JP2021014524A - Curable composition - Google Patents

Abstract

To provide a curable composition excellent in adhesiveness to a resin material such as polyvinyl chloride, water resistance and stringiness.SOLUTION: A curable composition contains an isocyanate group-containing urethane prepolymer that does not contain an isocyanurate ring, and an isocyanate group-containing urethane prepolymer that contains an isocyanurate ring.SELECTED DRAWING: None

Description

The present invention relates to a curable composition having excellent adhesiveness, water resistance and stringiness.

A curable composition containing an isocyanate group-containing resin or a crosslinkable silyl group-containing resin as a curing component is widely used as a sealing material, an adhesive, and a waterproof material for construction and civil engineering because it has excellent workability and adhesiveness. Has been done. In particular, a polyurethane-based curable composition containing an isocyanate group-containing resin as a curing component reacts with water such as moisture in the air and easily cures, and has adhesiveness and water resistance to building members such as concrete, wood, and resin. Due to its good properties, its usage and range of application are increasing.

When a polyurethane-based curable composition is used as an adhesive for a resin member (for example, a vinyl chloride sheet, a vinyl chloride tile, etc.), strong adhesiveness to the resin member is required as the performance of the adhesive. The applicant has proposed a method for improving the adhesiveness by using a curable composition in which an isocyanurate compound is mixed with an isocyanate group-containing urethane prepolymer in order to improve the adhesiveness (for example, Patent Document 1). ).

Performances other than the adhesiveness required for adhesives include water resistance and stringiness. However, a curable composition that simultaneously improves water resistance and stringiness while having excellent adhesiveness has not yet been proposed.

Japanese Unexamined Patent Publication No. 2003-138239

The present invention provides a curable composition having excellent adhesiveness, water resistance and stringiness to a resin member such as a vinyl chloride resin.

As a result of diligent studies to solve the above problems, the present inventors have found that a curable composition containing an isocyanate group-containing urethane prepolymer having no isocyanurate ring and an isocyanate group-containing urethane prepolymer having an isocyanurate ring is chloride. They have found that they are excellent in adhesiveness, water resistance and stringiness to resin members such as vinyl resin, and have completed the present invention.

That is, the present invention solves the above problems by providing the curable compositions shown in the following (1) to (12).
(1) A curable composition containing an isocyanate group-containing urethane prepolymer having no isocyanurate ring and an isocyanate group-containing urethane prepolymer having an isocyanurate ring.
(2) The curable composition according to (1), wherein the isocyanate group-containing urethane prepolymer having an isocyanurate ring is a reaction product of an isocyanurate-modified polyisocyanate and an active hydrogen-containing compound.
(3) The curable composition according to (1) or (2), wherein the isocyanate group-containing urethane prepolymer having an isocyanurate ring has a number average molecular weight of 600 to 6,000.
(4) The curable composition according to any one of (1) to (3), wherein the isocyanate group-containing urethane prepolymer having an isocyanurate ring has an isocyanate group content of 2 to 30% by mass. Stuff.
(5) The curable composition according to (2), wherein the isocyanurate-modified polyisocyanate is a modified polyisocyanate of an organic polyisocyanate containing an aliphatic polyisocyanate and / or an alicyclic polyisocyanate.
(6) The curable composition according to (2) or (5), wherein the isocyanurate-modified polyisocyanate is a modified polyisocyanate of an organic polyisocyanate containing hexamethylene diisocyanate and / or isophorone diisocyanate.
(7) The curable composition according to (2), wherein the active hydrogen-containing compound is an active hydrogen-containing compound containing a polyol having a number average molecular weight of 50 to 900.
(8) The blending amount of the isocyanate group-containing urethane prepolymer having an isocyanurate ring is such that 1 mol of the isocyanate group-containing urethane prepolymer having no isocyanurate ring contains an isocyanate group having an isocyanurate ring. The curable composition according to any one of (1) to (7), wherein the number of moles of isocyanate groups of the urethane prepolymer is 0.5 to 5.
(9) Further, one selected from a curing acceleration catalyst, a plasticizer, a weather resistance stabilizer, a filler, a rock denaturing agent, an adhesiveness imparting agent, a storage stability improving agent (dehydrating agent), a coloring agent, and an organic solvent. The curable composition according to any one of (1) to (8), which contains the above additives.
(10) The curable composition according to any one of (1) to (9), wherein the curable composition is a curable composition for construction or civil engineering.
(11) The curable composition according to any one of (1) to (10), wherein the curable composition is an adhesive composition.
(12) The curable composition according to any one of (1) to (11), wherein the curable composition is an adhesive composition for a vinyl chloride resin.

The curable composition of the present invention is excellent in adhesiveness, water resistance and stringiness to a resin member such as vinyl chloride resin.

The curable composition of the present invention will be described. The curable composition of the present invention is characterized by containing an isocyanate group-containing urethane prepolymer having no isocyanurate ring and an isocyanate group-containing urethane prepolymer having an isocyanurate ring. Hereinafter, each component will be described in detail.

The isocyanate group-containing urethane prepolymer having no isocyanurate ring is a urethane resin having one or more isocyanate groups in one molecule and having no isocyanurate ring. The isocyanate group of the isocyanate group-containing urethane prepolymer having no isocyanurate ring reacts with the active hydrogen-containing compound to form a urethane bond, a urea bond, or the like, and is crosslinked and cured. Further, the isocyanate group-containing urethane prepolymer having no isocyanurate ring acts as a curing component in the curable composition of the present invention, and imparts good adhesiveness to the adherend member to the cured composition.

The isocyanate group-containing urethane prepolymer having no isocyanurate ring can be produced by reacting an organic isocyanate compound with an active hydrogen-containing compound all at once or sequentially so that an isocyanate group remains in the urethane prepolymer. The molar ratio (isocyanate group / active hydrogen) of the isocyanate group of the organic isocyanate compound to the active hydrogen (group) of the active hydrogen-containing compound is such that the number of moles of the isocyanate group of the organic isocyanate compound is the active hydrogen (group) of the active hydrogen-containing compound. As long as it is larger than the number of moles, it is not particularly limited, but 1.2 to 10 is preferable, and 1.2 to 5 is more preferable.

The isocyanate group content of the isocyanate group-containing urethane prepolymer having no isocyanurate ring is preferably 0.3 to 10% by mass, and particularly preferably 0.5 to 5% by mass.

