Detailed Description
The urethane resin composition of the present invention contains a urethane resin (a) that is produced from a reactive silicone(s) having a functional group that reacts with an isocyanate group, a urethane resin (B) that is not produced from the reactive silicone(s), and water (C).
The urethane resin (a) is required to be made of a reactive silicone(s) having a functional group that reacts with an isocyanate group. By using the reactive silicone(s), the slidability of the sheet surface can be improved, and squeak noise can be reduced.
The urethane resin (a) can be dispersed in an aqueous medium (C) described later, and examples thereof include: urethane resins having hydrophilic groups such as anionic groups, cationic groups, and nonionic groups; urethane resin forcibly dispersed in the aqueous medium (C) with an emulsifier. These urethane resins (A) may be used alone, or 2 or more of them may be used in combination. Among these, from the viewpoint of production stability, a urethane resin having a hydrophilic group is preferably used, and from the viewpoint of achieving more excellent reduction in squeak noise, a urethane resin having an anionic group is more preferably used.
Examples of the method for obtaining the urethane resin having an anionic group include: a method of using 1 or more compounds selected from a diol compound having a carboxyl group and a compound having a sulfonyl group as a raw material.
Examples of the diol compound having a carboxyl group include 2, 2-dimethylolpropionic acid, 2-dimethylolbutyric acid, 2-dimethylolpropionic acid, and 2, 2-pentanoic acid. These compounds may be used alone, or 2 or more of them may be used in combination.
As the above-mentioned compound having a sulfonyl group, for example, there can be used: 3, 4-diaminobutanesulfonic acid, 3, 6-diamino-2-toluenesulfonic acid, 2, 6-diaminobenzenesulfonic acid, N- (2-aminoethyl) -2-aminoethanesulfonic acid, and the like. These compounds may be used alone, or 2 or more of them may be used in combination.
In the urethane resin composition, a part or all of the carboxyl groups and the sulfonyl groups may be neutralized with a basic compound. Examples of the basic compound include organic amines such as ammonia, triethylamine, pyridine, and morpholine; alkanolamines such as monoethanolamine and dimethylethanolamine; and metal alkali compounds containing sodium, potassium, lithium, calcium, and the like.
When an anionic group-containing urethane resin (hereinafter abbreviated as "anionic urethane resin") is used as the urethane resin (a), the acid value of the anionic urethane resin is preferably 20mgKOH/g or less, more preferably 3 to 17mgKOH/g, still more preferably 5 to 14mgKOH/g, and particularly preferably 5 to 13mgKOH/g, from the viewpoint of promoting hydrolysis by a hydrophilic group to obtain more excellent hydrolysis resistance. The method for measuring the acid value of the anionic urethane resin is described in examples described later. The method for adjusting the acid value of the anionic urethane resin includes a method of adjusting the amounts of the diol compound having a carboxyl group and the compound having a sulfonyl group to be used for imparting an anionic group.
The amount of the diol compound having a carboxyl group and the compound having a sulfonyl group used is preferably in the range of 0.1 to 5% by mass, more preferably in the range of 0.3 to 4% by mass, and still more preferably in the range of 0.5 to 3.5% by mass of the total mass of the raw materials constituting the urethane resin (a), from the viewpoint of obtaining more excellent hydrolysis resistance.
Examples of the method for obtaining the urethane resin having a cationic group include a method in which 1 or 2 or more kinds of compounds having an amino group are used as a raw material.
As the compound having an amino group, for example, there can be used: compounds having a primary amino group and a secondary amino group such as triethylenetetramine and diethylenetriamine; and compounds having a tertiary amino group such as N-alkyldialkanolamines such as N-methyldiethanolamine and N-ethyldiethanolamine, and N-alkyldiaminoalkylamines such as N-methyldiaminoethylamine and N-ethyldiaminoethylamine. These compounds may be used alone, or 2 or more of them may be used in combination.
As a method for obtaining the urethane resin having a nonionic group, there can be mentioned, for example, a method using, as a raw material, 1 or 2 or more compounds having an oxyethylene structure (Japanese patent publication No. キシ, チレン).
As the compound having an oxyethylene structure, for example, there can be used: polyether polyols having an oxyethylene structure such as polyoxyethylene glycol, polyoxyethylene polyoxypropylene glycol, and polyoxyethylene polyoxytetramethylene glycol. These compounds may be used alone, or 2 or more of them may be used in combination.
As the emulsifier that can be used in obtaining the urethane resin forcibly dispersed in the aqueous medium (C), for example, there can be used: nonionic emulsifiers such as polyoxyethylene nonylphenyl ether, polyoxyethylene lauryl ether, polyoxyethylene styrylphenyl ether, polyoxyethylene sorbitol tetraoleate, and polyoxyethylene-polyoxypropylene copolymer; anionic emulsifiers such as fatty acid salts such as sodium oleate, alkyl sulfate ester salts, alkylbenzene sulfonates, alkyl sulfosuccinates, naphthalene sulfonates, polyoxyethylene alkyl sulfates, sodium alkane sulfonates, and sodium alkyl diphenyl ether sulfonates; and cationic emulsifiers such as alkylamine salts, alkyltrimethylammonium salts, and alkyldimethylbenzylammonium salts. These emulsifiers may be used alone or in combination of 2 or more.
Specific examples of the urethane resin (a) include: a polyol (a1), a chain extender (a2), a raw material for producing the urethane resin having a hydrophilic group, and a reactant of the reactive silicone(s) having a functional group that reacts with an isocyanate group and a polyisocyanate (a 3).
As the polyol (a1), for example, there can be used: polyether polyols, polyester polyols, polyacrylic polyols, polycarbonate polyols, polybutadiene polyols, and the like. These polyols may be used alone, or 2 or more kinds may be used in combination. As the polyol (a1), a polycarbonate polyol is preferably used from the viewpoint of obtaining more excellent abrasion resistance, chemical resistance and weather resistance.
As the polycarbonate polyol, for example, a reactant of a carbonate and/or phosgene and a compound having 2 or more hydroxyl groups can be used.
Examples of the carbonate include dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, and propylene carbonate. These compounds may be used alone, or 2 or more of them may be used in combination.
