Curable compositions, sealants and adhesives

Abstract

To provide a curable composition with a small color difference before and after curing, which reduces development of gloss after curing and exhibits an excellent anti-fouling effect over a long period of time.SOLUTION: A curable composition includes: a polymer (I) having a hydrolyzable silyl group, including a polyalkylene oxide (A) having a hydrolyzable silyl group; a monoamine compound (C); and a diamine compound including a diamine compound (D) having a melting point equal to or lower than the melting point of the monoamine compound (C).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a curable composition that cures in the presence of atmospheric moisture to give a cured product that can exhibit excellent antifouling properties over a long period of time, and to a sealant and adhesive that use the same. [Background technology]

[0002] Conventionally, a curable composition containing an oxyalkylene polymer having a crosslinkable hydrolyzable silyl group has been known (Patent Document 1). The curable composition produces a cured product with excellent adhesiveness by hydrolyzing the crosslinkable hydrolyzable silyl group due to moisture in the atmosphere and then dehydrating and condensing.

[0003] Such curable compositions are used, for example, in the exterior walls of building structures, by filling the joints (so-called "joints") between exterior wall members such as mortar boards, concrete boards, ALC (Autoclaved Lightweight Concrete) boards, metal boards, etc., to join the exterior wall members together. By using the curable composition in this way, rainwater is prevented from penetrating into the interior of the building structure through the joints between the exterior wall members.

[0004] In the exterior walls of building structures, the width of joints changes slightly as exterior wall components expand or contract with temperature changes, or as exterior wall components move due to vibrations or external forces caused by earthquakes or strong winds. Therefore, it is necessary for the curable composition to have excellent rubber elasticity after curing and be able to expand and contract so as to follow changes in the width of the joints.

[0005] In recent years, the surfaces of exterior wall components constituting the exterior walls of building structures have sometimes been treated with antifouling treatments. In such cases, the exterior wall components are less susceptible to dirt, allowing the exterior wall to maintain its beautiful appearance for a long period of time. However, the cured product of the curable composition filled in the joints has not been treated with antifouling treatment. In addition, the cured product of the curable composition is designed to have high flexibility so that it can adapt to changes in the width of the joints. In such cases, tack remains on the surface of the cured product of the curable composition, which allows dirt to adhere to the surface of the cured product of the curable composition due to dust and contaminants. This has led to the problem of impaired appearance when viewed as a whole exterior wall. Therefore, there is a demand for the cured product of the curable composition to also exhibit antifouling effects over a long period of time.

[0006] Patent Document 2 discloses that the use of a diamine compound makes the surface of a cured product of a curable composition hydrophilic, thereby providing an antifouling effect due to a self-cleaning action. However, the diamine compound cannot provide an excellent antifouling effect for a long period of time.

[0007] Therefore, Patent Document 3 discloses that the use of a fluorine-containing surfactant in addition to a diamine compound can make the surface of the cured product of the curable composition more hydrophilic and improve the antifouling effect due to the self-cleaning action. However, the use of a fluorine-containing surfactant leads to a significant increase in price, making it impractical from a cost perspective. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 2008-1833 [Patent Document 2] Japanese Patent Application Laid-Open No. 2004-059870 [Patent Document 3] Japanese Patent Application Publication No. 2008-291159 Summary of the Invention [Problem to be solved by the invention]

[0009] Furthermore, in the case of a curable composition containing a diamine compound, when the surface of a cured product of the curable composition is observed obliquely, there is a problem that the surface reflects light such as sunlight, resulting in gloss. In such cases, the color tone of the cured product surface changes depending on the observation angle, which can be unpleasant for the observer and result in poor appearance. Therefore, it is necessary to impart antifouling properties to the cured product of the curable composition while reducing the occurrence of gloss.

[0010] The inventors have found that the combined use of a monoamine compound and a diamine compound reduces the gloss of a curable composition after curing and enables the composition to exhibit excellent antifouling properties over a long period of time. However, depending on the combination of the monoamine compound and the diamine compound, the color difference between the curable composition before and after curing may be large. For example, the color difference (ΔE) between the curable composition in the early stage of curing after application and the curable composition after complete or almost complete curing may be large. In such cases, the cured product of the curable composition may not have the desired color tone. Therefore, it is also necessary for the curable composition to have a small color difference between before and after curing.

[0011] Therefore, the present invention provides a curable composition that has a small color difference before and after curing, reduces the occurrence of gloss after curing, and is capable of exhibiting excellent antifouling effects over a long period of time. [Means for solving the problem]

[0012] The curable composition of the present invention is characterized by comprising a polymer (I) having a hydrolyzable silyl group, which includes a polyalkylene oxide (A) having a hydrolyzable silyl group, a monoamine compound (C), and a diamine compound, which includes a diamine compound (D) having a melting point that is equal to or lower than the melting point of the monoamine compound (C).

[0013] [Polymer (I)] The curable composition contains a polymer (I) having a hydrolyzable silyl group. The polymer (I) having a hydrolyzable silyl group makes it possible to provide a moisture-curable composition that can be cured by atmospheric moisture.

[0014] (Polyalkylene oxide (A)) The polymer (I) having a hydrolyzable silyl group contains a polyalkylene oxide (A) having a hydrolyzable silyl group. The polyalkylene oxide (A) has a hydrolyzable silyl group.

[0015] The hydrolyzable silyl group is a group formed by bonding 1 to 3 hydrolyzable groups to a silicon atom. The hydrolyzable group of the hydrolyzable silyl group is not particularly limited, and examples thereof include a hydrogen atom, a halogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an acid amide group, an aminooxy group, a mercapto group, and an alkenyloxy group.

[0016] As the hydrolyzable silyl group of the polyalkylene oxide (A), an alkoxysilyl group is preferred because the hydrolysis reaction is mild. Examples of the alkoxysilyl group include trialkoxysilyl groups such as trimethoxysilyl group, triethoxysilyl group, triisopropoxysilyl group, and triphenoxysilyl group; dialkoxysilyl groups such as methyldimethoxysilyl group and methyldiethoxysilyl group; and monoalkoxysilyl groups such as dimethylmethoxysilyl group and dimethylethoxysilyl group. Among these, as the hydrolyzable silyl group of the polyalkylene oxide (A), a dialkoxysilyl group is more preferred, and a methyldimethoxysilyl group is particularly preferred.

