TW202144447A - Carbamate resin composition and synthetic leather characterized by comprising a carbamate resin that uses a polyol containing a polycarbonate polyol, a chain extender other than the polyol and a polyisocyanate as essential raw materials - Google Patents

Abstract

The present invention provides a carbamate resin composition, which is a carbamate resin composition containing a carbamate resin (X). The carbamate resin (X) uses a polyol (A) containing a polycarbonate polyol (a1), a chain extender (B) other than the polyol (A) and a polyisocyanate (C) as essential raw materials. The polyisocyanate (C) contains an aliphatic polyisocyanate (c1) and an aromatic polyisocyanate (c2); and the content of the aliphatic polyisocyanate (c1) is within the range of 1-45% by mass of the polyisocyanate (C). It is preferable that the aliphatic polyisocyanate (c1) is composed of one or more compounds selected from the group consisting of hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated xylylene diisocyanate and pentamethylene diisocyanate.

Description

Urethane resin composition, and synthetic leather

The present invention relates to a urethane resin composition and synthetic leather.

Urethane resins are widely used in various fields such as synthetic leather and sheeting for molding, and in particular, when used in long-term components such as synthetic leather for vehicle interiors, more stringent requirements are required. High durability.

There are many evaluation items of the said durability, and heat resistance, heat-and-moisture resistance, light resistance, chemical resistance, abrasion resistance, etc. are mentioned (for example, refer patent document 1). Among them, the current situation in particular in recent years is that the use in cold regions is expected, and the required level of flexibility at low temperatures is also increasing year by year. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2012-1693

[The problem to be solved by the invention]

The problem to be solved by the present invention is to provide a urethane resin composition excellent in low-temperature flexibility and heat resistance. [means to solve the problem]

The present invention provides a urethane resin composition characterized in that it is a urethane resin composition containing a urethane resin (X), and the urethane resin (X) The polyol (A) containing the polycarbonate polyol (a1), the chain extender (B) other than the polyol (A), and the polyisocyanate (C) are essential raw materials, and the polyisocyanate (C) contains In the aliphatic polyisocyanate (c1) and the aromatic polyisocyanate (c2), the content of the aliphatic polyisocyanate (c1) is in the range of 1 to 45 mass % in the polyisocyanate (C).

Moreover, this invention provides the synthetic leather which has the layer formed of the said urethane resin composition, It is characterized by the above-mentioned. [Effect of invention]

The urethane resin composition of the present invention is excellent in low temperature flexibility and heat resistance.

Accordingly, the urethane resin composition of the present invention can be suitably used as a material used in the manufacture of synthetic leather, clothing, backing pads, polishing pads, etc., and can be suitably used as a material of synthetic leather. use.

The urethane resin composition of the present invention contains a urethane resin (X) composed of a polyol (A) comprising a polycarbonate polyol (a1), A chain extender (B) other than the polyol (A) and a polyisocyanate (C) are essential raw materials, and the polyisocyanate (C) contains an aliphatic polyisocyanate (c1) and an aromatic polyisocyanate (c2), the aliphatic The content of the family polyisocyanate (c1) is in the range of 1 to 45 mass % in the polyisocyanate (C).

The aforementioned polycarbonate polyol (a1) is an essential component for obtaining excellent heat resistance. However, since the polycarbonate polyol (a1) has a rigid structure, it is considered that it is difficult to bend, and the use of the polycarbonate polyol is difficult due to the increase in the level of this requirement in recent years. However, the use of polycarbonate polyols is necessary in order to guarantee excellent heat resistance, while other components are subject to improvement review.

As the aforementioned polycarbonate polyol (a1), for example, propylene glycol, butanediol, pentanediol, hexanediol, decanediol, caprolactone, cyclohexanedimethanol, 3-methyl-1, Polycarbonate polyols such as 5-pentanediol, neopentyl glycol, isosorbide, etc. as raw materials. These raw materials are used as raw materials having a hydroxyl group, and may be used alone or in combination of two or more. Among these, from the viewpoint of being able to further improve the balance between low-temperature flexibility and heat resistance, it is preferable to use those selected from the group consisting of those using hexanediol as a raw material, those using butanediol and hexanediol as raw materials, One or more polycarbonate polyols of the group that uses butanediol and decanediol as raw materials, and pentanediol and hexanediol as raw materials.

