JP6508519B2 - Urethane resin composition and leather-like sheet - Google Patents

Description

  The present invention relates to a urethane resin composition that can be suitably used particularly for the production of a top coat layer, a skin layer, and an intermediate layer of a leather-like sheet such as synthetic leather and artificial leather.

  In the manufacturing process of leather-like sheet | seats, such as synthetic leather and an artificial leather, the film which formed the urethane-resin composition into a film is used for the purpose of a texture improvement. Particularly when the film is used as a long-term durable material such as a vehicle interior material, high durability such as heat resistance, moist heat resistance, light resistance, chemical resistance, abrasion resistance, etc. is required (for example, a patent) See literature 1).

  In addition, when a design is given to the appearance of a leather-like sheet, a method is generally adopted in which a skin is formed on a release paper having asperities (embossed) and the grain shape is transferred to the skin. It is extremely important that there is no processing problem such as repelling or floating from a release paper when applying a coating. Therefore, there is a need for a material having both processability and durability at a higher level.

JP-A-9-31862

  The problem to be solved by the present invention is to provide a urethane resin composition excellent in hydrolysis resistance, abrasion resistance, and processability.

  In the present invention, the content of the urea bond obtained by reacting the polycarbonate polyol (a1-1), the silicone polyol (a1-2), the polyisocyanate (a2), and the chain extender (a3) having an amino group is A urethane resin composition comprising a urethane resin (A) in the range of 200 to 1,100 mmol / kg and an organic solvent (B) is provided.

  The present invention also provides a leather-like sheet obtained by forming a film of the above-mentioned urethane resin composition.

  The urethane resin composition of the present invention is excellent in durability such as heat resistance, moisture heat resistance, light resistance, chemical resistance, abrasion resistance and the like, and is also excellent in processability. Therefore, the urethane resin composition of the present invention can be used as a top coat layer, a skin layer, an intermediate layer of leather-like sheets such as synthetic leathers and artificial leathers used for clothes, vehicle seats, furniture sheets, shoes, bags and the like; , Bed sheets and other medical hygiene materials; Windproof / waterproof sheets, condensation prevention sheets, etc. Sheets for building materials such as desiccants, dehumidifying agents, fragrances etc .; Agricultural sheets, various separators, packing etc. for various uses It can be used.

  Among them, the urethane resin composition of the present invention can be suitably used for the production of a top coat layer, a skin layer and an intermediate layer of a leather-like sheet such as synthetic leather and artificial leather.

  The urethane resin composition of the present invention is a urea obtained by reacting a polycarbonate polyol (a1-1), a silicone polyol (a1-2), a polyisocyanate (a2), and a chain extender (a3) having an amino group. It is a thing containing the urethane resin (A) which is the range of 200-1,100 mmol / kg of content of coupling | bonding, and the organic solvent (B).

  The polycarbonate polyol (a1-1) is an essential component for obtaining excellent hydrolysis resistance, and is obtained, for example, by reacting a carbonic ester and / or phosgene with a compound having two or more hydroxyl groups. The thing can be used.

  As said carbonate, dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, propylene carbonate etc. can be used, for example. These compounds may be used alone or in combination of two or more.

  Examples of the compound having two or more hydroxyl groups include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, and 2-methyl. 1,3-propanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,5-hexanediol, 3-methyl-1,5-pentanediol, 1,7-heptanediol 1,8-octanediol, 1,9-nonanediol, 1,8-nonanediol, 2-ethyl-2-butyl-1,3-propanediol, 1,10-decanediol, 1,12-dodecanediol , 1,4-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, trimethylolpropane Trimethylol ethane, it can be used glycerin. These compounds may be used alone or in combination of two or more. Among these, in terms of further improving chemical resistance, it is preferable to use 1,4-butanediol and / or 1,6-hexanediol.

The number average molecular weight of the polycarbonate polyol (a1-1) is preferably in the range of 500 to 5,000, and in the range of 800 to 3,000, from the viewpoint of imparting appropriate stretchability to the film. Is more preferred. In addition, the number average molecular weight of the said polycarbonate polyol (a1-1) shows the value calculated by following Formula from a hydroxyl value.
Number average molecular weight = 56100 / hydroxyl value (mg KOH / g) × average number of functional groups The hydroxyl value is defined as mg of potassium hydroxide corresponding to the hydroxyl group in 1 g of polycarbonate polyol, in accordance with JIS K 1557-1: 2007. It was measured.

  The silicone polyol (a1-2) is an essential component for obtaining excellent abrasion resistance, and represents a polysiloxane compound having two or more hydroxyl groups. As the silicone polyol (a1-2), for example, a compound represented by the following general formula (1), a compound represented by the following general formula (5), and the like can be used.

