Hardening components

Abstract

The present invention provides a curable composition that exhibits excellent dispersibility, thixotropy, surface tack prevention, and rubber properties. [Solution] A curable composition containing a curable resin, hydrophilic silica, and polyether-modified silicone.

Description

[Technical Field]

[0001] The present invention relates to a curable composition that exhibits excellent dispersibility, thixotropy, surface tack prevention, and rubber properties. [Background technology]

[0002] Conventionally, curable resins such as isocyanate group-containing resins and modified silicone resins have been widely used as curing components in sealing materials, adhesives, and coatings for building and civil engineering applications. In these applications, since they are sometimes used on vertical or inclined surfaces, it is necessary to impart thixotropy to the curable composition. For example, sealing materials applied to exterior wall joints and ceiling joints require thixotropy to prevent sagging (slump) during and after application.

[0003] A known method for imparting thixotropy to a curable composition is to incorporate a thixotropizing agent, such as surface-treated calcium carbonate or finely powdered silica, into the curable composition (for example, Patent Documents 1 and 2). However, there are various challenges in incorporating thixotropizing agents. For example, if a large amount of thixotropizing agent is used to impart sufficient thixotropy to the curable composition, the dispersibility of the composition deteriorates, and the degree of freedom in designing the composition's formulation decreases. In addition, the moisture contained in the thixotropizing agent may worsen the storage stability of the curable composition.

[0004] On the other hand, when a curable composition is designed to exhibit specific rubber properties ranging from low to medium modulus, stickiness (surface tack) may remain on the cured surface. In this case, dust and dirt easily adhere to the cured surface, causing contamination and resulting in design defects. In particular, when a curable composition is used outdoors or while it is still curing, if the surface is very sticky (surface tack), a lot of dust and dirt will adhere to it, causing significant contamination. Therefore, it is desirable to minimize surface tack as much as possible. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2004-182934 [Patent Document 2] Japanese Patent Publication No. 2010-1380 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The object of the present invention is to provide a curable composition that exhibits excellent dispersibility, thixotropy, surface tack prevention, and rubber properties. [Means for solving the problem]

[0007] As a result of diligent research to solve the above-mentioned problems, the inventors of the present invention have found that a curable composition containing a curable resin, hydrophilic silica, and polyether-modified silicone exhibits excellent dispersibility, thixotropy, surface tack prevention, and rubber properties, and have completed the present invention.

[0008] In other words, the gist of the composition of the curable composition according to the present invention is shown in the following [1] to

[11] . [1] A curable composition containing a curable resin, hydrophilic silica, and polyether-modified silicone. [2] The curable composition according to [1] above, wherein the curable resin is an isocyanate group-containing resin or a crosslinkable silyl group-containing resin. [3] The aforementioned hydrophilic silica, 50m 2 / g or more 500m 2 The curable composition according to [1] above, having a BET specific surface area of ​​0.5% by mass or less and a carbon content of 0.5% by mass or less. [4] The curable composition according to [1] above, wherein the polyether-modified silicone has polyoxyalkylene groups in at least one side chain of the polysiloxane skeleton. [5] The curable composition according to [4] above, wherein the polyoxyalkylene group is a polyoxyethylene group and / or a polyoxypropylene group. [6] The curable composition according to [1] above, wherein the number average molecular weight of the polyether-modified silicone is 2,000 or more and 8,000 or less. [7] The amount of hydrophilic silica blended is 1 part by mass or more and 20 parts by mass or less per 100 parts by mass of the curable resin, and The curable composition according to [1] above, wherein the amount of polyether-modified silicone blended is 1 part by mass or more and 70 parts by mass or less per 100 parts by mass of hydrophilic silica. [8] The curable composition according to [1] above, further containing a polyurea compound. [9] The curable composition according to [1] above, further comprising at least one additive selected from the group consisting of a curing accelerator, a plasticizer, a weather stabilizer, a filler, a thixotropy-imparting agent (excluding hydrophilic silica and polyurea compounds), an adhesion enhancer, a storage stability enhancer (dehydrating agent), a colorant, and an organic solvent.

[10] The curable composition according to any one of [1] to [9] above, wherein the curable composition is a curable composition for building or civil engineering.

[11] The curable composition according to any one of [1] to [9] above, wherein the curable composition is a sealant composition, a putty composition, a waterproofing composition, an adhesive composition, or a coating composition. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a curable composition with excellent dispersibility, thixotropy, surface tack prevention, and rubber properties.

[0010] Embodiments of the present invention will be described in detail below. The curable composition of the present invention contains a curable resin, hydrophilic silica, and polyether-modified silicone. Each component of the curable composition will be described in detail below.

[0011] <Curable resin> The curable resin has the property of curing by reacting with an active hydrogen-containing compound etc. (e.g., water such as moisture) at normal temperature. Here, normal temperature means the normal temperature (5 to 35°C) described in JIS Z 8703 (1983). Also, even if it is a curable resin that reacts with an active hydrogen-containing compound etc. and crosslink-cures at a temperature below 5°C or above 35°C, it is included in the curable resin as long as it reacts with an active hydrogen-containing compound etc. and crosslink-cures at normal temperature (5 to 35°C).

[0012] The curable resin is not particularly limited as long as it reacts with an active hydrogen-containing compound etc. at normal temperature and crosslink-cures. Specific examples of such curable resins include isocyanate group-containing resins or crosslinkable (hydrolyzable) silyl group-containing resins.

[0013] <Isocyanate group-containing resin> The isocyanate group-containing resin is a resin having one or more isocyanate groups in the resin. The isocyanate group reacts with an active hydrogen-containing compound to form a urethane bond, a urea bond, etc. and crosslink-cures. Preferred examples of the isocyanate group-containing resin include isocyanate group-containing urethane prepolymers (hereinafter, sometimes simply referred to as "urethane prepolymers" including the isocyanate group-containing urethane prepolymers and the isocyanate group-containing urethane prepolymers into which a photoreactive unsaturated bond described later is introduced).

[0014] An isocyanate group-containing urethane prepolymer can be manufactured by reacting an organic isocyanate compound and an active hydrogen-containing compound all at once or sequentially, with a molar ratio of isocyanate group / active hydrogen preferably greater than 1.0, more preferably 1.2 or more from the viewpoint of preventing the viscosity of the urethane prepolymer from increasing and reducing the workability of the curable composition, and 10 or less from the viewpoint of reducing the amount of carbon dioxide generated by the reaction of the isocyanate group with water and preventing foaming during curing, and particularly preferably in the range of 1.2 to 5, so that isocyanate groups remain in the urethane prepolymer.

[0015] The isocyanate group content in the isocyanate group-containing urethane prepolymer is preferably 0.3% by mass or more, from the viewpoint of preventing the viscosity of the urethane prepolymer from increasing and reducing the workability of the curable composition, more preferably 15% by mass or less, and particularly preferably in the range of 0.5% by mass or more and 5% by mass or less, from the viewpoint of reducing the amount of carbon dioxide generated by the reaction of the isocyanate group with water and preventing foaming during curing.

[0016] The number-average molecular weight of the isocyanate group-containing urethane prepolymer is preferably 700 or more, more preferably 700 to 20,000, even more preferably 700 to 15,000, and particularly preferably 700 to 10,000.

[0017] The number-average molecular weight is a polystyrene-converted value measured by gel permeation chromatography (GPC). The specific measurement conditions are shown below. Equipment name: HLC-8320GPC (manufactured by Tosoh Corporation) Eluent: THF (tetrahydrofuran) Temperature: 40℃ Detector: RI

[0018] Isocyanate group-containing urethane prepolymers can be manufactured by conventionally known methods. Specifically, this method involves charging an organic isocyanate compound and an active hydrogen-containing compound into a reaction vessel made of glass or stainless steel, adding a reaction catalyst and organic solvent as needed, and reacting them while stirring at a temperature of 50 to 120°C. In this case, since the viscosity of the urethane prepolymer increases when the isocyanate group reacts with water such as moisture, it is preferable to replace the inside of the vessel with nitrogen gas beforehand or to carry out the reaction under a nitrogen gas stream.

[0019] Examples of organic isocyanate compounds include organic polyisocyanates. Organic polyisocyanates are compounds that have two or more isocyanate groups in their composition. Specifically, these include toluene polyisocyanates such as 2,4-toluene diisocyanate and 2,6-toluene diisocyanate; diphenylmethane polyisocyanates such as 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate and 2,2'-diphenylmethane diisocyanate; and 1,2-phenylenediisocyanate, 1,3-phenylenediisocyanate, 1,4-phenylenediisocyanate, 2,4,6-trimethylphenyl-1,3-diisocyanate, 2,4, Examples include phenylene polyisocyanates such as 6-triisopropylphenyl-1,3-diisocyanate; naphthalene polyisocyanates such as 1,4-naphthalene diisocyanate and 1,5-naphthalene diisocyanate; and aromatic polyisocyanates such as chlorophenylene-2,4-diisocyanate, 4,4'-diphenyl ether diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, and 3,3'-dimethoxydiphenyl-4,4'-diisocyanate.

[0020] Other examples of organic polyisocyanates include aliphatic polyisocyanates such as 1,6-hexamethylene diisocyanate, 1,5-pentamethylene diisocyanate, 1,4-tetramethylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 2,4,4-trimethyl-1,6-hexamethylene diisocyanate, decamethylene diisocyanate, and lysine diisocyanate; o-xylylene diisocyanate, m-xylylene Examples include aromatic aliphatic polyisocyanates such as diisocyanate and p-xylylene diisocyanate; alicyclic polyisocyanates such as 1,4-cyclohexyl diisocyanate, isophorone diisocyanate, hydrogenated toluene diisocyanate, hydrogenated xylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate; and polymeric isocyanates such as polymethylene polyphenyl polyisocyanate and crude toluene diisocyanate. Furthermore, modified polyisocyanates obtained by modifying these organic polyisocyanates may have one or more uretdione bonds, isocyanurate bonds, allophanate bonds, biuret bonds, uretonimine bonds, carbodiimide bonds, urethane bonds, or urea bonds. Any of the above-mentioned organic polyisocyanates may be used individually or in combination of two or more.

