Polyurea resin composition, method for producing the same, and raw material for production of two-component mixed polyurea resin composition

Abstract

To provide a polyurea resin composition that is free from solvent, has good curing time in casting applications, offers superior water resistance and chemical resistance in the form of coating films, and further provides excellent hardness.SOLUTION: A polyurea resin composition comprises a polyisocyanate compound (A) and a polyamine compound (B), wherein the polyisocyanate compound (A) contains 50 mass% or more of an alicyclic isocyanate or a derivative thereof (A'), and the polyamine compound (B) contains a polyamine compound (B') having a cyclic structure without an ester bond.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a polyurea resin composition, a method for producing the same, and raw materials for producing a two-component mixed polyurea resin composition. [Background technology]

[0002] Two-component curing polyurea resin compositions, which are composed of two components, a polyisocyanate and a curing agent containing a polyamine, cure at room temperature, and the resulting cured polyurea resin has excellent mechanical strength.

[0003] Polyurea resin compositions obtained by mixing an aliphatic polyisocyanate base resin with an aliphatic polyamine curing agent have a problem in that the curing reaction begins immediately after the start of mixing the two liquids, making it difficult to ensure a sufficient time for molding (usable life).To address this problem, a method has been reported in which bis(N-alkylaminocyclohexyl)methane, a secondary aliphatic diamine in which the amino group is substituted with a bulky alkyl group, is used as a curing agent (Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 2759053 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the polyurea resin composition disclosed in Patent Document 1 requires further improvement in hardness and water and chemical resistance in order to be used as a protective coating (coating film) for molded articles. In addition, the curing time is too long, making it unsuitable for use in casting.

[0006] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a polyurethane resin composition which is excellent in water resistance and chemical resistance, can form a coating film with excellent hardness, and has a satisfactory curing time suitable for use in casting even in the absence of a solvent. [Means for solving the problem]

[0007] As a result of extensive research, the present inventors have found that by using a polyisocyanate compound and a polyamine compound having a specific structure, hardness and water resistance and chemical resistance can be improved, and a sufficient curing time can be ensured even without solvent, thereby solving the above-mentioned problems, and have completed the present invention. That is, the gist of the present invention is as follows.

[0008] [1] A polyurea resin composition containing a polyisocyanate compound (A) and a polyamine compound (B), wherein the polyisocyanate compound (A) contains 50 mass% or more of an acyclic isocyanate or a derivative thereof (A'), and the polyamine compound (B) contains a polyamine compound (B') having a cyclic structure containing no ester bond. [2] The polyurea resin composition according to [1], wherein the polyamine compound (B') satisfies the following (a) or (b): (a) Hexasubstituted benzene with two or more primary amino groups. (b) A compound represented by the following general formula (1): R 1 -(NH)-R 2 -(NH)-R 3 (1) (R 1 , R 3 are each independently an alkyl group, R 2 represents an organic group having a cyclic structure) [3] The polyurea resin composition according to [2], wherein the polyamine compound (B') satisfies the following condition (c) or (d): (c) Hexasubstituted benzene containing two or more primary amino groups and containing halogen (d) A compound represented by the following general formula (2): R 1´-(NH)-R 2 ´-(NH)-R 3 ´ (2) (R 1 ´,R 3 ´ are each independently an alkyl group having 2 to 14 carbon atoms, R 2 ´ is an organic group having a ring structure and 6 to 20 carbon atoms) [4] The polyurea resin composition according to any one of [1] to [3], wherein the proportion of the polyamine compound (B') in the polyamine compound (B) is 30 mass % or more. [5] The polyurea resin composition according to any one of [1] to [4], wherein the polyamine compound (B') has a number average molecular weight of 100 to 5,000 and an amine value of 20 to 1200 mgKOH / g. [6] The polyurea resin composition according to any one of [1] to [5], wherein the polyisocyanate compound (A) has an isocyanate group content of 5 to 50 NCO %. [7] The polyurea resin composition according to any one of [1] to [6], wherein the viscosity measured with a Brookfield viscometer at 25°C immediately after mixing all components including the polyisocyanate compound (A) and the polyamine compound (B) under solvent-free conditions is 100 to 50,000 mPa s. [8] A coating film comprising the polyurea resin composition according to any one of [1] to [7]. [9] A cast-molded article made from the polyurea resin composition according to any one of [1] to [7].

[10] A method for producing a polyurea resin composition according to any one of [1] to [7], A production method comprising mixing a polyisocyanate compound (A) containing 50 mass% or more of an acyclic aliphatic isocyanate or a derivative thereof (A') with a polyamine compound (B) containing a polyamine compound (B') having a cyclic structure containing no ester bond.