As the compound having 2 or more hydroxyl groups, for example, there can be used: ethylene glycol, propylene glycol, 1, 3-propanediol, 1, 4-butanediol, 1, 3-butanediol, 1, 2-butanediol, 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, 3-methylpentanediol, neopentyl glycol, and mixtures thereof, Trimethylolethane, glycerol, and the like. These compounds may be used alone, or 2 or more of them may be used in combination. Among them, from the viewpoint of obtaining more excellent abrasion resistance, chemical resistance and weather resistance, 1 or more compounds selected from the group consisting of 1, 3-propanediol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 1, 4-cyclohexanedimethanol, 3-methylpentanediol and 1, 10-decanediol are preferably used, and 1, 6-hexanediol is more preferred.
The amount of the polycarbonate polyol used is preferably 85% by mass or more, more preferably 90% by mass or more, and still more preferably 95% by mass or more of the polyol (a1), from the viewpoint of obtaining more excellent chemical resistance, mechanical strength, abrasion resistance, and weather resistance.
The number average molecular weight of the polycarbonate polyol is preferably in the range of 100 to 100000, more preferably in the range of 150 to 10000, and even more preferably in the range of 500 to 5000, from the viewpoint of obtaining more excellent chemical resistance, mechanical strength, abrasion resistance, and weather resistance. The number average molecular weight of the polycarbonate polyol is a value measured by a Gel Permeation Chromatography (GPC) method.
The number average molecular weight of the polyol (a1) other than the polycarbonate polyol is preferably in the range of 500 to 100000, more preferably 700 to 50000, and still more preferably 800 to 10000, from the viewpoint of obtaining more excellent weather resistance. The number average molecular weight of the polyol (a1) is a value measured by a Gel Permeation Chromatography (GPC) method.
The amount of the polyol (a1) used is preferably in the range of 40 to 90% by mass, more preferably in the range of 45 to 88% by mass, and still more preferably in the range of 50 to 85% by mass of the total mass of the raw materials constituting the urethane resin (a), from the viewpoint of further excellent chemical resistance, mechanical strength, abrasion resistance, weather resistance, and mechanical strength.
The chain extender (a2) is, for example, a chain extender having a number average molecular weight in the range of 50 to 450 (excluding the polycarbonate polyol), and specifically, there can be used: chain extenders having an amino group such as ethylenediamine, 1, 2-propylenediamine, 1, 6-hexamethylenediamine, piperazine, 2, 5-dimethylpiperazine, isophoronediamine, 1, 2-cyclohexanediamine, 1, 3-cyclohexanediamine, 1, 4-cyclohexanediamine, 4 ' -dicyclohexylmethanediamine, 3 ' -dimethyl-4, 4 ' -dicyclohexylmethanediamine, 1, 4-cyclohexanediamine, and hydrazine; and chain extenders having a hydroxyl group such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1, 3-propanediol, 1, 3-butanediol, 1, 4-butanediol, hexamethylene glycol, sucrose, methylene glycol, glycerin, sorbitol, bisphenol a, 4 '-dihydroxybiphenyl, 4' -dihydroxydiphenyl ether, trimethylolpropane, and the like. These chain extenders may be used alone, or 2 or more of them may be used in combination.
Among the chain extenders (a3), from the viewpoint of obtaining more excellent chemical resistance, mechanical strength, abrasion resistance and weather resistance, a chain extender having an amino group is preferably used, more preferably piperazine and/or hydrazine, and the total amount of piperazine and hydrazine is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 60% by mass or more of the chain extender (a 2). The chain extender (a2) preferably has an average functional group number of less than 3, more preferably less than 2.5.
The amount of the chain extender (a2) used is preferably in the range of 0.1 to 10 mass%, more preferably 0.5 to 7 mass%, and still more preferably 0.8 to 5 mass% of the total mass of the raw materials constituting the urethane resin (a) from the viewpoint of durability such as hydrolysis resistance and heat resistance.
From the viewpoint of introducing the reactive silicone(s) having a functional group reactive with an isocyanate group into the urethane resin (a) to achieve more excellent reduction in squeak noise, the reactive silicone(s) preferably has a number average molecular weight of 500 or more, more preferably 2000 or more, more preferably 4000 or more, still more preferably 4500 to 50000, still more preferably 4700 to 30000, and particularly preferably 5000 to 20000. The number average molecular weight of the reactive silicone(s) is a value measured by a Gel Permeation Chromatography (GPC) method.
As the reactive silicone(s), for example, there can be used: a single-terminal diol-type reactive silicone represented by the following formula (1), a single-terminal monool-type reactive silicone, a single-terminal diamine-type reactive silicone and a single-terminal monoamine-type reactive silicone, a both-terminal diol-type reactive silicone represented by the following formula (2), a both-terminal diamine-type reactive silicone, a both-terminal dimercapto-type reactive silicone and a both-terminal disilanol-type reactive silicone, a side chain monoamine-type reactive silicone represented by the following formula (3), and the like. These reactive silicones may be used alone, or 2 or more kinds may be used in combination.