[0021] When using a curable composition in a location exposed to sunlight (ultraviolet rays), it is preferable to use at least one organic polyisocyanate selected from the group consisting of aliphatic polyisocyanates, aromatic aliphatic polyisocyanates, alicyclic polyisocyanates, and modified polyisocyanates obtained by modifying these organic polyisocyanates, from the viewpoint of weather resistance. When using a curable composition in a location not exposed to sunlight (ultraviolet rays), it is preferable to use aromatic polyisocyanates and modified polyisocyanates obtained by modifying aromatic polyisocyanates, from the viewpoint of heat resistance and cost-effectiveness.

[0022] Organic monoisocyanates may be used together with organic polyisocyanates. That is, a mixture of organic polyisocyanates and organic monoisocyanates can be used as the organic isocyanate compound described above. Organic monoisocyanates are compounds having one isocyanate group in the compound, and specifically include aliphatic monoisocyanates such as n-butyl monoisocyanate, n-hexyl monoisocyanate, n-hexadecyl monoisocyanate, and n-octadecyl monoisocyanate; and aromatic monoisocyanates such as p-isopropylphenyl monoisocyanate and p-benzyloxyphenyl monoisocyanate.

[0023] Active hydrogen-containing compounds are compounds that have one or more active hydrogen (groups) in them. Specifically, examples include high molecular weight polyols, high molecular weight polyamines, low molecular weight polyols, low molecular weight amino alcohols, low molecular weight polyamines, and high and low molecular weight monools.

[0024] Examples of high-molecular-weight polyols include polyester polyols, polycarbonate polyols, polyoxyalkylene polyols, poly(meth)acrylic polyols, hydrocarbon polyols, animal and plant-derived polyols, and their copolyols. Here, "(meth)acrylic" means "acrylic and / or methacrylic." Also, "high-molecular-weight" means "compounds with a number-average molecular weight of 1,000 or more," and "low-molecular-weight" means "compounds with a number-average molecular weight of less than 1,000."

[0025] The number-average molecular weight of the polymer polyol is preferably 1,000 to 30,000, more preferably 1,000 to 20,000, and even more preferably 1,000 to 10,000.

[0026] Polyester polyols can be obtained by the reaction of one or more carboxylic acids with one or more low molecular weight polyols. Examples of carboxylic acids include polycarboxylic acids such as succinic acid, adipic acid, sebacic acid, azelaic acid, terephthalic acid, isophthalic acid, orthophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, hexahydroorthophthalic acid, naphthalenedicarboxylic acid, and trimellitic acid, as well as anhydrides of these polycarboxylic acids and alkyl esters such as methyl esters and ethyl esters of these polycarboxylic acids. Examples of low molecular weight polyols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, diethylene glycol, dipropylene glycol, 1,4-cyclohexanedimethanol, ethylene oxide or propylene oxide adducts of bisphenol A, trimethylolpropane, glycerin, and pentaerythritol.

[0027] Furthermore, in addition to the carboxylic acids and low molecular weight polyols mentioned above, polyester amide polyols obtained by reacting one or more low molecular weight polyamines such as butylenediamine, hexamethylenediamine, xylylenediamine, and isophoronediamine, or low molecular weight amino alcohols such as monoethanolamine and diethanolamine, are also mentioned. Moreover, lactone-based polyester polyols obtained by ring-opening polymerization of cyclic ester (lactone) monomers such as ε-caprolactone and γ-valerolactone using low molecular weight polyols, low molecular weight polyamines, and low molecular weight amino alcohols as initiators are also mentioned.

[0028] Examples of polycarbonate polyols include reaction products obtained by the dehydrochlorination reaction of low molecular weight polyols used in the synthesis of polyester polyols mentioned above with phosgene, or by the transesterification reaction of the low molecular weight polyols mentioned above with diethylene carbonate, dimethyl carbonate, diethyl carbonate, or diphenyl carbonate.

[0029] Examples of polyoxyalkylene polyols include low molecular weight polyols, low molecular weight polyamines, and low molecular weight amino alcohols used in the synthesis of the polyester polyols mentioned above, as well as low molecular weight polyhydric alcohols such as sorbitol, mannitol, sucrose, and glucose; and low molecular weight polyhydric phenols such as bisphenol A and bisphenol F. These are obtained by ring-opening addition polymerization or copolymerization of one or more cyclic ether compounds such as ethylene oxide, propylene oxide, butylene oxide, and tetrahydrofuran, resulting in polyoxyethylene polyols, polyoxypropylene polyols, polyoxybutylene polyols, polyoxytetramethylene polyols, and poly-(oxyethylene)-(oxypropylene)-random or block copolymer polyols.

[0030] Furthermore, examples include polyester ether polyols and polycarbonate ether polyols initiated from the aforementioned polyester polyols or polycarbonate polyols. Alternatively, these various ether polyols may be reacted with organic isocyanate compounds in an excess of hydroxyl groups relative to the isocyanate groups to produce polyols with hydroxyl groups at the molecular ends. The number of alcoholic hydroxyl groups in polyoxyalkylene polyols is, on average, two or more per molecule, preferably two to four, and particularly preferably two to three.

[0031] Suitable catalysts for synthesizing polyoxyalkylene polyols include alkali metal compound catalysts such as sodium-based catalysts and potassium-based catalysts, cationic polymerization catalysts, complex metal cyanide complex catalysts such as zinc hexacyanocobaltate glyme complexes and diglyme complexes, and phosphazene compound catalysts. Of these catalysts, alkali metal compound catalysts and complex metal cyanide complex catalysts are preferred. Furthermore, polyoxyalkylene polyols synthesized using complex metal cyanide complex catalysts are preferred because they have a low degree of total unsaturation and low viscosity.

[0032] Furthermore, if necessary, polyoxyalkylene monools, such as polyoxypropylene monools obtained by ring-opening addition polymerization of cyclic ether compounds such as propylene oxide, can be used as an initiator for modifying the urethane prepolymer, using low molecular weight monoalcohols such as methyl alcohol, ethyl alcohol, and propyl alcohol. The number average molecular weight of the polyoxyalkylene monool is preferably between 1,000 and 10,000.

[0033] The term "system" in the above-mentioned polyoxyalkylene-based polyol or polyoxyalkylene-based monool means that if 50% or more, preferably 80% or more, more preferably 90% or more, and particularly preferably 95% or more of the portion excluding hydroxyl groups in 1 mole of the molecule is composed of polyoxyalkylene, the remaining portion may be modified with esters, urethanes, polycarbonates, polyamides, poly(meth)acrylates, polyolefins, etc. In the present invention, "(meth)acrylate" means "acrylate and / or methacrylate".

[0034] Poly(meth)acrylic polyols are obtained by copolymerizing a hydroxyl group-containing (meth)acrylic monomer with another ethylenically unsaturated compound by a radical polymerization method such as batch polymerization or continuous polymerization, with or without a solvent. Poly(meth)acrylic polyols obtained by continuous bulk copolymerization at a high temperature, preferably 150 to 350°C, more preferably 210 to 250°C, in the absence of a solvent are preferred because the molecular weight distribution of the reaction product is narrow and the viscosity is low. In this copolymerization reaction, it is preferable that the hydroxyl group-containing (meth)acrylic monomer is used such that the average number of hydroxyl groups per molecule of poly(meth)acrylic polyol is 1.2 to 4. The glass transition temperature (Tg) of the poly(meth)acrylic polyol is preferably 50°C or lower, more preferably 0°C or lower, even more preferably -70°C to -20°C, and particularly preferably -70°C to -30°C.

[0035] Hydroxyl group-containing (meth)acrylic monomers are (meth)acrylic monomers having at least one hydroxyl group in the molecule. Specifically, examples include hydroxyalkyl (meth)acrylates such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and hydroxybutyl (meth)acrylate; mono(meth)acrylates of polyhydric alcohols such as pentaerythritol tri(meth)acrylate, glycerin mono(meth)acrylate, pentaerythritol di(meth)acrylate monostearate, dipentaerythritol penta(meth)acrylate, ditrimethylolpropane tri(meth)acrylate, and polypropylene glycol mono(meth)acrylate, or polyhydric (meth)acrylates with residual hydroxyl groups. These may be used individually or in combination of two or more. Among these hydroxyl group-containing (meth)acrylic monomers, hydroxyalkyl (meth)acrylates are preferred, and hydroxyethyl (meth)acrylate is particularly preferred, from the viewpoint of having a low viscosity of (meth)acrylic polyol and good reactivity with isocyanate groups.

[0036] Examples of ethylenically unsaturated compounds other than hydroxyl-containing (meth)acrylic monomers include hydroxyl-free (meth)acrylic monomers and ethylenically unsaturated compounds other than (meth)acrylic monomers. Examples of ethylenically active compounds other than (meth)acrylic monomers include vinyl compounds such as ethylene, propylene, isobutylene, butadiene, chloroprene, styrene, chlorostyrene, 2-methylstyrene, and divinylbenzene. Examples of (meth)acrylic monomers that do not contain hydroxyl groups include (meth)acrylic acid, as well as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, benzyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, tridecyl (meth)acrylate, ethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3 Examples of (meth)acrylic acid ester compounds include -butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, glycidyl tri(meth)acrylate, and trimethylolpropane tri(meth)acrylate. These may be used individually or in combination of two or more. Among these ethylenically unsaturated compounds other than hydroxyl group-containing (meth)acrylic monomers, monomers of (meth)acrylic acid ester compounds are preferred from the viewpoint of low viscosity of (meth)acrylic polyol, and methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate are particularly preferred. Furthermore, "(meth)acrylic acid" means "acrylic acid and / or methacrylic acid."

[0037] Examples of hydrocarbon polyols include polyolefin polyols such as polybutadiene polyols and polyisoprene polyols; polyalkylene polyols such as hydrogenated polybutadiene polyols and hydrogenated polyisoprene polyols; and halogenated polyalkylene polyols such as chlorinated polypropylene polyols and chlorinated polyethylene polyols.

[0038] Examples of plant-based polyols include castor oil-based polyols and silk fibroin.