The number average molecular weight of the isocyanate group-containing urethane prepolymer having no isocyanurate ring is preferably 1,500 or more, more preferably 1,500 to 20,000, further preferably 1,500 to 15,000, and 1,500. ~ 10,000 is particularly preferable. The number average molecular weight in the present specification is a polystyrene-equivalent value measured by gel permeation chromatography (GPC). If the number average molecular weight is too small to be measured by gel permeation chromatography, the number average molecular weight herein is the value measured by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-mass spectrometry (LC-MS). is there.

As a method for producing an isocyanate group-containing urethane prepolymer having no isocyanurate ring, a conventionally known method can be used. Specifically, for example, an organic isocyanate compound and an active hydrogen-containing compound are charged in a reaction vessel made of glass or stainless steel, a reaction catalyst or an organic solvent is used as necessary, and the reaction is carried out while stirring at 50 to 120 ° C. There is a way to make it. At this time, since the urethane prepolymer thickens when the isocyanate group reacts with water such as moisture, it is preferable to replace the inside of the container with nitrogen gas in advance or to carry out the reaction under a nitrogen gas stream.

Specific examples of the reaction catalyst include metal catalysts and amine catalysts.

Examples of the metal-based catalyst include a salt of a metal and an organic acid, a salt of an organic metal and an organic acid, and a metal chelate compound. Examples of the salt of the metal and the organic acid include salts of various metals such as tin, zirconium, zinc and manganese and organic acids such as octyl acid, neodecanoic acid, stearic acid and naphthenic acid. Specific examples thereof include tin octylate, tin naphthenate, and zirconium octylate. Salts of organic metals and organic acids include dibutyltin dioctate, dibutyltin dilaurate, dibutyltin diacetate, dibutyltin dimaleate, dibutyltin distearate, dioctyltin dilaurate, dioctyltin diversate, dibutyltin oxide and phthalates. Things etc. can be mentioned. Examples of the metal chelate compound include dibutyltin bis (acetylacetonet), EXCESTAR C-501 manufactured by AGC Co., Ltd., which is a tin-based chelate compound, zirconium tetrakis (acetylacetonet), titanium tetrakis (acetylacetoneate), and aluminum tris (acetyl). Acetylacetone), aluminum tris (ethylacetone acetate), acetylacetone cobalt, acetylacetone iron, acetylacetone copper, acetylacetone magnesium, acetylacetone nickel, acetylacetone zinc, acetylacetone manganese and the like.

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

When a reaction catalyst is used in the production of an isocyanate group-containing urethane prepolymer having no isocyanurate ring, the reaction catalyst remaining in the urethane prepolymer may act as a curing acceleration catalyst for the curable composition.

Specific examples of the organic solvent 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, and aliphatic solvents such as n-hexane. Examples thereof include alicyclic solvents such as cyclohexane, aromatic solvents such as toluene and xylene, and organic solvents such as petroleum distillate solvents such as mineral spirit and industrial gasoline.

Specific examples of the organic isocyanate compound include organic polyisocyanates. The organic polyisocyanate is a compound having two or more isocyanate groups in one molecule. Specifically, for example, toluene polyisocyanate such as 2,4-toluene diisocyanate and 2,6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate and the like. Diphenylmethane polyisocyanate, 1,2-phenylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 2,4,6-trimethylphenyl-1,3-diisocyanate, 2,4,6-triisopropylphenyl Phenylene polyisocyanate such as -1,3-diisocyanate, 1,4-naphthalene diisocyanate, naphthalene polyisocyanate such as 1,5-naphthalene diisocyanate, chlorophenylene-2,4-diisocyanate, 4,4'-diphenylether diisocyanate, 3, Examples thereof include aromatic polyisocyanides such as 3'-dimethyldiphenylmethane-4,4'-diisocyanate and 3,3'-dimethoxydiphenyl-4,4'-diisocyanate. In addition, 1,6-hexamethylene diisocyanate, 1,5-pentamethylene diisocyanate, 1,4-tetramethylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 2,4,4-trimethyl- Aromatic polyisocyanates such as 1,6-hexamethylene diisocyanate, decamethylene diisocyanate, and lysine diisocyanate, aromatic aliphatic polyisocyanates such as o-xylylene diisocyanate, m-xylylene diisocyanate, and p-xylylene diisocyanate, 1,4- Examples thereof include alicyclic polyisocyanates such as cyclohexamethylene diisocyanate, isophorone diisocyanate, hydrogenated toluene diisocyanate, hydrogenated xylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Further, polypeptide isocyanates such as polymethylene polyphenyl polyisocyanate and crude toluene diisocyanate can be mentioned. Furthermore, modified isocyanates obtained by modifying these organic polyisocyanates and having one or more uretdione bond, allophanate bond, burette bond, uretonimine bond, carbodiimide bond, urethane bond or urea bond can be mentioned. All of these can be used alone or in combination of two or more.

Of these, aromatic polyisocyanates, aromatic aliphatic polyisocyanates, and modified isocyanates obtained by modifying these organic polyisocyanates are preferable because the curable composition is excellent in adhesiveness, curability, and mechanical properties.

Moreover, organic monoisocyanate can be used together with organic polyisocyanate. That is, the above-mentioned mixture of organic polyisocyanate and organic monoisocyanate can be used as the organic isocyanate compound. The organic monoisocyanate is a compound having one isocyanate group in one molecule, and specifically, for example, n-butyl monoisocyanate, n-hexyl monoisocyanate, n-hexadecyl monoisocyanate, n-octadecyl monoisocyanate. Examples thereof include isocyanate, p-isopropylphenylmonoisocyanate, and p-benzyloxyphenylmonoisocyanate.

An active hydrogen-containing compound is a compound having one or more active hydrogens (groups). Specific examples thereof include high molecular weight polyols, high molecular weight monools, and low molecular weight polyols. These can be used alone or in combination of two or more. In the present specification, "polymer" means a number average molecular weight of 1,000 or more, and "small molecule" means a number average molecular weight of less than 1,000.

Specific examples of the polymer polyol include polyoxyalkylene-based polyols, polyester polyols, polycarbonate polyols, hydrocarbon-based polyols, poly (meth) acrylate-based polyols, and animal and plant-based polyols. Of these, polyoxyalkylene-based polyols and poly (meth) acrylate-based polyols are preferable. As used herein, the term "(meth) acrylate" means "acrylate and / or methacrylate".

The number average molecular weight of the polymer polyol is preferably 1,000 to 30,000, more preferably 1,000 to 20,000, and particularly preferably 1,000 to 10,000.

Examples of the polyoxyalkylene-based polyol include polyoxyalkylene-based triols and polyoxyalkylene-based diols.