[11] A raw material for producing a two-component mixed polyurea resin composition containing a polyisocyanate compound (A) and a polyamine compound (B), The polyisocyanate compound (A) contains 50 mass% or more of an acyclic aliphatic isocyanate or a derivative thereof (A'), A raw material for producing a two-component mixed polyurea resin composition, wherein the polyamine compound (B) contains a polyamine compound (B') having a cyclic structure containing no ester bond. [Effects of the Invention]

[0009] The polyurea resin composition of the present invention can provide a solvent-free polyurea resin composition that has a good curing time suitable for use in casting, and when formed into a coating film, has excellent water resistance and chemical resistance, and is also excellent in hardness. DETAILED DESCRIPTION OF THE INVENTION

[0010] The polyurea resin composition of the present invention contains a polyisocyanate compound (A) and a polyamine compound (B). <Polyisocyanate compound (A)> The polyisocyanate compound (A) constituting the resin composition of the present invention is a compound having two or more isocyanate groups in one molecule, and may be in the form of a monomer, oligomer, or polymer, and may be modified with a chain extender such as a polyol component.

[0011] The polyisocyanate compound (A) in the present invention must contain 50 mass % or more of the acyclic aliphatic isocyanate or its derivative (A'), more preferably 75 mass % or more, even more preferably 80 mass % or more, and particularly preferably 100 mass %. When the content of the acyclic aliphatic isocyanate or its derivative (A') is 50 mass % or more, the polyisocyanate compound (A) can achieve a good curing time suitable for, for example, hand-applied paint applications and cast molding applications.

[0012] The acyclic aliphatic polyisocyanate compound is not particularly limited, but examples thereof include 1,6-hexamethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,5-pentamethylene diisocyanate, 2-methylpentane-1,5-diisocyanate, 3-methylpentane-1,5-diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisocyanate methylcaproate, lysine diisocyanate, trioxyethylene diisocyanate, etc. These may be used alone or in combination of two or more.

[0013] Examples of the derivatives of acyclic aliphatic polyisocyanate compounds include isocyanate-terminated prepolymers obtained by reacting an aliphatic polyisocyanate compound with a polyamine or polyol, allophanate-modified products, urea-modified products, carbodiimide-modified products, biuret-modified products, uretdione-modified products, isocyanurate-modified products, and water-dispersible modified products. When the polyisocyanate compound (A) contains a derivative of hexamethylene diisocyanate such as an isocyanate-terminated prepolymer or modified product, the properties of the resulting coating film, such as chemical resistance, are improved.

[0014] Among these, hexamethylene diisocyanate (HDI) and its derivatives are preferred. Hexamethylene diisocyanate derivatives can be obtained by known methods.

[0015] The polyisocyanate compound (A) may contain, in addition to the acyclic aliphatic polyisocyanate and its derivatives, other isocyanate components depending on the desired performance such as physical properties and curing time (pot life). These are not particularly limited, but examples include isophorone diisocyanate, 1,4-bis(isocyanatomethyl)cyclohexane, 4,4'-methylenebis(cyclohexylisocyanate), methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, 1,3-bis(isocyanatoethyl)cyclohexane, 1,4-bis(isocyanatoethyl)cyclohexane, 2,5- or 2,6-bis(isocyanatomethyl)norbornane (NBDI), 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, 1,5-naphthylene diisocyanate, and hydrogenated aromatic polyisocyanates.

[0016] When HDI is used as the acyclic aliphatic polyisocyanate, the isocyanate component other than HDI is not particularly limited, but from the viewpoint of compatibility with HDI, for example, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, diphenylmethane diisocyanate (MDI), xylylene diisocyanate, 1,5-naphthylene diisocyanate, 1,5-pentamethylene diisocyanate, and 4,4'-methylenebis(cyclohexyl isocyanate) are preferred, and 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, diphenylmethane diisocyanate, and 1,5-pentamethylene diisocyanate are more preferred. Two or more of these may also be used in combination. Furthermore, as these isocyanate components, isocyanate-terminated prepolymers, allophanate-modified products, urea-modified products, carbodiimide-modified products, biuret-modified products, uretdione-modified products, isocyanurate-modified products, and those modified into water-dispersible types can also be used.