[ chemical formula 1]
(in the formula (1), R1And R2Each independently represents an alkyl group having 1 to 10 carbon atoms, X represents a structure represented by the following formulae (X-1) to (X-12), and n represents an integer in the range of 50 to 670. )
[ chemical formula 2]
(in the formulae (X-1) and (X-2), R1And R2Each independently represents an alkylene group having 1 to 10 carbon atoms, R3Represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. )
[ chemical formula 3]
(in the formulae (X-3) and (X-4), R1An alkylene group having 1 to 10 carbon atoms, R2Represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. )
[ chemical formula 4]
(in the formulae (X-5) and (X-6), R1An alkylene group having 1 to 10 carbon atoms, R2Represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. )
[ chemical formula 5]
(in the formulae (X-7) and (X-8), R1And R2Each independently represents an alkylene group having 1 to 10 carbon atoms, R3Represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. )
[ chemical formula 6]
-R1-O-R2-OH (X-9)
-R1-O-R2-NH2 (X-10)
(in the formulae (X-9) and (X-10), R1And R2Each independently represents an alkylene group having 1 to 10 carbon atoms. )
[ chemical formula 7]
-R1-OH (X-11)
-R1-NH2 (X-12)
(in the formulae (X-11) and (X-12), R1An alkylene group having 1 to 10 carbon atoms. )
[ chemical formula 8]
(in the formula (2), R1Represents an alkyl group having 1 to 10 carbon atoms, Y represents a structure represented by the following formulae (Y-1) to (Y-5), and n represents an integer in the range of 50 to 670. )
[ chemical formula 9]
-OH (Y-1)
[ chemical formula 10]
-R1-OH (Y-2)
-R1-NH2 (Y-3)
-R1-SH (Y-4)
(in formulae (Y-2) to (Y-4), R1An alkylene group having 1 to 10 carbon atoms. )
[ chemical formula 11]
-R1-O-R2-OH (Y-5)
(in the formula (Y-5), R1And R2Each independently represents an alkylene group having 1 to 10 carbon atoms. )
[ chemical formula 12]
(in the formula (3), R1And R2Each represents an alkyl group having 1 to 8 carbon atoms, Z represents a structure represented by the following formulae (Z-1) to (Z-2), m represents an integer in the range of 50 to 670, and n represents an integer in the range of 1 to 10. )
[ chemical formula 13]
-R1-NH2 (Z-1)
(in the formula (Z-1), R1An alkylene group having 1 to 10 carbon atoms. )
[ chemical formula 14]
(in the formula (Z-2), R1And R2Each independently represents an alkylene group having 1 to 10 carbon atoms. )
The reactive silicone(s) is preferably a reactive silicone represented by the above formula (1), more preferably a reactive silicone represented by the above formula (1) in which X is selected from the above groups, from the viewpoints of imparting higher slidability, further reducing squeak noise, and obtaining more excellent abrasion resistance and hydrolysis resistance by introducing a silicone chain into a side chain of the urethane resin (a)More preferably, the reactive silicone represented by the formula (X-1) and/or (X-7) is used as 1 or more of the reactive silicones represented by the formulae (X-1), (X-7) and (X-9). In addition, it is preferable to use: r in the above formula (1)1And R2Each represents an alkyl group having 1 to 3 carbon atoms, n is an integer of 50 to 270, and R in the formulae (X-1) and (X-7)1And R2Each is an alkylene group having 1 to 3 carbon atoms, R3A substance which represents an alkyl group having 1 to 3 carbon atoms.
As the above-mentioned preferred reactive silicone(s), for example, "Silaplane FM-3321", "Silaplane FM-3325", "Silaplane FM-4421", "Silaplane FM-4425", "Silaplane FM-0421", "Silaplane FM-0425", "Silaplane FM-DA 21", "Silaplane FM-DA 26", manufactured by shin-Etsu chemical industry Co., Ltd. "X-22-176 GX-A" and "X-22-176F" are commercially available.
The amount of the reactive silicone(s) used is preferably in the range of 1 to 25% by mass, more preferably in the range of 3 to 20% by mass, and even more preferably in the range of 3.8 to 19% by mass of the total mass of the raw materials constituting the urethane resin (a), from the viewpoint of further reducing squeak noise and obtaining more excellent abrasion resistance and hydrolysis resistance.
As the polyisocyanate (a3), for example, there can be used: aromatic polyisocyanates such as phenylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, naphthalene diisocyanate, polymethylene polyphenyl polyisocyanate, and carbodiimide diphenylmethane polyisocyanate; aliphatic polyisocyanates and/or alicyclic polyisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, cyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, dimer acid diisocyanate, and norbornene diisocyanate. These polyisocyanates may be used alone, or 2 or more kinds may be used in combination. Among these, from the viewpoint of resistance to discoloration by light, aliphatic polyisocyanates and/or alicyclic polyisocyanates are preferably used, more preferably 1 or more polyisocyanates selected from the group consisting of hexamethylene diisocyanate, isophorone diisocyanate and dicyclohexylmethane diisocyanate, and still more preferably alicyclic polyisocyanates.
The amount of the polyisocyanate (a3) used is preferably within a range of 5 to 40% by mass, more preferably within a range of 7 to 30% by mass, and still more preferably within a range of 10 to 25% by mass of the total mass of the raw materials constituting the urethane resin (a), from the viewpoints of production stability and mechanical properties of the obtained coating film.
Examples of the method for producing the urethane resin (a) include: a method in which the polyol (a1), the chain extender (a2), the raw material for producing the urethane resin having a hydrophilic group, the reactive silicone(s), and the polyisocyanate (a3) are added and reacted at once. The reaction is carried out at 50 to 100 ℃ for 3 to 10 hours, for example.
The molar ratio [ isocyanate group/total of functional groups reactive with isocyanate group ] of the total of the hydroxyl group of the polyol (a1), the hydroxyl group and the amino group of the chain extender (a2), the functional group reactive with isocyanate group of the raw material for producing the urethane resin having a hydrophilic group, and the functional group reactive with isocyanate group of the reactive silicone(s) to the isocyanate group of the polyisocyanate (a3) in producing the urethane resin (a) is preferably in the range of 0.8 to 1.2, and more preferably in the range of 0.9 to 1.1.
In the production of the urethane resin (a), it is preferable to deactivate the isocyanate groups remaining in the urethane resin (a). When the isocyanate group is inactivated, an alcohol having 1 hydroxyl group such as methanol is preferably used. The amount of the alcohol used is preferably in the range of 0.001 to 10 parts by mass per 100 parts by mass of the urethane resin (a).
In addition, an organic solvent may be used in the production of the urethane resin (a). As the organic solvent, for example, there can be used: ketone compounds such as acetone and methyl ethyl ketone; ether compounds such as tetrahydrofuran and dioxane; acetate compounds such as ethyl acetate and butyl acetate; nitrile compounds such as acetonitrile; amide compounds such as dimethylformamide and N-methylpyrrolidone. These organic solvents may be used alone, or 2 or more of them may be used in combination. The organic solvent is preferably removed by distillation or the like when obtaining the aqueous urethane resin composition.
The urethane resin (B) is required to be a urethane resin which does not use the reactive silicone(s) as a raw material. Since the urethane resin (A) alone has a low coefficient of dynamic friction on the surface of the coating film, the urethane resins (A) and (B) can be used in combination to achieve both a reduction in squeak noise and a high coefficient of dynamic friction.