In the present specification, the "system" of the polyoxyalkylene-based polyol is composed of 50% by mass or more, further 80% by mass or more, particularly 90% by mass or more of the portion of the molecule excluding the hydroxyl group. If so, it means that the remaining portion may be modified with ester, urethane, polycarbonate, polyamide, poly (meth) acrylate, polyolefin or the like. It is particularly preferable that 95% by mass or more of the molecule excluding the hydroxyl group is composed of polyoxyalkylene.

The polyoxyalkylene-based triol and the polyoxyalkylene-based diol can be produced, for example, by ring-opening addition polymerization of alkylene oxide as an initiator using a polymerization catalyst. The total degree of unsaturation of the polyoxyalkylene triol and the polyoxyalkylene diol is preferably 0.1 meq / g or less, more preferably 0.07 meq / g or less, and particularly preferably 0.04 meq / g or less.

Examples of the polymerization catalyst include alkali metal compound catalysts such as sodium catalysts and potassium catalysts, cationic polymerization catalysts, composite metal cyanation complex catalysts such as zinc hexacyanocobaltate glyme complex and diglyme complex, and phosphazene compound catalysts. .. Of these, alkali metal compound catalysts and composite metal cyanide complex catalysts are preferable.

As the initiator, a compound having 2 to 3 active hydrogens (groups) (hydroxyl groups or amino groups capable of reacting with an alkylene oxide) in one molecule is used. A small amount of a compound having 4 active hydrogens (groups) in one molecule can be used in combination with these.

As an initiator for producing a polyoxyalkylene-based triol, a compound having 3 active hydrogens (groups) in one molecule is mainly used. Specific examples of the compound in which the number of active hydrogens in one molecule is 3 include trihydric alcohols such as glycerin and trimethylolpropane.

As an initiator for producing a polyoxyalkylene-based diol, a compound having 2 active hydrogens (groups) in one molecule is mainly used. Specific examples of the compound in which the number of active hydrogens in one molecule is 2 include 2 such as ethylene glycol, propylene glycol, 1,4-butanediol, diethylene glycol, dipropylene glycol, bisphenol A, and bisphenol F. Propylene alcohol can be mentioned.

Specific examples of the alkylene oxide include ethylene oxide, propylene oxide, 1,2-epoxybutane, 2,3-epoxybutane and the like. Of these, the combined use of propylene oxide, ethylene oxide, propylene oxide and ethylene oxide is preferable, and the combined use of propylene oxide, propylene oxide and ethylene oxide is particularly preferable.

As the polyoxyalkylene triol, polyoxypropylene triol, polyoxyethylene triol, and polyoxyethylene propylene triol are preferable, and polyoxypropylene triol and polyoxyethylene propylene triol are more preferable. The number average molecular weight of the polyoxyalkylene triol is preferably 1,000 to 30,000, more preferably 1,000 to 20,000, and particularly preferably 1,000 to 10,000.

In addition, in this specification, "oxyethylene propylene" includes an oxyethylene group (-CH ₂ CH ₂ O-) and an oxypropylene group (-CH (CH ₃ ) CH ₂ O-) in a molecule.

As the polyoxyalkylene diol, polyoxypropylene diol, polyoxyethylene diol, and polyoxyethylene propylene diol are preferable, and polyoxypropylene diol and polyoxyethylene propylene diol are more preferable. The number average molecular weight of the polyoxyalkylene diol is preferably 1,000 to 30,000, more preferably 1,000 to 20,000, and particularly preferably 1,000 to 10,000.

Examples of polyester polyols include succinic acid, adipic acid, sebacic acid, azelaic acid, terephthalic acid, isophthalic acid, orthophthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid, hexahydroorthophthalic acid, naphthalenedicarboxylic acid, and trimellits. Polycarboxylic acids such as acids, one or more of these anhydrides or carboxylic acids including alkyl esters such as methyl esters and ethyl esters, and 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, Low molecular weight polyols such as 8-octanediol, 1,9-nonanediol, diethylene glycol, dipropylene glycol, 1,4-cyclohexanedimethanol, ethylene oxide or propylene oxide adducts of bisphenol A, trimethylpropane, glycerin or pentaerythritol. Examples thereof include polyester polyols obtained by reacting with one or more of the following species. In addition to these carboxylic acids and low molecular weight polyols, low molecular weight polyamines such as butyrene diamine, hexamethylenediamine, xylylenediamine and isophoronediamine, and one of low molecular weight amino alcohols such as monoethanolamine and diethanolamine. A polyesteramide polyol obtained by reacting with the above can also be mentioned.

Examples of the polycarbonate polyol include a dehydrochloration reaction between the low molecular weight polyols used in the synthesis of the polyester polyol described above and phosgene, or an ester of the low molecular weight polyols described above with diethylene carbonate, dimethyl carbonate, diethyl carbonate, and diphenyl carbonate. Examples are those obtained by the exchange reaction.

As the poly (meth) acrylate-based polyol, for example, a (meth) acrylate monomer containing a hydroxyl group such as hydroxyethyl (meth) acrylate and another (meth) acrylic acid alkyl ester monomer may be used as required. Examples thereof include those obtained by copolymerizing using a radical polymerization initiator.

Examples of the hydrocarbon-based polyol include polyolefin polyols such as polybutadiene polyols and polyisoprene polyols; polyalkylene polyols such as hydrogenated polybutadiene polyols and hydrogenated polyisoprene polyols; and halogenated poly such as chlorinated polypropylene polyols and chlorinated polyethylene polyols. Examples thereof include alkylene polyols.

Examples of animal and plant-based polyols include castor oil-based polyols and silk fibroin.

Any of the above-mentioned polymer polyols can be used alone or in combination of two or more.

Examples of the polymer monool include polyoxyalkylene monools.

The number average molecular weight of the polymer monool is preferably 1,000 to 30,000, more preferably 1,000 to 20,000, and particularly preferably 1,000 to 10,000.

In the present specification, the "system" of the polyoxyalkylene-based monool is composed of 50% by mass or more, further 80% by mass or more, particularly 90% by mass or more of the portion of the molecule excluding the hydroxyl group. If so, it means that the remaining portion may be modified with ester, urethane, polycarbonate, polyamide, poly (meth) acrylate, polyolefin or the like. It is particularly preferable that 95% by mass or more of the molecule excluding the hydroxyl group is composed of polyoxyalkylene.

The polyoxyalkylene-based monool can be obtained, for example, by ring-opening addition polymerization of an alkylene oxide as an initiator in the presence of a polymerization catalyst. The total degree of unsaturation of the polyoxyalkylene monool is preferably 0.1 meq / g or less, more preferably 0.07 meq / g or less, and particularly preferably 0.04 meq / g or less.

