Coated and expanded, nanofiber structures are provided and methods of use thereof.

A production method of an elastically stretchable artificial leather which includes a step of making microfiberizable fibers into a web; a step of entangling the obtained web to produce an entangled nonwoven fabric; a step of converting the microfiberizable fibers in the nonwoven fabric to microfine fibers, thereby producing a substrate for artificial leather; a step of producing an artificial leather by using the obtained substrate for artificial leather; and a step wherein the obtained artificial leather is brought into close contact with an elastomer sheet stretched in a machine direction by 5 to 40%; the artificial leather is allowed to shrink in the machine direction simultaneously with allowing the elastomer sheet to shrink in the machine direction by relaxing elongation of the elastomer sheet; the artificial leather is heat-treated in shrunk state; and then the artificial leather is peeled off from the elastomer sheet.

An artificial leather including a base layer and a surface layer which is formed on one of surfaces of the base layer. The base layer includes bundles of microfine filaments and an elastic polymer. The surface layer includes the microfine filaments or includes the microfine filaments and the elastic polymer. The surface layer satisfies the relationship of X/Y1.5 wherein X is the number of cut ends of the microfine filaments which exist in a region from a surface to a 20 m depth in a cross section of the artificial leather, Y is the number of cut ends of the microfine filaments which exist in a region from a surface to a 20 m depth in a cross section perpendicular to the cross section for determining X, and X>Y. The artificial leather having such surface layer exhibits a sufficient gloss without coating a pigment such as metallic powder.

An automobile instrument panel surface material includes a microfiber having an average single fiber diameter of 0.3 to 7 m; and polyurethane, the automobile instrument panel surface material having nap formed of the microfiber, the automobile instrument panel surface material having, of light fastnesses measured according to a light fastness measurement method of JIS L 0843:2006 under conditions of a xenon arc intensity of 110 MJ/m2, a fading by gray scale evaluation of grade 3.5 or higher, the automobile instrument panel surface material having a glass haze of 10.0% or less as measured according to a glass haze evaluation method of ISO 6452:2007 under conditions of a heating temperature of 100 C. and a heating time of 20 hours.

Disclosed is a leather-like sheet having a lightness L* of 35 or less, and including a fiber structure including fiber dyed with a dye composition including C.I. Basic Blue 3 and at least one blue cationic dye other than C.I. Basic Blue 3, and an elastic polymer contained in internal voids of the fiber structure, or the fiber structure. Also disclosed is a leather-like sheet having a lightness L* of 35 or less, and including a fiber structure including fiber dyed with an azo-based blue cationic dye, and an elastic polymer contained in internal voids of the fiber structure, wherein the leather-like sheet or the fiber structure has a color difference (E), determined when treated for 48 hours under moist and hot conditions of 80 C. and a moisture of 90%, of E2. or the fiber structure

A dyed artificial leather includes a fibrous base containing ultrafine fibers with a filament fineness of 2 decitex or less and a polymeric elastomer, and characterized in that the lightness difference L* between the ultrafine fibers and the polymeric elastomer represented by the following equation meet the requirement of 16L*5: L*=(average lightness L* of ultrafine fibers)(average lightness L* of polymeric elastomer). A production method for dyed artificial leather includes a first dying step in which artificial leather constituted mainly of a fibrous base containing ultrafine fibers with a filament fineness of 2 decitex or less and a polymeric elastomer is dyed using a dye and a subsequent second dyeing step performed at a dye concentration that is 0.1% to 30% of the dye concentration (owf) in the first dyeing step.

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.

A high-quality artificial leather is described, having a suede appearance and colors within the grey-black range, the light fastness of the colors according to the method SAE J 1885 225.6 KJ/m.sup.2 being higher than or equal to 4; the lightfastness of the colors according to the method SAE J 1885 488.8 KJ/m.sup.2 being not lower than 3; said artificial leather having a tassel on the surface of the leather itself. The average length of the tassel is between 200 and 500 microns. The soft segments consist of at least one polycarbonate diol selected from polyalkylene carbonate diols and at least one polyester diol; the hard segments consist of urethane groups deriving from the reaction between free isocyanate groups and water; and the total content of carbon black is between 0.025 and 6% by weight.

The present invention refers to a process for the preparation of a non-woven microfibrous suede-like synthetic fabric that does not require the use of organic solvents and that makes it possible to obtain a finished product offering a good hand, excellent resistance to yellowing and high durability. It comprises needle-punching a felt of sea/island fibers, (a) impregnation with hot aqueous solution of PVOH having a degree of saponification of at least 94% or (b) impregnation with hot water followed by impregnation with cold PUR, removing the sea component, impregnating with PUR, coagulating the PUR, removing the PVOH, grinding the surface, dyeing and splitting in two sheets.

Coated and expanded, nanofiber structures are provided and methods of use thereof.