The urethane resin (B) is also dispersible in water (C) in the same manner as the urethane resin (a), and for example, there can be used: urethane resins having hydrophilic groups such as anionic groups, cationic groups, and nonionic groups; urethane resin forcedly dispersed in water (B) with an emulsifier, and the like. These urethane resins (B) may be used alone, or 2 or more of them may be used in combination. As the raw material for obtaining these urethane resins, the same raw materials as those usable for producing the urethane resin (a) can be used. Among them, from the viewpoint of obtaining more excellent water dispersion stability, dynamic friction coefficient, chemical resistance, abrasion resistance and weather resistance, a urethane resin having a hydrophilic group is preferably used, and a urethane resin having an anionic group is more preferably used.
The amount of the raw material used for producing the urethane resin having a hydrophilic group is preferably in the range of 0.1 to 15% by mass, more preferably 1 to 10% by mass, and still more preferably 1.5 to 7% by mass of the raw material of the urethane resin (B), from the viewpoint of obtaining more excellent dynamic friction coefficient, chemical resistance, abrasion resistance, hydrolysis resistance, and weather resistance.
As the urethane resin (B), specifically, for example, there can be used: reactants of a raw material for producing the above urethane resin having a hydrophilic group, polyisocyanate (b1), polyol (b2), and chain extender (b 3). For the reaction, a known urethanization reaction can be used.
As the polyisocyanate (b1), the same polyisocyanate as the polyisocyanate (a3) can be used. Among these, from the viewpoint of obtaining more excellent dynamic friction coefficient, chemical resistance, abrasion resistance and weather resistance, alicyclic polyisocyanate is preferably used, more preferably polyisocyanate having a structure in which at least 1 or more nitrogen atoms of an isocyanate group are directly linked to a cyclohexane ring is used, and further preferably isophorone diisocyanate and/or dicyclohexylmethane diisocyanate is used. The amount of the alicyclic polyisocyanate used is preferably 30% by mass or more, more preferably 40% by mass or more, and still more preferably 50% by mass or more of the polyisocyanate (b1), from the viewpoint of obtaining more excellent chemical resistance, abrasion resistance, and weather resistance.
When the urethane resin composition of the present invention is used as a surface treatment agent, in the case where further light resistance is required, the alicyclic polyisocyanate and the aliphatic polyisocyanate are preferably used in combination as the polyisocyanate (b1), and hexamethylene diisocyanate is preferably used as the aliphatic polyisocyanate. The content of the alicyclic polyisocyanate in the polyisocyanate (b1) in this case is preferably 30% by mass or more, more preferably 40% by mass or more, and still more preferably 50% by mass or more.
The amount of the polyisocyanate (B1) used is preferably in the range of 5 to 50 mass%, more preferably in the range of 15 to 40 mass%, and still more preferably in the range of 20 to 37 mass% of the raw material of the urethane resin (B), from the viewpoint of obtaining more excellent dynamic friction coefficient, chemical resistance, abrasion resistance, and weather resistance.
As the polyol (b2), the same polyol as the polyol (a1) can be used. Among them, polycarbonate polyols are preferably used from the viewpoint of obtaining more excellent chemical resistance, abrasion resistance and weather resistance.
The amount of the polycarbonate polyol used is preferably 85% by mass or more, more preferably 90% by mass or more, and still more preferably 95% by mass or more of the polyol (b2), from the viewpoint of obtaining more excellent chemical resistance, abrasion resistance, and weather resistance.
The number average molecular weight of the polycarbonate polyol is preferably in the range of 100 to 100000, more preferably in the range of 150 to 10000, and even more preferably in the range of 200 to 2500, from the viewpoint of obtaining more excellent chemical resistance, mechanical strength, abrasion resistance, and weather resistance. The number average molecular weight of the polycarbonate polyol is a value measured by a Gel Permeation Chromatography (GPC) method.
The number average molecular weight of the polyol (b2) other than the polycarbonate polyol is preferably in the range of 500 to 100000, more preferably 700 to 50000, and still more preferably 800 to 10000, from the viewpoint of obtaining more excellent weather resistance. The number average molecular weight of the polyol (b2) is a value measured by a Gel Permeation Chromatography (GPC) method.
The amount of the polyol (B2) used is preferably in the range of 30 to 80% by mass, more preferably 40 to 75% by mass, and still more preferably 50 to 70% by mass of the raw material of the urethane resin (B).
As the chain extender (b3), the same chain extender as the chain extender (a2) can be used. Among them, from the viewpoint of obtaining more excellent dynamic friction coefficient, chemical resistance, mechanical strength, abrasion resistance and weather resistance, it is preferable to use a chain extender having an amino group, more preferably piperazine and/or hydrazine, and the total amount of piperazine and hydrazine is preferably 30% by mass or more, more preferably 50% by mass or more, further preferably 60% by mass or more, and particularly preferably 80% by mass or more of the chain extender (b 3). In addition, as the chain extender (b3), the average number of functional groups is preferably less than 3, more preferably less than 2.5. In addition, the first and second substrates are,
the amount of the chain extender (B3) used is preferably in the range of 0.5 to 10% by mass, more preferably in the range of 0.7 to 5% by mass, and still more preferably in the range of 0.9 to 2.3 in the raw material of the urethane resin (B), from the viewpoint of obtaining more excellent dynamic friction coefficient, chemical resistance, mechanical strength, abrasion resistance, and weather resistance.
Examples of the method for producing the urethane resin (B) include the following methods: a method in which the polyisocyanate (b1), the polyol (b2), and raw materials for producing the urethane resin having a hydrophilic group are reacted with each other to produce a urethane prepolymer having an isocyanate group, and then the urethane prepolymer is reacted with the chain extender (b3) to produce a urethane prepolymer having an isocyanate group; a method of adding and reacting the polyisocyanate (b1), the polyol (b2), a raw material for producing a urethane resin having a hydrophilic group, and the chain extender (b3) at once. Examples of the reaction include a reaction at 50 to 100 ℃ for 3 to 10 hours.
The molar ratio [ (isocyanate group)/(hydroxyl group and amino group) ] of the total of the hydroxyl group of the raw material for producing the hydrophilic group-containing urethane resin, the hydroxyl group of the polyol (b2), and the hydroxyl group and amino group of the chain extender (b3) to the isocyanate group of the polyisocyanate (b1) is preferably in the range of 0.8 to 1.2, and more preferably in the range of 0.9 to 1.1.
