Raw material for producing polyurea resin composition, polyurea resin composition, coating material, coating film, and coating method

Abstract

To provide a polyurea resin composition that exhibits high tensile strength combined with high breaking elongation, superior wear resistance, and an appropriate curing time for hand application.SOLUTION: A raw material for producing a polyurea resin composition comprises a polyisocyanate compound (A) and a polyamine compound (B), wherein the polyisocyanate compound (A) comprises a carbodiimide-modified aromatic isocyanate compound or a derivative thereof (A') and an aliphatic polyisocyanate compound or a derivative thereof (A''), and the polyamine compound (B) comprises a compound (B') represented by the following general formula (I): [(NH2)m-C6H5-m-COA-]nR (I). (In formula (I), R represents an n-valent polyalkylene, polyalkylene ether, or polyalkylene polyester having an average molecular weight of 80 or more; A represents an oxygen atom or an imino group. The polyalkylene may contain an unsaturated bond. m represents an integer of 1 to 3, and n represents an integer of 2 to 4.)SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a raw material for producing a polyurea resin composition, a polyurea resin composition, a paint, a coating film, and a coating method. [Background technology]

[0002] Two-component curing polyurea resin compositions, consisting of two components: polyisocyanates and a curing agent containing polyamines, cure at room temperature, and the resulting cured polyurea resin has excellent mechanical strength. Because spraying equipment cannot be used for coating in enclosed spaces or on complex shapes, polyurea resins with long working lives (curing times) that can be applied by hand (hereinafter referred to as hand coating) are being investigated.

[0003] Patent Document 1 reports a polyurea resin composition that uses an aliphatic polyisocyanate compound and an amine of a specific structure, resulting in a good curing time and excellent water and chemical resistance. Patent Document 2 reports a technology related to an adhesive that exhibits high tensile strength and elongation at break, making it suitable for structural bonding. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2023 / 238855 [Patent Document 2] Patent No. 7377744 Summary of the Invention [Problem to be solved by the invention]

[0005] In particular, coatings and protective / repair materials for items exposed to outdoor environments, such as buildings and wind power generation components, require not only high mechanical strength but also resistance to external environments (resistance to ultraviolet rays, acid rain, and maintaining performance despite temperature changes).

[0006] The polyurea resin composition disclosed in Patent Document 1 has room for further improvement in tensile strength and elongation at break in order to be used as a protective coating (coating film) for buildings and the like.

[0007] The urethane composition disclosed in Patent Document 2 does not include any description regarding resistance to external environments, and there is room for further improvement.

[0008] 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, when formed into a coating film, has both high tensile strength and high elongation at break, is excellent in resistance to external environments, and has a good curing time. [Means for solving the problem]

[0009] As a result of extensive research, the present inventors have found that the combined use of a carbodiimide-modified aromatic polyisocyanate and an aliphatic isocyanate improves external environmental resistance while maintaining high tensile strength and elongation at break, thereby providing a coating film that can solve the above-mentioned problems, and have completed the present invention. That is, the gist of the present invention is as follows.

[0010] (1) A raw material for producing a polyurea resin composition, comprising a polyisocyanate compound (A) and a polyamine compound (B), wherein the polyisocyanate compound (A) comprises a carbodiimide-modified aromatic polyisocyanate compound or a derivative thereof (A') and an aliphatic polyisocyanate compound or a derivative thereof (A''), and the polyamine compound (B) comprises a polyamine compound (B') represented by the following general formula (I): [(NH2) m -C6H 5-m -COA-] n R (I) (In formula (I), R represents an n-valent polyalkylene, polyalkylene ether, or polyalkylene polyester having an average molecular weight of 80 or more, A represents an oxygen atom or an imino group, provided that the polyalkylene may contain an unsaturated bond, m represents an integer of 1 to 3, and n represents an integer of 2 to 4.) (2) A raw material for producing a polyurea resin composition according to (1), wherein the polyisocyanate compound (A) contains 30 mass % or more of a carbodiimide-modified aromatic polyisocyanate compound (A'). (3) A raw material for producing a polyurea resin composition according to (1) or (2), wherein the carbodiimide-modified aromatic polyisocyanate compound (A') is a carbodiimide-modified product of diphenylmethane diisocyanate. (4) A raw material for producing a polyurea resin composition according to any one of (1) to (3), wherein the polyisocyanate compound (A) has an isocyanate group content of 15 to 30 NCO%. (5) A raw material for producing a polyurea resin composition according to any one of (1) to (4), wherein the content of the polyamine compound (B') per 100 parts by mass of the polyamine compound (B) is 30 parts by mass or more. (6) The raw material for producing a polyurea resin composition according to any one of (1) to (5), wherein the content of an amine compound other than the polyamine compound (B') is 50 parts by mass or less relative to 100 parts by mass of the polyamine compound (B). (7) A raw material for producing a polyurea resin composition according to any one of (1) to (6), in which the time required for the material to be dry to the touch after mixing all components including the polyisocyanate compound (A) and the polyamine compound (B) under solvent-free conditions is 15 minutes or more. (8) A polyurea resin composition obtained from the raw material for producing a polyurea resin composition according to any one of (1) to (7). (9) A paint containing the polyurea resin composition of (8). (10) A coating film obtained from the paint of (9). (11) A coating film according to (10), which has a tensile strength of 15 MPa or more and a breaking elongation of 150% or more, measured at a tensile speed of 200 mm / min using a 1 mm thick test piece in accordance with JIS K7161-1:2014, and which has an abrasion loss of 10 mg or less after 1000 revolutions in a Taber abrasion test measured under a load of 1000 g using a CS17 abrasive wheel in accordance with JIS 7204:1999. (12) Articles containing a coating film according to (10) or (11). (13) A coating method for applying the coating material of (9), wherein the coating material is applied by brush coating, roller coating, or trowel coating. [Effects of the Invention]