[0039] The above-mentioned polymeric polyols may be used individually or in combination of two or more. Of these polymeric polyols, polyoxyalkylene polyols and poly(meth)acrylic polyols are preferred from the viewpoint of providing good rubber properties for the curable composition after curing.

[0040] Isocyanate group-containing urethane prepolymers can also have photoreactive unsaturated bonds introduced into them for the purpose of imparting weather resistance. Urethane prepolymers with introduced photoreactive unsaturated bonds act as curing components in the curable composition of the present invention, and also provide the cured composition with good adhesion to the adherend surface and excellent weather resistance. The above-mentioned photoreactive unsaturated bonds are unsaturated bonds that undergo chemical changes such as polymerization in a relatively short time when exposed to light. Specifically, examples include unsaturated bonds derived from vinyl groups, vinylene groups, and (meth)acryloyl groups. In the present invention, "(meth)acryloyl group" means "acryloyl group and / or methacryloyl group".

[0041] The isocyanate groups in the isocyanate group-containing urethane prepolymer with introduced photoreactive unsaturated bonds react with active hydrogen-containing compounds to undergo crosslinking and curing. Furthermore, the photoreactive unsaturated bonds in the isocyanate group-containing urethane prepolymer undergo polymerization when exposed to light, forming a weather-resistant cured film on the surface of the curable composition. This cured film is believed to impart excellent weather resistance to the curable composition. Among the photoreactive unsaturated bonds, those derived from (meth)acryloyl groups are preferred due to their high weather-resistance-imparting effect.

[0042] The following methods can be used to introduce photoreactive unsaturated bonds into an isocyanate group-containing urethane prepolymer. (i) A method of reacting an organic isocyanate compound with a high molecular weight active hydrogen-containing compound (number average molecular weight of 1,000 or more) and a low molecular weight active hydrogen-containing compound (number average molecular weight of less than 1,000) having active hydrogen and a photoreactive unsaturated bond within the molecule, under conditions of an excess of isocyanate groups relative to the total amount of active hydrogen. (ii) A method of reacting an organic isocyanate compound with an active hydrogen-containing compound (e.g., mono(meth)acrylate of polyoxyalkylene triol, alkylene oxide adduct of (meth)acrylic acid, polybutadiene polyol) which is a polymer (number average molecular weight of 1,000 or more) having active hydrogen and a photoreactive unsaturated bond in its molecule, under conditions of excess isocyanate groups relative to the total amount of active hydrogen. (iii) A method of reacting an organic isocyanate compound with a low molecular weight (number average molecular weight less than 1,000) active hydrogen-containing compound having a photoreactive unsaturated bond and an isocyanate group in the molecule (e.g., (meth)acryloyl isocyanate) and a high molecular weight (number average molecular weight 1,000 or more) active hydrogen-containing compound under conditions of excess isocyanate groups relative to the total amount of active hydrogen. Of these methods, method (i) is preferred from the viewpoint of easy availability of raw materials and high reactivity.

[0043] The reaction to introduce photoreactive unsaturated bonds into an isocyanate group-containing urethane prepolymer may be carried out by charging the raw materials all at once or by charging the raw materials sequentially. The molar ratio (isocyanate group / active hydrogen) of the isocyanate group of the organic isocyanate compound to the active hydrogen of the active hydrogen-containing compound (including compounds having active hydrogen and photoreactive unsaturated bonds) is not particularly limited as long as it is greater than 1.0, but is preferably in the range of 1.2 or more from the viewpoint of preventing the viscosity of the urethane prepolymer from increasing and reducing the workability of the curable composition, and is preferably in the range of 10 or less from the viewpoint of reducing the amount of carbon dioxide generated when the isocyanate group reacts with water and preventing foaming during curing, and is particularly preferably in the range of 1.2 to 5.0. The isocyanate group content in the isocyanate group-containing urethane prepolymer into which photoreactive unsaturated bonds have been introduced is preferably 0.3% by mass or more, from the viewpoint of preventing the viscosity of the urethane prepolymer from increasing and the workability of the curable composition from decreasing, and preferably 15% by mass or less, from the viewpoint of reducing the amount of carbon dioxide generated when the isocyanate group reacts with water and preventing foaming during curing, and particularly preferably in the range of 0.5% by mass or more and 5% by mass or less.

[0044] The concentration of the photoreactive unsaturated bond in the isocyanate group-containing urethane prepolymer into which the photoreactive unsaturated bond has been introduced is preferably 0.01 mmol / g or more, more preferably 0.03 mmol / g or more and 1 mmol / g or less, and particularly preferably 0.05 mmol / g or more and 0.5 mmol / g or less.

[0045] The active hydrogen-containing compounds (low molecular weight and high molecular weight) having active hydrogen and photoreactive unsaturated bonds described above are compounds that contain both active hydrogen (groups) such as hydroxyl groups, amino groups, and carboxyl groups, and photoreactive unsaturated bonds such as vinyl groups, vinylene groups, and (meth)acryloyl groups. From the viewpoint of ease of reaction with the isocyanate group of an organic isocyanate compound and a high effect of imparting weather resistance, it is preferable that the active hydrogen-containing compound having active hydrogen and a photoreactive unsaturated bond contains a hydroxyl group and a (meth)acryloyl group in its molecule. Furthermore, from the viewpoint of ease of introduction into isocyanate group-containing urethane prepolymers, it is preferable that the number average molecular weight of the active hydrogen-containing compound having active hydrogen (groups) and photoreactive unsaturated bonds is less than 1,000.

[0046] Examples of active hydrogen-containing compounds having a hydroxyl group and a (meth)acryloyl group include (a) monoesters of alkylene glycols such as ethylene glycol, propylene glycol, and butylene glycol with (meth)acrylic acid, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 4-hydroxypentyl (meth)acrylate, hydroxyneopentyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, hydroxyheptyl (meth)acrylate, and hydroxyoctyl (meth)acrylate. Polyesters; (b) Polyesters such as monoesters, diesters, and triesters of trifunctional or more alkylene polyols such as glycerin, trimethylolpropane, and pentaerythritol with (meth)acrylic acid. Examples include monohydropoly(meth)acrylates such as glycerin di(meth)acrylate, trimethylolpropane di(meth)acrylate, and pentaerythritol tri(meth)acrylate; polyhydropoly(meth)acrylates such as glycerin mono(meth)acrylate, trimethylolpropane mono(meth)acrylate, and pentaerythritol mono(meth)acrylate; and polyhydropoly(meth)acrylates such as pentaerythritol di(meth)acrylate.

[0047] In addition to these, other examples include monohydroxymono(meth)acrylates, polyhydroxymono(meth)acrylates, and polyhydroxypoly(meth)acrylates, which are esters of (meth)acrylic acid with polyols obtained by adding ethylene oxide, propylene oxide, or butylene oxide to diethylene glycol, dipropylene glycol, polyoxyethylene polyol, polyoxypropylene polyol, bisphenol A or bisphenol F, and (meth)acrylic acid. Also, examples include compounds in which an alkylene oxide such as ethylene oxide, propylene oxide, or butylene oxide is added to the active hydrogen of a hydroxyalkyl(meth)acrylate such as (meth)acrylic acid or hydroxyethyl(meth)acrylate, and which have a hydroxyl group, as well as compounds that have a hydroxyl group, such as caprolactone-modified hydroxyethyl(meth)acrylate. These may be used individually or in combination of two or more. Among these active hydrogen-containing compounds having a hydroxyl group and a (meth)acryloyl group, monohydroxypoly(meth)acrylates and dihydroxypoly(meth)acrylates are preferred.

[0048] <Oxazolidine compounds> The curable composition of the present invention may optionally contain an oxazolidine compound along with an isocyanate group-containing urethane prepolymer. The oxazolidine compound is a compound having one or more, preferably 2 to 4, more preferably 2 to 3, oxazolidine rings in its molecule, which are saturated 5-membered heterocyclic rings containing oxygen and nitrogen atoms. The oxazolidine compound reacts with water, such as moisture, to hydrolyze, and the oxazolidine rings generate (regenerate) secondary amino groups and alcoholic hydroxyl groups, thereby functioning as a latent curing agent for the isocyanate group-containing urethane prepolymer. When the isocyanate groups of the urethane prepolymer react with water, such as moisture, they form urea bonds and harden. However, carbon dioxide gas is also generated at this time, and bubbles due to carbon dioxide gas may form in the cured product, causing defects such as deterioration of appearance, fracture of the cured product, and decreased adhesion. On the other hand, when a curable composition containing an isocyanate group-containing urethane prepolymer and an oxazolidine compound is reacted with water, the water and the oxazolidine compound react preferentially, and the oxazolidine ring of the oxazolidine compound generates a secondary amino group and an alcoholic hydroxyl group (active hydrogen group). The generated active hydrogen group (especially the secondary amino group) then preferentially reacts with the isocyanate group, thereby suppressing the generation of carbon dioxide due to the reaction between water and the isocyanate group, and preventing foaming during the curing of the curable composition.

[0049] Furthermore, when the organic polyisocyanate used in the production of the isocyanate group-containing urethane prepolymer is an aliphatic polyisocyanate or an alicyclic polyisocyanate, the curing of the curable composition may be slow. Therefore, by using an isocyanate group-containing urethane prepolymer and an oxazolidine compound in combination in the curable composition, the curing of the curable composition can be accelerated, and the amount of curing-accelerating catalyst used, as described later, can be reduced.

[0050] Examples of oxazolidine compounds include urethane bond-containing oxazolidine compounds, ester group-containing oxazolidine compounds, oxazolidine silyl ether compounds, and carbonate group-containing oxazolidine compounds. These oxazolidine compounds are obtained by reacting the hydroxyl group of a compound having a hydroxyl group and an oxazolidine ring with the isocyanate group of an organic polyisocyanate or the carboxyl group of an organic carboxylic acid compound. Among these oxazolidine compounds, urethane bond-containing oxazolidine compounds are preferred because they are easy to manufacture.