In the production of the urethane resin (B), it is preferable to deactivate the isocyanate groups remaining in the urethane resin (B). When the isocyanate group is inactivated, an alcohol having 1 hydroxyl group such as methanol is preferably used. The amount of the alcohol used is preferably in the range of 0.001 to 10 parts by mass per 100 parts by mass of the urethane resin (B).
In addition, an organic solvent may be used in the production of the urethane resin (B). As the organic solvent, for example, there can be used: ketone compounds such as acetone and methyl ethyl ketone; ether compounds such as tetrahydrofuran and dioxane; acetate compounds such as ethyl acetate and butyl acetate; nitrile compounds such as acetonitrile; amide compounds such as dimethylformamide and N-methylpyrrolidone. These organic solvents may be used alone, or 2 or more of them may be used in combination. The organic solvent is preferably finally removed by distillation or the like.
The content of the urethane bond in the urethane resin (a) is preferably in the range of 980 to 4000mmol/kg, more preferably in the range of 1000 to 3500mmol/kg, even more preferably in the range of 1100 to 3000mmol/kg, and still more preferably in the range of 1150 to 2500mmol/kg, from the viewpoint of obtaining more excellent chemical resistance, abrasion resistance, and weather resistance. The urethane bond content of the urethane resin (a) is a value calculated from the amounts of the polyisocyanate (a1), the polyol (a2), the raw material for producing a urethane resin having a hydrophilic group, and the chain extender (a3) added.
The content of the urea bond in the urethane resin (a) is preferably 315 to 850mmol/kg, more preferably 350 to 830mmol/kg, still more preferably 400 to 800mmol/kg, and yet more preferably 410 to 770mmol/kg, from the viewpoint of obtaining more excellent chemical resistance, abrasion resistance, and weather resistance. The content of the urea bond in the urethane resin (a) is a value calculated from the amounts of the polyisocyanate (a1), the polyol (a2), the raw material for producing a urethane resin having a hydrophilic group, and the chain extender (a3) added.
The content of the alicyclic structure in the urethane resin (a) is preferably in the range of 500 to 3000mmol/kg, more preferably in the range of 600 to 2900mmol/kg, and still more preferably in the range of 700 to 2700mmol/kg, from the viewpoint of obtaining more excellent chemical resistance, abrasion resistance, and weather resistance. The content of the alicyclic structure in the urethane resin (a) is a value calculated from the amounts of the polyisocyanate (a1), the polyol (a2), the raw material for producing a urethane resin having a hydrophilic group, and the chain extender (a3) added.
The mass ratio [ (a)/(B) ] of the urethane resin (a) to the urethane resin (B) is preferably in the range of 5/95 to 95/5, more preferably in the range of 10/90 to 90/10, and even more preferably in the range of 13/87 to 87/13, from the viewpoint of further improving the balance between the reduction in squeak noise and the coefficient of dynamic friction.
The total content of the urethane resin (a) and the urethane resin (B) is preferably in the range of 3 to 50% by mass, and more preferably in the range of 5 to 30% by mass in the urethane resin composition, from the viewpoints of coatability, workability, and storage stability.
As the water (C), ion-exchanged water, distilled water, or the like can be used. The content of the water (C) is preferably in the range of 30 to 95% by mass, more preferably in the range of 50 to 90% by mass in the urethane resin composition, from the viewpoint of coatability, workability and storage stability of the urethane resin composition.
The urethane resin composition of the present invention contains the above-mentioned urethane resin (a), urethane resin (B) and water (C) as essential components, but other additives may be used as necessary.
As the other additives, for example, there can be used: fillers (D), crosslinking agents (E), emulsifiers, defoaming agents, leveling agents, thickeners, viscoelasticity modifiers, defoaming agents, wetting agents, dispersants, preservatives, plasticizers, penetrants, fragrances, bactericides, acaricides, mildewcides, ultraviolet absorbers, antioxidants, antistatic agents, flame retardants, dyes, pigments (e.g., titanium white, red iron, phthalocyanine, carbon black, permanent yellow, etc.), and the like. These additives may be used alone, or 2 or more of them may be used in combination.
When the urethane resin composition of the present invention is used as a surface treatment agent, the other additive preferably contains a filler (D) for imparting matte feel to the coating film thereof, and a crosslinking agent (E) for improving the mechanical strength of the coating film.
Examples of the filler (D) include silica particles, organic microbeads, calcium carbonate, magnesium carbonate, barium carbonate, talc, aluminum hydroxide, calcium sulfate, kaolin, mica (japanese patent No.), asbestos, mica (japanese patent No. マイカ), calcium silicate, and aluminum silicate. These fillers may be used alone, or 2 or more of them may be used in combination.
As the silica particles, for example, dry silica, wet silica, or the like can be used. Among them, dry silica is preferable in terms of high scattering effect and wide adjustment range of the gloss value. The average particle diameter of these silica particles is preferably in the range of 2 to 14 μm, and more preferably in the range of 3 to 12 μm. The average particle size of the silica particles is a particle size (particle size in D50 in the particle size distribution) when the cumulative amount of the particles accounts for 50% in a cumulative particle amount curve of the particle size distribution measurement result.
As the organic beads, for example, acrylic beads, urethane beads, silicon beads, olefin beads, and the like can be used.
The amount of the filler (D) used may be appropriately determined depending on the matte feeling to be imparted, and is, for example, preferably in the range of 1 to 30 parts by mass, and more preferably in the range of 3 to 10 parts by mass, based on 100 parts by mass of the total of the urethane resins (a) and (B).
As the crosslinking agent (E), for example, there can be used: isocyanate crosslinking agents, epoxy crosslinking agents, carbodiimide crosslinking agents, oxazolidine crosslinking agents, oxazoline crosslinking agents, melamine crosslinking agents, and the like. These crosslinking agents may be used alone, or 2 or more kinds may be used in combination.
The amount of the crosslinking agent (E) used is, for example, preferably 5 to 40 parts by mass, and more preferably 10 to 30 parts by mass, based on 100 parts by mass of the total of the urethane resins (a) and (B).
