Napped artificial leather and method for producing same

Patent metadata

Field	Value
Publication number	US-11873606-B2
Application number	US-201917298124-A
Country	US
Kind code	B2
Filing date	Dec 10, 2019
Priority date	Dec 21, 2018
Publication date	Jan 16, 2024
Grant date	Jan 16, 2024

Abstract

Disclosed is a napped artificial leather napped including: a non-woven fabric that is an entangle body of ultrafine fibers; and an elastic polymer impregnated into the non-woven fabric, the napped artificial leather having, at least on one side thereof, a napped surface formed by napping the ultrafine fibers, wherein the ultrafine fibers contain 0.5 mass % or more of a pigment (A), the elastic polymer contains 0 to 0.01 mass % of a pigment (B), and the ultrafine fibers and the elastic polymer are undyed; the napped surface has a lightness L* value of 25 or less in a color coordinate space (L*a*b* color space); and a ratio of an area occupied by the elastic polymer, observed on the napped surface, to a total area of an area occupied by the ultrafine fibers and the area occupied by the elastic polymer is 0.5% or less.

First claim

The invention claimed is:

1. A napped artificial leather, comprising:
a non-woven fabric comprising an entangled body of ultrafine fibers; and
an elastic polymer impregnated into the non-woven fabric;
wherein:
the napped artificial leather comprises, at least on one side thereof, a napped surface formed by napping the ultrafine fibers;
the ultrafine fibers comprise a pigment (A) in an amount of 0.5 mass % or more;
the elastic polymer comprises a positive amount of a pigment (B) in an amount up to 0.01 mass %;
the ultrafine fibers and the elastic polymer are undyed;
the napped surface has a lightness value of 25 or less in a color coordinate space (L*a*b* color space); and
a ratio of an area occupied by the elastic polymer observed on the napped surface to a total area of an area occupied by the ultrafine fibers observed on the napped surface and the area occupied by the elastic polymer observed on the napped surface is 0.5% or less.

2. The napped artificial leather according to claim 1 , wherein the ultrafine fibers comprise the pigment (A) in an amount of 0.5 to 10 mass %.

3. The napped artificial leather according to claim 1 , wherein the ultrafine fibers comprise the pigment (A) in an amount of 1.5 to 7 mass %.

4. The napped artificial leather according to claim 1 , wherein the napped artificial leather comprises the elastic polymer in an amount of 0.1 to 15 mass %.

5. The napped artificial leather according to claim 1 , wherein the ultrafine fibers have a fineness of 1 dtex or less.

6. The napped artificial leather according to claim 1 , wherein the lightness L* value is 21 or less.

7. A method for producing the napped artificial leather according to claim 1 , comprising:
preparing a first non-woven fabric comprising an entangled body of ultrafine fiber-generating fibers for forming the ultrafine fibers;
fully impregnating, into voids of the first non-woven fabric, an emulsion for forming the elastic polymer, and subsequently removing a part of the emulsion by squeezing off;
solidifying the elastic polymer in the emulsion applied into the voids of the first non-woven fabric;
forming the ultrafine fibers from the ultrafine fiber-generating fibers to form an artificial leather gray fabric including a second non-woven fabric comprising an entangled body of the ultrafine fibers; and
buffing at least one side of the artificial leather gray fabric;
wherein a squeezing rate at which a part of the emulsion is squeezed off is 30 to 50%.

8. The method according to claim 7 , wherein the emulsion further comprises a gelling agent.

9. The napped artificial leather according to claim 1 , wherein:
the ratio of the area occupied by the elastic polymer observed on the napped surface to a total area of the area occupied by the ultrafine fibers observed on the napped surface and the area occupied by the elastic polymer observed on the napped surface is 0.4% or less;
the ultrafine fibers comprise the pigment (A) in an amount of 0.5 to 10 mass %;
the napped artificial leather comprises the elastic polymer in an amount of 0.1 to 15 mass %;
the ultrafine fibers have a fineness of 0.1 to 0.5 dtex;
the lightness L* value is 21 or less;
the napped artificial leather has a thickness of 0.3 to 1.5 mm; and
the napped artificial leather has an apparent density of 0.4 to 0.7 g/cm 3 .

Assignees

• Kuraray Co

Inventors

• Hattori Hiroyuki
• Katou Yasuhiro
• Suetoshi Kazuyuki
• Nagayama Rei

Classifications

• D06N3/0075 Primary

  Napping, teasing, raising or abrading of the resin coating (raising, napping of the web before coating D06N3/004) · CPC title

• D06N3/0011 Primary

  using non-woven fabrics · CPC title

• D06N3/0077

  Embossing; Pressing of the surface; Tumbling and crumbling; Cracking; Cooling; Heating, e.g. mirror finish · CPC title

• D06N3/14

  with polyurethanes · CPC title

• D06N2201/0209

  Elastomeric, elastic fibres, e.g. spandex, lycra · CPC title