[0051] Specific examples of compounds having a hydroxyl group and an oxazolidine ring include N-hydroxyalkyloxazolidines obtained by a dehydration condensation reaction between the secondary amino group of an alkanolamine and the carbonyl group of a ketone compound or aldehyde compound. A method for producing such compounds having a hydroxyl group and an oxazolidine ring involves using 1 mole or more, preferably 1 mole to 1.5 moles, and more preferably 1 mole to 1.2 moles, of the carbonyl group of an aldehyde compound or ketone compound for every 1 mole of the secondary amino group of an alkanolamine, and carrying out a dehydration condensation reaction in a solvent such as toluene or xylene while heating, refluxing, and removing the by-product water. Excess aldehyde or ketone compounds can be removed by distillation.

[0052] Examples of alkanolamines include diethanolamine, dipropanolamine, and N-(2-hydroxyethyl)-N-(2-hydroxypropyl)amine. Examples of ketone compounds include acetone, diethyl ketone, isopropyl ketone, methyl ethyl ketone, methyl propyl ketone, methyl isopropyl ketone, methyl butyl ketone, methyl isobutyl ketone, methyl-tert-butyl ketone, diisobutyl ketone, cyclopentanone, and cyclohexanone. Examples of aldehyde compounds include aliphatic aldehyde compounds such as acetaldehyde, propionaldehyde, n-butyraldehyde, isobutyraldehyde, valeraldehyde, isovaleraldehyde, 2-methylbutyraldehyde, n-hexylaldehyde, 2-methylpentylaldehyde, n-octylaldehyde, and 3,5,5-trimethylhexylaldehyde; and aromatic aldehyde compounds such as benzaldehyde, methylbenzaldehyde, trimethylbenzaldehyde, ethylbenzaldehyde, isopropylbenzaldehyde, isobutylbenzaldehyde, methoxybenzaldehyde, dimethoxybenzaldehyde, and trimethoxybenzaldehyde. These can be used individually or in combination of two or more.

[0053] Of these alkanolamines, diethanolamine is preferred as the alkanolamine from the viewpoint of ease of production of compounds having a hydroxyl group and an oxazolidine ring, and excellent anti-foaming properties when the curable composition hardens. As for the ketone compound or aldehyde compound, an aldehyde compound is preferred, and as for the aldehyde compound, isobutyraldehyde, 2-methylpentylaldehyde, and benzaldehyde are preferred.

[0054] Preferred compounds having a hydroxyl group and an oxazolidine ring include 2-isopropyl-3-(2-hydroxyethyl)oxazolidine, 2-(1-methylbutyl)-3-(2-hydroxyethyl)oxazolidine, and 2-phenyl-3-(2-hydroxyethyl)oxazolidine.

[0055] A urethane-bonded oxazolidine compound can be obtained, for example, by reacting the isocyanate group of an organic polyisocyanate with the hydroxyl group of a compound having an oxazolidine ring. The reaction is carried out such that the molar ratio (isocyanate group / hydroxyl group) of the isocyanate group of the organic polyisocyanate with the hydroxyl group of the compound having an oxazolidine ring is preferably 0.9 to 1.2, and more preferably 0.95 to 1.05. A reaction catalyst or organic solvent may be used during the reaction as needed. The reaction temperature is preferably 50 to 120°C.

[0056] Organic polyisocyanates used in the production of urethane bond-containing oxazolidine compounds include compounds similar to those used in the production of urethane prepolymers described above. Of these, aromatic aliphatic polyisocyanates, aliphatic polyisocyanates, and alicyclic polyisocyanates are preferred, and xylylene diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate are more preferred.

[0057] Ester group-containing oxazolidine compounds can be obtained, for example, by reacting the above-mentioned compound having a hydroxyl group and an oxazolidine ring with a lower alkyl ester of a dicarboxylic acid or polycarboxylic acid.

[0058] Oxazolidine silyl ether compounds can be obtained, for example, by a de-alcoholization reaction of the above-mentioned compounds having a hydroxyl group and an oxazolidine ring with an alkoxysilane such as trimethoxysilane, tetramethoxysilane, triethoxysilane, dimethoxydimethylsilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, or 3-glycidoxypropyltriethoxysilane.

[0059] A carbonate group-containing oxazolidine compound can be obtained, for example, by reacting the above-mentioned compound having a hydroxyl group and an oxazolidine ring with a carbonate such as diallyl carbonate using a polyhydric alcohol such as diethylene glycol or glycerin.

[0060] These oxazolidine compounds may be used individually or in combination of two or more.

[0061] It is preferable that the oxazolidine compound does not contain functional groups or isocyanate groups with active hydrogen, such as amino groups or hydroxyl groups, that react with the isocyanate groups of the urethane prepolymer within the molecule. This prevents an increase in the viscosity of the urethane prepolymer and a decrease in the foam-preventing performance of the oxazolidine compound. However, in the production of the urethane bond-containing oxazolidine compound described above, a small amount of functional groups or isocyanate groups with active hydrogen may remain in the molecule depending on the molar ratio. If this does not affect the viscosity of the urethane prepolymer or the foam-preventing performance of the oxazolidine compound, it can be considered that the compound does not contain functional groups or isocyanate groups with active hydrogen. The term "small amount" refers to a quantity of functional groups or isocyanate groups with active hydrogen remaining in the molecule that is preferably 0.05 mmol or less, and more preferably 0.02 mmol or less, per gram of the oxazolidine compound.

[0062] Regarding the amount of oxazolidine compound blended, it is preferable that the amount of active hydrogen from the secondary amino group generated (regenerated) by hydrolysis of the oxazolidine compound is 0.1 moles or more and 1.0 moles or less, more preferably 0.3 moles or more and 1.0 moles or less, and particularly preferably 0.5 moles or more and 1.0 moles or less, per 1.0 mole of isocyanate groups of the urethane prepolymer.

[0063] <Cross-linkable (hydrolyzable) silyl group-containing resin> A crosslinkable (hydrolyzable) silyl group-containing resin is a resin having one or more crosslinkable (hydrolyzable) silyl groups in it. The crosslinkable silyl groups introduced into the resin undergo hydrolysis at room temperature with moisture such as humidity in the air, and the resulting silanol groups undergo condensation to crosslink and harden, yielding a cured product. Examples of crosslinkable silyl group-containing resins include those generally called silicone resins or modified silicone resins. Of these, modified silicone resins are preferred because they have excellent rubber properties and stain resistance after curing.

[0064] Silicone resins are resins whose main chain is an organopolysiloxane and which have crosslinkable silyl groups in their chemical structure. Specifically, examples include one-component silicone resins containing an organopolysiloxane with silanol groups at the terminals as the main component and a low molecular weight compound containing crosslinkable silyl groups as the crosslinking component, and two-component silicone resins containing an organopolysiloxane with silanol groups at the terminals as the main component and an aminooxyalkylsilane as the curing agent. Examples of low molecular weight compounds containing crosslinkable silyl groups include acyloxyalkylsilanes, aminooxyalkylsilanes, and alkoxyalkylsilanes.

[0065] Examples of modified silicone resins include the compounds disclosed in Japanese Patent Publication No. 52-73998, No. 55-9669, No. 59-122541, No. 60-6747, No. 61-233043, No. 63-6003, No. 63-112642, No. 3-79627, No. 4-283259, No. 5-287186, No. 11-80571, No. 11-116763, and No. 11-130931. Specifically, these include polymers having one or more crosslinkable silyl groups in the resin, and whose main chain is a vinyl polymer, polyoxyalkylene polymer, (meth)acrylic copolymer, aliphatic hydrogen carbohydrate polymer such as polyisoprene, polyisobutylene, and polybutanediene, and polyester polymers and polysulfide polymers. Copolymers of the above polymers and mixtures of polymers are also included. These may be used individually or in combination of two or more.

[0066] For the main chain of the modified silicone resin, polyoxyalkylene polymers, polyoxyalkylene polymers that may be (meth)acrylic modified, and (meth)acrylic copolymers are preferred in terms of the good rubber properties such as modulus and elongation of the cured composition.

[0067] Furthermore, "(meth)acrylic modification" includes blocking or pendant copolymerizing (meth)acrylic monomers into polyoxyalkylene polymers, mixing polyoxyalkylene polymers and (meth)acrylic copolymers, and polymerizing (meth)acrylic monomers in polyoxyalkylene polymers into which crosslinkable silyl groups have been introduced.

[0068] From the viewpoint of the curability of the curable composition and the physical properties after curing, it is preferable that the molecule contains an average of one or more crosslinkable silyl groups, and particularly preferable that it contains an average of one to three crosslinkable silyl groups. The crosslinkable silyl groups are preferably those represented by the following general formula (1), which are easy to crosslink and manufacture.

[0069] [ka]

[0070] In formula (1) above, R is a hydrocarbon group, preferably an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, or an aralkyl group having 7 to 20 carbon atoms, and particularly preferably a methyl group. If there are multiple Rs, they may be the same group or different groups. The reactive group represented by X is a hydrolyzable group selected from halogen atoms, hydrogen atoms, hydroxyl groups, alkoxy groups, acyloxy groups, ketoximate groups, amide groups, acid amide groups, mercapto groups, alkenyloxy groups, and aminooxy groups, and if there are multiple Xs, they may be the same group or different groups. Of these, X is preferably an alkoxy group, and particularly preferably a methoxy group or an ethoxy group. Also, a is preferably an integer of 0, 1, or 2, and particularly preferably 0 or 1.