（式（１）中、Ｒ^１及びＲ^２はそれぞれ炭素原子数１〜１０のアルキル基を示し、Ｘは下記式（２）、式（３）又は式（４）に示される構造を示し、ｎは１０〜２００の整数を示す。）

(In Formula (1), R ¹ and R ² each represent an alkyl group having 1 to 10 carbon atoms, and X represents a structure represented by the following Formula (2), Formula (3) or Formula (4), n is an integer of 10 to 200.)

（式（２）中、Ｒ^１は炭素原子数１〜１０のアルキレン基を示し、Ｒ^２は炭素原子数１〜８のアルキレン基を示し、Ｒ^３は水素原子又は炭素原子数１〜１０のアルキル基を示す。）

(In the formula (2), R ¹ represents an alkylene group having 1 to 10 carbon atoms, R ² represents an alkylene group having 1 to 8 carbon atoms, and R ³ represents a hydrogen atom or 1 to 10 carbon atoms Represents an alkyl group)

（式（３）中、Ｒ^１は炭素原子数１〜８のアルキレン基を示し、Ｒ^２は水素原子又は炭素原子数１〜１０のアルキル基を示す。）

(In formula (3), R ¹ represents an alkylene group having 1 to 8 carbon atoms, and R ² represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.)

（式（４）中、Ｒ^１は炭素原子数１〜８のアルキレン基を示し、Ｒ^２は水素原子又は炭素原子数１〜１０のアルキル基を示す。）

(In formula (4), R ¹ represents an alkylene group having 1 to 8 carbon atoms, and R ² represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.)

（式（５）中、Ｒ^１及びＲ^３はそれぞれ炭素原子数１〜８のアルキレン基を示し、Ｒ^２は炭素原子数１〜１０のアルキル基を示し、ｎは１０〜２００の整数を示す。）

(In formula (5), R ¹ and R ³ each represent an alkylene group having 1 to 8 carbon atoms, R ² represents an alkyl group having 1 to 10 carbon atoms, and n represents an integer of 10 to 200 .)

  As the silicone polyol (a1-2), it is preferable to use a compound represented by the general formula (1) from the viewpoint of obtaining more excellent abrasion resistance, and in the general formula (1), X is the above It is more preferable to use a compound having a structure represented by Formula (2).

  As the silicone polyol (a1-2), for example, “KF-6001”, “KF-6002”, “KF-6003”, “X-22-176DX”, “X-22-2” manufactured by Shin-Etsu Chemical Co., Ltd. 176 GX-A, Toray Dow Corning Co., Ltd. "SF 8427" "BY16-004", JNC Co., Ltd. "Syraplane FM-4421", "Syraplane FM-4425", "Syraplane FM-DA21", " Silaplane FM-DA26 etc. can be obtained as a commercial item.

  The use amount of the silicone polyol (a1-2) is in the range of 1 to 50 parts by mass with respect to 100 parts by mass of the polycarbonate polyol (a1-1) from the viewpoint of being able to further improve the abrasion resistance. Is preferable, and the range of 5 to 40 parts by mass is more preferable.

  Other polyols may be used in combination with the urethane resin (A) as required.

  As the other polyols, for example, polyether polyols, polyester polyols, polyacrylic polyols, dimer diols, polyisoprene polyols, polybutadiene polyols, compounds having two or more of the above hydroxyl groups, etc. can be used. These polyols may be used alone or in combination of two or more.

  Examples of the polyisocyanate (a2) include aromatic polyisocyanates such as xylylene diisocyanate, phenylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate and naphthalene diisocyanate; aliphatic polyisocyanates such as hexamethylene diisocyanate and lysine diisocyanate; cyclohexane diisocyanate Aliphatic polyisocyanates such as isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, bis (isocyanatomethyl) cyclohexane and tetramethyl xylylene diisocyanate can be used. These polyisocyanates may be used alone or in combination of two or more. Among these, from the viewpoint that light resistance, mechanical strength and abrasion resistance can be further improved, it is preferable to use alicyclic polyisocyanate, and 4,4′-dicyclohexylmethane diisocyanate, isophorone diisocyanate, cyclohexane diisocyanate and bis ( It is more preferable to use one or more polyisocyanates selected from the group consisting of isocyanatomethyl) cyclohexane.

  The amount of the polyisocyanate (a2) used is preferably in the range of 5 to 100 parts by mass with respect to 100 parts by mass of the polycarbonate polyol (a1-1) from the viewpoint of mechanical strength and heat resistance. The range of 10 to 60 parts by mass is more preferable.