[0011] According to the raw material for producing a polyurethane resin composition of the present invention, it is possible to provide a polyurethane resin composition that has a good curing time suitable for use in hand application, and that also has high tensile strength and elongation at break, and that when formed into a coating film has excellent resistance to external environments, and a coating material made from the polyurethane resin composition. In addition, the polyurea resin composition of the present invention has excellent abrasion resistance and can therefore be suitably used, for example, as a coating material for components that are subject to high-speed collisions with fine components, such as rotating blades in wind power generation and the like. DETAILED DESCRIPTION OF THE INVENTION

[0012] <Raw materials for producing polyurea resin compositions> The raw material for producing the polyurea resin composition of the present invention contains a polyisocyanate compound (A) and a polyamine compound (B).

[0013] <Polyisocyanate compound (A)> The polyisocyanate compound (A) 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. Examples of the derivative of the isocyanate compound in the present invention include an isocyanate-terminated prepolymer obtained by reacting an isocyanate compound with a polyamine or a polyol, an allophanate-modified product, a urea-modified product, a carbodiimide-modified product, a biuret-modified product, a uretdione-modified product, an isocyanurate-modified product, and a water-dispersible modified product.

[0014] The polyisocyanate compound (A) in the present invention must contain a carbodiimide-modified aromatic polyisocyanate compound or a derivative thereof (A'). The content of the carbodiimide-modified aromatic polyisocyanate compound or a derivative thereof (A') can be adjusted as desired depending on the desired physical properties, but it is more preferably 30% by mass or more, even more preferably 50% by mass or more, and particularly preferably 60% by mass or more, based on the polyisocyanate compound (A). When the polyisocyanate compound (A) contains a carbodiimide-modified aromatic polyisocyanate compound or a derivative thereof (A'), the resulting polyurea resin composition has a tack-free time (curing time) suitable for hand application, and further, when formed into a coating film, it can achieve both high tensile strength and elongation at break, as well as high resistance to acid rain and temperature change.

[0015] The isocyanate group content of the carbodiimide-modified aromatic polyisocyanate compound or its derivative (A') is preferably 15 to 40 NCO% (mass%), more preferably 17 to 38 NCO% (mass%), and particularly preferably 20 to 35 NCO% (mass%). If the isocyanate group content exceeds 40 NCO%, the elongation at break of the resulting coating film may deteriorate, while if the isocyanate group content is less than 15 NCO%, the tensile strength of the resulting coating film may decrease.

[0016] Known carbodiimide-modified aromatic polyisocyanate compounds can be used, and examples thereof include carbodiimide-modified compounds such as 2,4-toluene diisocyanate (TDI), 2,6-toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, 1,5-naphthalene diisocyanate, and 1,4-phenylene diisocyanate.

[0017] Among these, a carbodiimide-modified product of diphenylmethane diisocyanate (MDI) is preferred. By using a carbodiimide-modified product of diphenylmethane diisocyanate as the carbodiimide-modified aromatic polyisocyanate compound (A'), it is possible to achieve even higher tensile strength and higher elongation at break.

[0018] The polyisocyanate compound (A) in the present invention must contain an aliphatic polyisocyanate or a derivative thereof (A"). When the polyisocyanate compound (A) contains an aliphatic polyisocyanate or a derivative thereof (A"'), the ultraviolet resistance and temperature change resistance of the coating film formed therefrom are improved, and a better tack-free time (curing time) can be achieved.

[0019] The content of the aliphatic polyisocyanate or its derivative (A") can be adjusted as desired depending on the desired physical properties, but is preferably 1 to 70 mass % relative to the polyisocyanate compound (A), more preferably 3 to 50 mass %, and particularly preferably 5 to 40 mass %. If the content is less than 1%, the effect of adding the aliphatic polyisocyanate or its derivative (A") may not be fully exerted, and if the content exceeds 70 mass %, the tensile strength and elongation at break may decrease.

[0020] Examples of aliphatic polyisocyanate compounds 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 methyl caproate, lysine diisocyanate, trioxyethylene diisocyanate, isophorone diisocyanate, Examples of suitable isocyanates include methyl isocyanate, 1,4-bis(isocyanatomethyl)cyclohexane, 4,4'-methylenebis(cyclohexyl isocyanate), 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, and 2,5- or 2,6-bis(isocyanatomethyl)norbornane (NBDI).

[0021] Among these, 1,5-pentamethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and 4,4'-methylenebis(cyclohexylisocyanate) are preferred, with 1,5-pentamethylene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate being more preferred, and hexamethylene diisocyanate being particularly preferred. When the polyisocyanate compound (A) contains these aliphatic isocyanates or their derivatives, the resulting coating film has improved properties such as resistance to external environments. Furthermore, aliphatic isocyanate derivatives can be obtained by known methods.

[0022] The isocyanate group content of the aliphatic polyisocyanate or its derivative (A") is preferably 15 to 30 NCO% (mass%), more preferably 7 to 28 NCO% (mass%), and particularly preferably 10 to 25 NCO% (mass%). If the isocyanate group content exceeds 30 NCO%, the elongation at break of the resulting coating film may deteriorate, while if the isocyanate group content is less than 5 NCO%, the tensile strength of the resulting coating film may decrease or the ultraviolet resistance may deteriorate.