[0017] The isocyanate group content in the polyisocyanate compound (A) is preferably 5 to 50 NCO%, more preferably 5 to 35 NCO%, even more preferably 10 to 33 NCO%, and particularly preferably 15 to 30 NCO%. A polyurea resin composition containing a polyisocyanate compound (A) with an isocyanate group content higher than the above range may fail to provide a coating film with sufficient physical properties, and if the isocyanate group content in the polyisocyanate compound (A) is lower than the above range, the resin composition may fail to ensure a satisfactory curing time.

[0018] The viscosity of the polyisocyanate compound (A) measured with a Brookfield viscometer is preferably 500 to 30,000 mPa·s, more preferably 500 to 25,000 mPa·s, and even more preferably 800 to 20,000 mPa·s at 25°C. A coating material made from a resin composition containing a polyisocyanate compound (A) with a viscosity of more than 30,000 mPa·s at 25°C may require a long time to mix uniformly with other materials or may be difficult to apply uniformly. On the other hand, a coating material made from a polyisocyanate compound (A) with a viscosity of less than 500 mPa·s may sag when applied to a wall, preventing the formation of a uniform coating film.

[0019] <Polyamine Compound B> The polyamine compound (B) in the present invention must contain a polyamine compound (B') having a cyclic structure containing no ester bonds. The content is preferably 30% by mass or more, more preferably 50% by mass or more, even more preferably 80% by mass or more, and particularly preferably 100% by mass. By including the polyamine compound (B') having a cyclic structure containing no ester bonds in the polyamine compound (B), the hardness and water resistance / chemical resistance of the resulting coating film are improved.

[0020] Examples of the polyamine compound (B') include 1,2- or 1,4-cyclohexanediamine, o-, m- or p-phenylenediamine, 2,5-diaminotoluene, 2,5-diamino-p-xylene, 2,3,5,6-tetramethyl-p-phenylenediamine, 5-chloro-2,4,diethyl-6-methylbenzene-1,3-diamine, 5-chloro-4,6-diethyl-2-methylbenzene-1,3-diamine, 1,5-naphthalenediamine, 1,8-naphthalenediamine, N,N'-dimethylcyclohexanedi ... 4,4'-methylenebis(N-sec-butylcyclohexaneamine), bis(4-aminophenyl)methane, bis(n-sec-butyl-4-amino-3-methylcyclohexyl)methane, 4,4'-methylenebis(N-sec-butylaniline), and the like.

[0021] Among these, from the viewpoint of improving the hardness of the resulting coating film, the polyamine compound (B') is preferably a hexasubstituted benzene containing two or more primary amino groups, such as 2,3,5,6-tetramethyl-p-phenylenediamine, 5-chloro-2,4-diethyl-6-methylbenzene-1,3-diamine, or 5-chloro-4,6-diethyl-2-methylbenzene-1,3-diamine, or a compound represented by the following general formula (1), such as N,N'-dimethylcyclohexane-1,2-diamine, N,N'-dimethyl-o-phenylenediamine, N,N'-di-sec-butyl-p-phenylenediamine, 4,4'-methylenebis(N-sec-butylcyclohexanamine), bis(n-sec-butyl-4-amino-3-methylcyclohexyl)methane, or 4,4'-methylenebis(N-sec-butylaniline). R 1 -(NH)-R 2 -(NH)-R 3 (1) (R 1 ,R 3 is an alkyl group, R 2is an organic group having a cyclic structure)

[0022] More preferred are hexasubstituted benzenes containing two or more primary amino groups and containing halogen, such as 5-chloro-2,4,diethyl-6-methylbenzene-1,3-diamine and 5-chloro-4,6-diethyl-2-methylbenzene-1,3-diamine, or compounds represented by the following general formula (2), such as N,N'-di-sec-butyl-p-phenylenediamine, 4,4'-methylenebis(N-sec-butylcyclohexanamine), bis(n-sec-butyl-4-amino-3-methylcyclohexyl)methane, and 4,4'-methylenebis(N-sec-butylaniline). R 1 ´-(NH)-R 2 ´-(NH)-R 3 ´ (2) (R 1 ´,R 3 ' are each independently an alkyl group having 2 to 14 carbon atoms, R 2 ´ is an organic group having a ring structure and 6 to 20 carbon atoms)

[0023] Commercially available polyamine compounds (B') having a cyclic structure that does not contain an ester bond include, for example, "Primacure P-25i" manufactured by Arxada, and "Clearlink 1000," "Unilink 4100," and "Unilink 4200" manufactured by Dorfketal.

[0024] The polyamine compound (B) may contain other polyamine components in addition to the polyamine compound (B') having a cyclic structure containing no ester bond, depending on the desired performance such as coating film properties and curing time (pot life).