  Examples of the chain extender (a3) having an amino group include ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2-methylpiperazine, 2,5-dimethylpiperazine, isophoronediamine, 4,4'-Dicyclohexylmethanediamine, 3,3'-dimethyl-4,4'-dicyclohexylmethanediamine, 2,2'-dimethyl-4,4'-dicyclohexylmethanediamine, 1,2-cyclohexanediamine, 1, 4-cyclohexanediamine, 1,3-bis (aminomethyl) cyclohexane, N- (aminoethyl) ethanolamine, hydrazine, diethylenetriamine, triethylenetetramine and the like can be used. These compounds may be used alone or in combination of two or more. Among these, from the viewpoint of being able to further improve mechanical strength, heat resistance and abrasion resistance, it is preferable to use one having an alicyclic structure, and using isophorone diamine and / or 4,4'-dicyclohexylmethane diamine. Is more preferred.

  The amount of the chain extender (a3) having an amino group is 1 to 50 with respect to 100 parts by mass of the polycarbonate polyol (a1-1) from the viewpoint of achieving both excellent processability and mechanical strength. It is preferably in the range of parts by mass and more preferably in the range of 3 to 30 parts by mass.

  As a method for producing the urethane resin (A), for example, a polyol composition containing the polycarbonate polyol (a1-1) and the silicone polyol (a1-2), and the chain extender (a3) are provided. Then, a method of charging and reacting the polyisocyanate (a2); a polyol composition containing the polycarbonate polyol (a1-1) and the silicone polyol (a1-2), and reacting the polyisocyanate (a2) And a method of obtaining a urethane prepolymer having an isocyanate group and then reacting the chain extender (a3). In addition, after the urethane reaction, an alcohol such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, butanol or the like for the purpose of deactivating the remaining isocyanate group; the polyisocyanate for the purpose of deactivating the remaining amino group (A2) or monoisocyanate such as butyl isocyanate, cyclohexyl isocyanate or octadecyl isocyanate may be further added.

  As content of the urea bond of the said urethane resin (A), in order to make mechanical strength, excellent processability, heat resistance, and abrasion resistance make compatible, it is essential that it is the range of 200-1,100 mmol / kg. The range of 250 to 1,000 mmol / kg is preferable, and the range of 300 to 900 mmol / kg is more preferable. The urea bond is generated by the reaction of the amino group of the chain extender (a3) with the isocyanate group of the polyisocyanate (a2), and the content of the urea bond is the urethane resin (A). Represents the mass of the urea bond present in the above), and shows a value calculated based on the amount of the raw material used for producing the urethane resin (A).

  As content of the alicyclic structure of the said urethane resin (A), in order to make outstanding processability, chemical resistance, and abrasion resistance make compatible, it is preferable that it is the range of 1,100-2,500 mmol / kg. In addition, the alicyclic structure of the said urethane resin (A) is introduce | transduced when using what has an alicyclic structure as said polyisocyanate (a2) and said chain extender (a3), The said alicyclic resin The content of the structure represents the mass of the alicyclic structure present in the urethane resin (A), and represents a value calculated based on the amount of the raw material used for producing the urethane resin (A).

  As content of the urethane bond of the said urethane resin (A), in order to make mechanical strength, the outstanding processability, and abrasion resistance make compatible, it is preferable that it is the range of 500-1,600 mmol / kg. The urethane bond is formed by the reaction of the hydroxyl group of the polycarbonate polyol (a1-1), the silicone polyol (a1-2) and the other polyols with the isocyanate group of the polyisocyanate (a2). The content of the urethane bond represents the amount of the urethane bond present in the urethane resin (A), and the value calculated based on the amount of the raw material used for producing the urethane resin (A) Show.

  Examples of the organic solvent (B) include ketones such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, methyl ethyl ketone, methyl n-propyl ketone, acetone, methyl isobutyl ketone and the like Solvents: Esters solvents such as methyl formate, ethyl formate, propyl formate, methyl acetate, ethyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, etc. Aroma such as toluene, xylene Group solvents; methanol, ethanol, n-propyl alcohol, isopropyl alcohol, alcohol solvents such as butanol, etc. can be used. These organic solvents may be used alone or in combination of two or more.

  Among these, since the solubility to the said urethane resin (A) is high and it is easy to remove by drying with a hot air, it is preferable to use N, N- dimethylformamide. The content of the N, N-dimethylformamide is preferably 30% by mass or more, and more preferably 50% by mass or more in the organic solvent (B).

