Elastic artificial leather and production method therefor

Patent metadata

Field	Value
Publication number	US-11268237-B2
Application number	US-201916440117-A
Country	US
Kind code	B2
Filing date	Jun 13, 2019
Priority date	Feb 29, 2012
Publication date	Mar 8, 2022
Grant date	Mar 8, 2022

Abstract

Disclosed herein is a method for producing an elastically stretchable artificial leather, which includes the steps of forming microfiberizable fibers into a web, entangling the obtained web to produce an entangled nonwoven fabric, converting the microfiberizable fibers in the nonwoven fabric to microfine fibers thereby producing a substrate for artificial leather, producing an artificial leather from the obtained substrate for artificial leather, bringing the obtained artificial leather into close contact with an elastomer sheet stretched in a machine direction by 5 to 40%, shrinking the artificial leather in the machine direction simultaneously with the elastomer sheet by relaxing elongation of the elastomer sheet to obtain an artificial leather in shrunk state, heat treating the artificial leather in shrunk state, and then peeling the heat treated artificial leather off from the elastomer sheet.

First claim

What is claimed is:

1. A method of producing an elastically stretchable artificial leather comprising:
forming microfiberizable fibers into a web;
entangling the obtained web to produce an entangled nonwoven fabric;
converting the microfiberizable fibers in the nonwoven fabric to microfine fibers, thereby producing a substrate for artificial leather;
producing an artificial leather from the obtained substrate for artificial leather;
bringing the obtained artificial leather into close contact with an elastomer sheet stretched in a machine direction by 5 to 40%,
shrinking the artificial leather in the machine direction simultaneously with the elastomer sheet by relaxing elongation of the elastomer sheet to obtain an artificial leather in shrunk state,
heat treating the artificial leather in shrunk state; and
peeling the heat treated artificial leather off from the elastomer sheet thereby producing the elastically stretchable artificial leather.

2. The method according to claim 1 , wherein the method further comprises impregnating an elastic polymer into the entangled nonwoven fabric or the substrate for artificial leather and then coagulating the impregnated elastic polymer.

3. The method according to claim 1 , wherein the elastomer sheet is a natural rubber sheet or a synthetic rubber sheet.

4. The method according to claim 1 , wherein
the elastomer sheet is stretched in the machine direction by utilizing a difference between inner and outer circumferences of the curved elastomer sheet that is run in contact with a surface of a cylinder, or by utilizing an elongation when compressing the elastomer sheet; and
the elastomer sheet is shrunk in the machine direction by relaxing the stretched state, thereby allowing the artificial leather to shrink in the machine direction.

5. The method according to claim 1 , wherein the elastomer sheet has a thickness of 40 to 75 mm.

6. The method according to claim 4 , wherein the elastomer sheet runs along a cylinder while holding the artificial leather therebetween, thereby allowing a surface in contact with the artificial leather to shrink in the machine direction.

7. The method according to claim 6 , wherein an apparent coefficient of dynamic friction between the elastomer sheet and the artificial leather is from 0.8 to 1.7 and a coefficient of dynamic friction between the cylinder and the artificial leather is 0.5 or less.

8. The method according to claim 6 , wherein the cylinder is a heated cylinder.

9. The method according to claim 1 , wherein the artificial leather is subjected to a pre-heating treatment, a humidifying treatment, or both before contacting the elastomer sheet.

10. The method according to claim 2 , wherein the elastic polymer is a coagulated product of an aqueous emulsion of polyurethane.

11. The method according to claim 1 , wherein the microfine fiber is a non-elastic fiber.

12. The method according to claim 1 , further comprising
cooling the artificial leather immediately after peeling off from the elastomer sheet to 85° C. or lower or
conveying the artificial leather by a belt.

Assignees

• Kuraray Co

Inventors

• Fujisawa Michinori
• Maeda Yukio
• Inoue Kazumasa
• Nomura Yasutoshi
• Ashida Tetsuya
• Watanabe Hisaichi

Classifications

• D06N3/0004 Primary

  using ultra-fine two-component fibres, e.g. island/sea, or ultra-fine one component fibres (< 1 denier) · CPC title

• D06N3/0029

  Stretchable fibres; Stretching of fibres during manufacture · CPC title

• D06N3/0036

  Polyester fibres (for elastomeric fibres D06N3/0025) · CPC title

• D06N3/0027 Primary

  Rubber or elastomeric fibres · CPC title

• D06N2211/28

  Artificial leather · CPC title