Examples of the polymerization catalyst include alkali metal compound catalysts such as sodium catalysts and potassium catalysts, cationic polymerization catalysts, composite metal cyanation complex catalysts such as zinc hexacyanocobaltate glyme complex and diglyme complex, and phosphazene compound catalysts. .. Of these, alkali metal compound catalysts and composite metal cyanide complex catalysts are preferable.

As an initiator for producing a polyoxyalkylene-based monool, a compound having one active hydrogen (group) in one molecule is mainly used. Specific examples of the compound in which the number of active hydrogens (groups) in one molecule is 1 include, for example, methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, tert-butyl alcohol and the like. Hyvalent alcohols; monohydric phenols such as phenol and nonylphenol; secondary amines such as dimethylamine and diethylamine can be mentioned.

Specific examples of the alkylene oxide include ethylene oxide, propylene oxide, 1,2-epoxybutane, 2,3-epoxybutane and the like. Of these, the combined use of propylene oxide, ethylene oxide, propylene oxide and ethylene oxide is preferable, and the combined use of propylene oxide, propylene oxide and ethylene oxide is particularly preferable.

As the polyoxyalkylene-based monool, polyoxypropylene monool, polyoxyethylene monool, and polyoxyethylene propylene monool are preferable, and polyoxypropylene monool and polyoxyethylene propylene monool are further preferable.

Examples of the low molecular weight polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-. Pentandiol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, diethylene glycol, dipropylene glycol, 1,4-cyclo Examples thereof include hexanedimethanol, trimethylolpropane, glycerin, pentaerythritol, bisphenol skeleton-containing polyether polyol, polyester polyol, polycarbonate polyol, polyoxyalkylene-based polyol, hydrocarbon-based polyol, animal and plant-based polyol, and copolyol thereof. .. All of these low molecular weight polyols can be used alone or in combination of two or more. Of these, 1,4-butanediol, neopentyl glycol, and a bisphenol skeleton-containing polyether polyol are preferable because the curable composition is excellent in adhesiveness and mechanical properties.

The number average molecular weight of the low molecular weight polyol is not particularly limited as long as it is less than 1,000, but is preferably 50 to 900, and particularly preferably 50 to 600.

The isocyanate group-containing urethane prepolymer having an isocyanurate ring is a urethane resin having one or more isocyanate groups and one or more isocyanurate rings in one molecule. The isocyanate group-containing urethane prepolymer having an isocyanurate ring reacts with an active hydrogen-containing compound in the same manner as the isocyanate group-containing urethane prepolymer having no isocyanurate ring to form urethane bonds, urea bonds and the like, and cross-link and cure. Further, the isocyanate group-containing urethane prepolymer having an isocyanurate ring improves the adhesiveness and imparts excellent water resistance and good stringiness when the adherend members are bonded together.

The isocyanate group-containing urethane prepolymer having an isocyanurate ring is prepared by reacting an organic isocyanate compound containing an isocyanurate-modified polyisocyanate with an active hydrogen-containing compound all at once or sequentially so that an isocyanate group remains in the urethane prepolymer. Can be manufactured. The molar ratio (isocyanate group / active hydrogen) of the isocyanate group of the organic isocyanate compound to the active hydrogen (group) of the active hydrogen-containing compound is such that the number of moles of the isocyanate group of the organic isocyanate compound is the active hydrogen (group) of the active hydrogen-containing compound. As long as it is larger than the number of moles, it is not particularly limited, but 2 to 15 is preferable, and 2 to 10 is more preferable.

The isocyanate group content of the isocyanate group-containing urethane prepolymer having an isocyanurate ring is preferably 2 to 30% by mass, particularly preferably 5 to 25% by mass.

The number average molecular weight of the isocyanate group-containing urethane prepolymer having an isocyanurate ring is preferably 600 to 6,000, more preferably 800 to 4,000, and particularly preferably 1,000 to 2,000.

As a method for producing an isocyanate group-containing urethane prepolymer having an isocyanurate ring, a conventionally known method can be used. Specifically, for example, an isocyanurate-modified polyisocyanate and an active hydrogen-containing compound are charged in a reaction vessel made of glass or stainless steel, and if necessary, a reaction catalyst or an organic solvent is used and stirred at 50 to 120 ° C. However, there is a method of reacting. At this time, since the urethane prepolymer thickens when the isocyanate group reacts with water such as moisture, it is preferable to replace the inside of the container with nitrogen gas in advance or to carry out the reaction under a nitrogen gas stream.

Examples of the reaction catalyst include the same reaction catalysts as those used for producing the isocyanate group-containing urethane prepolymer having no isocyanurate ring. Further, as the organic solvent, for example, the same organic solvent as the organic solvent that can be used for producing the isocyanate group-containing urethane prepolymer having no isocyanurate ring can be mentioned.

When a reaction catalyst is used in the production of the isocyanate group-containing urethane prepolymer having an isocyanurate ring, the reaction catalyst remaining in the urethane prepolymer may act as a curing acceleration catalyst for the curable composition.

The isocyanurate-modified polyisocyanate will be described. The isocyanurate-modified polyisocyanate is a compound having two or more isocyanate groups and one or more isocyanurate rings in one molecule.

The isocyanurate-modified polyisocyanate can be obtained by subjecting an organic polyisocyanate to an isocyanurate-forming reaction using an isocyanurate-forming catalyst. As a method for producing the isocyanurate-modified polyisocyanate, a conventionally known method can be used. Specifically, for example, an organic polyisocyanate and an isocyanurate-forming catalyst are charged in a reaction vessel made of glass or stainless steel, an organic solvent is used as necessary, and an isocyanurate-forming reaction is carried out while stirring at 30 to 90 ° C. There is a way to make it. An acidic compound such as sulfuric acid or phosphoric acid can be used to terminate the isocyanurate-forming reaction. Further, after the completion of the isocyanurate-forming reaction treatment, the unreacted organic polyisocyanate monomer can be removed by a method such as thin film distillation.

Examples of the organic polyisocyanate for producing an isocyanurate-modified polyisocyanate include the same organic polyisocyanates that can be used for producing an isocyanate group-containing urethane prepolymer having no isocyanurate ring. Any of these organic polyisocyanates can be used alone or in combination of two or more. Of these, organic polyisocyanates containing aliphatic polyisocyanates and / or alicyclic polyisocyanates are preferable, and hexamethylene diisocyanate and / or isophorone diisocyanate are particularly preferable.

Examples of the organic isocyanate compound other than the isocyanurate-modified polyisocyanate include the same organic polyisocyanate and organic monoisocyanate that can be used in producing the above-mentioned isocyanate group-containing urethane prepolymer having no isocyanurate ring. ..