[0023] The polyisocyanate compound (A) may contain, in addition to the carbodiimide-modified aromatic polyisocyanate compound (A') and the aliphatic polyisocyanate compound and its derivative (A"), other polyisocyanate compounds (A'") depending on the desired performance such as physical properties and curing time. Examples of other polyisocyanate compounds (A'") include 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, and 1,5-naphthylene diisocyanate.

[0024] The content of the other polyisocyanate compound (A'") is not particularly limited and can be added according to the desired performance, but is preferably 30% by mass or less, more preferably 25% by mass or less, and particularly preferably 20% by mass or less, relative to the polyisocyanate compound (A). If it exceeds 30% by mass, the resulting coating film may be inferior in elongation at break and abrasion resistance.

[0025] The isocyanate group content in the polyisocyanate compound (A) is preferably 15 to 30 NCO% (mass%), more preferably 18 to 30 NCO% (mass%), even more preferably 20 to 30 NCO% (mass%), and particularly preferably 22 to 30 NCO% (mass%). A polyurea resin composition containing a polyisocyanate compound (A) with an isocyanate group content higher than the above range may not achieve a good tack-free time, and if the isocyanate group content in the polyisocyanate compound (A) is lower than the above range, the resulting coating film may have poor tensile strength.

[0026] <Polyamine compound (B)> The polyamine compound (B) in the present invention contains a polyamine compound (B') (hereinafter sometimes referred to as a benzoate-based polyamine compound (B')) represented by the following general formula (I): [(NH2) m -C6H 5-m -COA-] n R (I) (In formula (I), R represents an n-valent polyalkylene, polyalkylene ether, or polyalkylene polyester having an average molecular weight of 80 or more, A represents an oxygen atom or an imino group, provided that the polyalkylene may contain an unsaturated bond, m represents an integer of 1 to 3, and n represents an integer of 2 to 4.)

[0027] By including polyamine compound (B') in polyamine compound (B), the polyamine compound (B) has a tack-free time (curing time) suitable for hand application, and furthermore, when formed into a coating film, it is possible to achieve high tensile strength, elongation at break, resistance to external environments, and abrasion resistance.

[0028] The content of polyamine compound (B') is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 60% by mass or more, based on the total amount of polyamine compound (B). If it is less than 30% by mass, the resulting coating film may be inferior in breaking elongation and abrasion resistance, or a satisfactory curing time may not be achieved.

[0029] Among the above benzoate-based polyamine compounds (B'), examples of commercially available products in which m = 1, n = 2, and R is a polyether include "Elasmer 1000P" (manufactured by Kumiai Chemical Industry Co., Ltd., amine value 84 g KOH / g), "Elasmer 650P" (manufactured by Kumiai Chemical Industry Co., Ltd., amine value 126 g KOH / g), "Elasmer 250P" (manufactured by Kumiai Chemical Industry Co., Ltd., amine value 221 g KOH / g), "VERSALINK P-1000" (manufactured by Air Products Japan Co., Ltd., amine value 80 to 90), and "Porea SL-100A" (manufactured by Kumiai Chemical Industry Co., Ltd.).

[0030] The polyamine compound (B) of the present invention may contain a polyamine compound (B'') other than the benzoate-based polyamine compound (B') for the purpose of adjusting the coating film properties and curing time. Examples of the other amine compound (B") include aromatic amine compounds such as 4,4'-diamino-3,3'-dichlorodiphenylmethane, 4,4'-methylenebis(N-sec-butylaniline), N,N'-di-sec-butyl-p-phenylenediamine, and diethyltoluenediamine; polyether amine compounds such as O,O'-bis(2-aminopropyl)propylene glycol; and aliphatic amine compounds such as hexamethylenediamine, nonanediamine, 4,4'-methylenebis(N-sec-butylcyclohexanamine), and reaction products of epoxy compounds and primary amines. The other amine compound (B") can be either a primary amine or a secondary amine.

[0031] The content of the other amine compound (B") is preferably 0 to 50 parts by mass, more preferably 0 to 40 parts by mass, and particularly preferably 0 to 30 parts by mass, relative to 100 parts by mass of the total of the other amine compound (B") and the benzoate-based polyamine compound (B). If the content of the other amine compound (B") exceeds 50 parts by mass, the polyurea resin composition may have poor elongation at break.

[0032] <Other ingredients (C)> The raw materials for producing the polyurea resin composition of the present invention may contain a compound or resin having a functional group other than an amino group that reacts with an isocyanate group, as long as the effects of the invention are not impaired. The type of liquid resin is not particularly limited, but examples include polyol compounds, epoxy compounds, polyester compounds, polyolefin compounds, polyamide compounds, polycarboxylic acid compounds, methacrylic compounds, vinyl ester compounds, polyurethane compounds, and resins thereof. Among these, polyol resins are preferred in order to achieve high elongation at break.

[0033] The molecular weight of the other component (C) is not particularly limited, and any of a monomer, oligomer, and polymer can be used.

[0034] The content of the other component (C) in the raw material for producing the polyurea resin composition of the present invention is preferably 20% by mass or less, more preferably 10% by mass or less, and particularly preferably 5% by mass or less, based on the total of the polyisocyanate compound (A), the polyamine compound (B), and the other component (C). If the content of the other component (C) exceeds 20% by mass, the polyurea resin composition may have poor tensile strength.