[0017] The polyalkylene oxide (A) preferably has 1 to 3, more preferably 1 to 2 hydrolyzable silyl groups on average per molecule. When the main chain of the polyalkylene oxide (A) is linear, the polyalkylene oxide (A) preferably has 1 to 2 hydrolyzable silyl groups on average per molecule. When the main chain of the polyalkylene oxide (A) is branched, the polyalkylene oxide (A) preferably has 1 to 3 hydrolyzable silyl groups on average per molecule. When the number of hydrolyzable silyl groups in the polyalkylene oxide (A) is 1 or more, the curability of the curable composition is improved. When the number of hydrolyzable silyl groups in the polyalkylene oxide (A) is the above-mentioned upper limit or less, the mechanical strength or elongation of the cured product of the curable composition is improved. Furthermore, the polyalkylene oxide (A) preferably has a hydrolyzable silyl group at at least one of both ends of its main chain.

[0018] The average number of hydrolyzable silyl groups per molecule in the polyalkylene oxide (A) is: 1 It can be calculated based on the concentration of hydrolyzable silyl groups in the polyalkylene oxide (A) determined by H-NMR and the number average molecular weight of the polyalkylene oxide (A) determined by GPC.

[0019] The polyalkylene oxide (A) may be a polyalkylene oxide having a main chain represented by the general formula: -(R 1 -O) n -(In the formula, R 1 represents an alkylene group having 1 to 14 carbon atoms, and n is the number of repeating units and is a positive integer.) The main chain skeleton of the polyalkylene oxide (A) may be composed of only one type of repeating unit, or may be composed of two or more types of repeating units.

[0020] Examples of the main chain skeleton of the polyalkylene oxide (A) include polyethylene oxide, polypropylene oxide, polybutylene oxide, polytetramethylene oxide, polyethylene oxide-polypropylene oxide copolymer, and polypropylene oxide-polybutylene oxide copolymer. Among these, polypropylene oxide is preferred. Polypropylene oxide can provide a curable composition that exhibits excellent rubber elasticity and adhesiveness after curing.

[0021] The number average molecular weight of the polyalkylene oxide (A) is preferably 15,000 to 50,000, more preferably 16,000 to 30,000. When the number average molecular weight of the polyalkylene oxide (A) is 15,000 or more, the mechanical strength or elongation of the cured product of the curable composition is improved. When the number average molecular weight of the polyalkylene oxide (A) is 50,000 or less, the coatability of the curable composition is improved.

[0022] In the present invention, the number average molecular weight of the polyalkylene oxide (A) refers to a value measured by gel permeation chromatography (GPC) in terms of polystyrene. In the GPC measurement, for example, a Shodex KF800D manufactured by Tosoh Corporation can be used as a GPC column, and chloroform or the like can be used as a solvent.

[0023] The polyalkylene oxide (A) containing a hydrolyzable silyl group can be commercially available. For example, examples of the polyalkylene oxide (A) having a polypropylene oxide main chain skeleton and a methyldimethoxysilyl group at the end of the main chain skeleton include those available under the trade names "Excestar S4530," "Excestar S2730C," and "Excestar S2420," all manufactured by Asahi Glass Co., Ltd.

[0024] The content of the polyalkylene oxide (A) in the polymer (I) having a hydrolyzable silyl group is preferably 20 to 100 mass%, more preferably 30 to 80 mass%, more preferably 40 to 70 mass%, and particularly preferably 55 to 70 mass%. By setting the content of the polyalkylene oxide (A) within the above range, the flexibility of the cured product of the curable composition is improved.

[0025] (Acrylic polymer (B)) The polymer (I) having a hydrolyzable silyl group preferably further contains an acrylic polymer (B) having a hydrolyzable silyl group. By using the acrylic polymer (B), the cured product of the curable composition can maintain excellent rubber elasticity for a long period of time.

[0026] The hydrolyzable silyl group contained in the acrylic polymer (B) is preferably an alkoxysilyl group, since the cured product of the curable composition can maintain excellent rubber elasticity for a long period of time. Examples of the alkoxysilyl group include trialkoxysilyl groups such as trimethoxysilyl, triethoxysilyl, triisopropoxysilyl, and triphenoxysilyl; dimethoxysilyl groups such as methyldimethoxysilyl and methyldiethoxysilyl; and monoalkoxysilyl groups such as dimethylmethoxysilyl and dimethylethoxysilyl. Among these, dialkoxysilyl and trialkoxysilyl groups are more preferred, trialkoxysilyl groups are more preferred, and trimethoxysilyl groups are particularly preferred.

[0027] Examples of the main chain skeleton of the acrylic polymer (B) include acrylic polymers obtained by radical polymerization of (meth)acrylate monomers such as ethyl (meth)acrylate, butyl (meth)acrylate, etc. Here, (meth)acrylate means methacrylate or acrylate.

[0028] Specific examples of the (meth)acrylate monomer constituting the main chain of the acrylic polymer (B) include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, and isomyristyl (meth)acrylate. Acrylate, stearyl (meth)acrylate, isobornyl (meth)acrylate, benzyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, glycidyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, hexanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, trime Examples of the acrylates include tyrolpropane tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy(meth)acrylate, polyester(meth)acrylate, urethane(meth)acrylate, 2-hydroxyethyl(meth)acrylate, 3-hydroxypropyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, 2-hydroxybutyl(meth)acrylate, 5-hydroxypentyl(meth)acrylate, 6-hydroxyhexyl(meth)acrylate, 3-hydroxy-3-methylbutyl(meth)acrylate, 2-hydroxy-3-phenoxypropyl(meth)acrylate, 2-[acryloyloxy]ethyl-2-hydroxyethyl phthalate, and 2-[acryloyloxy]ethyl-2-hydroxypropyl phthalate. These (meth)acrylate monomers may be used alone or in combination of two or more.