Examples of the active hydrogen-containing compound used in producing an isocyanate group-containing urethane prepolymer having an isocyanurate ring include a low-molecular-weight polyol and a mixture of a low-molecular-weight polyol and a low-molecular-weight monool.

Examples of the low molecular weight polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-. Pentandiol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, diethylene glycol, dipropylene glycol, 1,4-cyclo Examples thereof include hexanedimethanol, trimethylolpropane, glycerin, pentaerythritol, bisphenol skeleton-containing polyether polyol, polyester polyol, polycarbonate polyol, polyoxyalkylene-based polyol, hydrocarbon-based polyol, animal and plant-based polyol, and copolyols thereof. .. All of these low molecular weight polyols can be used alone or in combination of two or more. Of these, neopentyl glycol, glycerin, and 3-methyl-1,5-pentanediol are preferable because the isocyanate group-containing urethane prepolymer having an isocyanurate ring is easily dissolved in an organic solvent.

The number average molecular weight of the low molecular weight polyol is not particularly limited as long as it is less than 1,000, but is preferably 50 to 900, and particularly preferably 50 to 600.

Examples of low-molecular-weight monools include linear or branched aliphatic monools having 1 to 18 carbon atoms such as methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, and decanol. Be done. All of these low molecular weight monools can be used alone or in combination of two or more.

The blending amount of the isocyanate group-containing urethane prepolymer having an isocyanurate ring is 1 mol of the isocyanate group of the isocyanate group-containing urethane prepolymer having no isocyanurate ring, and the isocyanate group of the isocyanate group-containing urethane prepolymer having an isocyanurate ring. The number of moles of the above is preferably 0.5 to 5, and more preferably 1 to 3.

The curable composition of the present invention may contain various additives in addition to the above-mentioned components, if necessary, as long as the object of the present invention is not impaired. Additives are added to the curable composition and used to improve various performances such as viscosity adjustment, curing acceleration, and adhesiveness of the curable composition. Specific examples thereof include curing acceleration catalysts, plasticizers, weather-resistant stabilizers, fillers, rock denaturing agents, adhesiveness improving agents, storage stability improving agents (dehydrating agents), colorants, organic solvents and the like. Can be done. All of these can be used alone or in combination of two or more.

The curing acceleration catalyst is used to promote cross-linking and curing of the isocyanate groups of the isocyanate group-containing urethane prepolymer having no isocyanurate ring and the isocyanate group-containing urethane prepolymer having an isocyanurate ring by reacting with water such as moisture. use. Further, the curing acceleration catalyst is a curing agent (for example, a compound having a hydroxyl group, an amino group, or a thiol group) and an isocyanate of a urethane prepolymer when the curing composition of the present invention is used as a two-component reaction curing composition. Used to accelerate the reaction with the group.

Specific examples of the curing acceleration catalyst include the same catalysts as the reaction catalysts that can be used for producing the above-mentioned isocyanate group-containing urethane prepolymer having no isocyanurate ring.

The curing acceleration catalyst can be used alone or in combination of two or more.

The amount of the curing acceleration catalyst compounded is 0.005 to 5 parts by mass with respect to 100 parts by mass of the total amount of the isocyanate group-containing urethane prepolymer having no isocyanurate ring and the isocyanate group-containing urethane prepolymer having an isocyanurate ring. Preferably, 0.005 to 2 parts by mass is particularly preferable.

The plasticizer is used for the purpose of lowering the viscosity of the curable composition to improve workability and adjusting the physical characteristics of the rubber after curing of the curable composition. Specifically, for example, phthalates such as dioctyl phthalate, diisononyl phthalate, dibutyl phthalate, and butyl benzyl phthalate; aliphatic carboxylics such as dioctyl adipate, diisodecyl succinate, dibutyl sevacinate, and butyl oleate. Low molecular weight plasticizers such as acid esters; polyoxyalkylene triols, polyoxyalkylene diols, and polyoxyalkylene monools similar to those used in the production of the above-mentioned urethane prepolymers are urethaneized, etherified or A high molecular weight plasticizer having an esterified number average molecular weight of 1,000 or more; a high molecular weight plasticizer having a number average molecular weight of 1,000 or more that does not react with isocyanate groups such as polystyrenes such as poly-α-methylstyrene and polystyrene. Can be mentioned. All of these can be used alone or in combination of two or more.

The blending amount of the plasticizer is preferably 1 to 200 parts by mass, preferably 2 to 50 parts by mass, based on 100 parts by mass of the isocyanate group-containing urethane prepolymer having no isocyanurate ring and the isocyanate group-containing urethane prepolymer having an isocyanurate ring. Parts are more preferred.

The weather-resistant stabilizer is used for the purpose of preventing oxidation, photodegradation, and thermal deterioration of the curable composition to further improve weather resistance and heat resistance. Examples of the weather resistance stabilizer include a hindered amine-based light stabilizer, a hindered phenol-based antioxidant, and an ultraviolet absorber. All of these can be used alone or in combination of two or more.

Examples of the hindered amine light stabilizer include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate and bis decanoate (2,2,6,6-tetramethyl-1 (octyloxy)). -4-piperidyl) ester, bis (1,2,2,6,6-pentamethyl-4-piperidyl) [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] butylmalo Nate, 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 Low molecular weight compounds with a molecular weight of less than 1,000, such as 6,6-tetramethylpiperidine, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine; dimethyl 1- (2-hydroxyethyl) succinate- 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} hexamethylene {(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 -In addition to the piperidine condensate, high molecular weight compounds having a molecular weight of 1,000 or more, such as Adecastab LA-63P and LA-68LD manufactured by ADEKA Co., Ltd., can be mentioned.

Examples of the hindered phenolic antioxidant include pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] and octadecyl-3- (3,5-di-tert). -Butyl-4-hydroxyphenyl) propionate, N, N'-hexane-1,6-diylbis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propioamide], benzenepropanoic acid 3,5 Examples thereof include −bis (1,1-dimethylethyl) -4-hydroxy C7-C9 side chain alkyl ester and 2,4-dimethyl-6- (1-methylpentadecyl) phenol.

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

Of these, hindered amine-based photostabilizers and hindered phenol-based antioxidants are preferable because they are highly effective in improving weather resistance. The amount of the weather-resistant stabilizer is 0.01 to 10 parts by mass with respect to 100 parts by mass of the total amount of the isocyanate group-containing urethane prepolymer having no isocyanurate ring and the isocyanate group-containing urethane prepolymer having an isocyanurate ring. It is preferable, and 0.1 to 5 parts by mass is more preferable.