Specifically, the above-mentioned polycarbonate polyol (a1) can be used by a known method by reacting the above-mentioned raw material, carbonate and/or phosgene.

As the aforementioned carbonate, for example, dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylidene carbonate, propylidene carbonate, etc. can be used. These compounds may be used alone or in combination of two or more.

The number average molecular weight of the aforementioned polycarbonate polyol (a1) is preferably in the range of 500 to 10,000, more preferably in the range of 700 to 4,000, from the viewpoint of obtaining more excellent heat resistance and mechanical strength. In addition, the number average molecular weight of the said polycarbonate polyol (a1) shows the value measured by the gel permeation chromatography (GPC) method.

The content of the polycarbonate polyol (a1) is preferably 50% by mass or more, more preferably 70% by mass in the polyol (A) from the viewpoint that the balance between low-temperature flexibility and heat resistance can be further improved. above.

As the polyol (A), other polyols may be used in combination in addition to the polycarbonate polyol (a1).

As the aforementioned other polyols, for example, polyether polyols, polyester polyols, polyacrylic polyols, and the like can be used. Among these, when low-temperature flexibility is more strongly required, polyether polyol is preferably used, and polytetramethylene glycol is more preferably used.

As a number average molecular weight of the said other polyol, the range of 500-100,000 is mentioned, for example. In addition, the number average molecular weight of the said other polyol means the value measured by the gel permeation chromatography (GPC) method.

As a usage-amount of the said polyol (A), the range of 50-95 mass % in the sum total of raw materials which comprise the said urethane resin (X) is mentioned, for example, Preferably it is the range of 70-90 mass %.

、2-甲基哌

、2,5-二甲基哌

、異佛酮二胺、4,4’-二環己基甲烷二胺、3,3’-二甲基-4,4’-二環己基甲烷二胺、1,2-環己二胺、1,4-環己二胺、胺基乙基乙醇胺、聯胺、二伸乙三胺、三伸乙四胺等之具有胺基之鏈伸長劑。該等之鏈伸長劑係可單獨使用，也可合併使用2種以上。該等之中，基於可獲得更為優異之耐熱性的觀點，較佳為使用乙二醇。The above-mentioned chain extender (B) is other than the above-mentioned polyhydric alcohol (A), for example, means that the molecular weight is 50 or more and less than 500, for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1, Chain extenders with hydroxyl groups such as 3-propanediol, 1,3-butanediol, 1,4-butanediol, hexanediol, trimethylolpropane, glycerin, etc.; ethylenediamine, 1,2-propanediol Amine, 1,6-Hexanediamine, Piper

, 2-methylpiperidine

, 2,5-Dimethylpiperidine

, isophorone diamine, 4,4'-dicyclohexylmethanediamine, 3,3'-dimethyl-4,4'-dicyclohexylmethanediamine, 1,2-cyclohexanediamine, 1 , 4-cyclohexanediamine, aminoethylethanolamine, hydrazine, diethylenetriamine, triethylenetetramine and other chain extenders with amine groups. These chain extenders may be used alone or in combination of two or more. Among these, it is preferable to use ethylene glycol from the viewpoint of obtaining more excellent heat resistance.

As the usage-amount of the said chain extender (B), the range of 0.1-30 mass % in the total of the raw materials which comprise the said urethane resin (X) is mentioned, for example, based on the fact that more excellent heat resistance can be obtained. From a viewpoint, the range of 1-20 mass parts is preferable.

The aforementioned polyisocyanate (C) must contain an aliphatic polyisocyanate (c1) and an aromatic polyisocyanate (c2) in order to obtain excellent low-temperature flexibility, and the content of the aforementioned aliphatic polyisocyanate (c1) is based on the polyisocyanate. In the isocyanate (C), it is the range of 1-45 mass %.