[0029] In the acrylic polymer (B), other monomers can also be copolymerized. Examples of such monomers include styrene derivatives such as styrene, indene, α-methylstyrene, p-methylstyrene, p-chlorostyrene, p-chloromethylstyrene, p-methoxystyrene, p-tert-butoxystyrene, and divinylbenzene; compounds having a vinyl ester group such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl benzoate, and vinyl cinnamate; maleic anhydride, N-vinylpyrrolidone, N-vinylmorpholine, (meth)acrylonitrile, (meth)acrylamide, N-cyclohexylmaleimide, N-phenylmaleimide, N-laurylmaleimide, N-benzylmaleimide, n-propyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, tert-amyl vinyl ether, cyclohexyl vinyl ether, 2-ethylhexyl vinyl ether, dodecyl vinyl ether, octadecyl vinyl ether, 2-chloroethyl vinyl ether, ethylene glycol butyl vinyl ether, and triethylene glycol butyl vinyl ether. Examples of vinyloxy groups include glycol methyl vinyl ether, (4-vinyloxy)butyl benzoate, ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, tetraethylene glycol divinyl ether, butane-1,4-diol divinyl ether, hexane-1,6-diol divinyl ether, cyclohexane-1,4-dimethanol divinyl ether, di(4-vinyloxy)butyl isophthalate, di(4-vinyloxy)butyl glutarate, di(4-vinyloxy)butyl succinate, trimethylolpropane trivinyl ether, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, 6-hydroxyhexyl vinyl ether, cyclohexane-1,4-dimethanol monovinyl ether, diethylene glycol monovinyl ether, 3-aminopropyl vinyl ether, 2-(N,N-diethylamino)ethyl vinyl ether, urethane vinyl ether, and polyester vinyl ether. These monomers may be used alone or in combination.

[0030] Among these, the main chain skeleton of the acrylic polymer (B) is preferably a copolymer of butyl (meth)acrylate and methyl (meth)acrylate, and more preferably a copolymer of butyl acrylate and methyl methacrylate. The acrylic polymer (B) having a main chain skeleton composed of the above copolymer can provide a curable composition that can form a cured product having both extensibility and flexibility after curing.

[0031] The polymerization method for the acrylic polymer (B) is not particularly limited, and any known method can be used, including various polymerization methods such as free radical polymerization, anionic polymerization, cationic polymerization, UV radical polymerization, living anionic polymerization, living cationic polymerization, and living radical polymerization.

[0032] The method for introducing a hydrolyzable silyl group into the acrylic polymer (B) is not particularly limited, and any known method can be used, such as a method of hydrosilylating an acrylic polymer having an unsaturated group introduced into the molecule by allowing a hydrosilane having a hydrolyzable silyl group to act on the polymer.

[0033] The number average molecular weight of the acrylic polymer (B) is preferably 1,000 to 50,000, more preferably 2,000 to 30,000. When the number average molecular weight of the acrylic polymer (B) is 50,000 or less, the coatability of the curable composition is improved. When the number average molecular weight of the acrylic polymer (B) is 1,000 or more, the mechanical strength or elongation of the cured product of the curable composition is improved.

[0034] In the present invention, the number average molecular weight of the acrylic polymer (B) refers to a value measured by gel permeation chromatography (GPC) in terms of polystyrene. In the GPC measurement, for example, a Tosoh Shodex KF800D GPC column and chloroform or the like can be used as a solvent.

[0035] The content of the acrylic polymer (B) in the polymer (I) having a hydrolyzable silyl group is preferably 20 to 70 mass%, more preferably 30 to 60 mass%, and particularly preferably 30 to 45 mass%. When the content of the acrylic polymer (B) is 20 mass% or more, the cured product of the curable composition maintains excellent rubber elasticity for a long period of time. When the content of the acrylic polymer (B) is 70 mass% or less, the coatability of the curable composition is improved.

[0036] [Monoamine compounds (C)] The curable composition of the present invention contains a monoamine compound (C). In the present invention, the monoamine compound refers to a compound having one amino group (-NH2) per molecule. In the monoamine compound, the hydrogen atom of the amino group may be substituted with an organic group such as an alkyl group or an aryl group. Furthermore, it is preferable that the monoamine compound (C) does not contain a silicon atom.

[0037] In the curable composition of the present invention, by using the monoamine compound (C) and the diamine compound in combination, the generation of gloss after curing is reduced and an excellent antifouling effect can be exhibited for a long period of time.

[0038] The melting point of the monoamine compound (C) is preferably 65°C or lower, more preferably 20 to 65°C, still more preferably 25 to 65°C, and particularly preferably 40 to 50°C. By adjusting the melting point of the monoamine compound (C) to 65°C or lower, the monoamine compound (C) can easily migrate to the surface of the cured product of the curable composition. This reduces the generation of gloss after curing and provides a curable composition that exhibits excellent antifouling effect over a long period of time. Furthermore, by adjusting the melting point of the monoamine compound (C) to 20°C or higher, the generation of tack on the surface of the cured product of the curable composition can be reduced.

[0039] When the curable composition contains a plurality of types of monoamine compounds (C), the melting points of the monoamine compounds (C) refer to the melting points of each of the monoamine compounds (C).

[0040] The melting point of the monoamine compound (C) refers to the temperature measured by differential scanning calorimetry (DSC) in accordance with JIS K7121 (1987). For example, the monoamine compound (C) is heated using a differential scanning calorimeter (e.g., a "DSC-60" manufactured by Shimadzu Corporation), and the melting peak temperature of the DSC curve during this heating process is taken as the melting point of the monoamine compound (C). The test specimen is conditioned in accordance with 3.(1) of JIS K7121 (1987). When there are multiple melting peaks, the melting point is taken as the temperature at the apex of the most endothermic melting peak.

[0041] Preferred examples of the monoamine compound (C) include monoamine compounds represented by the following formula (1). R 2 -NH2(1) (In formula (1), R 2 is a linear or branched alkyl group or a monovalent saturated alicyclic hydrocarbon group.

[0042] In formula (1), R 2 R is preferably a linear or branched alkyl group. 2 Examples of the linear or branched alkyl group in the formula (I) include a decyl group, an isodecyl group, an undecyl group, a lauryl group, an isododecyl group, a tridecyl group, a myristyl group, a pentadecyl group, a palmityl group, a heptadecyl group, an isohexadecyl group, a stearyl group, an isooctadecyl group, a nonadecyl group, an eicosyl group, and a behenyl group.

[0043] In the monoamine compound (C) represented by formula (1), R 2 The number of carbon atoms in R is preferably 12 to 40, more preferably 15 to 30, and particularly preferably 15 to 25. 2 By using the monoamine compound (C) having the number of carbon atoms within the above range, the tackiness of the surface of the cured product of the curable composition can be reduced in a short period of time, and the cured product of the curable composition can exhibit excellent antifouling effect over a long period of time.

[0044] Specific examples of the monoamine compound (C) include behenylamine (C 22 H 45 -NH2, melting point 63℃), stearylamine (C 18 H 37 -NH2, melting point 50℃), cetylamine (C 16 H 33 -NH2, melting point 47°C), myristylamine (C 14 H 29 -NH2, melting point 38°C), and laurylamine (C 12 H 25 —NH2, melting point 28° C.) Among these, behenylamine and stearylamine are preferred. The monoamine compound (C) may be used alone or in combination of two or more kinds.