[0035] In the raw materials for producing the polyurea resin composition of the present invention, the equivalent ratio (NCO / NH2) of the isocyanate groups of the polyisocyanate compound (A) to the amino groups of the polyamine compound (B) is preferably 0.6 to 1.5, more preferably 0.8 to 1.2, even more preferably 0.9 to 1.1, and particularly preferably 0.95 to 1.05. Furthermore, when other component (C) is contained, the total amount of amino groups of the polyamine compound (B) and the active hydrogen groups of other component (C) is used instead of the amount of amino groups of the polyamine compound (B). If the equivalent ratio is less than 0.6 or more than 1.5, a cured product such as a coating film may not be obtained, or the coating film may have poor physical properties such as tensile strength.

[0036] The raw materials for producing the polyurea resin composition of the present invention may contain a catalyst in order to improve the physical properties of the resulting coating film or to adjust the curing time or temperature. Specific examples of the catalyst include tertiary amines such as triethylamine, tributylamine, triethylenediamine, 2-dimethylaminoethyl ether, diazabicycloundecene, and N-methylmorpholine; metal-based catalysts such as dibutyltin diacetate, dibutyltin laurate, 3-diacetoxytetrabutylstannoxane, tin octenoate, tin chloride, tin butyl trichloride, bismuth trichloride, bismuth octenoate, tetrakis(2-ethylhexyl)titanate, tetrabutoxytitanium, and metal salts of acetoacetic acid; quaternary ammonium salts such as tetramethylammonium chloride; and acidic compounds such as hydrochloric acid, sulfuric acid, acetic acid, succinic acid, and trifluoromethanesulfonic acid.

[0037] The raw materials for producing the polyurea resin composition of the present invention may contain additives as needed. Examples of additives include basic inorganic compounds, pH adjusters, metal oxide fine particles, tackifiers, waxes, UV absorbers, surface conditioners, antifoaming agents, thixotropy-imparting agents, colorants, dispersants, fillers, and diluents. These may be used alone or in combination of two or more. They may also be mixed in advance with the polyisocyanate compound (A) and the polyamine compound (B). The amount of the additive to be added can be determined appropriately depending on the purpose.

[0038] Examples of basic inorganic compounds include hydroxides, oxides, and (hydrogen)carbonates of alkali metals or alkaline earth metals, such as calcium hydroxide, sodium hydroxide, magnesium hydroxide, calcium oxide, calcium carbonate, sodium carbonate, and sodium hydrogencarbonate. Among these, hydroxides of alkali metals or alkaline earth metals are more preferred from the viewpoint of their influence on stability and viscosity.

[0039] Examples of pH adjusters include organic acid salts of alkali metals or alkaline earth metals, such as calcium acetate, sodium acetate, potassium acetate, calcium formate, sodium formate, potassium formate, calcium propionate, sodium propionate, and potassium propionate.

[0040] Examples of metal oxide fine particles include titanium oxide, magnesium oxide, ferrous oxide, ferric oxide, triiron tetroxide, aluminum oxide, vanadium oxide, and copper oxide.

[0041] Examples of tackifiers include polysaccharides such as xanthan gum and guar gum, rosin resins and derivatives thereof, terpene resins and derivatives thereof, aliphatic resins and derivatives thereof, and aromatic resins and derivatives thereof.

[0042] Examples of waxes include paraffin wax, amide wax, olefin wax, olefin oxide wax, montan wax, and copolymer wax.

[0043] Examples of ultraviolet absorbers include hindered amine-based, cinnamic acid-based, benzophenone-based, triazine-based, and triazole-based ones.

[0044] Examples of the surface conditioner include silicone-based, acrylic polymer-based, vinyl-based, acetylene-based, fluorine-based, and alkylene oxide-based agents.

[0045] Examples of antifoaming agents include mineral oil-based, amide-based, metal soap-based, silicone-based, higher alcohols and derivatives thereof, fatty acid derivatives, polyolefin-based, etc. Among these, polyolefin-based agents are more preferred from the viewpoints of antifoaming properties and chemical resistance.

[0046] Examples of the thixotropy-imparting agent include acrylic polymers, organic urea compounds and modified compounds thereof, fumed silica, bentonite, organic clay, layered silicates, etc. Among these, from the viewpoint of the effect relative to the amount added, organic urea compounds and modified compounds thereof are more preferred.

[0047] Any of inorganic pigments, organic pigments, and dyes can be used as colorants. Examples of inorganic pigments include red clay, yellow clay, green clay, graphite, Prussian blue, zinc oxide, cobalt blue, viridian, and titanium white. Examples of organic pigments include alkali blue, lysol red, disazo yellow, phthalocyanine blue, quinacridone red, and isoindoline yellow. Examples of dyes include madder, sappan, and indigo.

[0048] Examples of dispersants include acrylic polymers, polycarboxylic acid compounds, phosphonic acid compounds, sulfonic acid compounds and neutralized compounds thereof, quaternary ammonium salt compounds, amide compounds, and polyether compounds.

[0049] Examples of fillers include inorganic compounds such as calcium carbonate and calcium hydroxide, inorganic minerals such as talc, kaolin, apatite and layered silicates, glass beads, glass fiber, silica, etc. Among these, talc, glass beads and silica are preferred from the viewpoints of the amount added and viscosity.

[0050] As the diluent, any common organic solvent can be used 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.

[0051] The content of the organic solvent in the raw materials for producing the polyurea resin composition is preferably 10% by mass or less. If the content of the organic solvent 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 is, the ability to be produced without a solvent, may be lost.

