JP4328222B2 - One-component moisture-curable composition and sealant composition for further overcoating thereon - Google Patents

Description

  The present invention provides a rubber-like elastic body cured product excellent in coating film adhesion (coating film adhesion) of a paint coated by being cured by moisture in the atmosphere and the like, and has a wide application range such as a sealing material. Further, the present invention relates to a one-component moisture curable composition for performing top coating.

Conventionally, polyurethane resin has been used as a moisture curable resin component for waterproofing sealants for buildings, civil engineering, automobiles, and other curable compositions such as adhesives and paints. Widely used because of its superiority. Depending on the application of the curable composition, it may be applied or filled as an adhesive, paint or sealant on the outer wall or joints of the building and cured, and then the paint may be overcoated for the purpose of enhancing design and durability. In many cases, it is necessary that the coating film adhesion (coating film adhesion) of the top coating to the surface of the cured product is good and the coating film does not peel off over time.
When applying the top coating to the surface after curing of the curable composition containing an isocyanate group-containing urethane prepolymer, the present inventors have an organic isocyanate having an isocyanate group having a slow reaction rate with moisture as an isocyanate raw material (for example, A cured product of an isocyanate group-containing urethane prepolymer produced by using an aliphatic polyisocyanate) than an organic isocyanate having an isocyanate group having a high reaction rate with moisture (for example, an aromatic polyisocyanate). The knowledge that the coating film adhesion (coating film adhesion) of the top coating material with respect to the coating film is good was obtained. Based on this finding, if an isocyanate group-containing urethane prepolymer with a slow reaction rate with moisture is used, the resulting curable composition can be applied and filled in a relatively short period of about one week after curing and filling. When coating a paint, the coating film adhesion can be improved. As a result, the curing rate of the curable composition is slowed down. It becomes impossible to meet the request of the construction side who wants to apply paint. As a solution to this problem, the addition of a curing acceleration catalyst or the use of an isocyanate group-containing urethane prepolymer that has a high reaction rate with moisture will increase the curing rate but may result in poor adhesion of the coating film to the surface of the cured product. Further, foaming occurs in the cured product due to the generation of carbon dioxide gas during the curing, resulting in a problem that the adhesiveness and the appearance of the surface of the cured product are deteriorated.
As a result of intensive studies by the present inventors in order to solve the above problems, if a latent curing agent that reacts with moisture to generate active hydrogen groups is added to the isocyanate group-containing urethane prepolymer, the curing can be achieved even if the curing rate is increased. It has been found that when the curing period is relatively short, the coating film adhesion to the surface of the cured product is excellent, and a curable composition without foaming is obtained in the cured product.
However, even with this method, it is presumed that due to the convenience of the process, when the curing and curing period of the curable composition until the top coating is applied is longer than 2 weeks, there is no isocyanate group on the surface of the cured product. However, there remains a problem that the coating adhesion of the overcoated paint is lowered.
As a result of further investigation, the present inventors have surprisingly found that by adding an oxygen curable unsaturated compound to this, even when the curing curing period becomes long, the coating of the overcoating material on the surface of the cured product is applied. The present inventors have found that the film adhesion is extremely good and have completed the present invention.
A moisture curable polyurethane resin composition comprising a urethane prepolymer having two or more isocyanate groups at the terminal and a block amine compound that generates primary or secondary amino groups by moisture and an organically treated inorganic filler. (Refer to Patent Document 1) and a curable composition (see Patent Document 2) composed of a urethane prepolymer, a photocurable material, and an unsaturated compound capable of reacting with oxygen in the air, are disclosed. The purpose is to prevent gas swell, and the latter is for the purpose of preventing contamination and improving weather resistance.
Japanese Patent Application Laid-Open No. 07-10949 Japanese Patent Laid-Open No. 04-136070

  The present invention cures without foaming due to moisture, etc. in the atmosphere, becomes a rubber-like elastic body with excellent physical properties, and improves the adhesion and workability of the overcoated paint regardless of the curing curing period. An object of the present invention is to provide an excellent one-pack type moisture curable composition for further overcoating on a wide range of applications such as sealing materials, adhesives and paints.

In order to achieve the above object, the present invention is as shown in the following (1) to ( 6 ).
(1) an isocyanate group-containing urethane prepolymer, a latent curing agent capable of generating active hydrogen group reacts with moisture, it contains an oxygen-curable unsaturated compound, one for further top coating on this Is a liquid type moisture curable composition , wherein the isocyanate group-containing urethane prepolymer is obtained by reacting a polyoxyalkylene-based polyol and an organic isocyanate with hydroxyl groups in excess of isocyanate groups. A urethane prepolymer, wherein the organic isocyanate is 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,4,6-trimethylphenyl-1,3-diisocyanate, 2,4,6-triisopropylphenyl -1,3-diisocyanate, 3,3'-dimethyldiphenyl meta -4,4'-diisocyanate, araliphatic polyisocyanate, aliphatic polyisocyanate and alicyclic polyisocyanate, one or more selected from the group consisting of A one-component moisture curable composition for coating.
(2) The latent curing agent that reacts with moisture to produce active hydrogen groups is a compound that reacts with moisture to produce primary and / or secondary amino groups. A one-component moisture curable composition for further top coating.
(3) The one-component moisture curing for further overcoating the above (1) or (2), wherein the latent curing agent that reacts with moisture to generate an active hydrogen group is an oxazolidine compound. Sex composition.
(4) The oxygen curable unsaturated compound is one or more selected from the group consisting of drying oils, liquid (co) polymers of diene compounds, and modified products thereof, (1) A one-component moisture curable composition for further overcoating on this.
( 5 ) Further, one or two selected from the group consisting of a curing accelerating catalyst, a weather resistance stabilizer, a filler, an adhesion promoter, a thixotropic agent, a storage stability improver, a colorant and a design agent. A one-component moisture-curable composition for further overcoating on any of the above (1) to ( 4 ), comprising the above-mentioned additive.
(6) and an isocyanate group-containing urethane prepolymer, a latent curing agent capable of generating active hydrogen group reacts with moisture, it contains an oxygen-curable unsaturated compound, one for further top coating on this Isocyanate obtained by reacting a polyoxyalkylene-based polyol and an organic isocyanate with an isocyanate group-excess condition with respect to a hydroxyl group, which is a liquid moisture-curable sealant composition. A group-containing urethane prepolymer, wherein the organic isocyanate is 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,4,6-trimethylphenyl-1,3-diisocyanate, 2,4,6-triisocyanate Isopropylphenyl-1,3-diisocyanate, 3,3'-dimethyl It is further characterized in that it is one or more selected from the group consisting of phenylmethane-4,4'-diisocyanate, araliphatic polyisocyanate, aliphatic polyisocyanate and alicyclic polyisocyanate. A one-component moisture-curable sealant composition for top coating.