[0045] The content of the monoamine compound (C) in the curable composition is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, and particularly preferably 1 to 5 parts by mass, per 100 parts by mass of the polymer (I) having a hydrolyzable silyl group. When the content of the monoamine compound (C) is 0.1 part by mass or more, the surface of the cured product of the curable composition can exhibit excellent antifouling effect for a long period of time. Furthermore, when the content of the monoamine compound (C) is 20 parts by mass or less, tackiness on the surface of the cured product of the curable composition at high temperatures can be reduced.

[0046] [Diamine compounds] The curable composition of the present invention contains a diamine compound. In the present invention, the diamine compound refers to a compound having two amino groups (-NH2) in one molecule. In the diamine compound, the hydrogen atoms of the amino groups may be substituted with organic groups such as alkyl groups or aryl groups. In addition, it is preferable that the diamine compound does not contain a silicon atom.

[0047] The diamine compound includes a diamine compound (D) having a melting point equal to or lower than that of the monoamine compound (C). By using such a diamine compound (D), it is possible to provide a curable composition that has a small color difference before and after curing and that exhibits reduced gloss after curing.

[0048] When the curable composition contains a plurality of diamine compounds, the melting points of the diamine compounds refer to the melting points of the individual diamine compounds.

[0049] In addition, in relation to "diamine compound (D) having a melting point lower than or equal to the melting point of monoamine compound (C)", when multiple types of monoamine compounds (C) are used, the diamine compound (D) having the lowest melting point (P Low ) monoamine compound (C Low ) above melting point (P Low ) or lower is referred to as "diamine compound (D)."

[0050] In the present invention, the melting point of a diamine compound refers to the temperature measured by differential scanning calorimetry (DSC) in accordance with JIS K7121 (1987). For example, a diamine compound is heated using a differential scanning calorimeter (e.g., a "DSC-60" manufactured by Shimadzu Corporation), and the melting peak temperature of the DSC curve during this heating process is taken as the melting point of the diamine compound. Conditioning of the test specimen is performed in accordance with 3.(1) of JIS K7121 (1987). When there are multiple melting peaks, the melting point is taken as the temperature at the apex of the melting peak with the greatest endothermic heat.

[0051] The melting point of the diamine compound (D) is preferably 65°C or lower, more preferably -1 to 65°C, more preferably 30 to 65°C, still more preferably 35 to 65°C, and particularly preferably 40 to 65°C. By setting the melting point of the diamine compound (D) to 65°C or lower, the diamine compound (D) can easily migrate to the surface of the cured product of the curable composition. This allows for the provision of a curable composition that exhibits reduced gloss after curing and excellent antifouling effects over a long period of time. Furthermore, by setting the melting point of the diamine compound (D) to -1°C or higher, the occurrence of tack on the surface of the cured product of the curable composition can be significantly reduced, thereby maintaining excellent antifouling effects. In particular, by setting the melting point of the diamine compound (D) to 30°C or higher, the occurrence of tack on the surface of the cured product of the curable composition can be significantly reduced even under high temperatures such as in summer, thereby maintaining excellent antifouling effects. The diamine compounds (D) may be used alone or in combination of two or more.

[0052] In the curable composition, the mass ratio of the monoamine compound (C) to the diamine compound (D) [mass of the monoamine compound (C):mass of the diamine compound (D)] is preferably 1:9 to 9:1, more preferably 2:8 to 8:2, and more preferably 3:7 to 7:3. When the mass ratio of the monoamine compound (C) to the diamine compound (D) is within the above range, it is possible to provide a curable composition that reduces the generation of gloss after curing and can exhibit excellent antifouling effect over a long period of time.

[0053] The content of the diamine compound (D) in the diamine compound is preferably 40% by mass or more, more preferably 50% by mass or more, and particularly preferably 90 to 100% by mass. By setting the content of the diamine compound (D) within the above range, it is possible to provide a curable composition that has a smaller color difference before and after curing and that exhibits less gloss after curing.

[0054] The diamine compound may further contain a diamine compound (E) having a melting point higher than that of the monoamine compound (C), within a range that does not adversely affect the properties of the curable composition. The content of the diamine compound (E) in the diamine compound is preferably 60 mass% or less, more preferably 50 mass% or less, and particularly preferably 0 to 10 mass%. A lower content of the diamine compound (E) can provide a curable composition that has a smaller color difference before and after curing and less gloss after curing.

[0055] In relation to "diamine compound (E) having a melting point higher than that of monoamine compound (C)", when multiple types of monoamine compounds (C) are used, the diamine compound (E) having the highest melting point (P High ) monoamine compound (C High ) above melting point (P High ) is referred to as "diamine compound (E)".

[0056] The diamine compound is preferably a diamine compound represented by the following formula (2). R 3 -NH-R 4 -NH2(2) (In formula (2), R 3 is a linear or branched alkyl group, an unsaturated aliphatic hydrocarbon group, a monovalent saturated alicyclic hydrocarbon group, or an aryl group, and R 4 is an alkylene group.

[0057] In equation (2), R 3 Examples of the linear or branched alkyl group in R include a decyl group, an isodecyl group, an undecyl group, a lauryl group, an isododecyl group, a tridecyl group, a myristyl group, a pentadecyl group, a palmityl group, a heptadecyl group, an isohexadecyl group, a stearyl group, an isooctadecyl group, a nonadecyl group, an eicosyl group, and a behenyl group. 3Examples of the unsaturated aliphatic hydrocarbon group in include an undecenyl group, a cis-4-tetradecenyl group, a cis-5-tetradecenyl group, a cis-9-tetradecenyl group, a cis-6-hexadecenyl group, a palmitoleyl group, a cis-6-octadecenyl group, an oleyl group, a trans-9-octadecenyl group, a cis-11-octadecenyl group, a trans-11-octadecenyl group, a myristoleyl group, a palmitoleyl group, and a linoleyl group.

[0058] In equation (2), R 4 is an alkylene group. 4 Examples of the alkylene group include a methylene group, an ethylene group, an ethylidene group, a trimethylene group, a propylene group, an isopropylene group, a tetramethylene group, a butylene group, an isobutylene group, a pentylene group, a hexamethylene group, and a hexylene group.