[0025] Other amine compounds include polyamine compounds without a cyclic structure, such as hexamethylenediamine and nonanediamine, and polyamine compounds containing an ester bond, such as polyalkyleneoxide-di-p-aminobenzoate and 4,4'-(methylene)bis(cyclohexane-1-amine)-N,N'-[methylenebis(cyclohexane-4,1-diyl)]bis(diethyl aspartate). The other amine compounds can be either primary or secondary amines.

[0026] The number average molecular weight of the polyamine compound (B') is not particularly limited, but is preferably 100 to 5000, more preferably 100 to 3000, further preferably 100 to 2000, and particularly preferably 100 to 1000. If the molecular weight of the polyamine compound (B') is less than 100, the resin composition may have a short pot life, and if the number average molecular weight exceeds 5000, the hardness of the resulting coating film may be poor.

[0027] The amine value of the polyamine compound (B') is not particularly limited, but is preferably 20 to 1200 mgKOH / g, more preferably 40 to 1200 mgKOH / g, even more preferably 60 to 1200 mgKOH / g, and particularly preferably 100 to 1000 mgKOH / g. If the amine value of the polyamine compound (B') is less than 20 mgKOH / g, the coating film properties such as hardness may be poor, and if it exceeds 1200 mgKOH / g, the pot life may be poor.

[0028] <Other ingredient C> The polyamine compound (B) may contain a liquid resin having a functional group other than an amino group that reacts with an isocyanate group, as long as the effect of the invention is not impaired. The type of liquid resin is not particularly limited, but examples include polyol resins, epoxy resins, polyester resins, polyolefin resins, polyamide resins, polycarboxylic acid resins, methacrylic resins, vinyl ester resins, and polyurethane resins. Among these, polyol resins are preferred from the viewpoint of ensuring a good curing time.

[0029] The content of the other component (C) in the polyamine compound (B) is preferably 20% by mass or less, more preferably 10% by mass or less, and particularly preferably 5% by mass or less. If the content of the other component (C) exceeds 20% by mass, the polyurea resin composition may not have a satisfactory curing time.

[0030] The number average molecular weight of the other component (C) is not particularly limited, but is preferably 100 to 10,000, more preferably 200 to 5,000, even more preferably 300 to 3,000, and particularly preferably 500 to 2,000. If the molecular weight of the other component (C) is less than 100, the resin composition may have a short usable life, and if the number average molecular weight exceeds 5,000, the hardness of the resulting coating film may be poor.

[0031] The viscosity of the other component (C), measured with a Brookfield viscometer, at 25°C is preferably 100 to 30,000 mPa·s, more preferably 300 to 20,000 mPa·s, and even more preferably 500 to 10,000 mPa·s. A paint made from a resin composition containing another component (C) with a viscosity of more than 30,000 mPa·s at 25°C may take a long time to mix uniformly with other materials or may be difficult to apply uniformly. On the other hand, a paint with a viscosity of less than 100 mPa·s may sag when applied to a wall, preventing the formation of a uniform coating film.

[0032] <Polyurea resin composition> In the resin composition of the present invention, the equivalent ratio (isocyanate groups (mol) / amino groups (mol)) of the isocyanate groups of the polyisocyanate compound (A) to the amino groups of the polyamine compound (B) is preferably 0.5 to 1.7, more preferably 0.6 to 1.5, even more preferably 0.7 to 1.4, and particularly preferably 0.8 to 1.3. Furthermore, when the polyamine compound (B) contains other component (C), the total amount of amino groups and active hydrogen groups is used instead of the amount of amino groups. If the equivalent ratio is less than 0.5 or more than 1.7, the resulting coating film may not be cured or may exhibit reduced physical properties such as hardness and chemical resistance.

[0033] The polyurea resin composition of the present invention preferably has a viscosity at 25°C immediately after mixing (e.g., 30 seconds after mixing) all of the components, including the polyisocyanate compound (A) and the polyamine compound (B), under solvent-free conditions of 100 to 50,000 mPa·s, more preferably 200 to 30,000 mPa·s, and even more preferably 300 to 15,000 mPa·s. If the resin composition has a viscosity of less than 100 mPa·s, it may be difficult to obtain a coating film with sufficient thickness, and if it exceeds 50,000 mPa·s, workability during application may be reduced.

