TWI472663B - A polyurethane sheet material group formed on the fibrous laminate and an artificial leather using the same and a method of manufacturing the same - Google Patents

Description

Polyurethane surface material group formed on fiber laminate and artificial leather using the same and manufacturing method thereof

The present invention relates to a polyurethane resin skin material group formed on a fiber laminate, an artificial leather using the same, and a method of producing the same.

Synthetic leather or artificial leather is used, for example, as a bag or a shoe. These synthetic leathers and the like are required to have flexibility, resilience, strength, stretchability, and air permeability depending on the use environment and conditions of the synthetic leather or the like.

The term "synthetic leather" as used herein generally means to form various resin films on a base fabric (a laminate, a substrate or a woven fabric) composed of a woven fabric or a woven fabric as a base. On the other hand, artificial leather generally means that a urethane resin film is formed on a base fabric composed of a non-woven fabric as a base. However, recently, for synthetic leather and artificial leather, the types of base fabrics and resins used for each of them are diversified, and the clear distinction between the two is not obvious. Synthetic leather and artificial leather are items that can be provided inexpensively. Not only the touch or appearance of the skin is indistinguishable from natural leather at first sight, but also has high durability. Therefore, in this specification, synthetic leather and artificial leather are collectively referred to as artificial leather, and the base fabric using artificial leather is a laminate. In addition, artificial leather generally includes polyethylene leather, but polyethylene leather is not excluded from the category of artificial leather because it is not based on polyurethane resin.

On the other hand, the artificial leather manufacturing method is generally a direct application coating resin (hereinafter referred to as a urethane resin surface layer material formed on a laminate) on a base fabric or the like or by coating on a release paper. Written in methods such as base cloth. For this reason, the organic solvent evaporates when the coating resin is applied, and environmental problems, labor safety and hygiene problems occur, and even the necessary equipment investment for the equipment for solving the problem is increased.

In order to improve the problem, a technique in which an aqueous polyurethane coating agent is applied to synthetic leather or the like has been proposed (for example, refer to Patent Document 1).

However, a production system using an aqueous coating agent causes a problem of an increase in so-called energy cost due to high evaporation energy of water. Further, it is not possible to obtain an aqueous coating agent such as synthetic leather that satisfies all of productivity, strength, and environmental compatibility.

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2006-104251

SUMMARY OF THE INVENTION An object of the present invention is to provide a polyurethane resin skin material group formed on a fiber laminate which is excellent in balance between strength and flexibility, and a production environment, and an artificial leather using the same and a method for producing the same.

That is, the present invention is as shown in the following (1) to (6).

(1) A polyurethane resin surface layer material group formed on a fiber laminate, which is a base agent (A) composed of a polycarbonate diol obtained by reacting 1,6-hexanediol and a low molecular carbonate. And a hexamethylene diisocyanate-modified polyisocyanate (B1) having a number average molecular weight of 350 to 500 and an average functional group number (f1) of 2 or less and f1 of less than 3, and a hexamethylene diisocyanate having an average functional group number (f2) of f2 or more and 3 or more The hardener (B) composed of the isocyanurate-modified polyisocyanate (B2), and the mass ratio of (B1) and (B2) is (B1): (B2) = 50:50 to 95:5 .

(2) In the polyurethane resin surface layer material group formed on the fiber laminate, the hexamethylene diisocyanate-modified polyisocyanate (B1) includes an allophanate obtained by a reaction of a low molecular monool with hexamethylene diisocyanate. Modified isocyanate.

(3) An artificial leather comprising a surface layer formed using the urethane resin surface layer material formed on the fiber laminate, and a weiweiwei layer covered by the surface layer.

(4) A method for producing an artificial leather, comprising applying a solution of a urethane resin surface layer material group formed on the fiber laminate to a release support, and once hardening, bonding to a bismuth cloth to perform secondary hardening. This release support is then removed.