[0052] The raw material for producing the polyurea resin composition of the present invention is prepared by mixing all components, including the polyisocyanate compound (A) and the polyamine compound (B), under solvent-free conditions, and immediately after mixing (for example, after 30 seconds), the viscosity at 25°C is preferably 100 to 500,000 mPa·s, more preferably 500 to 300,000 mPa·s, and particularly preferably 1,000 to 200,000 mPa·s. If the viscosity is less than 100 mPa·s, it may be difficult to obtain a coating film with sufficient thickness, while if it exceeds 500,000 mPa·s, it may be difficult to remove air bubbles from the resulting resin composition, making the coating process difficult.

[0053] The raw material for producing the polyurea resin composition of the present invention is preferably tack-dry in 15 minutes or more, more preferably 30 minutes or more, even more preferably 45 minutes or more, and particularly preferably 60 minutes or more after mixing all components including the polyisocyanate compound (A) and the polyamine compound (B) under solvent-free conditions. If the tack-dry time is less than 15 minutes, the coating workability may be poor.

[0054] The polyurea resin composition of the present invention is obtained from the raw materials for producing the polyurea resin composition of the present invention. The method for obtaining the polyurea resin composition of the present invention is not particularly limited, and any mixing method can be used, as long as it involves mixing all components including the polyisocyanate compound (A) and the polyamine compound (B). Furthermore, the mixing conditions (mixing temperature and mixing time) are not particularly limited, and can be appropriately selected depending on the physical properties of the resulting resin composition.

[0055] The coating material of the present invention contains the polyurea resin composition of the present invention. The coating film of the present invention is formed by applying the coating material of the present invention.

[0056] Because the raw materials for producing the polyurea resin composition of the present invention have a sufficient dry-to-touch time, known methods can be used to apply the coating. The coating method can be selected appropriately depending on the desired thickness and the shape of the substrate, but examples include immersion coating (dipping, dipping coating), wire bar coating, Baker-type applicator coating, gravure roll coating, potting, brush coating, roller coating, and trowel coating. It is also possible to form a three-dimensional cured product using a 3D printer or the like.

[0057] The thickness of the coating film can be selected appropriately depending on the desired physical properties, the material of the article or substrate to be coated, etc., but from the standpoint of economy and physical properties, it is usually preferably 10 to 10,000 μm, more preferably 50 to 8,000 μm, and even more preferably 100 to 5,000 μm. The thickness can be obtained by applying the coating in one go or by applying the coating in multiple steps.

[0058] The coating film of the present invention has good tensile strength, elongation at break, abrasion resistance, and resistance to external environments, and can therefore be suitably used as a layer for protecting substrates or preventing the penetration of specific substances. Specific examples include coated floors, linings, roof waterproofing, exterior wall coatings, bridge deck waterproofing, waterproof paints, anticorrosion paints, protective paints for steel pipes, metal pipes, tank interiors and exteriors, and wind power generation components, reinforcement and repair of buildings, protection of plastic and metal parts, and reservoirs. In particular, because of its excellent abrasion resistance, it can be suitably used as a paint for substrates or articles that are subject to high-speed collisions with fine particles, such as rotating blades in wind power generation systems.

[0059] The coating film of the present invention can also be combined with flat bodies such as fibers (including both long and short fibers), nonwoven fabrics (including both long and short fibers), cloth, wire netting, mesh, and punched metal. Any known method can be used for the composite formation. The amount of coating when compounding with the flat body can be appropriately selected depending on the desired physical properties and the material of the substrate, but is usually 0.01 to 5 kg / m from the viewpoints of economy and physical properties. 2is preferable, and 0.03 to 4 kg / m 2 More preferably, 0.05 to 3 kg / m 2 is more preferable.

[0060] The coating film of the present invention preferably has a tensile strength of 15 MPa or more, more preferably 20 MPa or more, and even more preferably 25 MPa or more, as measured in accordance with JIS K7161-1:2014 using a 1 mm thick test piece at a pulling rate of 200 mm / min. The elongation at break is also preferably 150% or more, more preferably 200% or more, even more preferably 250% or more, and particularly preferably 300% or more. If the tensile strength is less than 20 MPa or the elongation at break is less than 150%, the coating film may not be able to protect the substrate or article to be protected.

[0061] The coating film of the present invention preferably exhibits an abrasion loss of 10 mg or less, more preferably 7.5 mg or less, and even more preferably 5 mg or less after 1000 revolutions in a Taber abrasion test measured under a load of 1000 g using a CS17 abrasive wheel according to JIS 7204: 1999. If the abrasion loss is 10 mg or more, the ability to protect the substrate or article to be protected may be poor. [Example]

[0062] 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. The raw materials used in the examples and comparative examples are listed below. The raw materials were used as they were without purification or distillation.

[0063] <Polyisocyanate compound (A)> <Carbodiimide-modified aromatic polyisocyanate (A')> A´1: Carbodiimide-modified MDI (Tosoh Corporation's "Millionate MTL", 28.9 NCO%, viscosity 42 mPa·s) A´2: Carbodiimide-modified TDI synthesized by the following method, 28.0 NCO%, viscosity 30 mPa·s A four-neck flask equipped with a stirrer, a thermometer, a condenser, and a nitrogen gas inlet tube was charged with 3,000 parts by mass of TDI (2,4-tolylene diisocyanate / 2,6-tolylene diisocyanate = 80 / 20 (weight ratio)) and 0.012 parts by mass of 1-phenyl-3-methyl-3-phospholene-1-oxide, and the temperature was raised to 90°C while stirring to form a carbodiimide. When the isocyanate group content reached 28 NCO%, 0.36 parts by mass of β-naphthalenesulfonic acid was added, and the reactor was rapidly cooled to 45° C. with ice water to terminate the carbodiimidization reaction.

