surface layer portion is fixed to the vicinity of a base of the napped ultrafine fibers, the napped artificial leather has an apparent density of 0.38 g/cm 3 or more, and the tensile strength A (mN) and the content ratio B (%) of the elastic polymer satisfies 3.125×A≤B.
16 : The napped artificial leather according to claim 15 , wherein the nonaqueous solvent-based polyurethane is a polyurethane that solidified from a polyurethane-solution including N,N-dimethylformamide, by wet coagulation.
17 : The napped artificial leather according to claim 15 , wherein the non-woven fabric is a spunbonded non-woven fabric including the ultrafine fibers.