[0059] In the diamine compound represented by formula (2), R 3 and R 4 The total number of carbon atoms in R is preferably 15 to 40, more preferably 15 to 30, and particularly preferably 15 to 25. 3 and R 4 By setting the total number of carbon atoms within the above range, the surface of a cured product of the curable composition can exhibit an excellent antifouling effect for a long period of time, and the occurrence of tack on the surface of a cured product of the curable composition at high temperatures can be significantly reduced.

[0060] Specific examples of diamine compounds include behenyl propylene diamine (C 22 H 45 -NH-C3H6-NH2, melting point 63°C), and oleyl propylene diamine (C 18 H 35 -NH-C3H6-NH 2、 Melting point: 20°C). Among these, behenyl propylene diamine is preferred.

[0061] The content of the diamine compound in the curable composition is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, and particularly preferably 1 to 5 parts by mass, per 100 parts by mass of the polymer (I) having a hydrolyzable silyl group. When the content of the diamine compound is 0.1 part by mass or more, the surface of the cured product of the curable composition can exhibit excellent antifouling effect for a long period of time. Furthermore, when the content of the diamine compound is 20 parts by mass or less, the occurrence of tack on the surface of the cured product of the curable composition at high temperatures can be reduced.

[0062] [Plasticizer] The curable composition preferably further contains a plasticizer, specific examples of which include phthalate esters such as dioctyl phthalate, dibutyl phthalate, and butyl benzyl phthalate, polyalkylene oxides such as polypropylene glycol, and acrylic polymers, with acrylic polymers being preferred.

[0063] The acrylic polymer used as the plasticizer preferably does not have a hydrolyzable silyl group.

[0064] Examples of the main chain skeleton of the acrylic polymer used as the plasticizer include acrylic polymers obtained by radical polymerization of (meth)acrylate monomers.

[0065] Specific examples of (meth)acrylate monomers constituting the main chain of acrylic polymers used as plasticizers include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, and isomyristyl (meth)acrylate. (meth)acrylate, stearyl (meth)acrylate, isobornyl (meth)acrylate, benzyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, glycidyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, hexanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate , trimethylolpropane tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy(meth)acrylate, polyester(meth)acrylate, urethane(meth)acrylate, 2-hydroxyethyl(meth)acrylate, 3-hydroxypropyl(meth)acrylate, 2-hydroxypropyl(meth)acrylate acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 3-hydroxy-3-methylbutyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-[acryloyloxy]ethyl-2-hydroxyethyl phthalate, and 2-[acryloyloxy]ethyl-2-hydroxypropyl phthalate. These (meth)acrylate monomers may be used alone or in combination of two or more.

[0066] The weight-average molecular weight of the acrylic polymer used as a plasticizer is preferably 1,000 to 50,000, more preferably 2,000 to 30,000. When the weight-average molecular weight of the acrylic polymer used as a plasticizer is 50,000 or less, the coatability of the curable composition is improved. When the weight-average molecular weight of the acrylic polymer used as a plasticizer is 1,000 or more, the mechanical strength or elongation of the cured product of the curable composition is improved.

[0067] In the present invention, the weight-average molecular weight of the acrylic polymer used as a plasticizer refers to a value measured by gel permeation chromatography (GPC) in terms of polystyrene. In the GPC measurement, for example, a Shodex KF800D manufactured by Tosoh Corporation can be used as a GPC column, and chloroform or the like can be used as a solvent.

[0068] The content of the plasticizer in the curable composition is preferably 100 parts by mass or less, more preferably 70 parts by mass or less, more preferably 1 to 70 parts by mass, and particularly preferably 20 to 50 parts by mass, relative to 100 parts by mass of the polymer (I) having a hydrolyzable silyl group. If the content of the plasticizer is too high, the plasticizer may precipitate on the surface of the cured product of the curable composition.

[0069] [Filler] The curable composition preferably further contains a filler, which makes it possible to provide a curable composition that can give a cured product having excellent mechanical strength.

[0070] Examples of fillers include calcium carbonate, magnesium carbonate, calcium oxide, hydrous silicic acid, anhydrous silicic acid, finely powdered silica, calcium silicate, titanium dioxide, clay, talc, carbon black, and glass balloons. These fillers may be used alone or in combination of two or more. Of these, calcium carbonate is preferably used.

[0071] The average particle size of calcium carbonate is preferably 0.01 to 5 μm, more preferably 0.05 to 2.5 μm. Calcium carbonate having such an average particle size can provide a cured product having excellent mechanical strength and elongation, and can also provide a curable composition having excellent adhesiveness.

[0072] The calcium carbonate is preferably surface-treated with a fatty acid, a fatty acid ester, etc. Calcium carbonate surface-treated with a fatty acid, a fatty acid ester, etc. can impart thixotropy to the hardenable composition and can also inhibit aggregation of calcium carbonate.

[0073] The content of the filler in the curable composition is preferably 1 to 700 parts by mass, more preferably 10 to 200 parts by mass, per 100 parts by mass of the polymer (I) having a hydrolyzable silyl group. When the content of the filler is 1 part by mass or more, the effect of adding the filler is sufficiently obtained. Furthermore, when the content of the filler is 700 parts by mass or less, the cured product obtained by curing the curable composition has excellent elongation.

[0074] [Dehydrating agent] The curable composition preferably further contains a dehydrating agent, which can prevent the curable composition from being cured by moisture contained in the air or the like during storage.

[0075] Examples of dehydrating agents include silane compounds such as vinyltrimethoxysilane, dimethyldimethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, tetramethoxysilane, phenyltrimethoxysilane, and diphenyldimethoxysilane; and ester compounds such as methyl orthoformate, ethyl orthoformate, methyl orthoacetate, and ethyl orthoacetate. These dehydrating agents may be used alone or in combination. Among them, vinyltrimethoxysilane is preferred.

[0076] The content of the dehydrating agent in the curable composition is preferably 0.5 to 20 parts by mass, more preferably 1 to 15 parts by mass, per 100 parts by mass of the polymer (I) having a hydrolyzable silyl group. When the content of the dehydrating agent is 0.5 parts by mass or more, the effect of the dehydrating agent can be sufficiently obtained. Furthermore, when the content of the dehydrating agent is 20 parts by mass or less, the curable composition has excellent curability.

[0077] [Silanol condensation catalyst] The curable composition preferably contains a silanol condensation catalyst, which is a catalyst for promoting a dehydration condensation reaction between silanol groups formed by hydrolysis of hydrolyzable silyl groups contained in the polymer (I).