  The use amount of the organic solvent (B) is preferably in the range of 10 to 90% by mass in the urethane resin composition, and 20 to 70% by mass, from the viewpoint of workability and viscosity for handling the urethane resin composition. The range is more preferred.

  Although the urethane resin composition of this invention contains the said urethane resin (A) and the said organic solvent (B) as an essential component, you may contain another additive as needed.

  Examples of the other additives include surfactants, pigments, catalysts, flame retardants, plasticizers, softeners, stabilizers, waxes, antifoams, dispersants, penetrants, fillers, mildewproofing agents, and antimicrobial agents. UV absorbers, antioxidants, light stabilizers, fluorescent brighteners, anti-aging agents, thickeners and the like can be used. These additives may be used alone or in combination of two or more.

  Next, a method of producing a leather-like sheet by forming a film of the urethane resin composition of the present invention will be described.

  As a method of forming a film of the urethane resin composition, a method of forming a film by a dry film forming method or the like can be mentioned.

  The dry film formation is a method of coating the urethane resin composition on release paper or base cloth and drying the organic solvent (B).

  As said base fabric, the base material etc. which consist of a nonwoven fabric, a woven fabric, a knitted fabric, etc. can be used, for example. Examples of the base fabric include chemical fibers such as polyester fiber, nylon fiber, acrylic fiber, polyurethane fiber, acetate fiber, rayon fiber, polylactic acid fiber, etc .; cotton, hemp, silk, wool, mixed fiber thereof Etc can be used.

  As a method of coating the said urethane-resin composition on the said release paper and base cloth, the gravure coater method, the knife coater method, the pipe coater method, the comma coater method etc. are mentioned, for example.

  As drying after the said coating, performing for example, 1 to 60 minutes is mentioned using the dryer etc. which were adjusted to 60-180 degreeC.

  The film thickness of the urethane resin composition after drying may be appropriately determined depending on the application to be used, and is, for example, in the range of 0.001 to 10 mm.

  As a method of producing a leather-like sheet using the dry film obtained by the dry film forming method, for example, the film is preferably a known base fabric, an intermediate layer, a skin using a known adhesive. A leather-like sheet can be produced by adhering on a layer or the like.

  As mentioned above, the urethane resin composition of this invention is excellent in durability, such as heat resistance, moisture heat resistance, light resistance, chemical resistance, abrasion resistance, etc., and is excellent also in workability. Therefore, the urethane resin composition of the present invention can be used as a top coat layer, a skin layer, an intermediate layer of leather-like sheets such as synthetic leathers and artificial leathers used for clothes, vehicle seats, furniture sheets, shoes, bags and the like; , Bed sheets and other medical hygiene materials; Windproof / waterproof sheets, condensation prevention sheets, etc. Sheets for building materials such as desiccants, dehumidifying agents, fragrances etc .; Agricultural sheets, various separators, packing etc. for various uses It can be used.

  Above all, the urethane resin composition of the present invention can be suitably used for the production of the top coat layer, the skin layer and the intermediate layer of a leather-like sheet such as synthetic leather and artificial leather.

  Hereinafter, the present invention will be described in more detail by way of examples.

Example 1
350 parts by mass of poly (hexamethylene) carbonate diol (number average molecular weight; 2000, hereinafter abbreviated as "PC-1") is added to a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas inlet tube, and a thermometer. Dehydration was performed at 120 to 130 ° C. under a reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 62 parts by mass of “FM-DA 21” (number average molecular weight; 5000, hereinafter abbreviated as “SiPol-1”) manufactured by JNC Co., N, N-dimethylformamide (below 398 parts by mass of “DMF” and 239 parts by mass of ethyl acetate were added and thoroughly mixed with stirring. Thereafter, 82 parts by mass of isophorone diisocyanate (hereinafter abbreviated as "IPDI") and 0.3 parts by mass of stannous octoate are added, and reacted at 75 ° C to obtain a solution of a urethane prepolymer having an isocyanate group. I got
Subsequently, 557 mass parts of DMF and 239 mass parts of ethyl acetate are added to the solution of the said urethane prepolymer, and it cools to 30 degreeC, and it abbreviates as 4,4'- dicyclohexyl methanediamine (henceforth "hydrogenation MDA"). 36 parts by mass of (iii) was added and chain extension was carried out by stirring. Thereafter, by adding and mixing 159 parts by mass of isopropyl alcohol (hereinafter abbreviated as "IPA"), a urethane having a urea bond content of 647 mmol / kg and an alicyclic structure content of 1,344 mmol / kg A urethane resin composition containing a resin was obtained.