  For the first time according to the present invention, it is cured without foaming due to moisture in the air, etc., and becomes a rubber-like elastic body having excellent physical properties, and the coating film adhesion and workability of the overcoated paint regardless of the length of curing curing period It is possible to provide a one-pack type moisture curable composition having a wide range of applications such as a sealing material, an adhesive, and a paint, and for further overcoating thereon.

Hereinafter, the present invention will be described in detail.
The isocyanate group-containing urethane prepolymer in the present invention is one in which an isocyanate group reacts with moisture (moisture) to form a urea bond to be crosslinked and cured, and an active hydrogen compound and an organic isocyanate are combined with active hydrogen (group). ) With an excess of isocyanate groups.
Specifically, the active hydrogen compound and the organic isocyanate have a total isocyanate group / active hydrogen (group) equivalent ratio of 1.3 to 10 / 1.0, more preferably 1.5 to 5.0 / 1. It can be preferably produced by reacting simultaneously or sequentially within a range of 0.0. If the equivalent ratio is less than 1.3 / 1.0, the resulting urethane prepolymer has too few cross-linking points, and the curable composition will have reduced elongation and tensile strength after curing, resulting in rubber elastic properties and adhesion. When the equivalence ratio exceeds 10 / 1.0, the amount of carbon dioxide generated increases when reacting with moisture, which causes foaming.

Examples of the active hydrogen compound include polymeric polyols, amino alcohols, polyamines, and the like.
Examples of the polymer polyol include polyoxyalkylene polyols, polyester polyols, polyester amide polyols, polyether / ester polyols, polycarbonate polyols, poly (meth) acrylic polyols, hydrocarbon polyols, and the like. The number average molecular weight is 500 or more. belongs to.
Examples of the polyoxyalkylene-based polyol include those obtained by ring-opening addition polymerization of alkylene oxide, and those obtained by ring-opening addition polymerization of alkylene oxide in an initiator such as a compound containing two or more active hydrogens.
Examples of the initiator include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, glycerin, trimethylolpropane, pentaerythritol, diglycerin and the like. Low molecular weight polyhydric alcohols, sorbitol, sucrose, glucose, lactose, low molecular weight polyhydric alcohols such as glucose, lactose, sorbitan, low molecular weight polyphenols such as bisphenol A and bisphenol F, low molecular weight such as ethylenediamine and butylenediamine Polyamines, low molecular amino alcohols such as monoethanolamine and diethanolamine, low molecular polycarboxylic acids such as adipic acid and terephthalic acid, and at least one of these is alkylene oxide Polyoxyalkylene polyol having a low molecular weight obtained by reacting the like.
Examples of the alkylene oxide include ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran and the like, and these can be subjected to ring-opening addition polymerization alone or in combination of two or more.
Specifically, polyoxyalkylene polyols are specifically polyoxyethylene polyol, polyoxypropylene polyol, polytetramethylene ether polyol, poly (oxyethylene) -poly (oxypropylene) -random or block copolymer polyol, poly (Oxypropylene) -poly (oxybutylene) -random or block copolymer polyols and the like, and these various polyols and organic polyisocyanates such as toluene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, and isophorone diisocyanate. There may also be mentioned those having a hydroxyl group at the molecular end by reacting with an isocyanate group in excess of the hydroxyl group.
The polyoxyalkylene polyol preferably has a number average molecular weight of 500 to 100,000, more preferably 1,000 to 30,000, and particularly preferably 1,000 to 20,000 for reasons such as good workability. The average number of alcoholic hydroxyl groups per molecule is 2 or more, more preferably 2 to 4, and most preferably 2 to 3.
Further, the polyoxyalkylene-based polyol is obtained by using a catalyst such as a double metal cyanide complex, and has a total unsaturation of 0.1 meq / g or less, further 0.07 meq / g or less, particularly 0.04 meq / g. The following are preferable, and the molecular weight distribution [ratio of polystyrene-equivalent weight average molecular weight (Mw) to number average molecular weight (Mn) by gel permeation chromatography (GPC) = Mw / Mn]] is 1.6 or less, particularly 1 A narrow one of 0.0 to 1.3 is preferable.
In the present invention, the polyoxyalkylene-based polyol is composed of 50% by mass or more, more preferably 80% by mass or more, particularly preferably 90% by mass or more of the portion excluding 1 mol of hydroxyl group in the molecule. Means that the remaining part may be modified with ether, urethane, ester, polycarbonate, polyamide, polyacrylate, polyolefin, etc., but in the present invention, 95% by mass or more of the molecule excluding the hydroxyl group. Most preferred is a polyol consisting of polyoxyalkylene.
Examples of polyester polyols and polyester amide polyols include, for example, known dicarboxylic acids such as succinic acid, adipic acid, and terephthalic acid, their acid esters, acid anhydrides, and the like, and initiators for the synthesis of the above polyoxyalkylene polyols. Examples thereof include compounds obtained by a dehydration condensation reaction with a compound containing two or more active hydrogens to be used. Further examples include lactone polyester polyols obtained by cleavage polymerization of cyclic ester (ie, lactone) monomers such as ε-caprolactone.
Examples of the polyether ester polyol include compounds produced from the polyoxyalkylene polyol and the dicarboxylic acid, acid anhydride and the like.
Examples of the polycarbonate polyol include a dehydrochlorination reaction between low molecular polyhydric alcohols used in the production of the polyoxyalkylene polyol and phosgene, or transesterification with diethylene carbonate, dimethyl carbonate, diethyl carbonate, diphenyl carbonate, and the like. The compound obtained from reaction etc. is mentioned.
Examples of the poly (meth) acrylic polyol include those obtained by copolymerizing a hydroxyethyl (meth) acrylate containing a hydroxyl group with another (meth) acrylic acid alkyl ester monomer.
Examples of the hydrocarbon polyol include polybutadiene polyol, hydrogenated polybutadiene polyol, polyisoprene polyol, hydrogenated polyisoprene polyol, chlorinated polyethylene polyol, and chlorinated polypropylene polyol.
Examples of the polyol further include low molecular weight polyhydric alcohols having a number average molecular weight of less than 500, which are listed as raw materials for producing the polyoxyalkylene polyol.
Examples of the polyamine include high-molecular polyamines such as polyoxyalkylene polyamines having a number average molecular weight of 500 or more and a polyoxyalkylene polyol terminal having an amino group, such as a terminal diaminated product of polypropylene glycol.
Examples of the polyamine further include low molecular weight polyamines having a number average molecular weight of less than 500, such as ethylenediamine, hexamethylenediamine, isophoronediamine, diaminodiphenylmethane, and diethylenetriamine.
Examples of amino alcohols include monoethanolamine, diethanolamine, N-methyldiethanolamine, N-methyldipropanolamine, and N-phenyldiethanolamine.
In addition, polyamide resins, polyester resins and the like having a number average molecular weight of 500 or more, which generally contain active hydrogen groups known in the polyurethane industry, are also included.
Any of these may be used alone or in combination of two or more.
Among these, since the viscosity of the resulting isocyanate group-containing urethane prepolymer is low and the physical properties after curing are good, the viscosity of the curable composition obtained therefrom is low and the workability is good, and the rubber elasticity after curing From the viewpoint of high physical properties and adhesiveness, a polymer polyol is preferable, a polyoxyalkylene polyol is more preferable, and a polyoxypropylene polyol is particularly preferable. In addition, high molecular monoalcohols such as polyoxyalkylene monoalcohol, butyl alcohol, and octadecyl monoalcohol, and low molecular monoalcohols can be used for modifying the isocyanate group-containing urethane prepolymer.