[0078] Examples of silanol condensation catalysts include organic tin compounds such as 1,1,3,3-tetrabutyl-1,3-dilauryloxycarbonyl-distannoxane, dibutyltin dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin phthalate, bis(dibutyltin laurate) oxide, dibutyltin bis(acetylacetonate), dibutyltin bis(monoester maleate), tin octoate, dibutyltin octoate, dioctyltin oxide, dibutyltin bis(triethoxysilicate), bis(dibutyltin bistriethoxysilicate) oxide, and dibutyltin oxybisethoxysilicate; and organic titanium compounds such as tetra-n-butoxytitanate and tetraisopropoxytitanate. These silanol condensation catalysts may be used alone or in combination of two or more.

[0079] The silanol condensation catalyst is preferably 1,1,3,3-tetrabutyl-1,3-dilauryloxycarbonyl-distannoxane, which makes it possible to easily adjust the curing rate of the curable composition.

[0080] The content of the silanol condensation catalyst in the curable composition is preferably 1 to 10 parts by mass, more preferably 1 to 5 parts by mass, per 100 parts by mass of the polymer (I) having a hydrolyzable silyl group. When the content of the silanol condensation catalyst is 1 part by mass or more, the curing rate of the curable composition can be increased, thereby shortening the time required for curing the curable composition. When the content of the silanol condensation catalyst is 10 parts by mass or less, the curable composition has an appropriate curing rate, and the storage stability and handleability of the curable composition can be improved.

[0081] [Other additives] The curable composition may contain other additives such as a thixotropic agent, an antioxidant, an ultraviolet absorber, a pigment, a dye, an anti-settling agent, and a solvent. Among these, the thixotropic agent, the ultraviolet absorber, and the antioxidant are preferred.

[0082] [Thixotropic agent] The thixotropy-imparting agent may be any agent capable of imparting thixotropy to the curable composition, and preferred examples of the thixotropy-imparting agent include hydrogenated castor oil, fatty acid bisamide, and fumed silica.

[0083] The content of the thixotropy-imparting agent in the curable composition is preferably 0.1 to 200 parts by mass, more preferably 1 to 150 parts by mass, per 100 parts by mass of the polymer (I) having a hydrolyzable silyl group. When the content of the thixotropy-imparting agent is 0.1 part by mass or more, thixotropy can be effectively imparted to the curable composition. Furthermore, when the content of the thixotropy-imparting agent is 200 parts by mass or less, the curable composition has an appropriate viscosity, improving the handleability of the curable composition.

[0084] [UV absorber] Examples of the ultraviolet absorber include a benzotriazole-based ultraviolet absorber and a benzophenone-based ultraviolet absorber, and the benzotriazole-based ultraviolet absorber is preferred. The content of the ultraviolet absorber in the curable composition is preferably 0.1 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, per 100 parts by mass of the polymer (I) having a hydrolyzable silyl group.

[0085] [Antioxidants] Examples of the antioxidant include hindered phenol antioxidants, monophenol antioxidants, bisphenol antioxidants, and polyphenol antioxidants, and the hindered phenol antioxidants are preferred. The content of the antioxidant in the curable composition is preferably 0.1 to 20 parts by mass, more preferably 0.3 to 10 parts by mass, per 100 parts by mass of the polymer (I) having a hydrolyzable silyl group.

[0086] [Light stabilizer] The curable composition preferably contains a hindered amine light stabilizer, which can provide a curable composition that can maintain excellent rubber elasticity for a longer period of time after curing.

[0087] Examples of hindered amine light stabilizers include a mixture of bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, dibutylamine·1,3,5-triazine·N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl-1,6-hexamethylenediamine) and N-(2,2,6,6 poly[{6-(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine-2,4-diyl}{(2,2,6,6-tetramethyl-4-piperidyl)imino}hexamethylene{(2,2,6,6-tetramethyl-4-piperidyl)imino}], and a polycondensate of dimethyl succinate and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol.

[0088] Preferred examples of the hindered amine light stabilizer include NOR-type hindered amine light stabilizers, which can provide a curable composition that is inhibited from decreasing in rubber elasticity over time after curing.

[0089] The NOR hindered amine light stabilizer has a NOR structure in which an alkyl group (R) is bonded to a nitrogen atom (N) contained in a piperidine ring skeleton via an oxygen atom (O). The number of carbon atoms in the alkyl group in the NOR structure is preferably 1 to 20, more preferably 1 to 18, and particularly preferably 18. Examples of the alkyl group include a linear alkyl group, a branched alkyl group, and a cyclic alkyl group (a saturated alicyclic hydrocarbon group).

[0090] Examples of linear alkyl groups include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-octyl, n-nonyl, and n-decyl groups. Examples of branched alkyl groups include isopropyl, isobutyl, sec-butyl, and tert-butyl groups. Examples of cyclic alkyl groups (saturated alicyclic hydrocarbon groups) include cyclopentyl, cyclohexyl, and cyclooctyl groups. In addition, the hydrogen atoms constituting the alkyl groups may be substituted with halogen atoms (e.g., fluorine, chlorine, and bromine atoms) or hydroxyl groups.

[0091] Examples of the NOR type hindered amine light stabilizer include hindered amine light stabilizers represented by the following formula (I).

[0092] [ka]

[0093] When a NOR type hindered amine light stabilizer is used, it is preferable to use the NOR type hindered amine light stabilizer in combination with a benzotriazole type ultraviolet absorber or a triazine type ultraviolet absorber, which can provide a curable composition in which the decrease in rubber elasticity over time after curing is more significantly suppressed.

[0094] The content of the hindered amine light stabilizer in the curable composition is preferably from 0.01 to 20 parts by mass, more preferably from 0.1 to 10 parts by mass, based on 100 parts by mass of the polymer (I) having a hydrolyzable silyl group.

[0095] [Aminosilane coupling agent] The curable composition of the present invention preferably contains an aminosilane coupling agent. By using the aminosilane coupling agent, the rubber elasticity and adhesiveness of the cured product of the curable composition can be improved. The aminosilane coupling agent means a compound containing a silicon atom to which an alkoxy group is bonded and a functional group containing a nitrogen atom in one molecule.