(5) A method for producing artificial leather, which is directly coated with a solution of a urethane resin surface layer material group formed on the above-mentioned fiber laminate, and heat-cured.

(6) In the method for producing artificial leather described above, the molar ratio of the hydroxyl group to the isocyanate group in the solution of the polyurethane resin surface layer material group formed on the fiber laminate is hydroxyl group/isocyanate group = 90/100 to 110/100.

The present invention provides a polyurethane resin surface material group formed on a fibrous laminate which is excellent in balance between strength and flexibility, and which is excellent in production environment, and artificial leather using the same and a method for producing the same.

The polyurethane resin surface material group (hereinafter referred to as a material group) formed on the fiber laminate of the present embodiment is a specific polycarbonate diol (hereinafter referred to as PCD) and a hardener (B) which will be described later in detail in the main component (A). a modified polyisocyanate (B1) having a number average molecular weight of 350 to 500 and having a low functional number of hexamethylene diisocyanate (hereinafter referred to as HDI) and HDI isocyanurate-modified polyisocyanate (B2) Composition.

The material group, whether the main agent (A) or the hardener (B), is an aqueous coating agent containing no organic solvent. Further, the material group may be a pre-mixture of the polyol obtained by pre-mixing the main agent (A) and the hardener (B), preferably managing the main agent (A) and the hardener (B) separately, and forming a surface layer. At the same time, the curing catalyst is used together. Thereby, the storage stability at the time of long-term storage is good before the use of the main agent (A) and the hardener (B).

The PCD in the main component (A) is a PCD obtained by subjecting 1,6-hexanediol (hereinafter referred to as 1,6-HD) to a dealcoholization reaction or a dephenolation reaction with a low molecular carbonate. The number average molecular weight of this PCD is preferably from 500 to 5,000, more preferably from 1,000 to 3,000. When the number average molecular weight is too low, the flexibility of the coating agent is lowered, and the followability of the touch or the substrate is also lowered. On the other hand, when the number average molecular weight is high, the strength of the coating film is insufficient.

PCD can also be obtained using a low molecular polyol other than 1,6-HD and used in the main agent (A) of the coating agent. The low molecular polyalcohol other than 1,6-HD is, for example, ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4- Butylene glycol, 1,5-pentanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 2-ethyl-4-butyl -1,3-propanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid glycol, double An ethylene oxide or a propylene oxide additive of phenol A, a low molecular polyalcohol such as bis(β-hydroxyethyl)benzene, decyl alcohol, glycerin, trimethylolpropane or pentaerythritol.

The low molecular carbonate is, for example, ethylene carbonate, diethyl carbonate, diphenyl carbonate or the like.

Further, when a chain extender is used, there is no problem in that the main component (A) and the hardener (B) are not mixed before the formation of the surface layer, but the premixed main agent (A) and the hardener are used in forming the surface layer ( B) As a pre-mix of polyalcohol, there is a risk of causing a transesterification reaction when storing the polyalcohol premix.

The hardener (B) is composed of an HDI-modified polyisocyanate (B1) having a number average molecular weight of 350 to 500 and having a low functional group as described below and a HDI isocyanurate-modified polyisocyanate (B2).

The HDI-modified polyisocyanate (B1) having a number average molecular weight of from 350 to 500 and having a low functional group imparts flexibility to the drape film and also has an effect of improving workability in forming the surface layer.

When the number average molecular weight of the HDI-modified polyisocyanate (B1) is less than 350, an odor problem occurs in the formation of the surface layer. On the other hand, when the number average molecular weight exceeds 500, the viscosity becomes high, and the productivity at the time of forming a surface layer is lowered.

The average functional group number (f1) of the HDI-modified polyisocyanate (B1) is 2 or less and f1 is less than 3. When the average functional group number (f1) is less than 2, the bridging effect is insufficient and the physical properties of the coating film are lowered. On the other hand, when the average functional group number (f1) is 3 or more, the flexibility of the coating film is lowered.