[0034] The polyurea resin composition of the present invention may contain a catalyst in order to improve the physical properties of the resulting coating film and to adjust the usable time and curing temperature. Specific examples of catalysts include tertiary amines such as triethylamine, tributylamine, triethylenediamine, 2-dimethylaminoethyl ether, diazabicycloundecene, and N-methylmorpholine; metal catalysts such as dibutyltin diacetate, dibutyltin laurate, 3-diacetoxytetrabutylstannoxane, tin octenoate, tin chloride, butyl tin trichloride, bismuth trichloride, bismuth octenoate, tetrakis(2-ethylhexyl)titanate, tetrabutoxytitanium, and metal salts of acetoacetic acid; and quaternary ammonium salts.

[0035] The polyurea resin composition of the present invention may contain additives as needed. Examples of additives include silica, basic inorganic salts, pH adjusters, metal oxide fine particles, tackifiers, waxes, UV absorbers, leveling agents, wetting agents, antifoaming agents, anti-popping agents, anti-sagging agents, paint spread improvers, thixotropy-imparting agents, pigments, dyes, dispersants, diluents, and fillers. These may be used alone or in combination of two or more. The additives may also be added to the polyisocyanate compound (A) or the polyamine compound (B) in advance. The amount of the additive to be added can be determined appropriately depending on the purpose.

[0036] The polyurea resin composition of the present invention may contain other resins as needed, such as melamine resins, epoxy resins, polyurethane resins, polyester resins, and polyolefin resins.

[0037] In addition, the polyurea resin composition of the present invention can use a common organic solvent as a diluent, as long as it is not reactive with the polyisocyanate compound (A). Examples of organic solvents that can be used as diluents include hydrocarbon compounds such as toluene, xylene, and cyclohexane, carbonyl compounds such as acetone, 2-butanone, and isophorone, and ester compounds such as ethyl acetate and butyl acetate. These may be used alone or in combination of two or more.

[0038] The content of the organic solvent in the resin composition is preferably 10% by mass or less, more preferably 3% by mass or less, and particularly preferably 1% by mass or less. If the content of the organic solvent in the resin composition exceeds 10% by mass, not only may the physical properties of the resulting coating film be reduced, but also the inherent advantage of the polyurea resin, that it can be produced without a solvent, may be lost.

[0039] <Application> The polyurea resin composition of the present invention can be used to form coating films as a primer, intermediate coat, or top coat on materials such as metals such as iron plates and steel plates, plastics, films, sheets, ceramics, glass, concrete, fibers, and paper by roll coating, curtain flow coating, spray coating, electrostatic coating, bell coating, immersion, roller coating, brush coating, gravure printing, or the like, or can be used as a sizing agent, reinforcing material, or the like.

[0040] The polyurea resin composition of the present invention can be suitably used to impart aesthetic appearance, weather resistance, water resistance, chemical resistance, rust prevention, abrasion resistance, adhesion, and the like to the above-mentioned materials. The polyurea resin composition of the present invention is also useful as an adhesive, a pressure sensitive adhesive, an elastomer, a foam, a surface treatment agent, and the like.

[0041] The polyurea resin composition of the present invention is suitable for hand application because it can ensure a sufficient curing time, and can be used as a paint to form a coating film as described above. In addition, because it can ensure a sufficient curing time, it can also be poured into a metal frame to produce a molded product (cast molded product).

[0042] The polyurea resin composition of the present invention is reactive at room temperature and therefore does not usually require heating, but may be heated to accelerate curing after coating, etc., or to improve low-temperature working environments in winter, etc. The curing temperature can be appropriately determined based on the application method and curing time, and is preferably 30 to 80°C from the viewpoint of safety.

[0043] As a device for heating the resin composition of the present invention, a known device can be used, taking into consideration the viscosity of the resulting polyurethane resin, the shape of the adherend, etc. Specific examples of the heating device include a heating roller, a roller heater, a polyimide heater, an infrared radiation heater, a high-temperature air heater, a heat gun, a dryer, a drying oven, a baking oven, a constant-temperature dryer, a constant-temperature oven, etc.

[0044] <Production of Polyurea Resin Composition> The method for producing the polyurea resin composition of the present invention involves mixing a polyisocyanate compound (A) containing 50 mass% or more of an acyclic aliphatic isocyanate or its derivative (A') with a polyamine compound (B) containing a polyamine compound (B') having a cyclic structure containing no ester bond. A known or commonly used method can be used for the mixing. During mixing, any of the above-mentioned optional components may be blended, if necessary.

[0045] <Raw materials for manufacturing two-component mixed polyurea resin composition> The raw material for producing a two-component mixed polyurea resin composition of the present invention contains a polyisocyanate compound (A) and a polyamine compound (B). The polyisocyanate compound (A) contains 50 mass% or more of an acyclic aliphatic isocyanate or a derivative thereof (A'), and the polyamine compound (B) contains a polyamine compound (B') having a cyclic structure containing no ester bond. The raw material for producing a two-component mixed polyurea resin composition of the present invention may contain any of the above-mentioned optional components, as necessary. [Example]

[0046] The present invention will be explained in more detail with reference to examples and comparative examples, but the present invention is not limited to the following examples in any way. In the examples and comparative examples, the following raw materials were used as they were without purification or distillation.

