A sheet-like article and a production method therefor (as amended)

Abstract

A sheet-like article is provided including a fibrous base material formed of ultrafine fibers and/or ultrafine fiber bundles provided with, as a binder, a polymer elastomer having a hydrophilic group, any thickness-directional cross section of the sheet-like article containing regions occupied by the polymer elastomer, the regions including independent regions each with a cross-sectional area of 50 μm 2 or more, the total area of the independent regions accounting for 0.1% or more and 5.0% or less of the cross-sectional area of the artificial leather in an observation view field. A production process is also provided for a sheet-like article including a fibrous base material formed of ultrafine fibers and, as a binder, a polymer elastomer having a hydrophilic group, the process including a step for adding an aqueous resin dispersion liquid containing a water-dispersed polymer elastomer and a viscosity improver to a fibrous base material and a step for coagulating the polymer elastomer in hot water at a temperature of 50° C. to 100° C.

1 . A sheet-like article comprising a fibrous base material formed of ultrafine fibers and/or ultrafine fiber bundles provided with, as a binder, a polymer elastomer having a hydrophilic group, any thickness-directional cross section of the sheet-like article containing regions occupied by the polymer elastomer, the regions including independent regions each with a cross-sectional area of 50 μm 2  or more, the total area of the independent regions accounting for 0.1% or more and 5.0% or less of the cross-sectional area of the artificial leather in an observation view field. 
     
     
         2 . A sheet-like article as claimed in  claim 1 , wherein 1% or more and 35% or less of the circumferences of the cross sections of the ultrafine fibers and/or ultrafine fiber bundles observed in a cross section made by cutting the sheet-like article in the thickness direction is covered by film of the polymer elastomer. 
     
     
         3 . A sheet-like article as claimed in  claim 1 , wherein the polymer elastomer has a crosslinked structure produced by using a crosslinking agent. 
     
     
         4 . A production method for a sheet-like article including a fibrous base material formed of ultrafine fibers and, as a binder, a polymer elastomer having a hydrophilic group, comprising a step for adding an aqueous resin dispersion liquid containing a water-dispersed polymer elastomer and a viscosity improver to a fibrous base material and a step for coagulating the polymer elastomer in hot water at a temperature of 50° C. to 100° C. 
     
     
         5 . A production method for a sheet-like article as claimed in  claim 4 , wherein the aqueous resin dispersion liquid has non-Newtonian properties. 
     
     
         6 . A production method for a sheet-like article as claimed in  claim 4 , wherein the viscosity improver is a nonionic viscosity improver. 
     
     
         7 . A production method for a sheet-like article as claimed in  claim 4 , wherein the aqueous resin dispersion liquid has thixotropic properties. 
     
     
         8 . A production method for a sheet-like article as claimed in  claim 4 , wherein the viscosity improver is a polysaccharide viscosity improver. 
     
     
         9 . A production method for a sheet-like article as claimed in  claim 4 , wherein the viscosity improver is guar gum. 
     
     
         10 . A production method for a sheet-like article as claimed in  claim 4 , wherein the aqueous resin dispersion liquid contains a thermosensitive coagulant. 
     
     
         11 . A production method for a sheet-like article as claimed in  claim 4 , wherein the aqueous resin dispersion liquid contains a crosslinking agent. 
     
     
         12 . A production method for a sheet-like article as claimed in  claim 4 , wherein the polymer elastomer is water-dispersed polyurethane.