Example 2
350 parts by mass of PC-1 was added to a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, and a thermometer, and dehydration was performed at 120 to 130 ° C. at a degree of reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 117 parts by mass of SiPol-1, 453 parts by mass of DMF, and 272 parts by mass of ethyl acetate were added and sufficiently mixed by stirring. Thereafter, 93 parts by mass of IPDI and 0.3 parts by mass of stannous octoate were added, and reacted at 75 ° C. to obtain a solution of an urethane prepolymer having an isocyanate group.
Next, 635 parts by mass of DMF and 272 parts by mass of ethyl acetate were added to the solution of the urethane prepolymer, cooled to 30 ° C., and 44 parts by mass of hydrogenated MDA was added and stirred for chain elongation. Thereafter, 181 parts by mass of IPA was added and mixed to obtain a urethane resin composition containing a urethane resin having a urea bond content of 694 mmol / kg and an alicyclic structure content of 1,387 mmol / kg.

[Example 3]
350 parts by mass of PC-1 was added to a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, and a thermometer, and dehydration was performed at 120 to 130 ° C. at a degree of reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 117 parts by mass of SiPol-1, 453 parts by mass of DMF, and 272 parts by mass of toluene were added and thoroughly mixed with stirring. Thereafter, 93 parts by mass of IPDI and 0.3 parts by mass of stannous octoate were added, and reacted at 75 ° C. to obtain a solution of an urethane prepolymer having an isocyanate group.
Next, 635 parts by mass of DMF and 272 parts by mass of toluene were added to the solution of the urethane prepolymer, cooled to 30 ° C., 44 parts by mass of hydrogenated MDA was added, and chain elongation was performed by stirring. Thereafter, 181 parts by mass of IPA was added and mixed to obtain a urethane resin composition containing a urethane resin having a urea bond content of 694 mmol / kg and an alicyclic structure content of 1,387 mmol / kg.

Example 4
350 parts by mass of PC-1 was added to a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, and a thermometer, and dehydration was performed at 120 to 130 ° C. at a degree of reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 62 parts by mass of “X-22-176GX-A” (number average molecular weight; 13000, hereinafter abbreviated as “SiPol-2”) manufactured by Shin-Etsu Chemical Co., Ltd. and DMF 405 parts by mass and 270 parts by mass of ethyl acetate were added and thoroughly mixed with stirring. Thereafter, 103 parts by mass of IPDI and 0.3 parts by mass of stannous octoate were added, and reacted at 75 ° C. to obtain a solution of a urethane prepolymer having an isocyanate group.
Next, 944 parts by mass of DMF and 404 parts by mass of ethyl acetate are added to the solution of the urethane prepolymer, cooled to 30 ° C., 47 parts by mass of isophorone diamine (hereinafter “IPDA”) is added, and the chain is stirred. It was extended. Thereafter, 225 parts by mass of IPA were added and mixed to obtain a urethane resin composition containing a urethane resin having a content of urea bonds of 984 mmol / kg and a content of alicyclic structures of 1,317 mmol / kg.

[Example 5]
350 parts by mass of PC-1 was added to a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, and a thermometer, and dehydration was performed at 120 to 130 ° C. at a degree of reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 66 parts by mass of SiPol-1, 22 parts by mass of 1,4-cyclohexanedimethanol (hereinafter abbreviated as “CHDM”), 433 parts by mass of DMF, and ethyl acetate 260 parts by mass was added and thoroughly mixed with stirring. Thereafter, 109 parts by mass of IPDI and 0.3 parts by mass of stannous octoate were added, and reacted at 75 ° C. to obtain a solution of a urethane prepolymer having an isocyanate group.
Next, 606 parts by mass of DMF and 260 parts by mass of ethyl acetate were added to the solution of the urethane prepolymer, cooled to 30 ° C., and 30 parts by mass of hydrogenated MDA was added and stirred for chain elongation. Thereafter, 173 parts by mass of IPA was added and mixed to obtain a urethane resin composition containing a urethane resin having a urea bond content of 495 mmol / kg and an alicyclic structure content of 1,611 mmol / kg.