[0071] The introduction of crosslinkable silyl groups into the main chain can be carried out, for example, by the following known methods. (iv) A method of hydrosilylation by reacting a polyoxyalkylene or vinyl polymer having a functional group such as a hydroxyl group at its terminus with an organic compound having an active group and an unsaturated group that are reactive to this functional group (e.g., allyl isocyanate), and then reacting the unsaturated group of the resulting reaction product with a hydrolyzable hydrosilane. (v) A method of reacting polyoxyalkylene or vinyl polymers having functional groups such as hydroxyl groups, epoxy groups, or isocyanate groups at their termini with a compound having a reactive functional group that is reactive to this functional group and a crosslinkable silyl group. Examples of such compounds having a reactive functional group and a crosslinkable silyl group include amino group-containing silanes, mercapto group-containing silanes, epoxy group-containing silanes, vinyl-type unsaturated group-containing silanes, chlorine atom-containing silanes, isocyanate group-containing silanes, and hydrosilanes. (vi) A method for copolymerizing a compound having polymerizable unsaturated bonds and crosslinkable silyl groups (for example, CH2=CHSi(OCH3)3 or CH2=CHCOO(CH2)2Si(OCH3)3) with an alkyl (meth)acrylate monomer. (vii) A method of copolymerizing a compound having polymerizable unsaturated bonds and functional groups (for example, hydroxyethyl (meth)acrylate or allyl (meth)acrylate) by adding it to an alkyl (meth)acrylate monomer, and then reacting the resulting copolymer with a compound having the aforementioned reactive functional group and crosslinkable silyl group (for example, a compound having an isocyanate group and a -Si(OCH3)3 group, or hydrosilanes having hydrolyzable groups such as trimethoxysilane and triethoxysilane).

[0072] The number-average molecular weight of the silicone resin and modified silicone resin is preferably 1,000 or more, and particularly preferably 6,000 to 30,000. Furthermore, silicone resins and modified silicone resins with a narrow molecular weight distribution are preferred because they result in a lower viscosity of the curable composition, and furthermore, the rubber properties after curing are low modulus and high elongation.

[0073] The content of the curable resin is preferably 10% by mass or more and 80% by mass or less in the curable composition, and particularly preferably 20% by mass or more and 70% by mass or less.

[0074] <Hydrophilic Silica> Hydrophilic silica is a compound that imparts thixotropy to the curable composition of the present invention. Examples of hydrophilic silica include natural silica obtained by finely grinding quartz or silica sand, dry silica, and synthetic silica such as wet silica. These may be used individually or in combination of two or more. Of these, synthetic silica is preferred because of its high thixotropy-imparting effect. Among synthetic silicas, dry silica is obtained by burning a silane gas such as silicon tetrachloride in an oxygen-hydrogen flame, and is also called fumed silica. Wet silica is typically precipitated silica, which precipitates silica in solution by neutralizing sodium silicate with a mineral acid, and is also called white carbon.

[0075] Hydrophilic silica is 10m 2 / g or more 500m 2 Preferably, the particles have a BET specific surface area of ​​50 m² or less, an average primary particle diameter of 1 nm to 100 nm, and a carbon content of 0.5% by mass or less, and are particularly likely to have a BET specific surface area of ​​50 m². 2 / g or more 500m 2 Excellent thixotropy can be imparted by having a particle size of 3 nm to 70 nm, a carbon content of 0.1 mass%, and a bulk density of 20 g / L to 150 g / L, and more preferably 40 g / L to 100 g / L from the viewpoint of excellent dispersibility.

[0076] From the viewpoint of imparting dispersibility and thixotropy, the amount of hydrophilic silica added is preferably 1 to 20 parts by mass, and more preferably 3 to 15 parts by mass, per 100 parts by mass of curable resin.

[0077] <Polyether-modified silicone> Polyether-modified silicone, when used in combination with hydrophilic silica, improves dispersibility during the preparation of curable compositions and enhances the thixotropy-inducing effect of the curable compositions. Furthermore, when used in combination with hydrophilic silica in curable compositions containing curable resins, surface tack (stickiness) after curing can be reduced, improving the ability to prevent contamination of the surface of the curable composition by the adhesion of dust and dirt.

[0078] In polyether-modified silicones, it is preferable that polyether groups are bonded to the terminals and / or side chains of the polysiloxane skeleton, and more preferably that polyether groups are bonded to at least the side chains of the polysiloxane skeleton. The polyether group is preferably a polyoxyalkylene group, more preferably a polyoxyethylene group, a polyoxypropylene group, or a polyoxybutylene group, with polyoxyethylene and polyoxypropylene groups being particularly preferred. These polyoxyalkylene groups may be used individually or in combination of two or more.

[0079] Examples of polyether-modified silicone structures include the following:

[0080] [ka]

[0081] In the above structure, R = hydrogen atom or C1-C4 alkyl group, m+n = 1-100, a+b = 3-60, a / b = 100 / 0-0 / 100, and preferably m+n = 20-100, a+b = 10-60, a / b = 20 / 80-50 / 50.

[0082] The number-average molecular weight of the polyether-modified silicone is preferably 2,000 to 8,000, and more preferably 3,000 to 7,000, from the viewpoint of dispersibility and thixotropy-inducing effect. Furthermore, the weight-average molecular weight of the polyether-modified silicone is more preferably 10,000 to 30,000, and particularly preferably 15,000 to 25,000, from the viewpoint of thixotropy-inducing effect and dispersibility.

[0083] The HLB value of polyether-modified silicone is preferably 1 to 15, and particularly preferably 5 to 10, from the viewpoint of dispersibility, thixotropy-inducing effect, and surface tack prevention. Specifically, the HLB value is a numerical value calculated by the following method.

[0084] [HLB Measurement Method] Dissolve 0.5 g of the sample in 5 ml of 98% by mass ethyl alcohol, and titrate with 2% by mass phenol aqueous solution while stirring at 25°C until the solution becomes turbid. The number of ml of 2% by mass phenol aqueous solution required for this titration is defined as the cloudiness number A. The HLB value is calculated using the following formula (I).

number

[0085] From the viewpoint of dispersibility, thixotropy-inducing effect, and surface tack prevention, the amount of polyether-modified silicone blended is preferably 1 to 70 parts by mass, and more preferably 2 to 50 parts by mass, per 100 parts by mass of hydrophilic silica.

[0086] <Polyurea compounds> The curable product of the present invention may further contain polyurea compounds as needed, in addition to the components described above, to the extent that it does not impair the objectives of the present invention. Polyurea compounds can be incorporated into the curable composition to improve the rubber properties of the curable composition. They also have the effect of imparting thixotropy to the curable composition, and when used in combination with hydrophilic silica, the amount of hydrophilic silica in the curable composition can be reduced, thereby improving the dispersibility and storage stability of the curable composition.

[0087] Polyurea compounds are compounds that have one or more urea bonds (-NHCONH-) within them, and examples include reaction products of organic isocyanate compounds and amine compounds.

[0088] Examples of organic isocyanate compounds include those similar to those used in the production of the urethane prepolymer described above.

[0089] Amine compounds include compounds having one or more amino groups in their molecule. Amino groups include primary amino groups and secondary amino groups. Examples of monoamines having primary amino groups include butylamine, isobutylamine, hexylamine, heptylamine, 2-ethylhexylamine, octylamine, 3-methoxypropylamine, tetradecylamine, cetylamine, stearylamine, oleylamine, trimethylcyclohexylamine, benzylamine, and aniline. Examples of diamines having a primary amino group include ethylenediamine, 1,3-diaminopropane, 1,2-diaminopropane, 1,4-diaminobutane, hexamethylenediamine, 1,7-diaminoheptane, trimethylhexamethylenediamine, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,13-diaminotridecane, 1,14-diaminotetradecane, 1,15 Examples include diaminopentadecane, 1,16-diaminohexadecane, 1,17-diaminoheptadecane, 1,18-diaminooctadecane, isophoronediamine, diaminodicyclohexylmethane, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro(5,5)undecane, xylenediamine, phenylenediamine, diaminodiphenylmethane, diaminodiethylphenylmethane, polyoxyethylenediamine, and polyoxypropylenediamine. Examples of triamines having a primary amino group include tri(methylamino)hexane. Examples of monoamines having a secondary amino group include diethylamine, dipropylamine, diisopropylamine, dibutylamine, dihexylamine, di-2-ethylhexylamine, diphenylamine, dilaurylamine, distearylamine, and methyllaurylamine. Examples of diamines having a secondary amino group include N,N'-dilaurylpropyldiamine, N,N'-distearylbutyldiamine, N-butyl-N'-laurylethyldiamine, N-butyl-N'-laurylpropyldiamine, and N-lauryl-N'-stearylbutyldiamine.Examples of polyamines having a primary amino group and a secondary amino group include diethylenetriamine, triethylenetetramine, and methylaminopropylamine. These amine compounds may be used individually or in combination of two or more. Of these, amines having a primary amino group are preferred, monoamines having a primary amino group are more preferred, aliphatic monoamines having a primary amino group are even more preferred, and aliphatic monoamines having an alkyl group with 1 to 8 carbon atoms and a primary amino group are particularly preferred.

[0090] The amount of polyurea compound blended is preferably 1 to 200 parts by mass, and more preferably 5 to 150 parts by mass, per 100 parts by mass of hydrophilic silica.

[0091] <Additives> The curable composition of the present invention may further contain various additives as needed, in addition to the components described above, to the extent that it does not impair the objective of the present invention. Additives are used to improve various properties of the curable composition, such as viscosity adjustment, curing acceleration, and adhesion, by being incorporated into the curable composition. Specifically, additives can be selected from the group consisting of curing accelerators, plasticizers, weather stabilizers, fillers, thixotropy-imparting agents (excluding hydrophilic silica and polyurea compounds), adhesion improvers, storage stability improvers (dehydrating agents), colorants, and organic solvents. These may be used individually or in combination of two or more.

[0092] Curing accelerators are used to accelerate the crosslinking and curing of curable resins by reacting with active hydrogen-containing compounds (e.g., water such as moisture). Furthermore, curing accelerators can also be used as reaction catalysts during the production of the aforementioned urethane prepolymers and urethane bond-containing oxazolidine compounds. When curing accelerators are used as reaction catalysts during the production of urethane prepolymers and urethane bond-containing oxazolidine compounds, any residual reaction catalyst in them may also act as a curing accelerator for the curable composition.

[0093] Examples of curing accelerator catalysts include metal-based catalysts and amine-based catalysts.