As described above, the urethane resin composition of the present invention can provide a film having a low squeak noise and a high coefficient of dynamic friction. Therefore, the urethane resin composition of the present invention can be suitably used as a surface treatment agent for various articles such as synthetic leather, polyvinyl chloride (PVC) leather, thermoplastic olefin resin (TPO) leather, dashboards, instrument panels, and the like.
The article of the present invention has a layer formed by using the surface treatment agent.
Specific examples of the article include: automobile interior sheets, sports shoes, clothing, furniture, thermoplastic olefin (TPO) leather, instrument panels, and the like, using synthetic leather, artificial leather, natural leather, and polyvinyl chloride (PVC) leather.
The thickness of the layer formed by the surface treatment agent is, for example, in the range of 0.1 to 100 μm.
Examples
The present invention will be described in more detail below with reference to examples.
Synthesis example 1 preparation of aqueous Dispersion of urethane resin (A-1)
A four-necked flask equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen reflux tube was charged with 500 parts by mass of polycarbonate diol ("DURANOL T5652" manufactured by Asahi Kasei Chemicals K.K., number average molecular weight: 2000), 26 parts by mass of one-terminal diol-type reactive silicone ("X-22-176 GX-A" manufactured by shin-Etsu chemical Co., Ltd., number average molecular weight: 14000, hereinafter abbreviated as "one-terminal diol-type Si-1"), 8 parts by mass of 2, 2-dimethylolpropionic acid, and 269 parts by mass of methyl ethyl ketone under a nitrogen stream, and after uniform mixing, 86 parts by mass of isophorone diisocyanate was added, and then 0.1 part by mass of dibutyltin dilaurate was added to react at 70 ℃ for about 4 hours, thereby obtaining a methyl ethyl ketone solution of a urethane prepolymer having an isocyanate group at a molecular terminal. Then, 6 parts by mass of triethylamine was added to the methyl ethyl ketone solution of the obtained urethane prepolymer, the carboxyl groups were neutralized with the urethane prepolymer, ion-exchanged water was added, and then 7 parts by mass of piperazine was added to carry out a reaction. After the completion of the reaction, methyl ethyl ketone was distilled off under reduced pressure to obtain an aqueous dispersion (nonvolatile content; 30% by mass, acid value; 5KOHmg/g) of the urethane resin (A-1).
Synthesis example 2 preparation of aqueous Dispersion of urethane resin (A-2)
A four-necked flask equipped with a stirrer, a reflux condenser, a thermometer and a nitrogen reflux tube was charged with 500 parts by mass of polycarbonate diol ("DURANOL T5652" manufactured by Asahi Kasei Chemicals K.K., number average molecular weight: 2000), 26 parts by mass of one-terminal diol-type reactive silicone ("X-22-176 GX-A" manufactured by shin-Etsu chemical Co., Ltd., number average molecular weight: 14000, hereinafter abbreviated as "one-terminal diol-type Si-1"), 8 parts by mass of 2, 2-dimethylolpropionic acid, and 269 parts by mass of methyl ethyl ketone under a nitrogen stream, and after uniform mixing, 86 parts by mass of isophorone diisocyanate was added, and then 0.1 part by mass of dibutyltin dilaurate was added to react at 70 ℃ for about 4 hours, thereby obtaining a methyl ethyl ketone solution of a urethane prepolymer having an isocyanate group at a molecular terminal. Then, 6 parts by mass of triethylamine was added to the methyl ethyl ketone solution of the obtained urethane prepolymer, the carboxyl groups were neutralized in the urethane prepolymer, ion-exchanged water was added, and then 2.6 parts by mass of hydrazine was added to carry out a reaction. After the completion of the reaction, methyl ethyl ketone was distilled off under reduced pressure to obtain an aqueous dispersion (nonvolatile content; 30% by mass, acid value; 5KOHmg/g) of the urethane resin (A-2).
Synthesis example 3 preparation of aqueous Dispersion of urethane resin (B-1)
A four-neck flask equipped with a stirrer, a thermometer and a nitrogen reflux tube was charged with 250 parts by mass of methyl ethyl ketone and 0.001 part by mass of stannous octoate, and then 200 parts by mass of polycarbonate polyol-1 (starting from 1, 4-butanediol and 1, 6-hexanediol and having a number average molecular weight of 1000), 15 parts by mass of 2, 2-dimethylolpropionic acid, 49 parts by mass of isophorone diisocyanate and 34 parts by mass of hexamethylene diisocyanate were added and reacted at 70 ℃ for 1 hour to obtain a methyl ethyl ketone solution of a urethane prepolymer.
Then, 6.8 parts by mass of hydrazine and 15 parts by mass of triethylamine were mixed with the methyl ethyl ketone solution of the urethane prepolymer, and 820 parts by mass of ion-exchanged water was added to obtain an emulsion in which the urethane resin (B-1) was dispersed in water.
Then, methyl ethyl ketone was distilled off from the above emulsion, and ion-exchanged water was further added to obtain an aqueous dispersion of urethane resin (B-1) having a nonvolatile content of 30 mass%.
The obtained urethane resin (B-1) had a urethane bond content of 2052mmol/kg, a urea bond content of 698mmol/kg and an alicyclic structure content of 715 mmol/kg.
Synthesis example 4 preparation of aqueous Dispersion of urethane resin (B-2)
250 parts by mass of methyl ethyl ketone and 0.001 part by mass of stannous octoate were charged into a four-neck flask equipped with a stirrer, a thermometer and a nitrogen reflux tube, and then 220 parts by mass of polycarbonate polyol-3 (starting from 1, 6-hexanediol and having a number average molecular weight of 2000), 12 parts by mass of 2, 2-dimethylolpropionic acid and 70 parts by mass of dicyclohexylmethane diisocyanate were added and reacted at 70 ℃ for 1 hour to obtain a methyl ethyl ketone solution of a urethane prepolymer.
Next, 4.5 parts by mass of piperazine and 9 parts by mass of triethylamine were mixed in this methyl ethyl ketone solution of the urethane prepolymer, and 880 parts by mass of ion-exchanged water was added to obtain an emulsion in which the urethane resin (B-2) was dispersed in water.
Then, methyl ethyl ketone was distilled off from the above emulsion, and ion-exchanged water was further added to obtain an aqueous dispersion of urethane resin (B-2) having a nonvolatile content of 32 mass%.