[Example 6]
In a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas inlet tube, and a thermometer, poly (hexamethylene) poly (tetramethylene) carbonate diol ("Duranol T4692" manufactured by Asahi Kasei Chemicals Corporation, number average molecular weight; 350 parts by mass of “PC-2”) was added, and dehydration was performed at 120 to 130 ° C. under a reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 62 parts by mass of SiPol-1, 398 parts by mass of DMF, and 239 parts by mass of ethyl acetate were added and thoroughly mixed with stirring. Thereafter, 82 parts by mass of IPDI and 0.3 parts by mass of stannous octoate were added, and reacted at 75 ° C. to obtain a solution of a urethane prepolymer having an isocyanate group.
Next, 557 parts by mass of DMF and 239 parts by mass of ethyl acetate were added to the solution of the urethane prepolymer, cooled to 30 ° C., and 36 parts by mass of hydrogenated MDA was added and stirred for chain elongation. Thereafter, 159 parts by mass of IPA was added and mixed to obtain a urethane resin composition containing a urethane resin having a urea bond content of 647 mmol / kg and an alicyclic structure content of 1,344 mmol / kg.

[Example 7]
350 parts by mass of PC-1 was added to a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, and a thermometer, and dehydration was performed at 120 to 130 ° C. at a degree of reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 62 parts by mass of SiPol-1, 406 parts by mass of DMF and 244 parts by mass of ethyl acetate were added and thoroughly mixed with stirring. Thereafter, 99 parts by mass of 4,4′-dicyclohexylmethane diisocyanate (hereinafter abbreviated as “hydrogenated MDI”) and 0.3 parts by mass of stannous octoate are added, and reacted at 75 ° C. A solution of urethane prepolymer having a group was obtained.
Next, 568 parts by mass of DMF and 244 parts by mass of ethyl acetate were added to the solution of the urethane prepolymer, cooled to 30 ° C., 30 parts by mass of IPDA was added, and chain elongation was performed by stirring. Thereafter, 162 parts by mass of IPA was added and mixed to obtain a urethane resin composition containing a urethane resin having a content of urea bond of 652 mmol / kg and a content of alicyclic structure of 1,723 mmol / kg.

[Example 8]
350 parts by mass of PC-1 was added to a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, and a thermometer, and dehydration was performed at 120 to 130 ° C. at a degree of reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 62 parts by mass of SiPol-2, 391 parts by mass of DMF, and 261 parts by mass of ethyl acetate were added and thoroughly mixed with stirring. Thereafter, 99 parts by mass of hydrogenated MDI and 0.3 parts by mass of stannous octoate were added, and reacted at 75 ° C. to obtain a solution of an isocyanate group-containing urethane prepolymer.
Next, 913 parts by mass of DMF and 391 parts by mass of ethyl acetate were added to the solution of the urethane prepolymer, cooled to 30 ° C., 33 parts by mass of IPDA were added, and chain elongation was performed by stirring. Thereafter, 217 parts by mass of IPA were added and mixed to obtain a urethane resin composition containing a urethane resin having a urea bond content of 714 mmol / kg and an alicyclic structure content of 1,746 mmol / kg.

[Example 9]
350 parts by mass of poly (hexamethylene) carbonate diol (number average molecular weight; 1000, hereinafter abbreviated as "PC-3") is added to a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas inlet tube, and a thermometer. Dehydration was performed at 120 to 130 ° C. under a reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 62 parts by mass of SiPol-1, 463 parts by mass of DMF, and 278 parts by mass of ethyl acetate were added and thoroughly mixed with stirring. Thereafter, 124 parts by mass of hydrogenated MDI and 0.3 parts by mass of stannous octoate were added, and reacted at 75 ° C. to obtain a solution of an urethane prepolymer having an isocyanate group.
Next, 648 parts by mass of DMF and 278 parts by mass of ethyl acetate were added to the solution of the urethane prepolymer, cooled to 30 ° C., 18 parts by mass of IPDA was added, and chain elongation was performed by stirring. Thereafter, 185 parts by mass of IPA was added and mixed to obtain a urethane resin composition containing a urethane resin having a content of urea bonds of 382 mmol / kg and a content of alicyclic structures of 1,900 mmol / kg.

[Example 10]
In a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas inlet tube, and a thermometer, 350 parts by mass of PC-1 and polytetramethylene glycol (number average molecular weight; 1,000, hereinafter abbreviated as "PTMG-1" 44 parts by mass) was subjected to dehydration at 120 to 130 ° C. under a reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 44 parts by mass of SiPol-2, 461 parts by mass of DMF, and 276 parts by mass of ethyl acetate were added and thoroughly mixed with stirring. Thereafter, 131 parts by mass of hydrogenated MDI and 0.3 parts by mass of stannous octoate were added, and reacted at 75 ° C. to obtain a solution of an isocyanate group-containing urethane prepolymer.
Next, 645 parts by mass of DMF and 276 parts by mass of ethyl acetate were added to the solution of the urethane prepolymer, cooled to 30 ° C., 45 parts by mass of IPDA were added, and chain elongation was performed by stirring. Thereafter, 184 parts by mass of IPA was added and mixed to obtain a urethane resin composition containing a urethane resin having a content of urea bonds of 862 mmol / kg and a content of alicyclic structures of 2,060 mmol / kg.