Specific examples of HDI-modified polyisocyanate (B1) are low molecular alcohols (molecular weight 62 to 164) and HDI 1:2 (Morby) additives, low molecular monols (molecular weight 32 to 164) and HDI 1:2 (Morby) an allophanate modified body or the like. Among the foregoing, an allophanate modified body having a low viscosity low molecular monol and a HDI of 1:2 (Morby) is preferred.

Low molecular monohydric alcohols are, for example, methanol, ethanol, propanol (including various anisotropy), butanol (including various anisotropy), pentanol (including various anisotropy), hexanol (including various anisotropes), heptanol (including Saturated aliphatic monoalcohols such as various anisotropic substances, octanol (including various anisotropy), sterol (including various anisotropy), and unsaturated aliphatic monoalcohol having 2 to 9 carbon atoms. The above-mentioned preferred low molecular monol is isopropanol having a small molecular weight and a high hiding effect.

An example of a specific production method of the allophanate-modified body (B1) of HDI is an HDI and a single of 2 times the molar equivalent or more with respect to the hydroxyl group in the presence of an allophanate catalyst. After the alcohol is subjected to the allophanation reaction, a catalyst poison is added to remove unreacted HDI.

The HDI isocyanurate modified polyisocyanate (B2) imparts an improvement in the physical properties of the surface layer formed after hardening.

The average functional group number (f2) of the HDI isocyanurate-modified polyisocyanate (B2) is f2 or more. When the average functional group number (f2) is less than 3, there is a problem that the hysteresis loss is lowered. Further, the upper limit of the average functional group number (f2) is not particularly limited, and from the viewpoint of workability, it is preferably 10 or less.

The HDI isocyanurate-modified polyisocyanate (B2) is obtained by removing an unreacted HDI by reacting a portion of the HDI or HDI urethane polymer with an isocyanurate reaction. Here, the partial urethane polymer of HDI means that the HDI and the low molecular alcohol are reacted with respect to the excess amount of the hydroxyl group, and the preparation of the mole is preferably HDI: low molecular alcohol = 5 :1 to 100:1. Further, the low molecular weight alcohol is preferably 1,3-butanediol in consideration of the polyisocyanate compatibility obtained and the desired isocyanate content of the polyisocyanate.

The compounding ratio of the HDI-modified polyisocyanate (B1) to the HDI isocyanurate-modified polyisocyanate (B2) is a mass ratio of (B1):(B2)=50:50 to 95:5. When the ratio of (B1) is less than 50%, there is a problem that the surface layer formed after hardening is insufficient in flexibility. On the other hand, when the ratio of (B1) exceeds 95 (%), there is a problem that the hysteresis loss is lowered.

The hardener (B) may be a polyisocyanate other than the HDI-modified polyisocyanate (B1) and the HDI isocyanurate-modified polyisocyanate (B2), as the case requires. Specifically, it is diphenylmethane diisocyanate (including various anisotropic substances), tolylene diisocyanate (including various anisotropy), xylene diisocyanate (including various anisotropy), tetramethyl dimethyl diisocyanate (including various Aliphatic), phenyl diisocyanate (including various anisotropic), such as aromatic diisocyanate, tetramethylene diisocyanate, 3-methyl-1,5-pentane diisocyanate, trimethylglycine diisocyanate, etc. Isocyanate, isophorone diisocyanate, hydrogen addition tolylene diisocyanate, hydrogen addition xylene diisocyanate, hydrogen addition of alicyclic diisocyanate such as diphenylmethane diisocyanate, and the like. Further, for example, the aforementioned polymer or carbamic acid, urea compound, allophanate, bis-uride, carbodiimide, ureton amide, isocyanate dimer, isocyanuric acid An esterified product or the like is even a mixture of two or more of the foregoing.