The above-mentioned aromatic polyisocyanate (c2) has high heat resistance, but has a high glass transition temperature (Tg) during urethane formation, which is disadvantageous for low-temperature properties. On the other hand, in general, the aforementioned aliphatic polyisocyanate (c1) has a low glass transition temperature and poor heat resistance, but is advantageous for low-temperature flexibility. In the present invention, by using both in a specific range, even if the aforementioned polycarbonate polyol (a1) is used, both heat resistance and low-temperature flexibility can be achieved at a high level.

As content rate of the said aliphatic polyisocyanate (c1), the range of 5-40 mass % in polyisocyanate (C) is preferable from a viewpoint that the balance of heat resistance and low temperature flexibility can be improved more.

As said aliphatic polyisocyanate (c1), for example, hexamethylene diisocyanate, pentamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate can be used Isocyanate, hydrogenated stubble diisocyanate, norbornene diisocyanate, etc. These polyisocyanates may be used alone or in combination of two or more. Among these, from the viewpoint of being able to further improve the balance of heat resistance and low-temperature flexibility, it is preferable to use a compound selected from the group consisting of hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated ethylene diisocyanate, and pentamethylene diisocyanate. One or more kinds of polyisocyanates in the group of methyl diisocyanate are more preferably hexamethylene diisocyanate or isophorone diisocyanate.

As the above-mentioned aromatic polyisocyanate (c2), for example, phenylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, stubbene diisocyanate, naphthylene diisocyanate, polymethylene polyphenylene polyisocyanate can be used. Isocyanates, carbodiimide diphenylmethane polyisocyanates, etc. These polyisocyanates may be used alone or in combination of two or more. Among these, it is preferable to use diphenylmethane diisocyanate from the viewpoint that the balance of heat resistance and low-temperature flexibility can be further improved.

As a usage-amount of the said polyisocyanate (C), the range of 5-50 mass % in the sum total of the raw material which comprises the said urethane resin (X) is mentioned, for example.

As a manufacturing method of the said urethane resin (X), the said polyol (A), the said chain extender (B), and the said polyisocyanate (C) are all fed, for example, by feeding the said polyol (A) all at once, and carrying out In the method of producing by reaction, the reaction system is preferably performed, for example, at a temperature of 30 to 100° C. for 3 to 10 hours. In addition, the said reaction system can be performed in the solvent mentioned later.

The total molar ratio of the hydroxyl group contained in the polyol (A) and the hydroxyl group or amino group contained in the chain extender (B) and the molar ratio of the isocyanate group contained in the polyisocyanate (C) [( Isocyanate group)/(hydroxyl group and amine group)], preferably in the range of 0.6-2, more preferably in the range of 0.8-1.2.

The number average molecular weight of the urethane resin (X) obtained by the above method is preferably in the range of 5,000 to 1,000,000, more preferably 10,000 to 500,000 range. In addition, the number average molecular weight of the said urethane resin (X) shows the value measured by the gel permeation chromatography (GPC) method.

The said urethane resin composition contains the said urethane resin (X) as an essential component, but may contain other components as needed.

As the aforementioned other components, for example, solvents, pigments, flame retardants, plasticizers, softeners, stabilizers, waxes, antifoaming agents, dispersing agents, penetrants, surfactants, fillers, antifungal agents, and antibacterial agents can be used. , UV absorbers, antioxidants, weather stabilizers, optical brighteners, anti-aging agents, tackifiers, etc. These components may be used alone or in combination of two or more.

As the aforementioned solvent, for example, water, N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, methyl ethyl ketone, methyl Ketone solvents such as n-propyl ketone, acetone, methyl isobutyl ketone, etc.; methyl formate, ethyl formate, propyl formate, methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate , ester solvents such as isobutyl acetate and tertiary butyl acetate; alcohol solvents such as methanol, ethanol, isopropanol, butanol, etc. These solvent systems may be used alone or in combination of two or more.

As content of the said solvent, from a viewpoint of workability|operativity and viscosity, it is preferable that it is the range of 10-90 mass % in a urethane resin composition.