[0047] <Polyisocyanate compound (A)> <Hexamethylene diisocyanate or its derivative (A')> A´1: 1,6-hexamethylene diisocyanate (Tokyo Chemical Industry Co., Ltd., isocyanate group content 49.9% by mass, viscosity 3 mPa·s) A'2: Biuret-modified hexamethylene diisocyanate (Asahi Chemical Industry Co., Ltd. "Duranate 24A-100", isocyanate group content 23.5% by mass, viscosity 1,800 mPa s) A'3: Nurate-modified hexamethylene diisocyanate (Tosoh Corporation's "Coronate HXR," isocyanate group content 21.9% by mass, viscosity 1,700 mPa·s) A'4: Water-dispersible hexamethylene diisocyanate (Asahi Chemical Industry Co., Ltd. "Duranate WL72-100", isocyanate group content 21.3% by mass, viscosity 1,000 mPa·s)

[0048] A'5: Isocyanate-terminated HDI prepolymer (isocyanate group content 20.5% by mass, viscosity 2,000 mPa·s) synthesized by the following method A nitrogen atmosphere was created inside a four-necked flask equipped with a stirrer, a thermometer, a reflux condenser, a nitrogen inlet tube, and a dropping funnel, and 100 parts by mass of hexamethylene diisocyanate (HDI) and 21.5 parts by mass of polypropylene glycol (number average molecular weight 750) were charged. The temperature inside the reactor was maintained at 95°C for 90 minutes with stirring to carry out a urethanization reaction. The cooled reaction liquid was filtered and unreacted HDI was removed using a thin-film evaporator, yielding an isocyanate-terminated HDI prepolymer with an isocyanate group content of 20.5% by mass, a viscosity of 3,000 mPa·s at 25°C, and a number-average molecular weight of 1,520.

[0049] <Other polyisocyanate compounds (A´´)> A´´1: Isophorone diisocyanate (isomer mixture) (Tokyo Chemical Industry Co., Ltd., isocyanate group content 37.8% by mass, viscosity 10 mPa·s) A´´2: Polymeric MDI (Tosoh Corporation's "Millionate MR-200", isocyanate group content 30.9% by mass, viscosity 150 mPa·s) A´´3: Isophorone diisocyanate derivative (Convestro "Desmodur Z-4370", isocyanate group content 18.9%, viscosity 600 mPa·s)

[0050] <Polyamine compound (B)> <Polyamine compound (B') having a cyclic structure containing no ester bond> B´1: Mixture of 5-chloro-2,4,diethyl-6-methylbenzene-1,3-diamine and 5-chloro-4,6-diethyl-2-methylbenzene-1,3-diamine (Arxada "Primacure P-25i", amine value 528 mg KOH / g, viscosity 17,260 mPa·s) B´2: 4,4´-methylenebis(N-sec-butylcyclohexanamine) (Dorfketal "Clearlink 1000", amine value 348 mg KOH / g, viscosity 62 mPa·s) B´3: 4.4´-methylenebis(N-sec-butylaniline) (Dorfketal "Unilink 4200", amine value 362 mg KOH / g, viscosity 324 mPa s) B´4: N,N´-di-sec-butyl-p-phenylenediamine (Dorfketal "Unilink 4100", amine value 572 mg KOH / g, viscosity 20 mPa s)

[0051] B´5: Bis(n-sec-butyl-4-amino-3-methylcyclohexyl)methane (amine value 322 mg KOH / g, viscosity 80 mPa·s) synthesized by the following method: Bis(4-amino-3-methylcyclohexyl)methane was synthesized by reductive alkylation with methyl ethyl ketone in the presence of hydrogen over a 0.375% platinum on alumina catalyst.