The isocyanate content of the hardener (B) is preferably from 10% by mass to 25% by mass, more preferably from 13% by mass to 22% by mass. When the isocyanate content is too high, since the content of the free isocyanate is large, workability problems such as occurrence of odor may occur. Further, when the content of the isocyanate is too low, the strength and durability of the surface layer for the formed layer are insufficient due to the decrease in the bridging density.

An additive may be used in combination in either or both of the main component (A) and the curing agent (B). The additives are, for example, plasticizers, fillers, colorants, flame retardants, organic or inorganic fillers, antioxidants, ultraviolet absorbers, plasticizers, pigments, dyes, antibacterial agents, antifungal agents, and the like. The urethane resin surface layer material group formed on the enamel laminate body of the preferred embodiment described above is preferably used as a draped fabric layer of artificial leather (synthetic leather, artificial leather). surface layer. Further, the present invention is not limited to the above, and a coating agent such as a permeation waterproofing material may be used.

Next, the artificial leather of the preferred embodiment is a surface layer and a weiweiwei layer formed by using the urethane resin surface layer material formed on the fibrous laminate of the above preferred embodiment.

In a preferred embodiment of the method for producing an artificial leather, a solution (hereinafter referred to as a compounding liquid) which is combined with the urethane resin surface layer material formed on the above-mentioned fibrous laminate is applied to a release support, and is once hardened. Thereafter, the method of bonding to the bismuth cloth to perform secondary hardening, and then removing the release support thereafter. Further, another preferred embodiment of the production method is a method in which a compounding liquid is directly applied to a bismuth cloth and heat-hardened.

In a preferred embodiment of the above production method, when a compounding liquid is formed on the release support, it may be applied by a usual coating method such as a doctor roll, and after one-time hardening, it may be bonded to the fabric. Secondary hardening is carried out, after which the release support is removed.

On the other hand, in other preferred embodiments of the manufacturing method, when the compounding liquid is directly applied to the bismuth cloth, the squeegee coating, the ring-bar coating, the squeegee coating, the reverse roll coating, and the calendering may be used. Coating method such as machine coating method. In this case, after the coating agent is applied onto the surface of the synthetic leather, it is heat-hardened to form a coating film.

When artificial leather is produced by using 繊维布帛 (繊维层层), the surface of the surface layer is used for the surface side of the final product as an example. However, the surface of the surface layer may be used under the same manufacturing method. A permeated waterproof material is produced by the inner side (inner side).

The release support is, for example, a release paper or a polyester film.

Further, the above-mentioned weiweibu 帛 is, for example, a natural weiwei, a synthetic weiwei. Specific examples are cotton, short fibers, polyester, nylon, propylene, and a mixture of two or more of the foregoing. Also, the weiweibu 帛 form is, for example, a woven fabric, a knitted fabric, a non-woven fabric, a pile fabric, or the like. Further, the fluorene oxime may be a laminated substrate having a porous film such as a urethane resin on one side. Further, the above-mentioned weiweibu can also be subjected to water repellent treatment such as enamel resin or fluororesin.

The surface film thickness formed using the urethane resin surface material group is preferably from 1 μm to 200 μm, more preferably from 5 μm to 100 μm.

The compounding liquid (preparation liquid) obtained by blending the polyurethane resin surface layer material formed on the fiber laminate is preferably a compound having a hydroxyl group and an isocyanate group as a hydroxyl group/isocyanate group. 90/100 to 110/100. When the molar ratio of the hydroxyl group to the isocyanate group is outside the aforementioned ratio range, the strength and durability of the coating layer become insufficient.

The heating temperature during hardening is preferably from 50 degrees Celsius to 150 degrees Celsius. The heating time is preferably from 2 minutes to 2 hours. If the temperature is too low or the time is too short, hardening will be insufficient. On the other hand, in the case where the temperature is too high or the time is too long, the coating film and the substrate may be subjected to unnecessary heat history.