[0094] Examples of metal catalysts include salts of metals and organic acids, salts of organometallic and organic acids, and metal chelate compounds. Examples of salts of metals and organic acids include salts of various metals such as tin, bismuth, zirconium, zinc, and manganese with organic acids such as octic acid, neodecanoic acid, stearic acid, and naphthenic acid. Specifically, examples include tin octoate, tin naphthenate, bismuth octoate, and zirconium octoate. Examples of salts of organometallic and organic acids include dibutyltin dioctoate, dibutyltin dilaurate, dibutyltin diacetate, dibutyltin dimaleate, dibutyltin distearate, dioctyltin dilaurate, dioctyltin diversate, and reaction products of dibutyltin oxide with phthalate esters. Examples of metal chelate compounds include tin chelate compounds, zirconium chelate compounds, titanium chelate compounds, aluminum chelate compounds, bismuth chelate compounds, and iron chelate compounds. Specifically, examples include dibutyltin bis(acetylacetonate), AGC's "EXCESTAR C-501" tin chelate compound, zirconium tetrakis(acetylacetonate), titanium tetrakis(acetylacetonate), aluminum tris(acetylacetonate), aluminum tris(ethylacetoacetate), bismastris(2-ethylhexanoate), acetylacetone cobalt, acetylacetone iron, acetylacetone copper, acetylacetone magnesium, acetylacetone bismuth, acetylacetone nickel, acetylacetone zinc, and acetylacetone manganese.

[0095] Examples of amine catalysts include tertiary amines and salts of tertiary amines. Examples of tertiary amines include triethylamine, tributylamine, triethylenediamine, hexamethylenetetramine, 1,8-diazabicyclo[5,4,0]undecene-7 (DBU), and 1,4-diazabicyclo[2,2,2]octane (DABCO). Examples of salts of tertiary amines include salts of these tertiary amines and organic carboxylic acids.

[0096] These curing accelerators may be used individually or in combination of two or more types.

[0097] Among these curing-accelerating catalysts, salts of metals and organic acids, salts of organometallic compounds and organic acids, and metal chelate compounds are preferred from the viewpoint of excellent curability of the curable composition, and salts of tin and organic acids, salts of zirconium and organic acids, salts of bismuth and organic acids, salts of organotin and organic acids, salts of organobismuth and organic acids, tin chelate compounds, bismuth chelate compounds, and iron chelate compounds are particularly preferred.

[0098] The amount of curing accelerator catalyst added is preferably 0.005 parts by mass or more and 5 parts by mass or less per 100 parts by mass of curable resin, and particularly preferably 0.005 parts by mass or more and 2 parts by mass or less.

[0099] In addition to the metal-based and amine-based catalysts mentioned above, organic carboxylic acid-based catalysts, phosphate ester-based catalysts, p-toluenesulfonyl monoisocyanate, and the reaction product of p-toluenesulfonyl monoisocyanate with water can be used as curing-accelerating catalysts. The organic carboxylic acid-based catalysts, phosphate ester-based catalysts, p-toluenesulfonyl monoisocyanate, and the reaction product of p-toluenesulfonyl monoisocyanate with water are all hydrolysis-accelerating catalysts (ring-opening catalysts) that promote the hydrolysis of the oxazolidine ring of an oxazolidine compound when an oxazolidine compound is blended with an isocyanate group-containing urethane prepolymer. By promoting the hydrolysis of the oxazolidine ring, the generated secondary amino group and alcoholic hydroxyl group (active hydrogen group) react with the isocyanate group of the urethane prepolymer, thereby accelerating the curing of the curable composition.

[0100] Examples of organic carboxylic acid catalysts include aliphatic carboxylic acids such as formic acid, acetic acid, propionic acid, caproic acid, oxalic acid, succinic acid, adipic acid, 2-ethylhexanoic acid (octyl acid), octenic acid, lauric acid, oleic acid, and stearic acid; α,β-unsaturated carboxylic acids such as maleic acid and acrylic acid; aromatic carboxylic acids such as phthalic acid, benzoic acid, and salicylic acid; and alicyclic acid anhydrides such as tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, and dimethylbutenyltetrahydrophthalic anhydride.

[0101] Examples of phosphate ester catalysts include orthophosphate ester compounds and phosphite ester compounds. Examples of orthophosphate ester compounds include acidic phosphate ester compounds such as ethyl acid phosphate, butyl acid phosphate, butoxyethyl acid phosphate, 2-ethylhexyl acid phosphate, and oleyl acid phosphate. Examples of phosphite ester compounds include tryster compounds such as triethyl phosphite, triphenyl phosphite, tris(nonylphenyl) phosphite, tridecyl phosphite, diphenyl mono(2-ethylhexyl) phosphite, and diphenyl monodecyl phosphite, as well as diester compounds such as dilauryl hydrogen phosphite, dioleyl hydrogen phosphite, and diphenyl hydrogen phosphite.

[0102] The reaction product of p-toluenesulfonyl monoisocyanate and water may be obtained by pre-reacting p-toluenesulfonyl monoisocyanate and water before incorporating it into the curable composition, by adding water and reacting it while p-toluenesulfonyl monoisocyanate is being incorporated into the curable composition, or by reacting it with water present in the curable composition (such as water contained in the raw materials) during or after preparation.

[0103] The amount of hydrolysis-promoting catalyst (ring-opening catalyst) added is preferably 0.001 parts by mass or more and 5 parts by mass or less per 100 parts by mass of the oxazolidine compound.

[0104] Plasticizers are used to reduce the viscosity of curable compositions to improve workability and to adjust the rubber properties of the cured compositions. Specifically, examples include phthalate esters such as dioctyl phthalate, diisononyl phthalate, dibutyl phthalate, and butyl benzyl phthalate; and aliphatic carboxylic acid esters such as dioctyl adipate, diisodecyl succinate, dibutyl sebacate, and butyl oleate.

[0105] The amount of plasticizer added is preferably 1 part by mass or more and 100 parts by mass or less per 100 parts by mass of the curable resin, and particularly preferably 5 parts by mass or more and 90 parts by mass or less.

[0106] Weather stabilizers are used to further improve the weather resistance and heat resistance of curable compositions by preventing oxidation, photodegradation, and thermal degradation. Examples of weather stabilizers include hindered amine-based light stabilizers, hindered phenol-based antioxidants, and ultraviolet absorbers. These weather stabilizers may be used individually or in combination of two or more types.

[0107] Examples of hindered amine-based light stabilizers include bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(2,2,6,6-tetramethyl-1(octyloxy)-4-piperidyl) decandioate, and bis(1,2,2,6,6-pentamethyl-4-piperidyl)[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]butylmalonate. , methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1-[2-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]ethyl]-4-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]-2,2,6,6-tetramethyl Lupiperidine, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, dimethyl succinate·1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly[{6-(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine-2,4-diyl}{(2,2,6,6-tetramethyl-4-piperidyl)imino}hexa Examples include methylene{(2,2,6,6-tetramethyl-4-piperidyl)imino}], N,N'-bis(3-aminopropyl)ethylenediamine-2,4-bis[N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino]-6-chloro-1,3,5-triazine condensate, as well as ADEKA's "ADEKA Stab LA-63P" and "ADEKA Stab LA-68LD".

[0108] Examples of hindered phenol antioxidants include pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, N,N'-hexane-1,6-diyrbis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propioamide], 3,5-bis(1,1-dimethylethyl)-4-hydroxyC7-C9 side-chain alkyl ester of benzenepropanoate, and 2,4-dimethyl-6-(1-methylpentadecyl)phenol.

[0109] Examples of UV absorbers include benzotriazole-based UV absorbers such as 2-(3,5-di-tert-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole; triazine-based UV absorbers such as 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[(hexyl)oxy]-phenol; benzophenone-based UV absorbers such as octabenzone; and benzoate-based UV absorbers such as 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate.

[0110] Among these weather stabilizers, hindered amine-based light stabilizers and hindered phenol-based antioxidants are preferred because they have a higher effect in improving weather resistance. The amount of weather stabilizer added is preferably 0.01 parts by mass or more and 30 parts by mass or less, and more preferably 0.1 parts by mass or more and 10 parts by mass or less, per 100 parts by mass of curable resin.

[0111] Fillers are used to increase the volume of the curable composition or to reinforce the physical properties of the cured product. Specifically, examples include inorganic powder fillers such as mica, kaolin, zeolite, graphite, diatomaceous earth, white clay, clay, talc, slate powder, anhydrous silicic acid, quartz fine powder, aluminum powder, zinc powder, calcium carbonate, magnesium carbonate, alumina, calcium oxide, and magnesium oxide; inorganic fibrous fillers such as glass fibers and carbon fibers; inorganic balloon-type fillers such as glass balloons, shirasu balloons, silica balloons, and ceramic balloons; organic powder fillers such as wood powder, walnut shell powder, rice husk powder, pulp powder, cotton chips, rubber powder, fine powder of thermoplastic resins, fine powder of thermosetting resins, and powders and hollow bodies of polyethylene; organic balloon-type fillers such as polyvinylidene chloride microballoons; and flame-retardant fillers such as magnesium hydroxide and aluminum hydroxide. The primary particle size of the filler is preferably 0.01 μm or more and 1,000 μm or less.

[0112] The amount of filler added is preferably 5 parts by mass or more and 300 parts by mass or less, more preferably 10 parts by mass or more and 20 parts by mass or less, and particularly preferably 20 parts by mass or more and 150 parts by mass or less, per 100 parts by mass of the curable resin.

[0113] Thioxotropes are used to prevent sagging (slump) of curable compositions. Specifically, examples include inorganic thixotropes such as hydrophobic silica and fatty acid surface-treated calcium carbonate; and organic thixotropes such as organic bentonite and fatty acid amides. Hydrophilic silica and polyurea compounds are not included as thixotropes added as additives to optional components. These may be used individually or in combination of two or more.

[0114] Hydrophobic silica is silica that has been rendered hydrophobic by treating the surface of the above-described hydrophilic silica with organosilicon compounds such as chlorosilanes, silicone oils, and silane coupling agents that are reactive with the silanol groups of the hydrophilic silica. Any of these may be used alone, or two or more of them may be used in combination. Among these, silica treated with chlorosilanes or silicone oil on the surface is preferred, and silica treated with chlorosilanes on the surface is more preferred, and silica treated with monomethyltrichlorosilane or dimethyldichlorosilane is even more preferred.

