Microfibrous fabric having a suede appearance, within the colour range of grey and black, with a high light fastness, and preparation method thereof

Abstract

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 2 being higher than or equal to 4; the lightfastness of the colors according to the method SAE J 1885 488.8 KJ/m 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.

We claim: 
     
         1 . A non-woven artificial leather, having a suede appearance, said non-woven artificial leather consisting essentially of a non-woven microfibrous component and an elastomeric matrix; the non-woven microfibrous component comprising polyester microfibres having a count of 0.01 to 0.50 dtex and carbon black pigment in a percentage of 0.05 to 2.00% by weight; the elastomeric matrix comprising polyurethane comprising soft and hard segments and carbon black pigment in a percentage of 0 to 10% by weight;
 wherein the soft segments comprise at least one polycarbonate diol selected from polyalkylene carbonate diols, and at least one polyester diol;   wherein the hard segments comprise urethane groups deriving from the reaction between free isocyanate groups and water; and   wherein part of the microfibrous component forms tassels on a surface of the artificial leather having an average length ranging from 210 to 400 microns, which provides an improved mottling effect and writing effect.   
     
     
         2 . The artificial leather according to  claim 1 , wherein the microfibrous component comprise polyethylene terephthalate microfibres. 
     
     
         3 . The artificial leather according to  claim 1 , wherein the polyester microfibres contain carbon black in a percentage of 0.15 to 1.50% by weight. 
     
     
         4 . The artificial leather according to  claim 1 , wherein the elastomeric matrix contains the carbon black pigment in a percentage ranging from 0 to 7% by weight. 
     
     
         5 . The artificial leather according to  claim 1 , wherein the elastomeric matrix comprises the carbon black pigment in a percentage ranging from 0.02% to 10% by weight. 
     
     
         6 . The artificial leather according to  claim 1 , wherein the elastomeric matrix comprises the carbon black pigment in a percentage ranging from 0.02% to 7% by weight. 
     
     
         7 . The artificial leather according to  claim 1 , wherein the elastomeric matrix comprises the carbon black pigment in a percentage ranging from 0.02% to 6% by weight. 
     
     
         8 . The artificial leather according to  claim 1 , wherein the overall content of carbon black ranges from 0.075 to 4.25% by weight. 
     
     
         9 . The artificial leather according to  claim 1 , wherein the overall content of carbon black ranges from 0.025 to 6% by weight. 
     
     
         10 . The artificial leather according to  claim 1 , wherein the overall content of carbon black ranges from 0.085 to 3.75% by weight. 
     
     
         11 . The artificial leather according to  claim 1 , wherein the carbon black has an average dimension lower than 0.4 microns. 
     
     
         12 . The artificial leather according to  claim 1  having a color shade within the grey-black range, wherein the light fastness of the color shade being higher than or equal to 4, according to the method SAE J 1885 225.6 KJ/m 2 , and not lower than 3, according to the method SAE J 1885 488.8 KJ/m 2 . 
     
     
         13 . The artificial leather according to  claim 1 , wherein
 the polyester diols are selected from the group consisting of polyhexamethylene adipate diol (PHA), poly(3-methylpentamethylene) adipate diol (PMPA), polyneopentyl adipate diol (PNA), and polycaprolactone diol (PCL);   the polyalkylenecarbonate diols are selected from the group consisting of polytetramethylene carbonate diol (PTMC), polypentamethylene carbonate diol (PPMC), polyhexamethylene carbonate diol (PHC), polyheptamethylene carbonate diol, polyoctamethylene carbonate diol, polynonamethylene carbonate diol, polydecamethylene carbonate diol, poly-(2-methyl-pentamethylene carbonate)diol, and poly-(2-methyl-1-octamethylene carbonate) diol; and   the isocyanate groups are derived from methylene-bis-(4-phenylisocyanate) (MDI) and/or from toluene diisocyanate (TDI).   
     
     
         14 . The artificial leather according to  claim 1 , wherein the color shade is characterized by a value of “L”<70, wherein said value is measured before the artificial leather is subjected to an over-dyeing treatment. 
     
     
         15 . The artificial leather according to  claim 14 , wherein the color shade is characterized by a value of “L”<55. 
     
     
         16 . The artificial leather according to  claim 1 , wherein the polyester diol is polyhexamethylene adipate diol (PHA). 
     
     
         17 . The artificial leather according to  claim 1 , wherein the hard segment of said polyurethane further comprises one or more compounds selected from the group consisting of 2,2-dimethylol-propanoic acid, 2,2-dimethylol-butanoic acid, N-methyl-diethanolamine, dihydroxy alkyl amines, di-amino-alkyl amines, quaternary ammonium salts, and polyoxyalkyl ethers. 
     
     
         18 . The artificial leather according to  claim 1 , wherein the tassels on the surface of the artificial leather have an average length ranging from 210 to 370 microns. 
     
     
         19 . The artificial leather according to  claim 1 , wherein the tassels on the surface of the artificial leather have an average length ranging from 210 to 350 microns.