The filler is used for the purpose of increasing the amount of the curable composition and reinforcing the physical properties of the cured product of the curable composition. Examples of the filler include an inorganic filler and an organic filler. Inorganic fillers include heavy calcium carbonate, light calcium carbonate, colloidal calcium carbonate, mica, kaolin, zeolite, graphite, diatomaceous earth, clay, clay, talc, silicic anhydride, quartz, aluminum powder, zinc powder, hydroxide. Inorganic powder fillers such as calcium, magnesium carbonate and alumina; examples thereof include inorganic fibrous fillers such as glass fibers and carbon fibers. Examples of the organic filler include organic powder fillers such as wood flour, walnut flour, rice husk flour, pulp flour, rubber powder, and thermoplastic or thermosetting resin powder. Further, examples of the filler include flame-retardant fillers such as magnesium hydroxide and aluminum hydroxide. All of these can be used alone or in combination of two or more.

The amount of the filler compounded is preferably 1 to 500 parts by mass with respect to 100 parts by mass of the total amount of the isocyanate group-containing urethane prepolymer having no isocyanurate ring and the isocyanate group-containing urethane prepolymer having an isocyanurate ring. ~ 300 parts by mass is more preferable, and 10 to 200 parts by mass is particularly preferable.

The rocking denaturing agent imparts rocking denaturation to the curable composition, and has the purpose of maintaining the coating shape when the curable composition is applied with a bead coating, a comb-mesh iron, or the like, or the curable composition is applied to a vertical surface or a vertical surface. It is used for the purpose of preventing sagging and slump when used on an inclined surface. Examples of the shaking denaturing agent include an inorganic shaking denaturing agent and an organic shaking denaturing agent. Examples of the inorganic rock denaturing agent include surface-treated calcium carbonate and fine powdered silica. Examples of the organic shaking denaturing agent include urea compounds, organic bentonite, fatty acid amide and the like. All of these can be used alone or in combination of two or more.

Surface-treated calcium carbonate is obtained by treating the surface of heavy calcium carbonate, light calcium carbonate, and 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 a carbonic acid number of 10 to 25 such as 2-ethylhexanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, and behenic acid. Examples of the metal salt include sodium salt, potassium salt, calcium salt, aluminum salt, and organic salt include ammonium salt.

Examples of the fine powder silica include hydrophilic silica and hydrophobic silica. All of these can be used alone or in combination of two or more.

Examples of the hydrophilic silica include natural silica obtained by finely pulverizing quartz, silica sand and the like, and synthetic silica such as dry silica and wet silica. Dry silica is obtained by burning a silane gas such as silicon tetrachloride in an oxyhydrogen flame, and is sometimes referred to as fumed silica. In addition, wet silica includes precipitation-type silica in which silica is precipitated in a solution by neutralizing sodium silicate with a mineral acid, and is sometimes referred to as white carbon.

Examples of the hydrophobic silica include those which have been made hydrophobic by surface-treating the hydrophilic silica with an organosilicon compound having reactivity with the hydrophilic silica.

The blending amount of the rock modification-imparting agent is preferably 10 to 50 parts by mass with respect to 100 parts by mass of the total amount of the isocyanate group-containing urethane prepolymer having no isocyanurate ring and the isocyanate group-containing urethane prepolymer having an isocyanurate ring. ..

The adhesiveness improver is used for the purpose of improving the adhesiveness of the curable composition. Specific examples thereof include various coupling agents such as silane-based, aluminum-based, and zirco-aluminate-based, and partially hydrolyzed condensates thereof. Of these, the silane coupling agent and its partially hydrolyzed condensate are preferable because they have excellent adhesiveness.

Examples of the silane coupling agent include vinyl silane coupling agents such as vinyl trimethoxysilane and vinyl triethoxysilane, 2- (3,4-epylcyclohexyl) ethyltrimethoxysilane, and 3-glycidoxypropylmethyldimethoxysilane. , 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane and other epoxysilane coupling agents, p-styryltrimethoxysilane and other styrylsilane cups Ring agent, methacryl coupling agent such as 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxy Acrylic silane coupling agents such as propyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyl Trimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) Aminosilane coupling agents such as -2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride, ureidosilane coupling agents such as 3-ureidopropyltrialkoxysilane, isocyanatesilane cups such as 3-isocyanoxidetriethoxysilane Examples thereof include a ring agent, an isocyanurate silane coupling agent such as tris- (trimethoxysilylpropyl) isocyanurate, and a mercaptosilane coupling agent such as 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane. In addition, examples of the silane-based coupling agent include a partially hydrolyzed condensate of the silane-based coupling agent obtained by partially hydrolyzing and condensing the alkoxy groups of these silane-based coupling agents. All of these can be used alone or in combination of two or more. Of these, epoxy silane coupling agents, aminosilane coupling agents and mercaptosilane coupling agents are preferable.

The blending amount of the adhesiveness improver is 0.1 to 10 parts by mass with respect to 100 parts by mass of the total amount of the isocyanate group-containing urethane prepolymer having no isocyanurate ring and the isocyanate group-containing urethane prepolymer having an isocyanurate ring. It is preferable, and 0.5 to 5 parts by mass is particularly preferable.

The storage stability improver (dehydrating agent) is used for the purpose of improving the storage stability of the curable composition. Specific examples thereof include vinyltrimethoxysilane, calcium oxide, and paratoluenesulfonylisocyanate, which react with water present in the curable composition to act as a dehydrating agent. All of these can be used alone or in combination of two or more.

The colorant is used for the purpose of coloring the curable composition to a desired color and imparting design to the cured product. Specific examples thereof include inorganic pigments such as carbon black, titanium oxide and iron oxide, and organic pigments such as copper phthalocyanine. All of these can be used alone or in combination of two or more.

The organic solvent is used for the purpose of improving the workability at the time of coating the curable composition by lowering the viscosity of the curable composition. The organic solvent can be used without particular limitation as long as it has good compatibility with other components in the curable composition and does not react with other components. Specifically, for example, the same as the organic solvent that can be used in the production of the isocyanate group-containing urethane prepolymer having no isocyanurate ring can be mentioned. Any of these organic solvents can be used alone or in combination of two or more.

Since the curable composition of the present invention cures by reacting with water such as moisture, it can be used as a one-component moisture-curable composition. It can also be used as a two-component reaction curable composition using the curable composition of the present invention as a main agent and an active hydrogen-containing compound such as polyamine, polyol, or polythiol as a curing agent. The curable composition of the present invention is excellent in workability without the trouble of mixing the main agent and the curing agent and without curing defects due to blending mistakes or insufficient mixing. Therefore, it is recommended to use it as a one-component moisture-curable composition. preferable.