[0064] <Aliphatic polyisocyanate compound (A´´)> A´´1: Nurate-modified hexamethylene diisocyanate (Tosoh Corporation's "Coronate HXR", 21.9 NCO%, viscosity 3,000 mPa·s) A´´2: 1,6-hexamethylene diisocyanate (Tokyo Chemical Industry Co., Ltd., 49.9 NCO%, viscosity 3 mPa·s) A´´3: Water-dispersible modified hexamethylene diisocyanate (Asahi Chemical Industry Co., Ltd. "Duranate WL72-100", 21.3 NCO%, viscosity 540 mPa s)

[0065] A´´4: 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, and a urethane reaction was carried out. 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.

[0066] A´´5: Biuret-modified hexamethylene diisocyanate (Asahi Chemical Industry Co., Ltd. "Duranate 24A-100", 23.5 NCO%, viscosity 1,800 mPa s)

[0067] <Other polyisocyanate compounds (A´´´)> A´´´´1: Polymeric MDI (Tosoh Corporation's "Millionate MR-200", 30.9 NCO%, viscosity 150 mPa·s)

[0068] <Polyamine compound (B)> <Benzoate-based polyamine compound (B')> B´1: Polytetramethylene oxide-di-p-aminobenzoate (Kumiai Chemical Co., Ltd. "Elasmer 1000P", amine value 84 mg KOH / g, molecular weight 1238, viscosity 5,300 mPa·s) B´2: Polytetramethylene oxide-di-p-aminobenzoate (Kumiai Chemical Co., Ltd. "Elasmer 650P", amine value 126 mg KOH / g, molecular weight 888, viscosity 6,000 mPa·s) B´3: Polytetramethylene oxide-di-p-aminobenzoate (Kumiai Chemical Co., Ltd. "Elasmer 250P", amine value 221 mg KOH / g, molecular weight 488, viscosity 175,000 mPa·s)

[0069] <Other polyamine compounds (B´´)> B´´1: 4.4´-methylenebis(N-sec-butylaniline) (Dorfketal "Unilink 4200", amine value 362 mg KOH / g, viscosity 324 mPa s)

[0070] <Other ingredients (C)> C1: Glycerin-propylene oxide adduct (ADEKA "G-700", hydroxyl value 224 mg KOH / g, viscosity 250 mPa·s)

[0071] Various physical properties were measured by the following evaluation methods. (1) Isocyanate group content (NCO%) It was determined according to the hydrochloric acid back titration method for di-n-butylamine specified in JIS K 7301.

[0072] (2) Amine value It was determined according to the indicator titration method of JIS K 7237.

[0073] (3) NCO / NH2 equivalent ratio It was calculated from the isocyanate group content and amine value obtained in (1) and (2) above.

[0074] (4) Viscosity All components including the polyisocyanate compound (A) and the polyamine compound (B) were mixed together, and the rotational viscosity (mPa·s) at 25°C was measured after 30 seconds using a Brookfield Dial Viscometer (BROOKFIELD ENGINEERING LABORATORIES, INC., BROOKFIELD DIAL VISCOMETER Model LVT).

[0075] (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 stirring rod 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 defined as the time it took for no transfer of the resin component to the film when a polyethylene film was lightly pressed against the resin composition, and was evaluated according to the following criteria. 5: Dry to the touch in over 2 hours and up to 4 hours 4: Dry to the touch time is more than 90 minutes but less than 2 hours, or more than 4 hours but less than 6 hours 3: Dry to the touch time is more than 60 minutes but less than 90 minutes, or more than 6 hours but less than 12 hours 2: Dry to the touch time is more than 30 minutes but not more than 60 minutes, or more than 12 hours but not more than 24 hours 1: Dry to the touch time is more than 5 minutes but less than 30 minutes, or more than 24 hours but less than 36 hours 0: Dry to the touch in 5 minutes or less or over 36 hours In practice, a rating of "2" or higher is preferable for the dry-to-touch time, and a rating of "3" or higher is even more preferable.

[0076] (6) Tensile strength and elongation at break All components, including the polyisocyanate compound (A) and the polyamine compound (B), were placed in a glass container (100 mL) and rapidly mixed at 25°C using a metal stirrer until uniform. The mixture was then poured into a 30 cm x 30 cm metal frame and cured at 40°C for 48 hours to obtain a 1 mm thick cured product. This was then punched out into dumbbell-shaped tensile test specimens (Type A1) as specified in JIS K7139. Tensile strength and elongation at break were measured using a Shimadzu thermostatic chamber tensile tester at 23°C, a test speed of 200 mm / min, and a chuck distance of 70 mm. Evaluation was based on the following criteria. (tensile strength) 5:25MPa or more 4: 20 MPa or more, less than 25 MPa 3: 15 MPa or more, less than 20 MPa 2: 10 MPa or more, less than 15 MPa 1: Less than 10MPa (Elongation at break) 5:250% or more 4: 200% or more, less than 250% 3: 150% or more, less than 200% 2: 100% or more, less than 150% 1: Less than 100% In practice, the tensile strength and elongation at break are preferably rated "2" or higher, and more preferably "3" or higher.