The obtained urethane resin (B-2) had a urethane bond content of 1278mmol/kg, a urea bond content of 435mmol/kg and an alicyclic structure content of 1713 mmol/kg.
Synthesis example 5 preparation of aqueous Dispersion of urethane resin (B-3)
250 parts by mass of methyl ethyl ketone and 0.001 part by mass of stannous octoate were charged into a four-neck flask equipped with a stirrer, a thermometer and a nitrogen reflux tube, and then 138 parts by mass of polycarbonate polyol-4 (1, 6-hexanediol was used as a raw material, and the number average molecular weight: 2000), 55 parts by mass of polycarbonate polyol-5 (1, 6-hexanediol was used as a raw material, and the number average molecular weight: 500), 13 parts by mass of 2, 2-dimethylolpropionic acid, and 100 parts by mass of dicyclohexylmethane diisocyanate were added and reacted at 70 ℃ for 1 hour to obtain a methyl ethyl ketone solution of a urethane prepolymer.
Then, 5.6 parts by mass of piperazine and 10 parts by mass of triethylamine were mixed in this methyl ethyl ketone solution of the urethane prepolymer, and 880 parts by mass of ion-exchanged water was added to obtain an emulsion in which the urethane resin (B-3) was dispersed in water.
Then, methyl ethyl ketone was distilled off from the above emulsion, and ion-exchanged water was further added to obtain an aqueous dispersion of urethane resin (B-3) having a nonvolatile content of 30 mass%.
The obtained urethane resin (B-3) had a urethane bond content of 1747mmol/kg, a urea bond content of 576mmol/kg, and an alicyclic structure content of 2341 mmol/kg.
[ example 1]
A urethane resin composition was obtained by mixing 15 parts by mass of the aqueous urethane resin (A-1) dispersion obtained in Synthesis example 1, 15 parts by mass of the aqueous urethane resin (B-1) dispersion obtained in Synthesis example 3, 3 parts by mass of a carbodiimide crosslinking agent ("V-02-L2" manufactured by Nisshinbo chemical Co., Ltd.), 2 parts by mass of a filler ("ACEMATT TS 100" manufactured by EVONIK DEGUSSA, silica particles having an average particle diameter of 10 μm manufactured by a dry method, and 65 parts by mass of water.
[ example 2]
A urethane resin composition was obtained by mixing 25 parts by mass of the aqueous urethane resin (A-1) dispersion obtained in Synthesis example 1, 5 parts by mass of the aqueous urethane resin (B-1) dispersion obtained in Synthesis example 3, 3 parts by mass of a carbodiimide crosslinking agent ("V-02-L2" manufactured by Nisshinbo chemical Co., Ltd.), 2 parts by mass of a filler ("ACEMATT TS 100" manufactured by EVONIK DEGUSSA, silica particles having an average particle diameter of 10 μm manufactured by a dry method, and 65 parts by mass of water.
[ example 3]
A urethane resin composition was obtained by mixing 5 parts by mass of the aqueous urethane resin (A-1) dispersion obtained in Synthesis example 1, 25 parts by mass of the aqueous urethane resin (B-1) dispersion obtained in Synthesis example 3, 3 parts by mass of a carbodiimide crosslinking agent ("V-02-L2" manufactured by Nisshinbo chemical Co., Ltd.), 2 parts by mass of a filler ("ACEMATT TS 100" manufactured by EVONIK DEGUSSA, silica particles having an average particle diameter of 10 μm manufactured by a dry method, and 65 parts by mass of water.
[ example 4]
A urethane resin composition was obtained by mixing 15 parts by mass of the aqueous urethane resin (A-2) dispersion obtained in Synthesis example 1, 15 parts by mass of the aqueous urethane resin (B-2) dispersion obtained in Synthesis example 3, 3 parts by mass of a carbodiimide crosslinking agent ("V-02-L2" manufactured by Nisshinbo chemical Co., Ltd.), 2 parts by mass of a filler ("ACEMATT TS 100" manufactured by EVONIK DEGUSSA Co., Ltd., silica particles having an average particle diameter of 10 μm produced by a dry method) and 65 parts by mass of water.
[ example 5]
A urethane resin composition was obtained by mixing 5 parts by mass of the aqueous urethane resin (A-2) dispersion obtained in Synthesis example 1, 25 parts by mass of the aqueous urethane resin (B-2) dispersion obtained in Synthesis example 3, 3 parts by mass of a carbodiimide crosslinking agent ("V-02-L2" manufactured by Nisshinbo chemical Co., Ltd.), 2 parts by mass of a filler ("ACEMATT TS 100" manufactured by EVONIK DEGUSSA, silica particles having an average particle diameter of 10 μm manufactured by a dry method, and 65 parts by mass of water.
[ example 6]
A urethane resin composition was obtained by mixing 15 parts by mass of the aqueous urethane resin (A-1) dispersion obtained in Synthesis example 1, 15 parts by mass of the aqueous urethane resin (B-3) dispersion obtained in Synthesis example 3, 3 parts by mass of a carbodiimide crosslinking agent ("V-02-L2" manufactured by Nisshinbo chemical Co., Ltd.), 2 parts by mass of a filler ("ACEMATT TS 100" manufactured by EVONIK DEGUSSA corporation, silica particles having an average particle diameter of 10 μm manufactured by a dry method, and 65 parts by mass of water.
Comparative example 1
A urethane resin composition was obtained by mixing 30 parts by mass of the aqueous urethane resin (A-1) dispersion obtained in Synthesis example 1, 3 parts by mass of a carbodiimide crosslinking agent ("V-02-L2" manufactured by Nisshinbo chemical Co., Ltd.), 2 parts by mass of a filler ("ACEMATT TS 100" manufactured by EVONIK DEGUSSA Co., Ltd., silica particles having an average particle diameter of 10 μm manufactured by a dry method) and 65 parts by mass of water.
Comparative example 2
A urethane resin composition was obtained by mixing 30 parts by mass of the aqueous urethane resin (B-1) dispersion obtained in Synthesis example 3, 3 parts by mass of a carbodiimide crosslinking agent ("V-02-L2" manufactured by Nisshinbo chemical Co., Ltd.), 2 parts by mass of a filler ("ACEMATT TS 100" manufactured by EVONIK DEGUSSA, average particle diameter: 10 μm) and 65 parts by mass of water.