The organic isocyanate is 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, in that the viscosity of the resulting isocyanate group-containing urethane prepolymer is low and the reaction rate between the isocyanate group of the urethane prepolymer and moisture is slow. 2,4,6-trimethylphenyl-1,3-diisocyanate, 2,4,6-triisopropylphenyl-1,3-diisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, aromatic aliphatic poly It is 1 type, or 2 or more types chosen from the group which consists of isocyanate, aliphatic polyisocyanate, and alicyclic polyisocyanate. Specific examples of the araliphatic polyisocyanate include xylylene diisocyanates such as o-xylylene diisocyanate, m-xylylene diisocyanate, and p-xylylene diisocyanate. Specific examples of the aliphatic polyisocyanate include For example, 1,6-hexamethylene diisocyanate, 1,4-tetramethylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 2,4,4-trimethyl-1,6-hexamethylene Examples of the alicyclic polyisocyanate include 1,4-cyclohexyl diisocyanate, isophorone diisocyanate, hydrogenated toluene diisocyanate. DOO, hydrogenated xylylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Of these, alicyclic polyisocyanates, particularly isophorone diisocyanate, are preferred. These can be used alone or in combination of two or more.

In the synthesis of an isocyanate group-containing urethane prepolymer, metals such as zinc, tin, lead, zirconium, bismuth, cobalt, manganese, and iron, and organic materials such as octyl acid and naphthenic acid, such as tin octylate and zirconium octylate, are used. Organic metal salts such as salts with acids, dibutyltin diacetylacetonate, zirconium tetraacetylacetonate, titanium tetraacetylacetonate, EXCESTAR C-501 (manufactured by Asahi Glass Co., Ltd.), organic metals such as dibutyltin dilaurate, dioctyltin dilaurate A known urethanization catalyst such as an organic metal compound such as a salt of an organic acid, an organic amine such as triethylenediamine, triethylamine, or tri-n-butylamine, or a salt thereof can be used. Of these, organometallic compounds are preferred, and dibutyltin dilaurate is more preferred.
Further, a known organic solvent can also be used.

  The isocyanate group content of the isocyanate group-containing urethane prepolymer is preferably 0.3 to 15.0 mass%, particularly preferably 0.5 to 5.0 mass%. When the isocyanate group content is less than 0.3% by mass, there are few crosslinking points in the prepolymer, so that sufficient adhesiveness cannot be obtained. When the isocyanate group content exceeds 15.0% by mass, the number of crosslinking points in the prepolymer increases and the rubber elasticity deteriorates, and the amount of carbon dioxide generated by the reaction with moisture increases and the cured product foams. It is not preferable in terms.

  The isocyanate group-containing urethane prepolymer is used as a one-component moisture-curing type by reaction curing with moisture (humidity) in the atmosphere at room temperature.