[0077] (7) Abrasion resistance All components, including the polyisocyanate compound (A) and the polyamine compound (B), were placed in a glass container (100 mL capacity) and rapidly mixed at 25°C using a metal stirrer until uniform. The mixture was then poured into a 30 cm x 30 cm metal frame and cured at 40°C for 48 hours to obtain a 1 mm thick cured product. This was then cut into a 10 cm x 10 cm test piece (test piece mass: 10 g). This test piece was subjected to a Taber abrasion test in accordance with JIS 72040:1999 using a Toyo Seiki Co., Ltd. Taber abrasion tester. A CS17 abrasion wheel was used, with a load of 1000 g and 1000 revolutions per minute. The mass was measured before and after the test, and the difference in mass before and after the test was taken as the abrasion loss. Evaluation was made according to the following criteria. 5: Wear loss of 2.5 mg or less 4: Wear loss is greater than 2.5 mg and less than 5.0 mg 3: Wear loss is greater than 5.0 mg and less than 7.5 mg 2: Wear loss is greater than 7.5 mg and less than 10.0 mg 1: Wear loss is greater than 10.0 mg and less than 12.5 mg 0: Wear loss exceeds 12.5 mg In practice, a rating of "2" or higher is preferable for abrasion resistance, and a rating of "3" or higher is even more preferable.

[0078] (8) Acid rain resistance All components, including the polyisocyanate compound (A) and the polyamine compound (B), were placed in a glass container (100 mL) and rapidly mixed at 25°C using a metal stirrer until uniform. The mixture was then poured into a 30 cm x 30 cm metal frame and cured at 40°C for 48 hours to obtain a 1 mm-thick cured product. This was then punched out to obtain dumbbell-shaped tensile test specimens (Type A1) as specified in JIS K7139. These specimens were immersed in a 5% aqueous sulfuric acid solution at 60°C for 120 days. After immersion, the specimens were rinsed with water and dried at 25°C for 24 hours. The tensile strength and elongation at break were measured under the same conditions as in (6). The test score was 10, and the average was used. Acid rain resistance was evaluated based on the results using the following criteria. 5: The larger of the absolute values ​​of the rate of change in tensile strength and elongation at break is 1% or less 4: The larger of the absolute values ​​of the rate of change of tensile strength and elongation at break is more than 1% and less than 5% 3: The larger of the absolute values ​​of the rate of change of tensile strength and elongation at break is more than 5% and less than 15% 2: The larger of the absolute values ​​of the rate of change in tensile strength and elongation at break is greater than 15% and less than 30% 1: The larger of the absolute values ​​of the rate of change in tensile strength and elongation at break is greater than 30% and less than 50% 0: The larger of the absolute values ​​of the rate of change in tensile strength and breaking elongation exceeded 50%, or the test piece was dissolved. In practice, a rating of "2" or higher is preferable, and a rating of "3" or higher is even more preferable.

[0079] (9) UV resistance All components, including the polyisocyanate compound (A) and the polyamine compound (B), were placed in a glass container (100 mL capacity) and quickly mixed at 25°C using a metal stirrer until uniform. The mixture was then poured into a 30 cm x 30 cm metal frame and cured at 40°C for 48 hours to obtain a 1 mm thick cured product. This was cut into a 75 mm x 150 mm piece and subjected to accelerated weathering tests according to JIS K 5600-7-8 using a Q-Lab Corporation QUV accelerated weathering tester. A UVA (340) lamp was used, with an illuminance of 0.89 W / m. 2 The black panel temperature was maintained at 60°C (irradiation) for 4 hours and then at 50°C (water spray) for 4 hours, and this cycle was repeated 125 times. The test pieces were washed with water and dried for 24 hours at 25° C. Thereafter, the tensile strength and elongation at break were measured, and the rate of change before and after the test was determined and evaluated according to the following criteria. 5: The larger of the absolute values ​​of the rate of change in tensile strength and elongation at break is 10% or less 4: The larger of the absolute values ​​of the rate of change in tensile strength and elongation at break is more than 10% and less than 20% 3: The larger of the absolute values ​​of the rate of change in tensile strength and elongation at break is more than 20% and less than 30% 2: The absolute value of the rate of change between tensile strength and elongation at break, whichever is larger, is greater than 30% and less than 50% 1: The larger of the absolute values ​​of the rate of change of tensile strength and elongation at break is more than 50% and less than 100% 0: The larger of the absolute values ​​of the rate of change in tensile strength and elongation at break exceeded 100%, or the test piece was cracked and could not be evaluated. In practice, a rating of "2" or higher is necessary, and a rating of "3" or higher is more preferable.

[0080] (10) Temperature change resistance The tensile strength and elongation at break were measured in the same manner as in (6) except that the measurement temperatures were set to -10°C and 40°C. Thereafter, the samples were evaluated according to the following criteria. 5: With 25°C as the base temperature, the larger of the absolute values ​​of the rate of change in tensile strength and elongation at break at -10°C and 40°C is 20% or less 4: With 25°C as the base temperature, the absolute value of the rate of change in tensile strength and elongation at break at -10°C and 40°C, whichever is greater, is more than 20% and not more than 40%. 3: With 25°C as the base temperature, the absolute value of the rate of change in tensile strength and elongation at break at -10°C and 40°C, whichever is greater, is more than 40% and not more than 80% 2: With 25°C as the reference temperature, the absolute value of the rate of change in tensile strength and elongation at break at -10°C and 40°C, whichever is greater, is greater than 80% and less than 140% 1: With 25°C as the base temperature, the larger of the absolute values ​​of the rate of change in tensile strength and elongation at break at -10°C and 40°C is more than 140% and less than 200% The absolute value of the change rate of tensile strength and elongation at break at -10°C and 40°C, with 0:25°C as the reference temperature, exceeds 200%, or the test piece melts or cracks. In practice, a rating of "2" or higher is preferable, and a rating of "3" or higher is more preferable.