The method for producing the curable composition of the present invention is not particularly limited, but specifically, for example, an isocyanate group-containing urethane prepolymer having no isocyanurate ring, an isocyanate group-containing urethane prepolymer having an isocyanurate ring, and the like. If necessary, add the additive to a mixing container made of glass, stainless steel, etc. with a stirrer that can block water such as moisture, stir under dry air or dry nitrogen stream, and mix until uniform. Can be done. Further, as a method for producing the curable composition, a batch method or a continuous method can be used.

Since the curable composition of the present invention is thickened and hardened by water such as humidity, it is preferable to fill it in a container capable of blocking water such as humidity, seal it, and store it. The container is not particularly limited as long as it can block water such as humidity. Specific examples thereof include metal and resin cans, aluminum and resin bags, and paper and resin cartridges.

An example of a method of use when the curable composition of the present invention is used as an adhesive composition will be described. The base to which the curable composition of the present invention is applied is, for example, a base of a building, and specifically, specifically, is preferably applied to a base of a building formed of, for example, mortar, concrete, fiber reinforced cement board, or plywood. can do. The floor material to be adhered to the base is made of resin, for example, and the shape thereof includes a tile shape, a sheet shape, a long sheet shape, and the like. As the material of the floor material, vinyl chloride resin, polyolefin resin such as polypropylene and polystyrene, polyurethane resin, synthetic rubber such as styrene-butadiene rubber, polycarbonate resin, polyphenylene oxide, polyester resin such as polybutylene terephthalate, melamine resin, etc. Examples include natural rubber and ABS resin. Of these, vinyl chloride resin is particularly suitable.

As an adhesive method using the curable composition of the present invention, for example, a method of applying the curable composition of the present invention to a base, then laying a floor material on the substrate and pressing and adhering the floor material, A method in which the curable composition of the present invention is applied, and then the curable composition-applied side of the floor material is laid on the base so as to face the base and pressed to adhere to the surface of both the base and the floor material. Examples thereof include a method in which the curable composition of the present invention is applied, and then the coated surfaces of the curable composition of the present invention are bonded to each other and pressed to adhere to each other. Examples of the method for applying the curable composition of the present invention include a method of applying using irons such as comb irons, spatula, brushes, roll coaters, etc., and beads or dots using a nozzle. A known method such as a method of applying to the coating and a method of applying by spray can be used.

Examples and the like of the present invention are shown below, but the present invention is not construed as being limited to the examples and the like.

[Synthesis Example 1] 290.0 g of ethyl acetate and polyoxy while flowing nitrogen gas through an isocyanate group-containing urethane prepolymer having no isocyanurate ring, a stirrer, a thermometer, a nitrogen seal tube, and a reaction vessel equipped with a heating / cooling device. 391.2 g of propylene triol (T-4000, hydroxyl value 42.0, manufactured by Mitsui Kagaku SKC Polyurethane Co., Ltd.), 57.1 g of polyester diol (Tesslac 2455, hydroxyl value 57.6, manufactured by Hitachi Kasei Co., Ltd.), bisphenol 107.1 g of propylene oxide adduct of A (BAP-3G, hydroxyl value 276.0, manufactured by Nippon Emulsifier Co., Ltd.) was charged, and while stirring, 4,4'-diphenylmethane diisocyanate (MDI-100, Manka Kagaku Japan Co., Ltd.) (MDI-50), 77.2 g of a mixture of 4,4'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate (MDI-50, manufactured by Manka Kagaku Japan Co., Ltd.), and 0.2 g of zirconium octylate. , Heated and reacted at 75-80 ° C. for 2 hours. When the isocyanate group content became less than the theoretical value, the reaction was terminated to synthesize an isocyanate group-containing urethane prepolymer having no isocyanurate ring. The number average molecular weight of the obtained isocyanate group-containing urethane prepolymer having no isocyanurate ring was 2,800, and the isocyanate group content was 1.35% by mass.

[Synthesis Example 2] 300.0 g of ethyl acetate and neopentyl glycol while flowing nitrogen gas through an isocyanate group-containing urethane prepolymer having an isocyanurate ring, a stirrer, a thermometer, a nitrogen seal tube, and a reaction vessel equipped with a heating / cooling device. 35.5 g of hexamethylene diisocyanate isocyanurate (HDT, NCO content 21.55%, manufactured by Vencorex) and 0.02 g of dibutyltin dilaurate are charged and heated to 75. The reaction was carried out at ~ 80 ° C. for 2 hours. The reaction was terminated when the isocyanate group content became less than the theoretical value, and an isocyanate group-containing urethane prepolymer having an isocyanurate ring was synthesized. The number average molecular weight of the obtained isocyanate group-containing urethane prepolymer having an isocyanurate ring was 1,440, and the isocyanate group content was 11.40% by mass.

[Example 1]
While flowing nitrogen gas through a stirrer, a heating / cooling device, and a mixing vessel equipped with a nitrogen-sealed tube, 100.0 g of an isocyanate group-containing urethane prepolymer having no isocyanurate ring of Synthesis Example 1 and an isocyanurate ring of Synthesis Example 2 were applied. 20.0 g of an isocyanate group-containing urethane prepolymer and 38.4 g of ethyl acetate are charged and dried in advance in a dryer at 100 to 110 ° C. with stirring to reduce the water content to 0.05% by mass or less. 103.3 g of calcium (HTO-6, manufactured by Hitachi Crushed Stone Co., Ltd.) and 26.2 g of fatty acid surface-treated calcium carbonate (CCR-S, manufactured by Shiraishi Calcium Co., Ltd.) were charged and mixed until the contents became uniform. Furthermore, 1.7 g of a silane-based coupling agent (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.), 1.3 g of fine powder silica (QS-102, manufactured by Tokuyama Corporation), and 2.6 g of paratoluenesulfonyl isocyanate. , Preparation and mixing until the contents became uniform to obtain a curable composition. The amount of the isocyanate group-containing urethane prepolymer having an isocyanurate ring in the curable composition thus obtained is isocyanate with respect to 1 mol of the isocyanate group of the isocyanate group-containing urethane prepolymer having no isocyanurate ring. The number of moles of isocyanate groups in the isocyanate group-containing urethane prepolymer having a nurate ring was 1.69 mol.

[Comparative Example 1]
In Example 1, the same operation was carried out except that the isocyanate group-containing urethane prepolymer having an isocyanurate ring of Synthesis Example 2 was not blended to obtain a curable composition.