The latent curing agent that reacts with moisture in the present invention to generate active hydrogen groups is mixed with the isocyanate group-containing urethane prepolymer so that the isocyanate group reacts with moisture even if the reaction rate with moisture is slow. The curing rate of the curable composition is increased by using the active hydrogen group generated in this way so that the reaction rate with the isocyanate group is high and less than the equivalent ratio of the isocyanate group in the urethane prepolymer. In addition, it is surmised that the isocyanate group remaining in a small amount remains on the surface of the cured product for a relatively long time because of its slow reaction rate with moisture. It has the effect of increasing the adhesion of the paint when the paint is overcoated on the surface.
As the latent curing agent that reacts with water (hydrolyzes) to generate active hydrogen groups, specifically, a ketimine compound, an aldimine compound of a compound having a primary and / or secondary amino group, An oxazolidine compound, a silicate ester of a polyol, or any mixture thereof can be exemplified. Of these, compounds that react with moisture to produce primary and / or secondary amino groups due to the high reaction rate between the active hydrogen groups produced by reacting with moisture and the isocyanate groups of the urethane prepolymer. Specifically, a ketimine compound, an aldimine compound, an oxazolidine compound, and any mixture thereof are preferable, and an oxazolidine compound is most preferable from the viewpoint of excellent storage stability of the curable composition.
Ketimine compounds are obtained by dehydration reaction between a compound having a primary amino group and ketones, aldimine compounds are obtained by dehydration reaction between a compound having a primary amino group and aldehydes, and oxazolidine compounds are produced by monoethanolamine or diethanolamine. It can be obtained by a dehydration reaction between an amino alcohol having a primary amino group or a secondary amino group and an aldehyde.
Depending on the raw material selected, active hydrogen groups such as secondary amino groups and hydroxyl groups may remain in the molecule of the compound obtained by the above dehydration reaction. By reacting and blocking with isocyanate group of isocyanate or carboxyl group of organic carboxylic acid compound, even when coexisting with isocyanate group-containing urethane prepolymer, it does not react in the absence of moisture and has excellent storage stability. A composition can be made.
Further, as the oxazolidine compound, the hydroxyl group remaining in the molecule of the compound having an oxazolidine group obtained by the dehydration reaction of diethanolamine and isobutyraldehyde listed below is urethanated with the isocyanate group of the organic polyisocyanate listed above. The urethane group-containing oxazolidine compound obtained in this way is particularly preferred. In this case, the organic polyisocyanate to be used is preferably an aliphatic polyisocyanate, particularly hexamethylene diisocyanate, in view of the low viscosity of the resulting latent curing agent.
The silicic acid ester of a polyol is obtained by substituting the monovalent alcohol silicic acid ester (alkoxysilyl group-containing compound) with a polyol and distilling off the resulting monohydric alcohol, or the silicic acid halogen compound and the polyol. It can be obtained by dehydrohalogenation. Among these, a silicate ester of a polyol obtained by a demonohydric alcohol reaction between a polyol and an alkoxysilyl group-containing compound (a monovalent alcohol silicate ester) is preferable from the viewpoint of ease of production.

Examples of the compound having a primary and / or secondary amino group include polyamines, polyaminosilanes, amino alcohols and the like, and these can be used alone or in admixture of two or more.
Examples of the polyamine include ethylenediamine, phenylenediamine, diethylenetriamine, triethylenetetramine, methylaminopropylamine, and 3,3′-diaminodipropylamine.
Examples of the polyaminosilane include N-β-aminoethyl-γ-aminopropyltrimethoxysilane and N-β-aminoethyl-γ-aminopropylmethyldimethoxysilane.
Examples of amino alcohols include monoethanolamine and diethanolamine.

Examples of the ketones include methyl ethyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, 2-pentanone, 3-pentanone, 2-hexanone, 4-methyl-2-pentanone, 2-heptanone, 4-heptanone, diisopropyl ketone, diisobutyl. Aliphatic ketones such as ketones, aromatic ketones such as propiophenone and benzophenone, cyclic ketones such as cyclopentanone, cyclohexanone and methylcyclohexanone, β-dicarbonyl compounds such as ethyl acetoacetate, or any of these A mixture is mentioned.
Examples of the aldehydes include propionaldehyde, n-butyraldehyde, isobutyraldehyde, n-pentylaldehyde, 2-methylbutyraldehyde, n-hexylaldehyde, 2-methylpentanal, n-heptylaldehyde, and n-octylaldehyde. , Benzaldehyde, cuminaldehyde, or any mixture thereof.

  Examples of the monohydric alcohol silicate ester include tetraalkoxysilanes such as tetramethoxysilane and tetraethoxysilane, monoalkyltrialkoxysilanes such as methyltrimethoxysilane and methyltriethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxy. Alkoxysilane cups such as dialkyldialkoxysilanes such as silane, trialkylmonoalkoxysilanes such as trimethylmonomethoxysilane and trimethylmonoethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-glycidoxypropylmethyldiethoxysilane A ring agent is mentioned. These can be used alone or in admixture of two or more.

  Examples of the halogen compound of silicic acid include tetrachlorosilane, alkyltrichlorosilane, dialkyldichlorosilane, and trialkylmonochlorosilane. These can be used alone or in admixture of two or more.

  The polyol used for the silicate ester of the polyol may be a compound containing two or more hydroxyl groups in the molecule. For example, ethylene glycol, 1,4-butanediol, diethylene glycol, neopentyl glycol, 1,5 Primary grades such as pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, trimethylolpropane, pentaerythritol, polyoxyethylene glycol, polyoxytetramethylene glycol Examples thereof include polyols composed only of hydroxyl groups, propylene glycol, 1,3-butanediol, 1,4-pentanediol, glycerin, polyols composed of primary hydroxyl groups and secondary hydroxyl groups such as polyoxypropylene glycol. These can be used alone or in admixture of two or more.

  The latent curing agent that reacts with moisture to generate active hydrogen groups is preferably used in an amount of 1 to 100 parts by weight, particularly 5 to 50 parts by weight, per 100 parts by weight of the isocyanate group-containing urethane prepolymer.