As described above, the urethane resin composition of the present invention is excellent in low-temperature flexibility and heat resistance.

Accordingly, the urethane resin composition of the present invention can be suitably used as a material used in the manufacture of synthetic leather, clothing, backing pads, polishing pads, etc., and can be suitably used as a material of synthetic leather. use.

Next, the synthetic leather using the said urethane resin composition is demonstrated.

The aforementioned synthetic leather has at least a layer formed of a base material and the aforementioned urethane resin composition.

As the aforementioned base material, for example, a fibrous base material including a nonwoven fabric, a woven fabric, a woven fabric, and the like; a resin film, and the like can be used. As the fibrous base material, for example, chemical fibers such as polyester fibers, nylon fibers, acrylic fibers, polyurethane fibers, acetate fibers, rayon fibers, and polylactic acid fibers can be used; cotton, hemp, etc. , silk, wool, blended fibers of these, etc.

As the resin film, for example, a polyethylene terephthalate film, a polycarbonate film, an acrylic resin film, a COP (cycloolefin polymer) film, a TAC (triacetyl cellulose) film, and the like can be used.

The surface of the aforementioned substrate can be subjected to electrical processing, mold release processing, water repellent processing, water absorption processing, antibacterial and deodorant processing, bacteriostatic processing, and ultraviolet shielding processing as required.

As a method of forming a layer from the above-mentioned urethane resin composition, for example, applying the above-mentioned urethane resin by a coater, a bar coater, a knife coater, a T-die coater, a roll coater and the like can be mentioned. The composition is applied, for example, a method of drying at a temperature of 50 to 140° C. for 30 seconds to 10 minutes.

The thickness of the layer formed from the aforementioned urethane resin composition can be appropriately determined according to the intended use, and is, for example, in the range of 0.001 to 10 mm.

Since the layer formed from the urethane resin composition is excellent in heat resistance and low-temperature flexibility, it is preferably used as a skin layer and/or surface-treated layer of synthetic leather, more preferably a skin layer. [Example]

Hereinafter, the present invention will be described in more detail using examples.

[Example 1] 350 parts by mass of polycarbonate diol (using 1,6-hexanediol as a raw material, number average molecular weight: 2,000, hereinafter abbreviated as "PC1") was added to a nitrogen-passaged room equipped with a stirrer, a reflux cooling tube and a thermometer. In place of the 4-necked flask, dehydration was carried out at 120 to 130° C. under a reduced pressure of 0.095 MPa. After dehydration, 650 parts by mass of N,N-dimethylformamide (hereinafter abbreviated as "DMF") and 11 parts by mass of ethylene glycol (hereinafter abbreviated as "EG") were added and cooled to 30°C Mix well. Then, 21 parts by mass of hexamethylene diisocyanate (hereinafter abbreviated as "HDI") and 54 parts by mass of 4,4'-diphenylmethane diisocyanate (hereinafter abbreviated as "MDI") were added, and the mixture was heated to 80°C. After 2 hours of lower mixing, 0.2 parts by mass of stannous octoate was added, and the mixture was mixed at 100° C. for 8 hours. Next, 360 parts by mass of methyl ethyl ketone (hereinafter abbreviated as "MEK"), 2 parts by mass of methanol, and 2 parts by mass of antioxidant were added while cooling to 70° C., and mixed to obtain carbamic acid Ester resin composition.

[Example 2] 350 mass parts of PC1 were added to the nitrogen-substituted 4-neck flask equipped with a stirrer, a reflux cooling tube, and a thermometer, and dehydration was carried out at 120-130 degreeC under the pressure reduction degree of 0.095MPa. After dehydration, 660 parts by mass of DMF was added while cooling to 70° C., and mixed well. Then, 14 parts by mass of HDI and 0.2 parts by mass of stannous octoate were added, and after mixing at 100° C. for 2 hours, 11 parts by mass of EG was added and mixed. Next, after adjusting to 50°C, 64 parts by mass of MDI was added, and after mixing at 80°C for 8 hours, 370 parts by mass of MEK, 2 parts by mass of methanol, and 2 parts by mass of antioxidant were added and mixed to obtain amine Carbamate resin composition.

