The present invention relates to a polycarbonate diol comprising a structural unit derived from a compound represented by the following formula (A) and a structural unit derived from a compound represented by the following formula (B), wherein the hydroxyl value is from 20 to 450 mg-KOH/g:
HO—R.sup.1—OH  (A)
HO—R.sup.2—OH  (B) the glass transition temperature of said polycarbonate diol as measured by a differential operating calorimeter is −30° C. or less and the average carbon number of a dihydroxy compound obtained by hydrolyzing said polycarbonate diol is from 3 to 5.5.

An aqueous polyurethane resin dispersion has a non-volatile content of not less than 40% by mass and includes polyurethane resin particles dispersed in water. The polyurethane resin particles contain a polyol component, an isocyanate component, and a hydrophilic alkylene oxide component having at least one active hydrogen group and an alkylene oxide. The content of the hydrophilic alkylene oxide component in the polyurethane resin particles is 1 to 25% by mass. The volume average particle size of the polyurethane resin particles is 0.3 to 5 μm.

Disclosed are a soft solvent-free flame-retardant polyurethane synthetic leather and a preparation method therefor. The soft solvent-free flame-retardant polyurethane synthetic leather comprises an antifouling layer, a surface layer, an intermediate layer, a bonding layer and a base cloth in sequence from top to bottom, wherein the bonding layer is prepared from component A and an isocyanate; the molar ratio of —NCO in the isocyanate to —OH in the component A is 0.85-0.93; and the component A is composed of a polyhydric alcohol, an inhibition-type catalyst, a flame retardant, a filler and a viscosity modifier in parts by weight.

The present invention provides a sheet-like material having soft texture, durability capable of withstanding practical use, and abrasion resistance. The sheet-like material of the present invention is a sheet-like material containing a nonwoven fabric composed of an ultrafine fiber having an average single fiber diameter 0.3 to 7 μm; and an elastic resin, wherein the elastic resin is a polyurethane resin (D) which contains: as essential constituent monomers, a copolymerized polycarbonate diol (A1) which contains a structural unit derived from C3-5 alkane diol (a1) and a structural unit derived from C8-12 alkane diol (a2), the molar ratio of the alkanediol (a2) with respect to the total number of moles of the alkanediol (a1) and the alkanediol (a2) being 50 to 95 mole %; a polycarbonate diol (A2) containing a structural unit derived from a C4-6 alkane diol (a3); an organic diisocyanate (B); and a chain extender (C), and the polyurethane resin (D) satisfies the following conditions (1) to (3): (1) The copolymerized polycarbonate diol (A1) has a heat quantity of fusion (ΔH) o 40 to 100 J/g, the heat quantity of fusion (ΔH) being determined according to a melting point measuring method provided in JIS K7121-1987; (2) The polycarbonate diol (A2) has a heat quantity of fusion (ΔH) of 0 J/g; (3) A difference (ΔTm) in a melting point (Tm) between a mixture (A12) of the copolymerized polycarbonate diol (A1) with the polycarbonate diol (A2) and the copolymerized polycarbonate diol (A1) is 1.5° C. or lower, the melting point (Tm) being determined by a melting point measuring method provided in JIS K7121-1987.

The present disclosure provides a polyurethane dispersion comprising a polyurethane prepolymer and an ionic surfactant. It further provides a microfiber nonwoven synthetic leather comprising a microfiber nonwoven fabric and the polyurethane dispersion. It further provides a method of preparing the microfiber nonwoven synthetic leather comprising a step of impregnating microfiber nonwoven fabrics into the polyurethane dispersion.

In the present invention, there is provided an urethane resin composition containing an urethane resin (A), water (B), and a surfactant (C) having no aromatic ring, and having a hydrophobic portion having 10 or more carbon atoms, wherein the urethane resin composition has a carbonate structure (X) and an oxyalkylene structure (Y) derived from the urethane resin (A). Further, the present invention provides a foamed urethane sheet which is formed from the urethane resin composition, wherein the foamed urethane sheet has a density of 200 to 1,000 kg/m.sup.3. The urethane resin composition according to claim 1, wherein the mass ratio of the carbonate structure (X) to the oxyalkylene structure (Y) [X/Y] is in the range of from 10/90 to 90/10.

A synthetic leather has excellent flame retardance and an article covered with the synthetic. The synthetic leather includes a fiber base material layer formed of a non-woven fabric sheet, wherein the non-woven fabric sheet includes at least one flameproof layer formed of a web including a non-melting fiber A having a high-temperature shrinkage rate of 3% or less and a thermal conductivity, conforming to ISO22007-3 (2008), of 0.060 W/m.Math.K or less and is formed by bonding the flameproof layer to a scrim layer including a carbonized heat-resistant fiber B having an LOI value, conforming to JIS K 7201-2 (2007), of 25 or more, and a resin layer is laminated on a surface of the scrim layer, and a covered article covered with the synthetic leather.

Provided is a synthetic leather including a fibrous substrate, a porous resin layer provided on the fibrous substrate, and a non-porous resin layer provided on the porous resin layer. The synthetic leather has a thickness of 800 μm or more, and a vertical cross-section of the porous resin layer has a pore area ratio of 25% or more.

A method for producing a polyurethane foam sheet, including applying, in sheet form, a mixture obtained by mixing a moisture-curable polyurethane hot melt resin composition (X) containing a urethane prepolymer (i), which is a reaction product between a polyol (A) and a polyisocyanate (B), with a polyol composition (Y) onto a substrate, and bringing the mixture in the sheet form into contact with water vapor to moisture-foam the mixture. The method for producing a polyurethane foam sheet is characterized in that the polyol (A) contains a polytetramethylene glycol or polycarbonate polyol (a1) and a polyol (a2) having a structure derived from an alkylene oxide adduct of bisphenol A, and the polyol composition (Y) contains an amine catalyst (y1) having a foaming constant (Kw) of 10 or more.

The present disclosure relates to a multilayer synthetic leather, at least comprising a textile arrangement; and a polyurethane based foam; wherein the polyurethane-based foam is partially fixed to the textile arrangement using a first fixing layer such that the first fixing layer has fixing areas formed by a fixing agent and free areas free from the fixing agent in the same plane.