The oxygen curable unsaturated compound in the present invention is a compound having in its molecule an unsaturated group that reacts and cures with oxygen, such as in the air, and is incorporated into the isocyanate group-containing urethane prepolymer to thereby provide a curable composition. It is surmised that it is due to the transition to the surface after curing of the product to form a cured coating, but in order to eliminate the adhesion of the surface of the cured product, it exhibits a long-term surface contamination prevention effect, surprisingly, After a long period of time after curing, even if a coating is applied on the surface of the cured product, it has an effect that the adhesion of the coating film becomes good. Furthermore, it also has the effect of improving the water-resistant adhesion of the coating film.
Specifically, drying oils, various modified products of drying oils, liquid polymers and copolymers of diene compounds, various modified products of these (co) polymers (maleinized modified products, boiled oil modified products, etc.) And a mixture thereof, among which dry oil and various modified products thereof, particularly dry oil are preferred.
Examples of drying oil (including semi-drying oil in a broad sense) include paulownia oil, soybean oil, linseed oil, dehydrated castor oil, coconut oil, castor oil, and the like. And various alkyd resins obtained, acrylic polymers modified with drying oil, epoxy resins, silicone resins, and the like.
Examples of (co) polymers of diene compounds include polymers of C _{4 to} C ₈ diene compounds such as 1,2-butadiene, 1,4-butadiene, 1,3-pentadiene, isoprene, chloroprene, and the like. Examples of the above-mentioned copolymers, or copolymers of these with other monomers such as styrene and acrylonitrile (SBR, NBR, etc.) and the like, and modified products of (co) polymers of diene compounds, Examples thereof include maleated products, boiled products, and epoxidized products of (co) polymers of the diene compounds.
These can be used alone or in admixture of two or more.
The oxygen-curable unsaturated compound is preferably used in an amount of 0.1 to 50 parts by weight, particularly 0.5 to 20 parts by weight, based on 100 parts by weight of the isocyanate group-containing urethane prepolymer.

  Examples of the additive in the present invention include a curing accelerating catalyst, a weathering stabilizer, a filler, an adhesiveness imparting agent, a thixotropic imparting agent, a storage stability improving agent (dehydrating agent), a colorant, and a designability imparting agent. .

The curing accelerating catalyst is a catalyst for accelerating the curing of the isocyanate group-containing urethane prepolymer. Specific examples include organometallic compounds and amines. For example, divalent organic tin compounds such as tin octylate and tin naphthenate, dibutyltin dioctoate, dibutyltin dilaurate, dibutyltin diacetate, and dibutyltin dimaleate. Tetravalent organic tin compounds such as dibutyltin distearate, dioctyltin dilaurate, dioctyltin diversate, dibutyltin oxide, dibutyltin bis (triethoxysilicate), a reaction product of dibutyltin oxide and phthalate, dibutyltin bis ( Acetylacetonate), tin-based chelate compound EXCESTAR C-501 manufactured by Asahi Glass Co., Ltd., zirconium tetrakis (acetylacetonate), titanium tetrakis (acetylacetonate), aluminum tris (acetylacetonate), aluminum Tris (ethyl acetoacetate), acetylacetone cobalt, acetylacetone iron, acetylacetone copper, acetylacetone magnesium, acetylacetone bismuth, acetylacetone nickel, acetylacetone zinc, acetylacetone manganese and other metal chelate compounds, organic acid lead salts such as lead octylate, tetra- titanates such as n-butyl titanate and tetrapropyl titanate, organic bismuth compounds such as bismuth octylate and bismuth versatate, triethylamine, tributylamine, triethylenediamine, hexamethylenetetramine, 1,8-diazabicyclo [5,4 0] Undecene-7 (DBU), 1,4-diazabicyclo [2,2,2] octane (DABCO), N-methylmorpholine, N-ethyl Tertiary amines such as Ruhorin, or a salt such as these amines and carboxylic acids. Of these, organotin compounds and metal chelate compounds are preferred because of their high reaction rate and relatively low toxicity and volatility, and dibutyltin dilaurate is particularly preferred.
The curing catalyst is preferably blended in an amount of 0 to 10 parts by mass, particularly 0.01 to 2 parts by mass with respect to 100 parts by mass of the isocyanate group-containing urethane prepolymer, from the viewpoints of curing speed and physical properties of the cured product.

  The weathering stabilizer is used to prevent oxidation, photodegradation, and thermal degradation after curing of the isocyanate group-containing urethane prepolymer and further improve not only the weather resistance but also the heat resistance. Specific examples of the weather resistance stabilizer include an antioxidant, an ultraviolet absorber, and a photocurable compound.

Specific examples of the antioxidant include hindered amine-based and hindered phenol-based antioxidants. Examples of the hindered amine-based antioxidant include bis (1,2,2,6,6-pentamethyl). -4-piperidyl) [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl] methyl] butyl malonate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) Examples include sebacate, methyl-1,2,2,6,6-pentamethyl-4-piperidyl sebacate, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine. In addition to Sanyo LS-292, trade names manufactured by Sankyo Co., Ltd., trade names Adeka Stub series LA-52, LA-57, LA-62, LA-67, LA-77, LA- 82, LA-87 and other low molecular weight hindered amine antioxidants with a molecular weight of less than 1,000, also LA-63P, LA-68LD or Ciba Specialty Chemicals' product names CHIMASSORB series 119FL, 2020FDL, 944FD, 944LD And high molecular weight hindered amine antioxidants having a molecular weight of 1,000 or more.
Examples of the hindered phenol antioxidant 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-diylbis [3- (3,5-di-tert-butyl-4-hydroxyphenylpropionamide)], benzenepropanoic acid Examples include 3,5-bis (1,1-dimethylethyl) -4-hydroxy C7-C9 side chain alkyl ester, 2,4-dimethyl-6- (1-methylpentadecyl) phenol, and the like.