[Example 3] 300 mass parts of PC1 were added to the nitrogen-substituted 4-neck flask equipped with a stirrer, a reflux cooling tube, and a thermometer, and dehydration was performed at 120-130 degreeC under the pressure reduction degree of 0.095MPa. After dehydration, 690 parts by mass of DMF and 27 parts by mass of EG were added, and the mixture was sufficiently mixed while cooling to 30°C. Then, 24 parts by mass of HDI and 109 parts by mass of MDI were added, and after mixing at 80°C for 2 hours, 0.2 parts by mass of stannous octoate was added, and the mixture was mixed at 100°C for 8 hours. Next, 380 parts by mass of DMF, 2 parts by mass of methanol, and 2 parts by mass of antioxidant were added while cooling to 70° C., and mixed to obtain a urethane resin composition.

[Example 4] 240 parts by mass of PC1 and 60 parts by mass of polytetramethylene glycol (number average molecular weight: 2000, hereinafter abbreviated as "PTMG") were added to a 4-neck flask substituted with nitrogen, which was equipped with a stirrer, a reflux cooling tube and a thermometer, Dehydration was carried out at 120 to 130° C. under a reduced pressure of 0.095 MPa. After dehydration, 760 parts by mass of DMF was added while cooling to 70° C., and mixed well. Then, 18 parts by mass of HDI and 0.2 parts by mass of stannous octoate were added, and after mixing at 100° C. for 2 hours, 36 parts by mass of EG was added and mixed. Next, after adjusting to 50°C, 154 parts by mass of MDI was added, and after mixing at 80°C for 8 hours, 420 parts by mass of MEK, 2 parts by mass of methanol, and 2 parts by mass of antioxidant were added and mixed to obtain amine Carbamate resin composition.

[Example 5] 165 parts by mass of PC1 and 135 parts by mass of PTMG were added to a nitrogen-substituted 4-neck flask equipped with a stirrer, a reflux cooling tube, and a thermometer, and dehydration was carried out at 120-130° C. under a reduced pressure of 0.095 MPa. After dehydration, 700 parts by mass of DMF and 27 parts by mass of EG were added, and the mixture was sufficiently mixed while cooling to 30°C. Then, 24 parts by mass of isophorone diisocyanate (hereinafter abbreviated as "IPDI") and 118 parts by mass of MDI were added, and after mixing at 80°C for 2 hours, 0.2 parts by mass of stannous octoate was added, and the mixture was heated at 100°C. Mix for 8 hours. Next, 390 parts by mass of MEK, 2 parts by mass of methanol, and 2 parts by mass of antioxidant were added and mixed while cooling to 70° C. to obtain a urethane resin composition.

[Example 6] Add 300 parts by mass of polycarbonate diol (using 1,5-pentanediol and 1,6-hexanediol as raw materials, number average molecular weight: 2,000, hereinafter abbreviated as "PC2") to a mixer equipped with a mixer, The reflux cooling tube and the 4-neck flask of the thermometer substituted with nitrogen were dehydrated at 120-130° C. under a decompression degree of 0.095 MPa. After dehydration, 700 parts by mass of DMF was added while cooling to 70° C., and mixed well. Then, 12 parts by mass of HDI and 0.2 parts by mass of stannous octoate were added, and after mixing at 100° C. for 2 hours, 27 parts by mass of EG was added and mixed. Next, after adjusting to 50°C, 118 parts by mass of MDI was added, and after mixing at 80°C for 8 hours, 390 parts by mass of MEK, 2 parts by mass of methanol, and 2 parts by mass of antioxidant were added and mixed to obtain amine Carbamate resin composition.