[0115] In the case of hydrophobic silica, the BET specific surface area is preferably 10 m 2 / g or more and 500 m 2 / g or less, and the average primary particle diameter is preferably 1 nm or more and 100 nm or less, and particularly preferably 50 m 2 / g or more and 500 m 2 / g or less, and the average primary particle diameter is more preferably 3 nm or more and 70 nm or less.

[0116] The blending amount of hydrophobic silica is preferably 1 part by mass or more and 50 parts by mass or less, and more preferably 1 part by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the curable resin.

[0117] Fatty acid surface-treated calcium carbonate is calcium carbonate obtained by treating the surface of heavy calcium carbonate, light calcium carbonate, or colloidal calcium carbonate with fatty acids such as fatty acids, fatty acid alkyl esters, fatty acid metal salts, and fatty acid organic salts. Examples of the fatty acid include fatty acids having 8 to 22 carbon atoms such as 2-ethylhexanoic acid (octylic acid), oleic acid, lauric acid, myristic acid, palmitic acid, stearic acid, and behenic acid. Examples of the metal salt include sodium salt, potassium salt, calcium salt, and aluminum salt, and examples of the organic salt include ammonium salt.

[0118] Adhesion enhancers are used to further improve the adhesion of curable compositions. Specifically, these include various coupling agents such as silane-based, aluminum-based, and zircoaluminate-based agents, and their partially hydrolyzed condensates. Of these, silane-based coupling agents and their partially hydrolyzed condensates are preferred from the viewpoint of further improving adhesion.

[0119] Examples of silane coupling agents include compounds containing alkoxysilyl groups with a molecular weight of 500 or less, such as vinyltrimethoxysilane, vinylmethyldimethoxysilane, 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-glycidoxypropylmethyldiethoxysilane. Other examples of silane coupling agents include compounds that are partial hydrolysis condensates of one or more of these silane coupling agents, with a number average molecular weight of 200 to 3,000. These may be used individually or in combination of two or more.

[0120] Storage stability enhancers (dehydrating agents) are used to improve the storage stability of curable compositions. Specifically, examples include vinyltrimethoxysilane, calcium oxide, and p-toluenesulfonyl isocyanate (PTSI), which react with water present in the curable composition to act as dehydrating agents. These may be used individually or in combination of two or more.

[0121] Colorants are used to color the curable composition to a desired color and to impart design properties to the composition. Specifically, examples include inorganic colorants such as titanium dioxide, iron oxide, and carbon black, and organic colorants such as copper phthalocyanine. These may be used individually or in combination of two or more.

[0122] Organic solvents are used to adjust the viscosity of the curable composition and improve its extrudeability and workability during casting or coating. The organic solvent is not particularly limited as long as it has good compatibility with other components in the curable composition and does not react with them. Specifically, examples include carbonate solvents such as dimethyl carbonate, ketone solvents such as acetone and methyl ethyl ketone, ester solvents such as ethyl acetate and butyl acetate, aliphatic solvents such as n-hexane, alicyclic solvents such as cyclohexane, aromatic solvents such as toluene and xylene, and petroleum fraction solvents such as mineral spirits and industrial gasoline. These may be used individually or in combination of two or more.

[0123] The amount of organic solvent blended is preferably 1 part by mass or more and 100 parts by mass or less, and particularly preferably 5 parts by mass or more and 90 parts by mass or less, per 100 parts by mass of curable resin.

[0124] The curable composition of the present invention can be used as a one-component curable composition because it crosslinks and hardens upon reaction with active hydrogen-containing compounds (for example, water such as moisture). Alternatively, the above-mentioned curable resin can be used as the main component, and a curing agent can be mixed to it to create a two-component curable composition.

[0125] Methods for mixing two-component curable compositions include using a mixer such as a hand mixer, a vacuum degassing mixer, or a drum rotary mixer to uniformly mix each component.

[0126] The curable compositions of the present invention are not particularly limited and can be manufactured by known methods. Specifically, a method for manufacturing a one-component curable composition includes placing a curable resin, hydrophilic silica, polyether-modified silicone, and optionally oxazolidine compounds, polyurea compounds, and additives into a mixing (kneading) container equipped with a stirring device, such as glass, stainless steel, or iron, blocking out moisture and other water, and stirring and mixing under a nitrogen atmosphere. A method for manufacturing a two-component curable composition includes blending the above-mentioned curable resin as the main component, blending hydrophilic silica and polyether-modified silicone into the main component and / or curing agent, blending a compound reactive with the curable resin (for example, an active hydrogen-containing compound such as a hydroxyl group-containing compound) into the curing agent, and further, optionally, blending oxazolidine compounds, polyurea compounds, and additives into the main component and / or curing agent, then placing the main component and curing agent separately into mixing (kneading) containers equipped with a stirring device, blocking out moisture and other water, and stirring and mixing under a nitrogen atmosphere. The curable compositions can be manufactured in batch or continuous order.

[0127] When the curable composition of the present invention is used as a one-component curable composition, the curable resin may thicken and harden upon reaction with moisture or other water. Therefore, it is preferable to store it in a sealed container that can block moisture or other water. The container is not particularly limited as long as it can block moisture or other water, but specific examples include metal or resin cans, aluminum bags, and paper or resin cartridges. Even when used as a two-component curable composition, it is preferable to store each component of the main agent and curing agent in a sealed container that can block moisture or other water. [Examples]

[0128] Examples of the present invention are shown below, but the present invention is not limited to these examples.

[0129] [Synthesis Example 1] Synthesis of isocyanate group-containing urethane prepolymer In a reaction vessel equipped with a stirrer, thermometer, nitrogen inlet tube, and heating / cooling device, while flowing nitrogen gas, 575.7g of polyoxypropylenediol ("Exenol 3021", manufactured by AGC, number average molecular weight 3,200), 149.9g of polyoxypropylenetriol ("Actcol (registered trademark) T-4000", manufactured by Mitsui Chemicals SKC Polyurethane Co., Ltd., number average molecular weight 4,000), and 1g of organic solvent (a mixed solvent of petroleum hydrocarbons, "A Solvent", manufactured by ENEOS Corporation) were added. 86.7g was added, and while stirring, 87.1g of 4,4'-diphenylmethane diisocyanate ("Millionate MT", manufactured by Tosoh Corporation, molecular weight 250) and 0.6g of Solvent A solution containing 10% by mass zirconium octoate (manufactured by Nippon Chemical Industries, Ltd.) as a reaction catalyst were added. The reaction was then heated to 70-80°C and terminated when the isocyanate group content fell below the theoretical value (0.98% by mass), thereby synthesizing an isocyanate group-containing urethane prepolymer (solution). The number-average molecular weight of the isocyanate group-containing urethane prepolymer was 1,014. In calculating the number-average molecular weight of the isocyanate group-containing urethane prepolymer, unreacted organic isocyanate compounds were also included as part of the isocyanate group-containing urethane prepolymer.

[0130] [Synthesis Example 2] Synthesis of polyurea compounds A solution prepared by dissolving 100.0 g of 4,4'-diphenylmethane diisocyanate ("Millionate MT", manufactured by Tosoh Corporation, molecular weight 250) in 300.0 g of dioctyl phthalate was mixed with a solution prepared by dissolving 55.0 g of n-butylamine in 320.0 g of dioctyl phthalate. The mixture was reacted at room temperature to synthesize a dispersion paste of polyurea compounds. The dispersion paste of polyurea compounds contains 20% by mass of polyurea compounds and 80% by mass of dioctyl phthalate.

[0131] [Example 1] In a 0.5L cylindrical kneading container equipped with a stirrer, heating / cooling device, and nitrogen inlet tube, 100.0g of the isocyanate group-containing urethane prepolymer (solution) obtained in Synthesis Example 1 was charged while flowing nitrogen gas. While stirring, 50.4g of heavy calcium carbonate, 10.2g of titanium dioxide, and 5.8g of slaked lime, which had been pre-dried in a dryer at 100-110°C to adjust the moisture content to 0.05% by mass or less, were charged along with 33.9g of dioctyl phthalate. The mixture was then mixed for 20 minutes at a rotation speed of 200 rpm using an anchor-type stirring blade. Next, a solution was prepared by adding 0.8g of a hindered phenol antioxidant (pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], "Irganox® 1010", manufactured by BASF) to 1.7g of dimethyl carbonate, 0.3g of p-toluenesulfonyl isocyanate (PTSI), 0.7g of polyether-modified silicone ("DOWSIL SH8700 Fluid", a silicone in which part of the silicone side chains (side chains of the polysiloxane skeleton) is modified with polyoxyethylene and polyoxypropylene, number average molecular weight 5,080, HLB value 7.8, manufactured by Dow-Toray), and hydrophilic silica (dry silica, "QS-102", specific surface area 200m²). 2 6.9 g of (Tokuyama Corporation, primary particle size 12 nm, bulk density 50 g / L, carbon content 0.1 mass% or less) was added and mixed at a rotation speed of 50 rpm for 30 minutes. Then, degassing was performed under reduced pressure at 50-100 hPa, and the mixture was filled into a container and sealed to prepare a curable composition (sealant composition).

[0132] [Example 2] In Example 1, the same procedure was followed except that 1.0 g of polyether-modified silicone was used to prepare a curable composition (sealant composition).

[0133] [Example 3] In Example 1, the same procedure was followed except that 1.3 g of polyether-modified silicone was used to prepare a curable composition (sealant composition).

[0134] [Example 4] In Example 1, the same procedure was followed except that 2.0 g of polyether-modified silicone was used to prepare a curable composition (sealant composition).

[0135] [Comparative Example 1] In Example 1, the same procedure was followed except that polyether-modified silicone was not used to prepare a curable composition (sealant composition).

[0136] [Comparative Example 2] In Example 2, the same procedure was followed except that hydrophilic silica was not used to prepare a curable composition (sealant composition).

[0137] [Comparative Example 3] In Example 2, hydrophilic silica was replaced with hydrophobic silica ("DM-10", silica surface-treated with dimethyldichlorosilane, specific surface area 120 m²). 2 A curable composition (sealant composition) was prepared by performing the same procedure as above, except that 6.9 g of (15 nm primary particle size, 50 g / L bulk density, 0.9 mass% carbon content, manufactured by Tokuyama Corporation) was used.