[Example 11]
350 parts by mass of PC-1 was added to a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, and a thermometer, and dehydration was performed at 120 to 130 ° C. at a degree of reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 66 parts by mass of SiPol-1, 22 parts by mass of 1,4-butanediol (hereinafter abbreviated as “BG”), 459 parts by mass of DMF, 276 parts of ethyl acetate The mass part was added and thoroughly mixed with stirring. Thereafter, 149 parts by mass of hydrogenated MDI and 0.3 parts by mass of stannous octoate were added and reacted at 75 ° C. to obtain a solution of an urethane prepolymer having an isocyanate group.
Next, 643 parts by mass of DMF and 276 parts by mass of ethyl acetate were added to the solution of the urethane prepolymer, cooled to 30 ° C., 26 parts by mass of hydrogenated MDA was added, and chain extension was performed by stirring. Thereafter, 184 parts by mass of IPA was added and mixed to obtain a urethane resin composition containing a urethane resin having a urea bond content of 404 mmol / kg and an alicyclic structure content of 2,259 mmol / kg.

Comparative Example 1
350 parts by mass of PC-1 was added to a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, and a thermometer, and dehydration was performed at 120 to 130 ° C. at a degree of reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 62 parts by mass of SiPol-1, 488 parts by mass of DMF, and 293 parts by mass of ethyl acetate were added and thoroughly mixed with stirring. Thereafter, 156 parts by mass of hydrogenated MDI and 0.3 parts by mass of stannous octoate were added and reacted at 75 ° C. to obtain a solution of an urethane prepolymer having an isocyanate group.
Next, 684 parts by mass of DMF and 293 parts by mass of ethyl acetate were added to the solution of the urethane prepolymer, cooled to 30 ° C., 83 parts by mass of hydrogenated MDA was added, and chain elongation was performed by stirring. Thereafter, 195 parts by mass of IPA is added and mixed to obtain a urethane resin composition containing a urethane resin having a urea bond content of 1,214 mmol / kg and an alicyclic structure content of 3,043 mmol / kg. The

Comparative Example 2
350 parts by mass of PC-1 was added to a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas introduction pipe, and a thermometer, and dehydration was performed at 120 to 130 ° C. at a degree of reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 64 parts by mass of SiPol-1, 13 parts by mass of BG, 547 parts by mass of DMF, and 234 parts by mass of ethyl acetate were added and thoroughly mixed with stirring. Thereafter, 85 parts by mass of IPDI and 0.3 parts by mass of stannous octoate were added, and reacted at 75 ° C. to obtain a solution of a urethane prepolymer having an isocyanate group.
Next, 391 parts by mass of DMF and 234 parts by mass of ethyl acetate were added to the solution of the urethane prepolymer, cooled to 30 ° C., 8 parts by mass of IPDA were added, and chain elongation was performed by stirring. Thereafter, 156 parts by mass of IPA was added and mixed to obtain a urethane resin composition containing a urethane resin having a content of urea linkage of 181 mmol / kg and a content of alicyclic structure of 827 mmol / kg.

Comparative Example 3
A polyester polyol (obtained by reacting BG and adipic acid in a nitrogen-substituted reaction vessel equipped with a stirrer, a nitrogen gas inlet tube, and a thermometer, number average molecular weight; 2,000, hereinafter, "PEs- 350 parts by mass of 1 ′ ′) was added, and dehydration was performed at 120 to 130 ° C. under a reduced pressure of 0.095 MPa. After dehydration, while cooling to 50 ° C., 62 parts by mass of SiPol-1, 398 parts by mass of DMF, and 239 parts by mass of ethyl acetate were added and thoroughly mixed with stirring. Thereafter, 82 parts by mass of IPDI and 0.3 parts by mass of stannous octoate were added, and reacted at 75 ° C. to obtain a solution of a urethane prepolymer having an isocyanate group.
Next, 558 parts by mass of DMF and 239 parts by mass of ethyl acetate were added to the solution of the urethane prepolymer, cooled to 30 ° C., 37 parts by mass of hydrogenated MDA was added, and chain elongation was performed by stirring. Thereafter, 159 parts by mass of IPA was added and mixed to obtain a urethane resin composition containing a urethane resin having a urea bond content of 664 mmol / kg and an alicyclic structure content of 1.359 mmol / kg.