[0052] <Other polyamine compounds B´´> B´´1: Aspartic acid ester compound (Feiyang "Feispartic F420", amine value 203 mg KOH / g, viscosity 1,450 mPa s) B´´2: Polytetramethylene oxide-di-p-aminobenzoate (Kumiai Chemical Industry Co., Ltd. "Elasmer 250P", amine value 221 mg KOH / g, viscosity 154 mPa·s (85°C)) B´´3: Polytetramethylene oxide-di-p-aminobenzoate (Kumiai Chemical Industry Co., Ltd. "Elasmer 650P", amine value 126 mg KOH / g, viscosity 1,470 mPa·s (40°C))

[0053] <Other components: Polyol compound (C)> C1: Glycerin-propylene oxide adduct (ADEKA "G-700", hydroxyl value 224 mg KOH / g, viscosity 230 mPa·s) C2: Glycerin-propylene oxide adduct (ARCO Chemical Co., Ltd. "LG-168", hydroxyl value 200 mg KOH / g, viscosity 300 mPa·s)

[0054] The various physical properties were measured by the following evaluation methods. (1) Isocyanate group content It was determined according to the hydrochloric acid back titration method for di-n-butylamine specified in JIS K 7301.

[0055] (2) Amine value It was determined according to the indicator titration method of JIS K 7237.

[0056] (3) Equivalent ratio (amino group / hydroxy group), equivalent ratio (isocyanate group / (amino group + active hydrogen group)) It was calculated from the amount of each component in the resin composition and the isocyanate group content, amine value, and hydroxyl value of each component determined in (1) to (3) above.

[0057] (4) Viscosity All components including the polyisocyanate compound (A) and the polyamine compound (B) were quickly mixed together using a Brookfield Dial Viscometer (BROOKFIELD ENGINEERING LABORATORIES, INC.), and the rotational viscosity (mPa·s) at 25°C was measured after 30 seconds. When the viscosity was 2000 mPa·s or more, the SC4-8R viscometer and the SC4-16 spindle were used, and when the viscosity was less than 2000 mPa·s, the SC4-13R viscometer and the SC4-18 spindle were used.

[0058] (5) Dry to touch time (curing time) All components, including the polyisocyanate compound (A) and the polyamine compound (B), were placed in a glass container (100 mL) and quickly mixed at 25°C using a metal stirrer until the mixture appeared uniform. The mixture was then poured into a mold, and the tack-free time was measured. The tack-free time was evaluated according to the following criteria. 5: Curing time is 1 minute or more and 3 minutes or less 4: Curing time is 30 seconds or more but less than 1 minute, or more than 3 minutes but less than 10 minutes 3: Curing time is between 10 and 30 seconds, or between 10 and 30 minutes 2: Curing time is less than 10 seconds, or more than 30 minutes but less than 60 minutes 1: Curing time exceeds 60 minutes 0: The material hardened too quickly to measure the hardening time, or the material did not harden even after 60 minutes from mixing. For practical purposes, the pot life must be rated "2" or higher, and "3" or higher is more preferable.

[0059] (6) Hardness The pencil hardness was determined according to the pencil method of JIS K 5600-5-4. The hardness was judged according to the following criteria: 5: Pencil hardness H or higher 4: Pencil hardness F or higher 3: Pencil hardness HB or higher 2: Pencil hardness B or higher 1: Pencil hardness 2B or higher 0: Coating is 3B or less, or the coating is broken and measurement is not possible For practical purposes, a hardness rating of "3" or higher is desirable, with "4" or higher being even more desirable.

[0060] (7) Water and chemical resistance The polyurethane resin composition was applied to a metal plate using a Baker applicator to a thickness of 1 mm and cured at 25°C for 24 hours. The cured product was then peeled from the metal plate and cut into 20 mm x 20 mm x 1 mm test pieces, which were then immersed in distilled water, a 20% by weight aqueous sulfuric acid solution, a 10% by weight aqueous acetic acid solution, and a saturated aqueous calcium hydroxide solution at 60°C for 7 days. The test pieces were then evaluated according to the following criteria. In practical use, a chemical resistance rating of "3" or higher is desirable, with "4" or higher being even more desirable. 1: The absolute weight change before and after immersion is 10% or more 2: The absolute value of the weight change before and after immersion is 7.5% or more and less than 10% 3: The absolute value of the weight change before and after immersion is 5% or more and less than 7.5% 4: The absolute value of the weight change before and after immersion is 2.5% or more and less than 5% 5: The absolute weight change before and after immersion is less than 2.5%

[0061] Example 1 44.1 g of polyisocyanate compound (A'1) (0.525 mol of isocyanate group) and 55.9 g of polyamine compound (B'1) (0.525 mol of amino group) were mixed at 25°C using a metal stirring rod until a uniform appearance was achieved, thereby obtaining a polyurea resin composition (molar ratio (isocyanate group / amino group) = 1.0).

[0062] Examples 2 to 17, Comparative Examples 1 to 9 A polyurea resin composition was obtained in the same manner as in Example 1, except that the types of (A'), (A''), (B'), (B''), and (C) shown in Table 1 were used in the molar ratios shown in Table 1.