[Comparative Example 2]
In Example 1, 6.3 g of an isocyanurate compound of hexamethylene diisocyanate (HDT, NCO content 21.55%, manufactured by Vencorex) was used instead of the isocyanate group-containing urethane prepolymer having an isocyanurate ring of Synthesis Example 2. The same operation was carried out except for blending, and a curable composition was obtained.

<Evaluation of curable composition>
The following performance evaluation test was carried out using the curable compositions of Example 1 and Comparative Examples 1 and 2. Table 1 shows the composition of the curable composition and the results of the performance evaluation test.
[Tensile adhesive strength]
A tensile adhesive strength test was conducted in accordance with JIS A 5536: 2015 "Adhesive for Floor Finishing Material" 6.3.2 Tension Adhesive Strength (Test for Polymer-based Upholstered Floor Materials). The base material is 70 mm long x 70 mm wide x 20 mm thick mortar, and the floor material is 40 mm long x 40 mm wide x 3 mm thick vinyl chloride resin tile (Royal Stone, manufactured by Toli Corporation), with an open time of 20 minutes. did. The normal curing conditions were 23 ° C. and 50% RH for 48 hours, and the curing conditions for immersion in water were 23 ° C. and 50% RH for 48 hours, and then further immersed in water at 23 ° C. for 168 hours.
[Peeling adhesive strength]
A 90-degree peel-off adhesive strength test was conducted in accordance with 63.3 peel-off adhesive strength (test for polymer-based upholstered floor materials) of JIS A 5536: 2015 “Adhesive for Floor Finishing Material”. The base material is a mortar of length 150 mm x width 70 mm x thickness 10 mm, the floor material is a vinyl chloride resin sheet (length 20 mm x width 25 mm x thickness 3 mm) (Takiron MT sheet, manufactured by Takiron CI Co., Ltd.), and the open time is 20. It was a minute. The normal curing conditions were 23 ° C. and 50% RH for 48 hours, and the curing conditions for immersion in water were 23 ° C. and 50% RH for 48 hours, and then further immersed in water at 23 ° C. for 168 hours.
[Pasteable time]
In the peeling adhesive strength test of 6.3.3 peeling adhesive strength (test for polymer-based upholstered flooring) of JIS A 5536: 2015 "Adhesive for floor finishing material", the base material was 150 mm long x 70 mm wide. × 10 mm thick mortar, floor material 20 mm long × 25 mm wide × 3 mm thick vinyl chloride resin sheet (Takistron MT sheet, manufactured by Takiron CI Co., Ltd.), and after applying the curable composition (adhesive) The open time was 30 minutes or 60 minutes, and a 90-degree peeling adhesive strength test was performed. The curing conditions were 23 ° C. and 50% RH for 48 hours.
[Threading property]
Using the same test piece as the 90 degree peeling adhesive strength test of 63.3 peeling adhesive strength (test for polymer-based upholstered flooring) of JIS A 5536: 2015 "Adhesive for floor finishing material" The base material and the floor material were attached with an open time of 30 minutes or 60 minutes after the curable composition (adhesive) was applied. After reciprocating twice with a 5 kg roller from the top of the floor material, the stringiness of the curable composition was visually observed while turning up one end of the floor material to 90 degrees and evaluated as follows.
Visual evaluation ○: The curable composition has a clear stringiness Δ: The curable composition has a slight stringiness ×: The curable composition has no stringiness

From the results in Table 1, the curable composition of the present invention (Example 1) was compared with the curable compositions of Comparative Example 1 and Comparative Example 2, and the tensile adhesive strength and 90-degree peeling were achieved in the normal state and after immersion in water. It had high adhesive strength and excellent adhesiveness and water resistance. Further, the curable composition of the present invention has a higher 90-degree peel-off adhesive strength after an open time of 30 minutes or 60 minutes than the curable compositions of Comparative Example 1 and Comparative Example 2, and has a stickable time. It was found that the workability was excellent because it could be taken for a long time. Further, the curable composition of the present invention was excellent in stringability after application.

As described above, the curable composition of the present invention is excellent in adhesiveness, water resistance, workability, and stringiness, and therefore can be suitably used for construction and civil engineering. In addition, the curable composition of the present invention can be used as an adhesive composition, a sealing material composition, and a waterproof material composition. The curable composition of the present invention can be particularly suitably used as an adhesive for a vinyl chloride resin.

Claims (12)

A curable composition comprising an isocyanate group-containing urethane prepolymer having no isocyanurate ring and an isocyanate group-containing urethane prepolymer having an isocyanurate ring. The curable composition according to claim 1, wherein the isocyanate group-containing urethane prepolymer having an isocyanurate ring is a reaction product of an isocyanurate-modified polyisocyanate and an active hydrogen-containing compound. The curable composition according to claim 1 or 2, wherein the isocyanate group-containing urethane prepolymer having an isocyanurate ring has a number average molecular weight of 600 to 6,000. The curable composition according to any one of claims 1 to 3, wherein the isocyanate group-containing urethane prepolymer having an isocyanurate ring has an isocyanate group content of 2 to 30% by mass. The curable composition according to claim 2, wherein the isocyanurate-modified polyisocyanate is a modified polyisocyanate of an organic polyisocyanate containing an aliphatic polyisocyanate and / or an alicyclic polyisocyanate. The curable composition according to claim 2 or 5, wherein the isocyanurate-modified polyisocyanate is a modified polyisocyanate of an organic polyisocyanate containing hexamethylene diisocyanate and / or isophorone diisocyanate. The curable composition according to claim 2, wherein the active hydrogen-containing compound is an active hydrogen-containing compound containing a polyol having a number average molecular weight of 50 to 900. The blending amount of the isocyanate group-containing urethane prepolymer having an isocyanurate ring is 1 mol of the isocyanate group of the isocyanate group-containing urethane prepolymer having no isocyanurate ring, and the isocyanate group-containing urethane prepolymer having the isocyanurate ring is used. The curable composition according to any one of claims 1 to 7, wherein the number of moles of the isocyanate group is 0.5 to 5. Further, one or more additions selected from a curing accelerator, a plasticizer, a weather-resistant stabilizer, a filler, a rocking denaturing agent, an adhesiveness-imparting agent, a storage stability improving agent (dehydrating agent), a coloring agent and an organic solvent. The curable composition according to any one of claims 1 to 8, wherein the curable composition contains an agent. The curable composition according to any one of claims 1 to 9, wherein the curable composition is a curable composition for construction or civil engineering. The curable composition according to any one of claims 1 to 10, wherein the curable composition is an adhesive composition. The curable composition according to any one of claims 1 to 11, wherein the curable composition is an adhesive composition for a vinyl chloride resin.