[Evaluation method of hydrolysis resistance]
The urethane resin composition obtained in Examples and Comparative Examples is coated on a release paper using an applicator so that the thickness of the film after drying is 50 μm, and further 120 at 70 ° C., 120 The film was obtained by drying at 2 ° C for 2 minutes. The obtained film was cured for 5 weeks at 70 ° C. and 95% humidity. The tensile strength of the film was measured before and after curing using “Autograph AG-I” manufactured by Shimadzu Corporation in accordance with JIS-K7312 (1996), and after curing when the value before curing was 100. When the relative value of was 75 or more, it was evaluated as "A", when 50 or more and less than 75 as "B", and less than 50 as "C".

[Method of evaluating wear resistance]
100 parts by mass of the urethane resin composition obtained in Examples and Comparative Examples, 50 parts by mass of DMF, and 20 parts by mass of a colorant (“Dylac L-1770S” manufactured by DIC Corporation) The solution was coated on (DN-TP-155T manufactured by Dainippon Printing Co., Ltd.) so that the film thickness after drying was 30 μm, and dried at 90 ° C. for 1 minute and further at 120 ° C. for 2 minutes. Next, 100 parts by mass of a polyurethane-based adhesive ("Kurisbon TA-215FT" manufactured by DIC Corporation, resin solid content; 50% by mass), 50 parts by mass of DMF, cross-linking catalyst And 10 parts by mass of a polyisocyanate crosslinking agent ("Barnock D-750" manufactured by DIC Corporation), and the film thickness after drying is 50 μm on the dried film. It coated so that it might become. The laminate was immediately laminated with a T / R laminated blanket, dried at 100 ° C. for 1 minute, and further dried at 120 ° C. for 1 minute, aged at 40 ° C. for 3 days, and the release paper was peeled off to obtain a synthetic leather.
The planar abrasion test (JASO-M403-88B method, load: 1 kg, stroke: 140 mm) of the obtained synthetic leather was performed, and the number of times until the surface of the synthetic leather was worn and the base cloth could be confirmed was measured. When the number of times was 10,000 or more, it was evaluated as "A", when it was 5,000 or more and less than 10,000, "B", and when less than 5,000, it was evaluated as "C".

[Method of evaluating processability]
100 parts by mass of the urethane resin composition obtained in Examples and Comparative Examples, 50 parts by mass of DMF, and 20 parts by mass of a coloring agent ("Dyrac L-1770S" manufactured by DIC Corporation) It coats on the mold release paper (Asahi Roll Co., Ltd. "ARX-120" made by Asahi Roll Co., Ltd.) so that the film thickness after drying becomes 30 μm, and the film is dried at 80 ° C for 2 minutes and further at 120 ° C for 2 minutes. Obtained. Thereafter, the film floating from the release paper after leaving for 24 hours at room temperature was visually confirmed, and those without floating were "A" and those with partially floating were "B" floating over the entire surface. Those that were confirmed to have been evaluated as "C".

  It turned out that Examples 1-11 which are the urethane resin composition of this invention are excellent in hydrolysis resistance, abrasion resistance, and processability.

  On the other hand, Comparative Example 1 was an embodiment in which the content of the urea bond in the urethane resin exceeded the range defined in the present invention, but the processability was poor.

  Comparative Example 2 is an embodiment in which the content of the urea bond in the urethane resin is less than the range defined in the present invention, but the abrasion resistance was poor.

  Comparative Example 3 is an embodiment using a polyester polyol instead of the polycarbonate polyol (a1-1), but the hydrolysis resistance was poor.

Claims (4)

Urea obtained by reacting polycarbonate polyol (a1-1), silicone polyol (a1-2) represented by the following general formula (1), polyisocyanate (a2), and chain extender (a3) having an amino group A urethane resin composition comprising a urethane resin (A) having a content of bond in the range of 200 to 1,100 mmol / kg, and an organic solvent (B).

(In the formula (1), ^{R 1} and ^{R 2} each represents an alkyl group having 1 to 10 carbon atoms, X is shows a structure represented by the following formula (2), n represents an integer of 10 to 200. )

(In the formula (2), R ¹ represents an alkylene group having 1 to 10 carbon atoms, R ² represents an alkylene group having 1 to 8 carbon atoms, and R ³ represents a hydrogen atom or 1 to 10 carbon atoms Represents an alkyl group)

The urethane resin composition according to claim 1, wherein the polyisocyanate (a2) and / or the chain extender (a3) have an alicyclic structure. The urethane resin composition according to claim 2, wherein the urethane resin (A) contains an alicyclic structure in the range of 1,100 to 2,500 mmol / kg. The leather-like sheet obtained by forming into a film the urethane-resin composition of any one of Claims 1-3.