[Example 7] Add 180 parts by mass of polycarbonate diol (using 1,4-butanediol and 1,6-hexanediol as raw materials, number average molecular weight: 2,000, hereinafter abbreviated as "PC3"), 120 parts by mass of PTMG was dehydrated at 120 to 130° C. under a reduced pressure of 0.095 MPa in a 4-necked flask equipped with a stirrer, a reflux cooling tube, and a thermometer substituted with nitrogen. After dehydration, 560 parts by mass of DMF and 9 parts by mass of EG were added, and the mixture was sufficiently mixed while cooling to 30°C. Then, 18 parts by mass of HDI and 46 parts by mass of MDI were added, and after mixing at 80°C for 2 hours, 0.2 parts by mass of stannous octoate was added, and the mixture was mixed at 100°C for 8 hours. Next, 310 parts by mass of DMF, 2 parts by mass of methanol, and 2 parts by mass of antioxidant were added while cooling to 70° C., and mixed to obtain a urethane resin composition.

[Example 8] Add 225 parts by mass of polycarbonate diol (using 1,4-butanediol and 1,10-decanediol as raw materials, number average molecular weight: 3,000, hereinafter abbreviated as "PC4"), 75 parts by mass of PTMG was dehydrated at 120 to 130° C. under a reduced pressure of 0.095 MPa in a 4-necked flask equipped with a stirrer, a reflux cooling tube, and a thermometer substituted with nitrogen. After dehydration, 690 parts by mass of DMF was added while cooling to 70° C., and mixed well. Then, 9 parts by mass of HDI and 0.2 parts by mass of stannous octoate were added, and after mixing at 100° C. for 2 hours, 27 parts by mass of EG was added and mixed. Next, after adjusting to 50°C, 122 parts by mass of MDI was added, and after mixing at 80°C for 8 hours, 380 parts by mass of DMF, 2 parts by mass of methanol, and 2 parts by mass of antioxidant were added and mixed to obtain amine Carbamate resin composition.

[Comparative Example 1] 300 mass parts of PC1 were added to the nitrogen-substituted 4-neck flask equipped with a stirrer, a reflux cooling tube, and a thermometer, and dehydration was performed at 120-130 degreeC under the pressure reduction degree of 0.095MPa. After dehydration, 710 parts by mass of DMF and 27 parts by mass of EG were added, and the mixture was sufficiently mixed while cooling to 30°C. Then, 145 parts by mass of MDI was added, and after mixing at 80° C. for 8 hours, 390 parts by mass of DMF, 2 parts by mass of methanol, and 2 parts by mass of antioxidant were added and mixed to obtain a urethane resin. composition.

[Comparative Example 2] 240 parts by mass of PC1 and 160 parts by mass of PTMG were added to a nitrogen-substituted 4-neck flask equipped with a stirrer, a reflux cooling tube, and a thermometer, and dehydration was carried out at 120-130° C. under a reduced pressure of 0.095 MPa. After dehydration, 740 parts by mass of DMF and 12 parts by mass of EG were added, and the mixture was sufficiently mixed while cooling to 30°C. Then, 40 parts by mass of HDI and 38 parts by mass of MDI were added, and the mixture was mixed at 80° C. for 2 hours, and then 0.2 part by mass of stannous octoate was added, and the mixture was mixed at 100° C. for 8 hours. Next, 410 parts by mass of DMF, 2 parts by mass of methanol, and 2 parts by mass of antioxidant were added and mixed while cooling to 70° C. to obtain a urethane resin composition.

[Comparative Example 3] 300 parts by mass of PTMG was added to a nitrogen-substituted 4-neck flask equipped with a stirrer, a reflux cooling tube, and a thermometer, and dehydration was carried out at 120 to 130° C. under a reduced pressure of 0.095 MPa. After dehydration, 700 parts by mass of DMF was added while cooling to 70° C., and mixed well. Then, 18 parts by mass of HDI and 0.2 parts by mass of stannous octoate were added, and after mixing at 100° C. for 2 hours, 27 parts by mass of EG was added and mixed. Next, after adjusting to 50°C, 118 parts by mass of MDI was added, and after mixing at 80°C for 8 hours, 390 parts by mass of MEK, 2 parts by mass of methanol, and 2 parts by mass of antioxidant were added and mixed to obtain amine Carbamate resin composition.

[Method for Determination of Number Average Molecular Weight] The number-average molecular weights of the polyols and the like used in Examples and Comparative Examples represent values measured by gel permeation chromatography (GPC) under the following conditions.

