Suede artificial leather and production method thereof

A suede artificial leather comprising a three-dimensional entangled body comprising a superfine fiber having a fineness of 0.2 dtex or less and an elastomeric polymer A impregnated in the three-dimensional entangled body, the suede artificial leather satisfying the following requirements (1) to (4):

• (1) a pigment A in an amount of 0.1 to 8% by mass is embedded in the superfine fiber, wherein the pigment A is at least one pigment selected from the group consisting of an organic pigment having an average particle size of 0.01 to 0.3 μm and carbon black having an average particle size of 0.01 to 0.3 μm;
• (2) a pigment B in an amount of 1 to 20% by mass is embedded in the elastomeric polymer A, wherein the pigment B is at least one pigment selected from the group consisting of an organic pigment having an average particle size of 0.05 to 0.6 μm and carbon black having an average particle size of 0.05 to 0.6 μm, or the pigment B is a pigment particle having an average particle size of 0.05 to 0.6 μm which comprises a mixture of an organic pigment with carbon black or at least one inorganic pigment,
• wherein the elastomeric polymer A is selected from the group consisting of a polyurethane and an acryl-polyurethane composite elastomeric polymer, which is transparent when made into a cast film and has a hot water swelling rate of 20% or less when measured immediately after immersion to a hot water of 130° C.;
• wherein the acryl-polyurethane composite elastomeric polymer is obtained by an emulsion polymerization of an ethylenically unsaturated monomer comprising a (meth)acrylic acid derivative and in the presence of an aqueous dispersion of a urethane resin and is crosslinked by copolymerizing a polyfunctional ethylenically unsaturated monomer selected from the group consisting of 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, divinylbenzene and allyl (meth)acrylate;
• wherein the polyurethane is obtained from the reaction of a diisocyanate component, a polymeric polyol component, a chain extender and a carboxyl group-containing diol and crosslinked with a crosslinking agent,
• wherein the diisocyanate component is an aliphatic diisocyanate or alicyclic diisocyanate and containing less than 10% by mass of an aromatic diisocyanate, wherein the aliphatic diisocyanate or alicyclic diisocyanate is selected from the group consisting of hexamethylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate and 4,4′-dicyclohexylmethane diisocyanate;
• wherein the polymeric polyol component of the polyurethane is selected from the group consisting of polyethylene glycol, polypropylene glycol, polytetramethylene glycol, poly(methyltetramethylene glycol), polybutylene adipate diol, polybutylene sebacate diol, polyhexamethylene adipate diol, poly(3-methyl-1,5-pentylene adipate) diol, poly(3-methyl-1,5-pentylerne sebacate) diol, polycaprolactone diol, polyhexamethylene carbonate diol, and poly(3-methyl-1,5-pentylene carbonate) diol;
• wherein the chain extender is selected from the group consisting of hydrazine, ethylenediamine, propylenediamine, hexamethylenediamine, nonamethylenediamine, xylylenediamine, isophoronediamine, piperazine, adipoyldihydrazide, isophthaloyldihydazide, diethylenetriamine, triethylenetrimine, ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,4-bis(β-hydroxyethoxy)benzene, 1,4-cyclohexanediol, trimethylolpropane, pentaerythritol, aminoethyl alcohol and aminopropyl alcohol;
• wherein the crosslinking agent reacts with the carboxyl group of the polyurethane and has oxazoline group, carbodiimide group, epoxy group, cyclocarbonate group, aziridine group or hydrazide group;
• (3) the ratio of the elastomeric polymer A to the three-dimensional entangled body is 15:85 to 60:40 by mass;
• and
• (4) an average raised nap length of the superfine fiber present on the surface of the suede artificial leather is 10 to 200 μm.