US 7,932,192 B2 · Base for synthetic leather and synthetic leathers made by using the same

Abstract

A substrate for artificial leathers, comprising a nonwoven fabric body made of microfine fiber bundles and an elastic polymer impregnated therein. The substrate for artificial leathers simultaneously satisfies the following requirements 1 to 4: (1) each of the microfine fiber bundles contains 6 to 150 bundled microfine long fibers in average; (2) a cross-sectional area of the microfine long fibers constituting the microfine fiber bundles is 27 μm2 or less, and 80% or more of the microfine long fibers has a cross-sectional area of from 0.9 to 25 μm2; (3) an average cross-sectional area of the microfine fiber bundles is from 15 to 150 μm2; and (4) 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 from 1000 to 3000/mm2 in average. The raised artificial leathers and grain-finished artificial leathers made from the substrate for artificial leathers are excellent in the properties which are hitherto difficult to be combined.

Claims11

Dependent claims

A substrate comprising a nonwoven fabric body made of microfine fiber bundles and an elastic polymer impregnated therein, which simultaneously satisfies the following requirements 1 to 4:

(1) each of the microfine fiber bundles comprises 6 to 150 bundled microfine long fibers in average;
(2) a cross-sectional area of the microfine long fibers constituting the microfine fiber bundles is 27 μm2 or less, and 80% or more of the microfine long fibers has a cross-sectional area of from 0.9 to 25 μm2;
(3) an average cross-sectional area of the microfine fiber bundles is from 15 to 150 μm2;
and
(4) 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 from 1000 to 3000/mm2 in average.

2 more elements

A method of producing a substrate which comprises the following (a), (b), (c) and (d) in this order, or the following (a), (b), (d) and (c) in this order:

(a) melt-spinning sea-island fibers having an average island number of 6 to 150, a ratio of an average sea cross-sectional area and an average island cross-sectional area of 5:95 to 70:30, and an average cross-sectional area of 30 to 180 μm2, and then, colleting the sea-island fibers in random directions on a collecting surface without cutting, thereby obtaining a long fiber web;
(b) entangling the sea-island fibers three-dimensionally by needle-punching the long fiber web from both surfaces thereof so as to allow at least one barb to penetrate through the long fiber web optionally after superposing two or more long fiber webs, and then, optionally shrinking or heat-pressing the needle-punched long fiber web for densification and/or fixation, thereby obtaining a nonwoven fabric body in which cross sections of the sea-island fibers exist on a cross section parallel to a thickness direction of the nonwoven fabric body in a density of from 600 to 4000/mm2 in average;
(c) impregnating a solution of an elastic polymer into the nonwoven fabric body and coagulating the elastic polymer by a wet method;
and
(d) removing a sea component polymer from the sea-island fibers constituting the nonwoven fabric body by extraction or decomposition, thereby converting the sea-island fibers to microfine fiber bundles.

2 more elements

Dependencies are inferred from the claim text.

Base for synthetic leather and synthetic leathers made by using the same

Life of this patent

Base for synthetic leather and synthetic leathers made by using the same

Life of this patent

Abstract

Claims11