[0096] Specific examples of aminosilane coupling agents include 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, N,N'-bis-[3-(trimethoxysilyl)propyl]ethylenediamine, N,N'-bis-[3-(triethoxysilyl)propyl]ethylenediamine, N,N'-bis-[3-(methyldimethoxysilyl)propyl]ethylenediamine, N,N'-bis-[3-(trimethoxysilyl)propyl]hexamethylenediamine, and N,N'-bis-[3-(triethoxysilyl)propyl]hexamethylenediamine. These aminosilane coupling agents may be used alone or in combination of two or more.

[0097] Among these, preferred examples of the aminosilane coupling agent include 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, and N-(2-aminoethyl)-3-aminopropyltriethoxysilane, and more preferred example is N-(2-aminoethyl)-3-aminopropyltrimethoxysilane. do.

[0098] The content of the aminosilane coupling agent in the curable composition is preferably 1 to 10 parts by mass, more preferably 1 to 5 parts by mass, per 100 parts by mass of the polymer (I) having a hydrolyzable silyl group. When the content of the aminosilane coupling agent is within the above range, the rubber elasticity and adhesiveness of the cured product of the curable composition can be improved.

[0099] The curable composition of the present invention has excellent adhesive properties and can form a cured product that can maintain excellent rubber elasticity for a long period of time, and therefore can be used in various applications such as sealants, coating materials, adhesives, and paints.

[0100] In particular, the curable composition of the present invention has a small color difference before and after curing, making it easy to adjust the color to a desired color after curing. For example, it is possible to reduce the color difference (ΔE) between a curable composition in the early stage of curing after application and a curable composition that has completed or nearly completed curing. Furthermore, the curable composition of the present invention has an antifouling effect while reducing the occurrence of gloss due to reflection of light such as sunlight, and therefore can maintain a beautiful appearance for a long period of time, especially when used outdoors. Therefore, the curable composition of the present invention is preferably used as a sealant or adhesive, and more preferably as a sealant for joint structures.

[0101] A method of applying a curable composition to a joint portion to obtain a joint structure involves filling the joint portion with the curable composition and then curing the composition to harden it. The resulting joint structure comprises wall members that constitute the walls of an architectural structure and a cured product of the curable composition that has been filled into the joint portion formed between adjacent wall members. Examples of the wall portion of an architectural structure include exterior walls, interior walls, and ceiling portions, with exterior walls being preferred. Examples of wall members include exterior wall members, interior wall members, and ceiling members, with exterior wall members being preferred.

[0102] The joints are not particularly limited, and examples thereof include joints in the exterior walls, interior walls, and ceilings of building structures. The curable composition of the present invention can maintain an excellent antifouling effect for a long period of time after curing. Therefore, it is suitable for sealing so-called "working joints," such as joints in the exterior walls of building structures, which are easily soiled by dust and pollutants.

[0103] Examples of joints in the exterior walls of building structures include joints that occur at the joints between exterior wall components such as mortar boards, concrete boards, ceramic siding boards, metal siding boards, ALC boards, and metal plates. [Effects of the Invention]

[0104] The curable composition of the present invention has the above-described structure, and therefore has a small color difference before and after curing, reduced gloss after curing, and can exhibit excellent antifouling effect for a long period of time. Therefore, the cured product of the curable composition can have a desired color tone and can maintain a beautiful appearance for a long period of time. DETAILED DESCRIPTION OF THE INVENTION

[0105] The present invention will be described in more detail below using examples, but the present invention is not limited to these examples. [Example]

[0106] The following raw materials were used in producing the curable compositions of the Examples and Comparative Examples. [Polymer (I) having hydrolyzable silyl groups] (Polyalkylene oxide (A) having a hydrolyzable silyl group) Polyalkylene oxide (A1) (a polyalkylene oxide having methyldimethoxysilyl groups and a polypropylene oxide main chain, manufactured by Asahi Glass Co., Ltd., trade name "Excestar S2420", average number of methyldimethoxysilyl groups per molecule: 1.7, molecular weight distribution: 1.49, number average molecular weight: 18,990)

[0107] (Acrylic polymer (B) having hydrolyzable silyl group) Acrylic polymer (B1) (an acrylic polymer having a main chain skeleton composed of a methyl methacrylate-n-butyl acrylate copolymer (methyl methacrylate content: 25% by mass, n-butyl acrylate content: 75% by mass), and having a trimethoxysilyl group at the end of the main chain skeleton or in a side chain, number average molecular weight: 2,400)

[0108] [Monoamine compounds (C)] Monoamine compound (C1) (stearylamine, melting point 50°C, Kao Corporation, trade name "Furmin 80S") Monoamine compound (C2) (behenylamine, melting point 63°C, NOF Corporation, trade name "Nissanamine VB-S")

[0109] [Diamine compounds] -Hydrogenated tallow propylene diamine (manufactured by NOF Corporation, product name "Nissan Amine DT-H") Behenyl propylene diamine (melting point 63°C, product name "Nissan Amine DV" manufactured by NOF Corporation)

[0110] The above-mentioned hardened beef tallow propylene diamine (manufactured by NOF Corporation under the trade name "Nissanamine DT-H") is a compound represented by the above formula (2) (wherein R 3 is a linear alkyl group having 15 to 18 carbon atoms, and R 4 is a propylene group) and has a melting point of 64 to 80°C, and 3 is a linear alkyl group having 13 to 14 carbon atoms, and R 4 is a propylene group) and has a melting point of 53 to 60°C, and 3 is an unsaturated aliphatic hydrocarbon group having 15 to 18 carbon atoms, and R 4 is a propylene group) and contained 45 to 51 mass % of a diamine compound having a melting point of -1 to 28°C.

[0111] [Plasticizer] Plasticizer (1) (acrylic polymer not containing a hydrolyzable silyl group, weight-average molecular weight: 3,500, manufactured by Toagosei Co., Ltd., product name "UP-1110")

[0112] [Filler] Colloidal calcium carbonate (average particle size: 80 nm, surface treatment with fatty acid, manufactured by Maruo Calcium Co., Ltd., product name "Calcine 200M") Heavy calcium carbonate (average particle size: 1.0 μm, surface treated with fatty acid, manufactured by Nitto Funka Co., Ltd., product name "NCC2310")

[0113] [Dehydrating agent] Vinyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., product name "KBM-1003")

[0114] [Silanol condensation catalyst] Silanol condensation catalyst (1,1,3,3-tetrabutyl-1,3-dilauryloxycarbonyl-distannoxane, manufactured by Nitto Kasei Co., Ltd., product name "Neostan U-130")

[0115] [UV absorber] Benzotriazole-based UV absorber (product name "Tinuvin 326" manufactured by BASF Japan Ltd.)