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

  Examples of the photocurable compound include a compound containing one or more groups that are reactively cured by light such as an acryloyl group or a methacryloyl group in the molecule, and specifically, for example, an isocyanate group-containing urethane resin and a hydroxyl group-containing acrylate compound Polyester acrylate or polyester methacrylate such as urethane acrylate, urethane methacrylate, ester acrylate or ester methacrylate such as trimethylolpropane triacrylate or trimethylolpropane trimethacrylate, acrylate or methacrylate of polyethylene adipate polyol, etc. Polyether acrylate such as ether polyol acrylate or methacrylate, polyether methacrylate, or poly Examples thereof include vinyl cinnamates and azido resins, and monomers and oligomers having a molecular weight of 10,000 or less, and more preferably a molecular weight of 5,000 or less are preferred. Particularly, acryloyl groups and / or methacryloyl groups are averaged per molecule. The thing containing 2 or more is preferable.

  The weathering stabilizer is preferably blended in an amount of 0.01 to 30 parts by weight, particularly 0.1 to 10 parts by weight, per 100 parts by weight of the isocyanate group-containing urethane prepolymer.

  Fillers, adhesion-imparting agents, thixotropic agents, storage stability improvers (dehydrating agents), colorants, design-improving agents, etc. are reinforced, increased, improved adhesion, improved thixotropic properties, and improved storage stability. It can be used for imparting design properties such as coloring, matting of the surface of a cured product and imparting unevenness (giving a feeling of roughness).

  Examples of fillers include mica, kaolin, zeolite, graphite, diatomaceous earth, white clay, clay, talc, slate powder, anhydrous silicic acid, quartz fine powder, aluminum powder, zinc powder, and synthetic silica such as precipitated silica, heavy Inorganic fillers such as calcium carbonate, light calcium carbonate, magnesium carbonate, alumina, calcium oxide, magnesium oxide, inorganic fillers such as asbestos, glass fibers, carbon fibers, etc., or their surface Fillers treated with organic substances such as fatty acids, wood flour, walnut flour, rice husk flour, pulp powder, cotton chips, rubber powder, as well as polyamide resin, polyester resin, polyurethane resin, silicone resin, vinyl chloride resin, vinyl acetate resin, Polyolefin resins such as polyethylene and polypropylene, acrylic resins, In addition to organic fillers such as thermoplastic resin such as poxy resin, phenol resin, urea resin, melamine resin, or thermosetting resin powder, flame retardant filler such as magnesium hydroxide and aluminum hydroxide And a particle size of 0.01 to 1,000 μm is preferable.

Examples of the adhesion imparting agent include a coupling agent, an epoxy resin, a phenol resin, an alkyd resin, an alkyl titanate, and an organic polyisocyanate.
Examples of the coupling agent include various coupling agents such as silane, aluminum and zircoaluminate and / or partial hydrolysis condensates thereof. Of these, a silane coupling agent and / or a partially hydrolyzed condensate thereof is preferred because of its excellent adhesiveness.
As silane coupling agents, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, n-propyltrimethoxysilane, ethyltrimethoxysilane, diethyldiethoxysilane, n-butyltrimethoxysilane, n-hexyltriethoxysilane , N-octyltrimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, cyclohexylmethyldimethoxysilane and other hydrocarbon group-bonded alkoxysilanes, dimethyldiisopropenoxysilane, methyltriisopropenoxysilane and other hydrocarbon group-bonded Isopropenoxysilanes, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyldimethylmeth Sisilane, 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-glycidoxypropylmethyl Diisopropenoxysilane, 3-glycidoxypropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane , 3-acryloxypropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane and other functional groups such as alkoxysilanes and isopropenoxysilanes having a molecular weight of 500 or less, preferably 400 or less. Compounds having a molecular weight 200 to 3,000 are exemplified in compound and / or one or more partially hydrolyzed condensate of the silane coupling agent.

  Examples of the thixotropic agent include inorganic thixotropic agents such as colloidal silica, asbestos powder, and fatty acid-treated calcium carbonate, and organic thixotropic agents such as organic bentonite, modified polyester polyol, and fatty acid amide.

  Examples of the storage stability improver include low molecular crosslinkable silyl group-containing compounds such as vinyltrimethoxysilane, calcium oxide, and p-toluenesulfonyl isocyanate, which react with moisture present in the composition.

  Examples of the colorant include inorganic pigments such as titanium oxide and iron oxide, organic pigments such as copper phthalocyanine, and carbon black.

The design-imparting agent can be used to assist in delustering the surface of the cured product by blending it into the curable composition, or it can be used to erase the surface luster and give the appearance of natural rough rocks. In particular, examples of the material that imparts mattness include various waxes such as beeswax, carnauba wax, montan wax, paraffin wax, and stearamide. And higher aliphatic compounds.
Examples of the material that removes the gloss of the surface and imparts irregularities include granular materials and balloons, etc. The granular materials are the same as those mentioned as the filler, and large particles having a particle size of 50 μm or more are mentioned. It is done.
The balloon is a hollow substance, and the shape thereof is not only spherical, but also various shapes such as a cubic shape, a rectangular shape, and a confetti shape, and those in which the balloon is slightly broken to such an extent that the unevenness imparting effect on the curable composition is not lost. However, the spherical shape is preferred because of the good workability of the curable composition. Specifically, for example, inorganic balloons such as glass balloons, shirasu balloons, silica balloons, ceramic balloons, organic balloons such as phenol resin balloons, urea resin balloons, polystyrene balloons, polyethylene balloons, saran balloons, or inorganic compounds and organic Examples thereof include a composite balloon in which a system compound is mixed or laminated.
Also, those coated or surface-treated with these balloons can be used. For example, inorganic balloons surface-treated with the silane coupling agent, etc., organic balloons with calcium carbonate, talc, titanium oxide, etc. Examples of coatings are also included.
Of these, from the viewpoint of the effect of imparting designability, granular materials and / or balloons are preferable, and granular inorganic fillers and / or inorganic balloons are more preferable, especially coarse heavy calcium carbonate and / or ceramics. A balloon is preferred.
The particle size of the granular material and / or balloon is preferably 50 μm or more, and more preferably 100 to 1,000 μm, from the viewpoint of the effect of providing designability.