[0138] [Example 5] In a 0.5L cylindrical kneading container equipped with a stirrer, heating / cooling device, and nitrogen inlet tube, 100.0g of the isocyanate group-containing urethane prepolymer (solution) obtained in Synthesis Example 1 was charged while flowing nitrogen gas. While stirring, 50.4g of heavy calcium carbonate, 10.2g of titanium dioxide, and 5.8g of slaked lime, each of which had been pre-dried in a dryer at 100-110°C to reduce moisture content to 0.05% by mass or less, and 31.1g of dioctyl phthalate were charged, and the mixture was mixed for 20 minutes at a rotation speed of 200 rpm using an anchor-type stirring blade. Next, a solution was prepared by adding 0.8g of a hindered phenol antioxidant (pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], "Irganox® 1010", manufactured by BASF) to 1.7g of dimethyl carbonate, 0.3g of p-toluenesulfonyl isocyanate (PTSI), 1.0g of polyether-modified silicone ("DOWSIL SH8700 Fluid", a silicone in which part of the silicone side chain (side chain of the polysiloxane skeleton) is modified with polyoxyethylene and polyoxypropylene, number average molecular weight 5,080, HLB value 7.8, manufactured by Dow-Toray), and hydrophilic silica (dry silica, "QS-102", specific surface area 200m²). 2 6.3 g of (Tokuyama Corporation, with a primary particle size of 12 nm, bulk density of 50 g / L, and carbon content of 0.1 mass% or less) and 3.5 g of the polyurea compound dispersion paste obtained in Synthesis Example 2 were added and mixed further at a rotation speed of 50 rpm for 30 minutes. Then, degassing was performed under reduced pressure at 50-100 hPa, and the mixture was filled into a container and sealed to prepare a curable composition (sealant composition).

[0139] [Example 6] In Example 5, a curable composition (sealant composition) was prepared by performing the same procedure as in Example 5, except that 25.6 g of dioctyl phthalate, 4.9 g of hydrophilic silica, and 10.4 g of polyurea compound dispersion paste were used.

[0140] [Example 7] In Example 5, a curable composition (sealant composition) was prepared by performing the same procedure as in Example 5, except that 20.0 g of dioctyl phthalate, 3.5 g of hydrophilic silica, and 17.4 g of polyurea compound dispersion paste were used.

[0141] The following performance evaluations were performed using the curable compositions (sealant compositions) of Examples 1-7 and Comparative Examples 1-3. The composition and performance evaluation of the curable compositions are shown in Tables 1 and 2. Note that the numerical values ​​for the components in each table are based on parts by mass.

[0142] <Dispersibility> [exterior] A rectangular frame measuring 50mm (length) x 50mm (width) x 10mm (depth) was created on a slate board using 10mm square backers. The curable composition was filled into this frame, and any excess was scraped off with a spatula to create a smooth surface, which served as the test specimen. The surface appearance of the curable composition was visually observed and evaluated as described below. ○: The surface of the curable composition is smooth and free of blemishes. ×: The surface of the curable composition has bumps that detract from its appearance.

[0143] <Curability> [Touch dry time] The touch-dry time of the curable composition was determined in accordance with JIS A 1439 (2022) Test Methods for Building Sealants, 5.19 Touch-Dry Time Test.

[0144] <Viscosity> [viscosity] The viscosity [Pa·s] of the curable composition was measured using an E-type viscometer (25°C, 1 rpm, 10 rpm). <Thixotropy>

[0145] [slump] The slump of the curable composition was determined in accordance with JIS A 1439 (2022) Test Method 5.1 Slump Test for Building Sealants. Stainless steel was used as the test material.

[0146] [Chixsoindex] The thixoindex (TI value) of the curable composition was calculated as the viscosity ratio of the curable composition at 1 rpm to 10 rpm (viscosity of the curable composition at 1 rpm / viscosity of the curable composition at 10 rpm).

[0147] <Surface tack prevention> [Tacking Test] A square frame measuring 50mm (length) x 50mm (width) x 10mm (depth) was created on a slate board using 10mm square backers. The curable composition was filled into this frame, and the excess was scraped off with a spatula to create a smooth surface, which served as the test specimen. The test specimen was left to stand for 28 days in an environment of 23°C and 50% RH (indoors). The tackiness [N] of the surface of the curable composition was then measured using a tackiness checker (HTC-1, manufactured by Toyo Seiki Seisakusho Co., Ltd.). The measurement temperature was 23°C, the contact was a surface indenter (model AL-R1), the contact force was 10N, and the pressing time was 3 seconds.

[0148] [Tactile evaluation] A rectangular frame measuring 50 mm (length) x 50 mm (width) x 10 mm (depth) was created on a slate board using 10 mm square backers. The curable composition was filled into this frame, and any excess was scraped off with a spatula to create a smooth surface, which served as the test specimen. After the test specimen was left to stand for 28 days in an environment of 23°C and 50% RH (indoors), the following evaluation was performed based on the feel when the surface of the curable composition was lightly pressed with a fingertip for 1 second. ○: The surface of the curable composition has no tackiness (adhesion), or has only slight tackiness (adhesion). ×: The surface of the curable composition has a tacky (sticky) feel and is viscous.

[0149] <Rubber properties> [Tensile test] A rectangular frame was created on release paper using a 3mm thick square backer, the curable composition was filled into the frame, the excess was scraped off with a spatula, the surface was smoothed, and the material was cured for 28 days in an environment of 23°C and 50% RH (indoors) to produce a cured sheet. A dumbbell-shaped No. 3 test specimen was prepared from the cured sheet based on JIS K 6251 (2010) Tensile Test Method for Vulcanized Rubber. A tensile test (tensile speed 500 mm / min) was performed on the prepared test specimen in an environment of 23°C, and the tensile stress [N / cm] at 50% elongation was measured. 2 ], tensile stress at 100% elongation [N / cm 2 The elongation at break [%] was measured.

[0150] [Table 1]

[0151] [Table 2]

[0152] The curable compositions of Examples 1-4 exhibited good visual appearance and good dispersibility. Slump tests showed a slump of 1.0 mm or less, conforming to the slump standard of 3 mm or less specified in JIS A 5758 (2022) for building sealants. Furthermore, they were found to be curable compositions with high thixoindex (TI value) of 4.0 or higher, excellent thixotropy, and excellent surface tack prevention. In addition, the dumbbell-shaped rubber properties showed high tensile stress at 50% and 100% elongation, and large elongation at fracture, indicating that they result in tough and highly elongated cured products.

[0153] The curable compositions of Examples 5-7 exhibited good visual appearance and excellent dispersibility. Slump tests showed a slump of 1.0 mm or less, conforming to the slump standard of 3 mm or less specified in JIS A 5758 (2022) for building sealants. Furthermore, they were found to be curable compositions with high thixoindex (TI value) of 4.0 or higher, excellent thixotropy, and excellent surface tack prevention. In addition, the dumbbell-shaped rubber properties showed high tensile stress at 50% and 100% elongation, and significantly greater elongation at fracture, indicating that they result in tough and highly elongated cured products.

[0154] On the other hand, the curable composition of Comparative Example 1 showed poor dispersion and surface tack prevention when stirred at 50 rpm for 30 minutes after the addition of hydrophilic silica, resulting in the formation of lumps within the composition. Furthermore, the curable composition of Comparative Example 2 had a low thixoindex (TI value) of 1.5, and in the slump test, it flowed away without retaining its shape, showing poor thixotropy. In addition, it was found to have poor surface tack prevention. Furthermore, the curable composition of Comparative Example 3 had a low thixoindex (TI value) of 2.2, and in the slump test, it flowed away without retaining its shape, showing poor thixotropy. Furthermore, it was found that the elongation at break was small in the dumbbell-shaped rubber properties. [Industrial applicability]

[0155] The curable composition of the present invention can be suitably used for building and civil engineering purposes. Furthermore, the curable composition of the present invention can be suitably used as a sealing material composition, putty material composition, waterproofing material composition, adhesive composition, or coating material composition. In particular, it can be suitably used as a sealing material composition, putty material composition, waterproofing material composition, adhesive composition, or coating material composition for vertical surfaces, inclined surfaces, and ceiling surfaces where thixotropy is required.

Claims

1. A curable composition characterized by containing a curable resin, hydrophilic silica, and polyether-modified silicone.

2. The curable composition according to claim 1, wherein the curable resin is an isocyanate group-containing resin or a crosslinkable silyl group-containing resin.

3. The aforementioned hydrophilic silica is 50 m ２ / g or more 500m ２ The curable composition according to claim 1, having a BET specific surface area of ​​0.5% by mass or less and a carbon content of 0.5% by mass or less.

4. The curable composition according to claim 1, wherein the polyether-modified silicone has polyoxyalkylene groups in at least one side chain of the polysiloxane skeleton.

5. The curable composition according to claim 4, wherein the polyoxyalkylene group is a polyoxyethylene group and / or a polyoxypropylene group.

6. The curable composition according to claim 1, wherein the number average molecular weight of the polyether-modified silicone is 2,000 or more and 8,000 or less.

7. The amount of hydrophilic silica blended is 1 part by mass or more and 20 parts by mass or less per 100 parts by mass of the curable resin, and The curable composition according to claim 1, wherein the amount of polyether-modified silicone blended is 1 part by mass or more and 70 parts by mass or less per 100 parts by mass of the hydrophilic silica.

8. The curable composition according to claim 1, further containing a polyurea compound.

9. The curable composition according to claim 1, further comprising at least one additive selected from the group consisting of a curing accelerator, a plasticizer, a weather stabilizer, a filler, a thixotropy-imparting agent (excluding hydrophilic silica and polyurea compounds), an adhesion enhancer, a storage stability enhancer (dehydrating agent), a colorant, and an organic solvent.

10. The curable composition according to any one of claims 1 to 9, wherein the curable composition is a curable composition for building or civil engineering.

11. The curable composition according to any one of claims 1 to 9, wherein the curable composition is a sealant composition, a putty composition, a waterproofing composition, an adhesive composition, or a coating composition.

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