[0116] [Antioxidants] Hindered phenol antioxidant (BASF Japan, product name "Irganox 1010")

[0117] [Light stabilizer] NH-type hindered amine light stabilizer (product name "Tinuvin 770" manufactured by BASF Japan Ltd.)

[0118] [Other additives] Aminosilane coupling agent (N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, product name "KBM-603" manufactured by Shin-Etsu Chemical Co., Ltd.) Thixotropic agent (fatty acid amide wax, manufactured by Kusumoto Chemicals Co., Ltd., product name "Disparlon #6500") )

[0119] [solvent] Ethylene glycol tertiary butyl ether (ETB)

[0120] (Examples 1 to 4, Comparative Examples 1 to 8) The polyalkylene oxide (A1), acrylic polymer (B1), monoamine compound (C1), monoamine compound (C2), hardened beef tallow propylene diamine, behenyl propylene diamine, plasticizer (1), colloidal calcium carbonate, heavy calcium carbonate, vinyltrimethoxysilane, silanol condensation catalyst, benzotriazole-based UV absorber, hindered phenol-based antioxidant, NH-type hindered amine-based light stabilizer, aminosilane coupling agent, thixotropic agent, and ethylene glycol tertiary butyl ether (ETB) were mixed in the amounts shown in Table 1 in a sealed mixer under reduced pressure until the mixture was uniform, thereby obtaining a curable composition.

[0121] [evaluation] The resulting curable compositions were evaluated for gloss, color difference, and antifouling effect immediately after curing and after a long-term exposure test according to the following procedures.

[0122] Glossiness The curable composition was applied to a stainless steel plate to a thickness of 5 mm in an atmosphere of 23°C and 50% relative humidity and then cured for one day. The gloss was measured using a gloss meter (manufactured by Tasco Japan Co., Ltd., product name "Gloss Checker TMS724") when light was incident at an angle of 20 or 60 degrees onto the cured surface of the curable composition, and evaluated according to the following criteria. The results are shown in Table 1. Note that a lower gloss value indicates a lower light reflectance and a lower glossiness of the cured surface. ◯: Glossiness was 3 or less. ×: Glossiness was greater than 3.

[0123] [Color difference] The curable composition was applied to a thickness of 5 mm under an atmosphere of 23°C and 50% relative humidity and aged for 8 hours to obtain a sheet-like cured product (I). Separately, the curable composition was applied to a thickness of 5 mm under an atmosphere of 23°C and 50% relative humidity and aged for 14 days to obtain a sheet-like cured product (II). Colorimetry of the surfaces of the cured products (I) and (II) was performed using a spectrophotometer (manufactured by Konica Minolta Japan, Inc., product name "CM-2500d") in accordance with JIS K5600-4-5 (1999). The color difference (ΔE) of the cured products (I) and (II) was calculated in accordance with JIS K5600-4-6 (1999) and evaluated according to the following criteria. The results are shown in Table 1. ◯: The color difference (ΔE) was less than 2.0. ×: The color difference (ΔE) was 2.0 or more.

[0124] [Anti-fouling effect (immediately after curing)] The curable composition was applied to a stainless steel plate to a thickness of 5 mm in an atmosphere of 23°C and 50% relative humidity and cured for one day. No. 7 silica sand was sprinkled on the surface of the cured curable composition, and the presence or absence of silica sand was visually observed and evaluated according to the following criteria. The results are shown in the "Anti-fouling effect (immediately after curing)" column in Table 1. ◎ No silica sand was attached. ○: The number of silica sand particles attached per 5cm square was 1 particle or more and less than 50 particles. △···The number of silica sand particles adhering per 5 cm square was 50 or more and less than 200 particles. × The number of silica sand particles attached per 5cm square was 200 or more.

[0125] [Anti-fouling effect (after long-term exposure test)] A 5 mm thick coating of the curable composition was applied to a release-treated polyethylene terephthalate (PET) substrate at 23°C and 50% relative humidity and then cured for one day. A sheet-like specimen consisting of the cured product of the curable composition was then prepared on the PET substrate. The PET substrate was then peeled from the sheet-like specimen, and the sheet-like specimen alone was attached to an aluminum plate to obtain a laminate. The laminate was then exposed outdoors (Koga City, Shiga Prefecture) for three months, with the surface of the sheet-like specimen facing north at a 45° inclination angle to the horizontal. After exposure, the degree of adhesion of dust, sand, and other contaminants to the surface of the sheet-like specimen was visually observed and evaluated according to the following criteria. The results are shown in the "Anti-fouling Effect (After Long-Term Exposure Test)" column in Table 1. ◎: No dirt was attached. ○: Although there was a small amount of dirt, the condition was good. △: Although there is dirt attached, it does not cause any problems in actual use. ×: The entire surface was covered with dirt and was in a very dirty state.

[0126] [Table 1] TIFF0007723399000002.tif222153 [Industrial Applicability]

[0127] The curable composition of the present invention has a small color difference before and after curing, reduces gloss generation after curing, and maintains excellent antifouling effect for a long period of time, and therefore can be suitably used, for example, as a filler for joints formed between exterior wall members that constitute the exterior walls of building structures.

Claims

1. a polymer (I) having a hydrolyzable silyl group, which contains a polyalkylene oxide (A) having a hydrolyzable silyl group; and R 2 -NH 2 and a monoamine compound (C) having a melting point lower than or equal to the melting point of the monoamine compound (C) and represented by R 3 -NH-R 4 -NH 2 and a diamine compound (D) represented by the formula: 2 is a linear or branched alkyl group or a monovalent saturated alicyclic hydrocarbon group, and R 3 is a linear or branched alkyl group, an unsaturated aliphatic hydrocarbon group, a monovalent saturated alicyclic hydrocarbon group, or an aryl group, and R 4 is an alkylene group.

2. 2. The curable composition according to claim 1, wherein the polymer (I) having a hydrolyzable silyl group contains an acrylic polymer (B) having a hydrolyzable silyl group.

3. 3. The curable composition according to claim 1, wherein the monoamine compound (C) has a melting point of 65°C or lower.

4. 4. The curable composition according to claim 1, wherein a mass ratio of the monoamine compound (C) to the diamine compound (D) [mass of the monoamine compound (C):mass of the diamine compound (D)] is 1:9 to 9:

1.

5. A sealant comprising the curable composition according to any one of claims 1 to 4.

6. An adhesive comprising the curable composition according to any one of claims 1 to 4.

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