When the main agent (A)/hardener (B) is blended, the purpose is to increase the hardening process or increase the reaction rate, and a catalyst may be added. The catalyst is a carbamate reaction catalyst, such as triethylamine, tetramethyl propylene diamine, tetramethylhexene diamine, toluene diamine, etc. A metal catalyst represented by a third-stage amine catalyst or a tin-based catalyst such as stannous octoate, stannous octylate or dibutyltin lauric acid. The above catalysts may be used singly or in combination.

The artificial leather (synthetic leather or artificial leather) of the preferred embodiment produced by using the urethane resin surface material group formed on the enamel laminate body of the preferred embodiment is useful for clothing, shoes, leather bags, bags, etc. of.

[Examples]

The invention is described in more detail below by way of examples, but the invention is not limited thereto. In the examples and comparative examples, "%" indicates "% by mass", and "part" indicates unit mass.

[Manufacture of HDI modified polyisocyanate]

Manufacturing example 1

Capacity of agitator, thermometer, cooler, and nitrogen gas introduction tube: 950 g of HDI and 50 g of isopropyl alcohol were prepared in a 1 liter reactor, and a carbamate reaction was carried out at 90 ° C for 2 hours. The reaction product was analyzed in a Fourier transform infrared spectrometer (FT-IR) to judge that the hydroxyl group had disappeared. Next, 0.2 g of zirconium 2-ethylhexanoate was prepared and reacted at 90 ° C for 3 hours. The reaction product was analyzed in a Fourier transform infrared spectrometer and a carbon 13 nuclear magnetic resonance spectrometer ( ¹³ C-NMR) to judge that the carbamate group had disappeared. Next, 0.1 g of phosphoric acid was prepared, and the reaction was stopped at 50 ° C for 1 hour. The isocyanate content of the reaction product after stopping the reaction was 42.1%. The reaction product was subjected to thin film distillation at 130 ° C and 0.04 kPa (kPa) to remove free HDI to obtain an isocyanate content of 19.4% and a 25 degree Celsius viscosity of 1 million Pascals (mPa ‧ s). The polyisocyanate P-1 having a free HDI content of 0.1% and a color number of 10 melted hue (APHA). P-1 was analyzed in a Fourier transform infrared spectrometer and a carbon 13 nuclear magnetic resonance apparatus, and it was confirmed that no carbamate group was present, and the presence of allophanate groups was confirmed. Further, the isocyanate dimer group and the isocyanurate group are in a degree to be recognized. The P-1 number average molecular weight was determined to be 433, and the number average functional group and the isocyanate content were calculated to be 2.0.

Manufacturing Example 2

Capacity of agitator, thermometer, cooler, and nitrogen gas introduction tube: 600 parts of HDI, 5 parts of 1,3-butanediol, and 0.1 parts of potassium citrate as a catalyst were added to a 1 liter reactor as an auxiliary catalyst. In the 0.6 part of phenol, the air in the flask was replaced with nitrogen, and the mixture was stirred and heated until the reaction temperature was 70 ° C. The reaction was carried out at the same temperature for 4 hours. To the reaction liquid, 0.2 part of phosphoric acid as a stopper was added, and after stirring at the reaction temperature for 1 hour, the reaction product was subjected to thin film distillation at 130 ° C and 0.04 kPa to remove free HDI to obtain an isocyanate. The polyisocyanate P-2 having a content of 20.8%, a 25 degree Celsius viscosity of 25 million Pascals, a free HDI content of 0.3%, and a color number of 20 melted hue. P-2 was analyzed in a Fourier transform infrared spectrometer and a carbon 13 nuclear magnetic resonance spectrometer to confirm the presence of an isocyanurate group. Further, the allophanate group and the isocyanate dimer group are traceable to the extent that they can be recognized. The average molecular weight of the P-2 number was determined to be 747, and the average number of functional groups calculated from the number average molecular weight and the isocyanate content was 3.7.