[0081] Example 1 14.8 g of polyisocyanate compound (A'1) (0.102 mol of isocyanate groups), 3.7 g of polyisocyanate compound (A''1) (0.019 mol of isocyanate groups), and 81.5 g of polyamine compound (B'1) (0.121 mol of amino groups) were mixed at 25°C using a metal stirring rod until a uniform mixture was obtained, yielding a polyurea resin composition (molar ratio (isocyanate groups / amino groups) = 1.0 / 1.0). The composition was then evaluated using the evaluation methods described above in (1) to (10).

[0082] Examples 2 to 15, Comparative Examples 1 to 8 A polyurea resin composition was obtained in the same manner as in Example 1, except that (A'), (A"), (A""), (B'), (B"), and (C) shown in Table 1 were used. Thereafter, evaluations were carried out using the evaluation methods described above in (1) to (10).

[0083] 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.

[0084] [Table 1]

[0085] [Table 2]

[0086] As shown in Tables 1 and 2, the polyurethane resin compositions of the present invention obtained in the examples had high tensile strength and breaking elongation when formed into coating films, had curing times suitable for hand application, and were also excellent in external environment resistance and abrasion resistance.

[0087] Comparative Examples 1 and 2, in which the polyisocyanate compound did not contain the aliphatic polyisocyanate (A''), had a fast curing time and were unsuitable for hand application. In addition, the coating film had poor ultraviolet resistance.

[0088] In Comparative Example 3, in which the polyisocyanate compound did not contain the carbodiimide-modified aromatic polyisocyanate compound (A'), the curing time was slow, and the coating film was poor in both tensile strength and elongation at break.Furthermore, the acid rain resistance and temperature change resistance were also poor.

[0089] In Comparative Example 4, in which the polyisocyanate compound did not contain the carbodiimide-modified aromatic polyisocyanate compound (A'), curing was extremely rapid, and it was not possible to prepare a test piece required for performance evaluation.

[0090] Comparative Example 5, in which the polyamine compound did not contain the polyamine compound (B'), not only exhibited a fast curing time but also exhibited poor tensile strength and elongation at break, as well as poor abrasion resistance.

[0091] In both Comparative Example 6, which did not contain a polyamine compound, and Comparative Example 7, which did not contain a polyisocyanate compound, curing did not progress and evaluation was not possible.

[0092] In Comparative Example 8, in which a polyol compound was used instead of a polyamine compound, the curing time was slow and the tensile strength was poor, and furthermore, the acid rain resistance and temperature change resistance were also poor.

Claims

1. A raw material for producing a polyurea resin composition, comprising a polyisocyanate compound (A) and a polyamine compound (B), The polyisocyanate compound (A) contains a carbodiimide-modified aromatic polyisocyanate compound or a derivative thereof (A') and an aliphatic polyisocyanate compound or a derivative thereof (A''); A raw material for producing a polyurea resin composition, wherein the polyamine compound (B) contains a polyamine compound (B') represented by the following general formula (I): [(NH ２ ) ｍ -C ６ H ５－ｍ -COA-] ｎ R (I) (In formula (I), R represents an n-valent polyalkylene, polyalkylene ether, or polyalkylene polyester having an average molecular weight of 80 or more, A represents an oxygen atom or an imino group, provided that the polyalkylene may contain an unsaturated bond, m represents an integer of 1 to 3, and n represents an integer of 2 to 4.)

2. 2. The raw material for producing a polyurea resin composition according to claim 1, wherein the polyisocyanate compound (A) contains 30 mass% or more of the carbodiimide-modified aromatic polyisocyanate compound (A').

3. 2. The raw material for producing a polyurea resin composition according to claim 1, wherein the carbodiimide-modified aromatic polyisocyanate compound (A') is a carbodiimide-modified product of diphenylmethane diisocyanate.

4. The raw material for producing a polyurea resin composition according to claim 1, wherein the polyisocyanate compound (A) has an isocyanate group content of 15 to 30 NCO%.

5. 2. The raw material for producing a polyurea resin composition according to claim 1, wherein the content of the polyamine compound (B') relative to 100 parts by mass of the polyamine compound (B) is 30 parts by mass or more.

6. The raw material for producing a polyurea resin composition according to claim 1, wherein the content of an amine compound other than the polyamine compound (B') is 50 parts by mass or less relative to 100 parts by mass of the polyamine compound (B).

7. 2. The raw material for producing a polyurea resin composition according to claim 1, wherein the time required for the mixture to be dry to the touch after mixing all of the components including the polyisocyanate compound (A) and the polyamine compound (B) under solvent-free conditions is 15 minutes or more.

8. A polyurea resin composition obtained from the raw material for producing a polyurea resin composition according to any one of claims 1 to 7.

9. A paint comprising the polyurea resin composition according to claim 8.

10. A coating film obtained from the coating material according to claim 9.

11. The coating film according to claim 10, which has a tensile strength of 15 MPa or more and an elongation at break of 150% or more, as measured in accordance with JIS K7161-1:2014 using a 1 mm thick test piece at a pulling rate of 200 mm / min, and which has an abrasion loss of 10 mg or less after 1000 revolutions in a Taber abrasion test measured in accordance with JIS 7204:1999 using a CS17 abrasion wheel under a load of 1000 g.

12. An article comprising the coating of claim 10 or 11.

13. 10. A coating method for applying the paint according to claim 9, wherein the method for applying the paint is brush coating, roller coating, or trowel coating.

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