Measuring device: High-speed GPC device (“HLC-8220GPC” manufactured by TOSOH Co., Ltd.) Column: The following columns manufactured by TOSOH Co., Ltd. were connected in series and used. "TSKgel G5000" (7.8mmI.D.×30cm)×1 "TSKgel G4000" (7.8mmI.D.×30cm)×1 "TSKgel G3000" (7.8mmI.D.×30cm)×1 "TSKgel G2000" (7.8mmI.D.×30cm)×1 Detector: RI (differential refractometer) Column temperature: 40℃ Eluent: Tetrahydrofuran (THF) Flow rate: 1.0mL/min Injection volume: 100 μL (tetrahydrofuran solution with a sample concentration of 0.4 mass %) Standard sample: A calibration curve was prepared using the following standard polystyrene.

(standard polystyrene) "TSKgel Standard Polystyrene A-500" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene A-1000" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene A-2500" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene A-5000" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene F-1" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene F-2" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene F-4" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene F-10" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene F-20" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene F-40" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene F-80" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene F-128" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene F-288" manufactured by TOSOH Co., Ltd. "TSKgel Standard Polystyrene F-550" manufactured by TOSOH Co., Ltd.

[Evaluation method of low temperature bendability] In 100 parts by mass of the urethane resin compositions obtained in Examples and Comparative Examples, the urethane resin compositions obtained in Examples and Comparative Examples were coated on release paper so that the film thickness after drying was 30 μm, including 60 parts by mass of DMF and 20 parts by mass of DIC Co., Ltd. The blend liquid of the colorant "DAILAC L-1770S" manufactured by the company was dried at 70°C for 2 minutes, and further dried at 120°C for 2 minutes, to form a film on the release paper. Next, 100 parts by mass of urethane resin "CRISBON TA-205FT" manufactured by DIC Co., Ltd., 60 parts by mass of DMF, and 12 parts by mass of DMF were applied on the film so that the film thickness after drying was 60 μm. A mixed solution of one part of the polyisocyanate crosslinking agent "BURNOCK DN-950" manufactured by DIC Co., Ltd. and 1 part by mass of the tin catalyst "AXLE T-81E" manufactured by DIC Co., Ltd. was dried at 100°C for 1 minute. . Next, the polyester base fabric was placed and crimped with a laminator at 120° C., then aged at 40° C. for 3 days, the release paper was peeled off, and a synthetic leather was obtained. This synthetic leather was subjected to a bending test (-30°C, 100 times/min) using a deflection meter ("Deflection meter with a low temperature tank" manufactured by Yasuda Seiki Co., Ltd.) to measure the occurrence of tortoises on the surface of the synthetic leather. The number of times to crack was evaluated as follows. "A": 20,000 times or more "B": 10,000 times or more and less than 20,000 times "C": less than 10,000 times

[Measuring method of heat resistance] A blended solution containing 100 parts by mass of a polyurethane resin solution and 60 parts by mass of DMF was applied on a flat release paper so that the film thickness after drying was 30 μm, and dried at 70° C. for 2 minutes , and dried at 120° C. for 2 minutes to obtain a polyurethane resin film. Next, this polyurethane resin film was cut into a short rectangular shape with a width of 5 mm and a length of 50 mm, and a tensile tester "AUTOGRAPH AG-1" (manufactured by Shimadzu Corporation) was used between the jigs. A tensile test was carried out in an environment of a distance of 40 mm, a tensile speed of 10 mm/sec, and a temperature of 23° C., and the stress at break was measured. Next, this polyurethane resin film was stored in a dryer set at 120° C. for 400 hours. Then, the polyurethane resin film was taken out, and after returning to room temperature, it was cut into a short rectangular shape with a width of 5 mm and a length of 50 mm, and a tensile tester "AUTOGRAPH AG-1" (Shimadzu Corporation Co., Ltd.) was used. Co., Ltd.), the tensile test was carried out in an environment of 40 mm distance between jigs, 10 mm/sec tensile speed, and 23° C. temperature, and the stress at break was measured. The fracture stress retention rate was calculated from the two stresses and evaluated as follows. "A": 80% or more "B": more than 50% and less than 80% "C": less than 50%