  The total amount of filler, adhesiveness imparting agent, thixotropic imparting agent, storage stability improver (dehydrating agent), colorant and designability imparting agent is 0 with respect to 100 parts by mass of the isocyanate group-containing urethane prepolymer. ˜500 parts by mass, particularly 10 to 300 parts by mass is preferable.

  In the present invention, each additive component can be used alone or in combination of two or more.

In the present invention, a plasticizer is not particularly required, but can be used within a range not impairing the object of the present invention depending on the use of the curable composition.
Examples of the plasticizer include dibutyl phthalate, diheptyl phthalate, dioctyl phthalate, di (2-ethylhexyl) phthalate, butyl benzyl phthalate, butyl phthalyl butyl glycolate, and the like, dioctyl adipate, dioctyl sebacate and the like. Low molecular weight plasticizers having a molecular weight of less than 500, such as non-aromatic dibasic acid esters, phosphate esters such as tricresyl phosphate and tributyl phosphate, and halogenated aliphatic compounds such as chlorinated paraffin, etc., and a molecular weight of 500 or more Examples of the high molecular weight type plasticizer include polyester plasticizers such as polyesters from dicarboxylic acids and glycols, etherified or esterified derivatives of polyethylene glycol and polypropylene glycol, shoes Polyethers such as sugar-based polyethers obtained by addition polymerization of ethylene oxide or propylene oxide to saccharide polyhydric alcohols such as rose, and etherification or esterification, polystyrenes such as poly-α-methylstyrene, and low viscosity Examples include (meth) acrylic acid ester copolymers. These can be used alone or in combination of two or more thereof. Among these, a high molecular weight type plasticizer having a molecular weight of 500 or more is preferable in that it does not easily migrate (bleed) to the surface of the cured product.

Since the one-component moisture-curable composition of the present invention has a low viscosity, the organic solvent may not be used or may be used in an extremely small amount, and does not release an environmental load substance, so that the safety is high.
Examples of the organic solvent include conventionally known organic solvents such as aliphatic solvents such as n-hexane, alicyclic solvents such as cyclohexane, aromatic solvents such as toluene and xylene, and the like. Anything that does not react to the above can be used. From the viewpoint of safety, the organic solvent is preferably used in the curable composition so as to be less than 10% by mass, further less than 5% by mass, and further less than 1% by mass, and most preferably 0% by mass. Do not use it.

Hereinafter, the present invention will be described in more detail with reference to examples.
Here, although the one-component moisture-curable sealing material composition has been shown as an example of the one-component moisture-curable composition, the present invention is not limited to this.

[Synthesis of isocyanate group-containing urethane prepolymer]
Synthesis example 1
In a reaction vessel equipped with a stirrer, a thermometer, a nitrogen seal tube and a heating / cooling device, 421.5 g (OH) of polyoxypropylene diol (Exenol-4020 manufactured by Asahi Glass Co., Ltd., number average molecular weight 4,000) under a nitrogen stream Equivalent: 0.211) and 421.5 g (OH equivalent: 0.253) of polyoxypropylene triol (Exenol-5030, number average molecular weight 5,000, manufactured by Asahi Glass Co., Ltd.) were charged and stirred with isophorone diisocyanate (Degussa Japan) IPDI manufactured, molecular weight 222.3) 156.7 g (NCO equivalent: 1.41) (R value (NCO equivalent / OH equivalent) = 3.1) and dibutyltin dilaurate 0.1 g were added and heated. Stir at 70-80 ° C. for 4 hours and complete the reaction when the isocyanate group content falls below the theoretical value (3.97% by mass). Was prepared isocyanate group-containing polyoxypropylene urethane prepolymer U-1.
This isocyanate group-containing polyoxypropylene-based urethane prepolymer U-1 was a viscous liquid transparent at room temperature with an isocyanate group content of 3.9% by mass measured by titration and a viscosity of 4,200 mPa · s / 25 ° C. .

[Synthesis of latent curing agent]
Synthesis example 2
After putting 435.0 g of diethanolamine into a reaction vessel equipped with a stirrer, thermometer, ester tube and heating / cooling device, 183.3 g of toluene was added. After further stirring, 328.3 g of isobutyraldehyde was added thereto, followed by heating to continue the dehydration reaction at 110 to 150 ° C. for 3 hours, and 74.5 g of water was removed by an ester tube. Subsequently, the pressure was reduced to remove excess isobutyraldehyde and toluene to obtain a hydroxyl group-containing oxazolidine compound. When 341.0 g of hexamethylene diisocyanate was added to 658.9 g of this hydroxyl group-containing oxazolidine compound and heated at 80 ° C. for 8 hours, when the NCO concentration became 0.01% by mass or less (actual NCO concentration 0.0% by mass) Was the end point of the urethanization reaction. The obtained reaction product (urethane group-containing oxazolidine compound O-1) was a translucent liquid at room temperature.

Example 1
In a kneading vessel equipped with a heating and cooling device and a nitrogen seal tube, under a nitrogen stream, 100.0 g of the isocyanate group-containing polyoxypropylene-based urethane prepolymer U-1 obtained in Synthesis Example 1 and the urethane group containing obtained in Synthesis Example 2 Oxazolidine compound O-1 18.5 g, hindered phenol antioxidant: pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] (Ciba Specialty Chemicals) Irganox 1010) 1.0 g, fatty acid (surface) treated calcium carbonate (Calphan 200M manufactured by Maruo Calcium Co., Ltd.) 90.0 g, dibutyltin dilaurate 0.1 g, p-toluenesulfonyl isocyanate 1.0 g, and tung oil 2.0 g were charged. Stir and mix until the contents are uniform, then Vacuum defoamed, filled into a container, then sealed to prepare a one-part moisture curable sealant composition.

Example 2
In Example 1, a one-component moisture-curable sealant composition was prepared in the same manner except that 6.0 g of tung oil was used instead of 2.0 g of tung oil.