[0063] Table 1 shows the constitution of the polyurea resin compositions in the examples and comparative examples, and Table 2 shows the properties of the obtained polyurea resin compositions.

[0064] [Table 1]

[0065] [Table 2]

[0066] As shown in Tables 1 and 2, the polyurea resin compositions of the examples had good viscosity under solvent-free conditions, curing times suitable for casting applications, high hardness, and excellent chemical resistance and water resistance.

[0067] In Comparative Example 1, in which isophorone diisocyanate having a cyclic structure was used as the polyisocyanate compound, the curing time of the obtained polyurea resin composition was too long and it was not suitable for casting applications. In Comparative Examples 2 and 3, in which the polyisocyanate compound was an aromatic polyisocyanate compound, and Comparative Example 4, in which the content of the acyclic aliphatic polyisocyanate compound was low, the curing time of the obtained polyurea resin composition was too short and it was not suitable for casting applications. Comparative Example 5, which did not contain a polyamine compound, and Comparative Example 6, which did not contain a polyisocyanate compound, did not cure and were unsuitable. In Comparative Example 7, which did not contain polyamine compound (B'), and Comparative Example 8, which used polyol compound (C) instead of polyamine compound, the curing time was too long and they were unsuitable for casting applications, and they also had poor chemical resistance and water resistance. In Comparative Example 9, in which the polyisocyanate compound was a derivative of isophorone diisocyanate, the curing time was too long, making it unsuitable for casting applications, and it was poor in chemical resistance, water resistance, and hardness.

Claims

1. A polyurea resin composition containing a polyisocyanate compound (A) and a polyamine compound (B), wherein the polyisocyanate compound (A) contains 50 mass% or more of an acyclic isocyanate or a derivative thereof (A'), A polyurea resin composition, wherein the polyamine compound (B) contains a polyamine compound (B') having a cyclic structure containing no ester bond.

2. The polyurea resin composition according to claim 1, wherein the polyamine compound (B') satisfies the following (a) or (b): (a) Hexasubstituted benzene having two or more primary amino groups. (b) A compound represented by the following general formula (1): R １ -(NH)-R ２ -(NH)-R ３ (1) (R １ , R ３ are each independently an alkyl group, R ２ represents an organic group having a cyclic structure)

3. The polyurea resin composition according to claim 2, wherein the polyamine compound (B') satisfies the following condition (c) or (d): (c) Hexasubstituted benzene containing two or more primary amino groups and containing a halogen (d) A compound represented by the following general formula (2): R １ ´-(NH)-R ２ ´-(NH)-R ３ ´ (2) (R １ ´, R ３ ' are each independently an alkyl group having 2 to 14 carbon atoms, R ２ ' is an organic group having a cyclic structure and 6 to 20 carbon atoms)

4. The polyurea resin composition according to claim 1 or 2, wherein the proportion of the polyamine compound (B') in the polyamine compound (B) is 30 mass% or more.

5. The polyurea resin composition according to claim 1 or 2, wherein the polyamine compound (B') has a number average molecular weight of 100 to 5,000 and an amine value of 20 to 1200 mgKOH / g.

6. The polyurea resin composition according to claim 1 or 2, wherein the polyisocyanate compound (A) has an isocyanate group content of 5 to 50 NCO%.

7. 3. The polyurea resin composition according to claim 1, wherein the viscosity of the polyurea resin composition is 100 to 50,000 mPa s as measured with a Brookfield viscometer at 25°C immediately after mixing all of the components including the polyisocyanate compound (A) and the polyamine compound (B) under solvent-free conditions.

8. A coating film comprising the polyurea resin composition according to claim 1 or 2.

9. A cast-molded article comprising the polyurea resin composition according to claim 1 or 2.

10. A method for producing the polyurea resin composition according to claim 1 or 2, comprising: A production method comprising mixing a polyisocyanate compound (A) containing 50 mass% or more of an acyclic aliphatic isocyanate or a derivative thereof (A') with a polyamine compound (B) containing a polyamine compound (B') having a cyclic structure containing no ester bond.

11. A raw material for producing a two-component mixed polyurea resin composition containing a polyisocyanate compound (A) and a polyamine compound (B), The polyisocyanate compound (A) contains 50 mass% or more of an acyclic aliphatic isocyanate or a derivative thereof (A'), A raw material for producing a two-component mixed polyurea resin composition, wherein the polyamine compound (B) contains a polyamine compound (B') having a cyclic structure containing no ester bond.

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