[Table 1] Table 1 Example 1 Example 2 Example 3 Example 4 Urethane resin (X) Polyol (A) Polycarbonate Polyol (a1) type PC1 PC1 PC1 PC1 Other polyols type PTMG Chain Extender (B) EG EG EG EG Polyisocyanate (C) Aliphatic polyisocyanate (c1) HDI HDI HDI HDI Aromatic polyisocyanate (c2) MDI MDI MDI MDI (c1) Content (in polyisocyanate (C), mass %) 28 18 18 10 Evaluation of low temperature bendability A B B A Evaluation of heat resistance B B B B

[Table 2] Table 2 Example 5 Example 6 Example 7 Example 8 Urethane resin (X) Polyol (A) Polycarbonate Polyol (a1) type PC1 PC2 PC3 PC4 Other polyols type PTMG PTMG PTMG Chain Extender (B) EG EG EG EG Polyisocyanate (C) Aliphatic polyisocyanate (c1) IPDI HDI HDI HDI Aromatic polyisocyanate (c2) MDI MDI MDI MDI (c1) Content (in polyisocyanate (C), mass %) 17 9 28 7 Evaluation of low temperature bendability A A A A Evaluation of heat resistance B A B A

[table 3] table 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Urethane resin (X) Polyol (A) Polycarbonate Polyol (a1) type PC1 PC1 Other polyols type PTMG PTMG Chain Extender (B) EG EG EG Polyisocyanate (C) Aliphatic polyisocyanate (c1) HDI HDI Aromatic polyisocyanate (c2) MDI MDI MDI (c1) Content (in polyisocyanate (C), mass %) 0 51 13 Evaluation of low temperature bendability C A A Evaluation of heat resistance A C C

It was found that Examples 1 to 8, which are the urethane resin compositions of the present invention, are excellent in low-temperature flexibility and heat resistance.

On the other hand, in Comparative Example 1, the aliphatic polyisocyanate (c1) was not used, and the low-temperature flexibility was poor.

Comparative Example 2 is an aspect in which the content rate of the aliphatic polyisocyanate (c1) exceeds the range defined by the present invention, and the heat resistance is poor.

In Comparative Example 3, polytetramethylene glycol was used in place of the polycarbonate polyol (a1), and the heat resistance was poor.

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Claims (7)

A urethane resin composition, characterized in that it is a urethane resin composition containing a urethane resin (X), and the urethane resin (X) is a Polyol (A) of carbonate polyol (a1), chain extender (B) other than the polyol (A), and polyisocyanate (C) are necessary raw materials, The polyisocyanate (C) contains an aliphatic polyisocyanate (c1) and an aromatic polyisocyanate (c2), and the content of the aliphatic polyisocyanate (c1) is in the range of 1 to 45% by mass in the polyisocyanate (C) . The urethane resin composition of claim 1, wherein the aliphatic polyisocyanate (c1) is selected from the group consisting of hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated stubble diisocyanate and pentamethylene diisocyanate One or more of the group of methyl diisocyanate. The urethane resin composition according to claim 1 or 2, wherein the aromatic polyisocyanate (c2) is diphenylmethane diisocyanate. The urethane resin composition according to any one of claims 1 to 3, wherein the polycarbonate polyol (a1) is selected from the group consisting of those containing hexanediol as a raw material, butanediol and hexanediol. One or more of the group consisting of those using diol as a raw material, those using butanediol and decanediol as raw materials, and those using pentanediol and hexanediol as raw materials. The urethane resin composition according to any one of claims 1 to 4, wherein the content of the polycarbonate polyol (a1) in the polyol (A) is 40% by mass or more. The urethane resin composition according to any one of claims 1 to 5, wherein the chain extender (B) is ethylene glycol. A synthetic leather characterized by having a layer formed of the urethane resin composition according to any one of claims 1 to 6.