[ method for measuring number average molecular weight ]
The number average molecular weight of the polyol used in the synthesis examples is a value measured by a Gel Permeation Chromatography (GPC) method under the following conditions.
A measuring device: high-speed GPC apparatus (HLC-8220 GPC, manufactured by Tosoh corporation)
A chromatographic column: the following columns manufactured by Tosoh corporation were used in series.
"TSKgel G5000" (7.8 mmI.D.. times.30 cm). times.1 roots
"TSKgel G4000" (7.8mm I.D.. times.30 cm). times.1 roots
"TSKgel G3000" (7.8 mmI.D.. times.30 cm). times.1 roots
"TSKgel G2000" (7.8 mmI.D.. times.30 cm). times.1 roots
A detector: RI (differential refractometer)
Column temperature: 40 deg.C
Eluent: tetrahydrofuran (THF)
Flow rate: 1.0 mL/min
Injection amount: 100 μ L (tetrahydrofuran solution with a sample concentration of 0.4% by mass)
Standard sample: calibration curves were prepared using the standard polystyrene described below.
(Standard polystyrene)
TSKgel Standard polystyrene A-500 manufactured by Tosoh corporation "
TSKgel Standard polystyrene A-1000 manufactured by Tosoh corporation "
TSKgel Standard polystyrene A-2500 manufactured by Tosoh corporation "
TSKgel Standard polystyrene A-5000 manufactured by Tosoh corporation "
TSKgel Standard polystyrene F-1 manufactured by Tosoh corporation "
TSKgel Standard polystyrene F-2 manufactured by Tosoh corporation "
TSKgel Standard polystyrene F-4 manufactured by Tosoh corporation "
TSKgel Standard polystyrene F-10 manufactured by Tosoh corporation "
TSKgel Standard polystyrene F-20 manufactured by Tosoh corporation "
TSKgel Standard polystyrene F-40 manufactured by Tosoh corporation "
TSKgel Standard polystyrene F-80 manufactured by Tosoh corporation "
TSKgel Standard polystyrene F-128 manufactured by Tosoh corporation "
TSKgel Standard polystyrene F-288 manufactured by Tosoh corporation "
TSKgel Standard polystyrene F-550 manufactured by Tosoh corporation "
[ method for measuring acid value of urethane resin (A) ]
The aqueous dispersion of the urethane resin (a) obtained in the synthesis example was dried, 0.05g to 0.5g of the dried and cured resin particles were weighed into a 300mL Erlenmeyer flask, and then about 80mL of a mixed solvent having a mass ratio of tetrahydrofuran to ion-exchange water [ tetrahydrofuran/ion-exchange water ] of 80/20 was added to obtain a mixed solution thereof.
Then, a phenolphthalein indicator was mixed with the mixed solution, and the mixture was titrated with a previously prepared 0.1mol/L aqueous potassium hydroxide solution, and the acid value (mgKOH/g) of the urethane resin (A) was determined from the amount of the aqueous potassium hydroxide solution used for the titration according to the following calculation formula (1-1-1).
Calculation formula a ═ (B × f × 5.611)/S (1-1-1)
Wherein A is the solid acid value (mgKOH/g) of the resin, B is the amount (mL) of a 0.1mol/L aqueous potassium hydroxide solution used for titration, f is a factor of the 0.1mol/L aqueous potassium hydroxide solution, S is the mass (g) of the resin particles, and 5.611 is the formula weight (56.11/10) of potassium hydroxide.
[ evaluation method of squeak and coefficient of dynamic Friction ]
The urethane resin compositions obtained in examples and comparative examples were coated on a PVC sheet using a 50 μm bar coater, and dried at 120 ℃ for 2 minutes in a driving oven (Japanese: ギア Only, ーブン) to obtain samples for evaluation. The evaluation samples were evaluated for the risk of occurrence of abnormal noise and the coefficient of dynamic friction under the conditions of a load of 40N, a moving speed of 1 mm/sec and a moving speed of 10 mm/sec for each of the sheets using a stick-slip tester ("SSP-4" manufactured by Ziegler Co.).
(crunchy sound)
"T"; the risk of abnormal sound is 1-3.
"F"; the risk of abnormal sound occurrence is 4 or more.
The risk of abnormal sound is marked in the corresponding color; the risk of occurrence of stick-slip abnormal noise when the contact member was made of 2 materials was evaluated by using 10-grade indices according to the method of the German Association for automotive industries.
1-3; no stick-slip risk (without stick-slip risk)
4-5; medium-stick slip risk (Medium stick slip risk)
6-10; high-stick slip risk (high risk of sliminess)
(coefficient of dynamic Friction)
"T"; 0.2 or more
"F"; less than 0.2
[ Table 1]
TABLE 1
|
Example 1
|
Example 2
|
Example 3
|
Example 4
|
Urethane resin (A)
|
(A-1)
|
(A-1)
|
(A-1)
|
(A-2)
|
Urethane resin (B)
|
(B-1)
|
(B-1)
|
(B-1)
|
(B-2)
|
(A) V (B) mass ratio
|
50/50
|
83/17
|
17/83
|
50/50
|
Evaluation of squeak
|
T
|
T
|
T
|
T
|
Evaluation of coefficient of dynamic Friction
|
T
|
T
|
T
|
T |
[ Table 2]
TABLE 2
|
Example 5
|
Example 6
|
Comparative example 1
|
Comparative example 2
|
Urethane resin (A)
|
(A-2)
|
(A-1)
|
(A-1)
|
|
Urethane resin (B)
|
(B-2)
|
(B-3)
|
|
(B-1)
|
(A) V (B) mass ratio
|
83/17
|
50/50
|
100/0
|
0/100
|
Evaluation of squeak
|
T
|
T
|
T
|
F
|
Evaluation of coefficient of dynamic Friction
|
T
|
T
|
F
|
T |
It is found that the urethane resin composition of the present invention can provide a coating film having low squeak noise and a high coefficient of dynamic friction.
On the other hand, comparative example 1 was an embodiment not containing the urethane resin (B), and had a low coefficient of dynamic friction.
Comparative example 2 was an embodiment not including the urethane resin (a), and the risk of occurrence of abnormal noise by the stick-slip test apparatus was 7, which was not effective in reducing squeak noise.