Comparative Example 1
In Example 1, a one-component moisture-curable sealant composition was prepared in the same manner except that urethane group-containing oxazolidine compound O-1 18.5 and tung oil 2.0 g were not used.

Comparative Example 2
In Example 1, a one-component moisture-curable sealant composition was prepared in the same manner except that 2.0 g of paulownia oil was not used.

〔performance test〕
The following tests were performed using the one-component moisture-curable sealant compositions prepared in Examples 1 and 2 and Comparative Examples 1 and 2, respectively.
(1) Workability Extrusion time was measured according to JIS A1439: 1997 “Testing method of sealing material for building” “4.14 Extrusion test with test cartridge” (measurement temperature 23 ° C.).
(2) Slump The slump (longitudinal) was measured in accordance with “4.1 slump test” in JIS A1439: 1997 “Testing method of sealing material for building” (measurement temperature 23 ° C.).
(3) Tack-free time Measured in accordance with “4.19 Tack-free test” in JIS A1439: 1997 “Testing method of sealing material for building”.
(4) Foamability A one-component moisture-curing sealant composition is applied to the surface of a 3 mm thick lauan plywood in the form of a bead having a width of 20 mm, apex height of 10 mm, and length of 100 mm, and 23 ° C., 50%. A specimen cured and cured at a relative humidity for 14 days was cut longitudinally in the length direction with a cutter, and the presence or absence of foaming inside the cured product was visually observed.
A case where foaming was not recognized or very little was evaluated as ◯, and a case where many foams were observed was evaluated as ×.
(5) Adhesiveness of coating film Using a flexile plate having a size of about 150 mm × 100 mm and a thickness of 5 mm, a sealant composition applied to the surface with a thickness of about 3 mm was obtained at 23 ° C., 50% Those cured for 3 days, 15 days, and 30 days at relative humidity were prepared. Next, on the surface of the sealing material cured and cured for each period, a water-based top made by Nippon Paint Co., Ltd. was applied as a top coat using a brush with a thickness of about 20 to 30 μm, and 23 ° C., 50% relative humidity. The test piece after curing the paint was cured by curing the paint for 7 days.
Separately from this, test specimens after paint curing were prepared in the same manner as described above, and further immersed in water at 23 ° C. for 3 days was used as test specimens after immersion in water.
Each test specimen was cut in accordance with JIS K 5600-5-6 (1999) “Paint General Test Method, Part 5: Mechanical Properties of Coating Film, Section 6: Adhesion (Cross Cut Method)”. The test was conducted using a multi-blade cutting tool having a blade interval of 2 mm, and the adhesion of the coating film was evaluated according to the following criteria.
In Comparative Example 1, the sealant composition having a curing and curing period of 3 days was untestable because the sealant was uncured and could not be applied with a paint.
Evaluation criteria (numerical value is the number of grids to which the coating film is attached)
○: 25/25
Δ: 10-24 / 25
×: 9 or less / 25
Table 1 summarizes the raw material composition and performance of the one-component moisture-curable sealant composition.

  The one-component moisture-curable composition for further overcoating on this of the present invention includes adhesives for architectural, civil engineering, automobiles, etc., waterproofing materials, sealing materials, especially exterior walls for topcoating. Suitable for high-performance sealing materials for joints, civil joints, and automobile joints.

Claims (6)

And an isocyanate group-containing urethane prepolymer, a latent curing agent capable of generating active hydrogen group reacts with moisture, contains an oxygen-curable unsaturated compound, one-moisture for further top coating on this a curable composition,
The isocyanate group-containing urethane prepolymer is an isocyanate group-containing urethane prepolymer obtained by reacting a polyoxyalkylene-based polyol and an organic isocyanate under a condition in which an isocyanate group is excessive with respect to a hydroxyl group, and the organic isocyanate is 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,4,6-trimethylphenyl-1,3-diisocyanate, 2,4,6-triisopropylphenyl-1,3-diisocyanate, 3,3 ′ -One or more selected from the group consisting of dimethyldiphenylmethane-4,4'-diisocyanate, araliphatic polyisocyanate, aliphatic polyisocyanate and alicyclic polyisocyanate, Furthermore, top coat painting One-moisture curable composition Utame.   The latent curing agent that reacts with moisture to produce active hydrogen groups is a compound that reacts with moisture to produce primary and / or secondary amino groups. Further, a one-component moisture-curable composition for top coating.   The one-pack type moisture-curable composition for further applying a top coat on this, wherein the latent curing agent that reacts with moisture to generate active hydrogen groups is an oxazolidine compound.   The oxygen curable unsaturated compound is one or more selected from the group consisting of a drying oil, a liquid (co) polymer of a diene compound, and a modified product thereof. A one-component moisture curable composition for further top coating. Furthermore, one or more additives selected from the group consisting of curing accelerators, weathering stabilizers, fillers, adhesion promoters, thixotropic agents, storage stability improvers, colorants, and design modifiers The one-pack type moisture curable composition for performing further top coat coating on this as described in any one of Claims 1-4 containing an agent. And an isocyanate group-containing urethane prepolymer, a latent curing agent capable of generating active hydrogen group reacts with moisture, contains an oxygen-curable unsaturated compound, one-moisture for further top coating on this a curable sealant composition,
The isocyanate group-containing urethane prepolymer is an isocyanate group-containing urethane prepolymer obtained by reacting a polyoxyalkylene-based polyol and an organic isocyanate under a condition in which an isocyanate group is excessive with respect to a hydroxyl group, and the organic isocyanate is 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,4,6-trimethylphenyl-1,3-diisocyanate, 2,4,6-triisopropylphenyl-1,3-diisocyanate, 3,3 ′ -One or more selected from the group consisting of dimethyldiphenylmethane-4,4'-diisocyanate, araliphatic polyisocyanate, aliphatic polyisocyanate and alicyclic polyisocyanate, Furthermore, top coat painting One-moisture curable sealant composition Utame.