[Down film evaluation]

Examples 1 to 9 and Comparative Examples 1 to 4

Under the combination of the polyurethane resin surface material group (main agent and hardener) shown in Tables 1 and 2, it will be heated at 60 ° C. ‧ Dissolved main agent and room temperature hardener with isocyanate group and hydrogen The oxygen equivalent method was applied to a release paper by a percolator to a thickness of 100 μm, and after heating at 60 ° C for 30 minutes, it was heated at 120 ° C for 1 hour to harden. Further, the mixing ratio of the main agent to the hardener is an isocyanate group and a hydroxyl group in terms of equivalent weight. Thereafter, the mixture was allowed to stand at room temperature for 24 hours to obtain a film (surface layer) of each of the examples and the comparative examples. Thereafter, various physical properties of the obtained film were evaluated.

The physical property evaluation is a film obtained by adjusting the product obtained under the above-mentioned manufacturing conditions to 300 mm × 300 mm as a sample, and then evaluation of the following evaluation items.

The results are shown in Tables 1 and 2.

In Tables 1 and 2, the components indicated by the schematic symbols are the following.

○ PCD-1000: PCD obtained by reacting diethyl carbonate with 1,6-HD, number average molecular weight = 1000

○ PCD-2000: PCD obtained by reacting diethyl carbonate with 1,6-HD, number average molecular weight = 2000

○ PCD-3000: PCD obtained by reacting diethyl carbonate with 1,6-HD, number average molecular weight = 3000

Physical property assessment test method

Tensile properties (each modulus, strength at break, stretch at break)

A film sample was punched through a dumbbell dumbbell No. 4 and measured in accordance with JIS K7311. The stretching speed was 200 mm/min and the measurement temperature was 23 degrees Celsius.

Hysteresis loss

A film sample was punched through a dumbbell cutter No. 4 at a drawing speed of 200 mm/min, a measurement temperature of 23 degrees Celsius, and stretching to 300% of the length, after which the load weight was measured.

As shown in Tables 1 and 2, the film (film) formed in the polyurethane resin surface material group of the examples was better in balance between strength and flexibility. On the other hand, Comparative Examples 1 and 3 lacked flexibility and were small in strength, and were thin films having no physical properties. In Comparative Examples 2 and 4, the strength was insufficient, the hysteresis loss was large, and the elasticity was lacking. Further, when all of the films of the examples and the comparative examples were produced, no matter which one was odorless, workability was good.

[Manufacture of synthetic leather]

Example 10

Synthetic leather was produced in the following order.

1) Under the combination of Example 3, it will be heated at 60 ° C. ‧ Dissolved main agent and room temperature hardener are mixed with isocyanate group and hydroxyl equivalent, and added as main agent/hardener mixture The catalyst was dioctyltin lauric acid 300 ppm, and the main component, the hardener, and the catalyst were uniformly mixed, and defoamed under reduced pressure.

2) This mixed solution was then applied to a release paper to a thickness of 15 μm and heated at 120 ° C for 5 minutes.

3) Thereafter, on the aforementioned structure, the polyester taffeta as a base fabric was heavily pressed.

4) After 48 hours of aging at 50 to 60 degrees Celsius, the release paper was peeled off to obtain a synthetic leather.

The resulting synthetic leather is soft and well wound. In addition, there is no smell or the like in production, but it is a substance that cares for productivity and the environment.

Example 11

Synthetic leather was produced in the following order.

1) Under the combination of Example 3, it will be heated at 60 ° C. ‧ Dissolved main agent and room temperature hardener are mixed with isocyanate group and hydroxyl equivalent, and added as main agent/hardener mixture The catalyst was dioctyltin lauric acid 300 ppm, and the main component, the hardener, and the catalyst were uniformly mixed, and defoamed under reduced pressure.

2) This compounding liquid was then used as a base fabric, and coated on polyester taffeta having a thickness of 15 μm on a polyester taffeta by a percolator.

3) Heating at 120 ° C for 5 minutes, followed by aging at 50 to 60 ° C for 48 hours to obtain a synthetic leather.

The resulting synthetic leather is soft and well wound. In addition, there is no smell or the like in production, but it is a substance that cares for productivity and the environment.

[Manufacture of artificial leather]

Example 12

Artificial leather was manufactured in the following order.

1) Under the combination of Example 3, it will be heated at 60 ° C. ‧ Dissolved main agent and room temperature hardener are mixed with isocyanate group and hydroxyl equivalent, and added as main agent/hardener mixture The catalyst was dioctyltin lauric acid 300 ppm, and the main component, the hardener, and the catalyst were uniformly mixed, and defoamed under reduced pressure.

2) This complex solution was then applied to a release paper having a thickness of 15 μm and heated at 120 ° C for 5 minutes.

3) Thereafter, on the foregoing structure, a three-dimensionally entangled nonwoven fabric made of polyester was pressed.

4) After 48 hours of aging at 50 to 60 degrees Celsius, the release paper was peeled off to obtain artificial leather.

The resulting artificial leather is soft and well wound. In addition, there is no smell or the like in production, but it is a substance that cares for productivity and the environment.

Example 13

Artificial leather was manufactured in the following order.

1) Under the combination of Example 3, it will be heated at 60 ° C. ‧ Dissolved main agent and room temperature hardener are mixed with isocyanate group and hydroxyl equivalent, and added as main agent/hardener mixture The catalyst was dioctyltin lauric acid 300 ppm, and the main component, the hardener, and the catalyst were uniformly mixed, and defoamed under reduced pressure.

2) This mixed solution was then applied to a release paper to a thickness of 15 μm and heated at 120 ° C for 5 minutes.

3) Heating at 120 ° C for 5 minutes, followed by aging at 50 to 60 ° C for 48 hours to obtain artificial leather.

The resulting artificial leather is soft and well wound. In addition, there is no smell or the like in production, but it is a substance that cares for productivity and the environment.

Claims (7)

A polyurethane resin surface layer material group formed on a fiber laminate, the main agent (A) composed of a polycarbonate diol obtained by reacting 1,6-hexanediol and a low molecular carbonate, and a number average a hexamethylene diisocyanate modified polyisocyanate (B1) having a molecular weight of 350 to 500 and an average functional group number (f1) of 2 or less and less than or equal to f1 of less than 3, and a isocyanuric acid having an average functional group number (f2) of hexamethylene diisocyanate having a f2 of 3 or more The hardener (B) composed of the acid ester-modified polyisocyanate (B2) is composed, and the mass ratio of (B1) and (B2) is (B1): (B2) = 50:50 to 95:5. The urethane resin surface layer material group formed on the fiber laminate according to claim 1, wherein the hexamethylene diisocyanate modified polyisocyanate (B1) comprises a reaction of a low molecular monool with hexamethylene diisocyanate. Allophanate modified isocyanate. An artificial leather comprising a surface layer formed of a urethane resin surface layer material formed on a fibrous laminate as described in claim 1 or 2, and a weiweiwei layer covered by the surface layer. A method for producing an artificial leather, which comprises applying a solution of a polyurethane resin surface layer material group formed on a fibrous laminate as described in the first or second aspect of the patent application to a release support, after one hardening, pasting The secondary hardening is carried out in combination with the weiweibu, and then the release support is removed. A method for producing an artificial leather, which is directly coated with a solution of a urethane resin surface layer material formed on a fibrous laminate as described in claim 1 or 2, and heat-cured. The method for producing an artificial leather according to claim 5, The molar ratio of the hydroxyl group to the isocyanate group in the solution of the urethane resin surface layer material group formed on the fiber laminate is hydroxyl group/isocyanate group = 90/100 to 110/100. The artificial leather manufacturing method according to claim 6, wherein the molar ratio of the hydroxyl group to the isocyanate group in the solution of the polyurethane resin surface material group formed on the fiber laminate is hydroxyl/isocyanate Base = 90/100 to 110/100.