JP5332278B2 - Adhesive composition for exterior tile tension and adhesion method of exterior tile using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exterior tiling adhesive composition excellent in application work efficiency, curable without generating foams, allowing tiling under a high temperature and high humidity, excellent in retentivity (shift resistance) of a tile when applied, and excellent in water-proof bondability after cured, and a bonding method for an exterior tile using the same. <P>SOLUTION: This exterior tiling adhesive composition contains an isocyanate group-containing urethane prepolymer (A), a silicate (B) regenerating a polyol by hydrolysis due to moisture, a balloon (C) and a curing promotor (D), and the bonding method for the exterior tile uses the exterior tiling adhesive composition. The isocyanate group containing urethane prepolymer (A) is obtained by reacting a polyoxyalkylene triol having 6,000-20,000 of number-averaged molecular weight, and 0.05 meq/g or less of overall unsaturation degree, and a compound having at least one ethylenic unsaturated group and at least one hydroxy group in a molecule, with an organic polyisocyanate. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an adhesive composition for exterior tiles that is excellent in coating workability and can be applied without dislocation even under severe conditions of high temperature and humidity, and an adhesive method for exterior tiles using the same.

Conventionally, in tiled construction with exterior specifications, tiles are often pasted with mortar. This method has been implemented for many years and is an excellent method with many achievements of repeated improvements. However, the tile installation with mortar has poor workability and takes a long construction period, and cracks and peeling of tiles have occurred due to drying shrinkage of the mortar. Therefore, in order to improve these points, an elastic adhesive for a plane composed of an epoxy resin and a silicone compound having a functional group and a reactive silicon group that react with the epoxy resin has been proposed (Patent Document 1). Since this adhesive has elasticity after being cured, it is suitable for line construction and attachment of structural materials such as tiles.
In recent years, siding such as ceramics has been widely used as the outer wall of houses, and the siding surface is painted or sprayed, or the siding surface is decorated with brick, tile, masonry, etc. Attempts have been made to upgrade the design by attaching tiles to the siding surface with mortar and the like. Furthermore, in pasting tiles, joint materials are generally filled between tiles, but there is also a method of providing a space without intentionally filling joint materials and giving shadows due to the thickness of the tiles. It is done. In such a method, the adhesive to be used may deteriorate in weather resistance, causing discoloration and cracks, thereby reducing design properties. Therefore, weather resistance is required for the adhesive for exterior tiles used in such applications. When a tile is attached to the siding surface with mortar or the like, an elastic adhesive containing a silicone compound having a reactive silicon group or an adhesive containing an isocyanate group-containing urethane prepolymer is used (patent) Reference 2).

However, when the elastic adhesive for flat surfaces is applied to a siding surface (base) with poor smoothness or when the coating amount varies, the applied tile may be displaced or the joints may be distorted and the appearance There are many cases where large, thick and heavy tiles are attached to the wall surface in order to produce a more profound and high-class feeling. Inability to withstand, the applied tiles will be displaced. Further, the adhesive containing the isocyanate group-containing urethane prepolymer has an amount of carbon dioxide generated when it reacts with moisture (humidity) in the atmosphere and cures when the isocyanate group concentration is high or the curing speed is increased. Or the carbon dioxide gas is generated abruptly and foams, resulting in problems such as poor appearance, poor adhesion, and poor rubber tensile properties such as elongation. For this reason, conventionally, in order to prevent foaming due to carbon dioxide gas, a catalyst for promoting hydrolysis of a silicate using a polyol silicate ester as a latent curing agent, an organic acid salt of an organic metal such as dibutyltin dilaurate, or a tertiary amine There is known a moisture-curing one-component polyurethane prepolymer that does not substantially contain bubbles due to carbon dioxide gas inside the cured product when used as a curing agent (Patent Document 3). However, it still seems that under the severe conditions of high temperature and high humidity, the reaction of the adhesive surface layer progresses quickly and the wettability to the tile (transferability of the adhesive to the tile side) decreases, but the sticking property of the tile is poor. However, there is a problem that the tile cannot be pasted or the tile can be pasted without slipping, but the tile peels off after a while, and further, an organic metal such as dibutyltin dilaurate is used. When an organic acid salt is used as a catalyst for promoting the hydrolysis of a silicate ester, there is a problem that the water-resistant adhesiveness after curing is deteriorated, and there is a demand for a solution thereof.
JP-A-61-268720 JP 2003-49153 A JP-A-63-191820

  The purpose of the present invention is that the coating workability is good, it cures without foaming, and the tile can be pasted even under severe conditions of high temperature and high humidity, and it has excellent retention of the tile during construction (slip resistance) And the adhesive composition for exterior tile tension excellent in the water-resistant adhesiveness after hardening, and the adhesion | attachment method of an exterior tile using the same are provided.

In order to solve the above-mentioned problems, the present inventors have intensively studied. As a result, the polyoxyalkylene triol having a number average molecular weight of 6,000 to 20,000 and a total unsaturation of 0.05 meq / g or less, and ethylenic properties Regenerating a polyol by hydrolysis with an isocyanate group-containing urethane prepolymer (A) obtained by reacting a compound having at least one unsaturated group and a hydroxyl group in the molecule with an organic polyisocyanate. The present inventors have found that the above-mentioned problems can be solved by using the silicate ester (B), the balloon (C), and the curing accelerator (D), which have been able to be prepared, and have completed the present invention.
That is, this invention is shown by the following (1)-(6).

(1) An isocyanate group-containing urethane prepolymer (A), a silicate ester (B) capable of regenerating a polyol by hydrolysis with moisture, a balloon (C), and a curing accelerator (D) It is an adhesive composition for exterior tile covering, and the isocyanate group-containing urethane prepolymer (A) has a number average molecular weight of 6,000 to 20,000 and a total unsaturation level of 0.05 meq / g or less. It is an isocyanate group-containing urethane prepolymer obtained by reacting a certain polyoxyalkylenetriol, a compound having at least one ethylenically unsaturated group and a hydroxyl group in the molecule, and an organic polyisocyanate. The exterior tiled adhesive composition.
(2) Silicate ester (B) capable of regenerating a polyol by hydrolysis with moisture is a compound obtained by a dealcoholization reaction between neopentyl glycol and a monovalent alcohol silicate ester. (1) The adhesive composition for exterior tiling.
(3) The balloon (C) is one or a mixture of two or more selected from the group consisting of Shirasu balloon, silica balloon, ceramic balloon, glass balloon, alumina balloon and zirconia balloon. 2) Adhesive composition for exterior tiles.
(4) The said accelerator (D) contains at least 1,8-diazabicyclo [5,4,0] undec-7-ene and tetra-n-butoxytitanium according to the above (1) to (3). Any of the exterior tiled adhesive compositions.
(5) Further, as an additive, one or any two selected from the group consisting of a weathering stabilizer, a filler, a plasticizer, an adhesion promoter, a thixotropic agent, a storage stability improver, a colorant and a solvent The adhesive composition for exterior tiles according to any one of (1) to (4), comprising the above mixture .
(6) An exterior tile characterized by adhering an exterior tile and / or an exterior mosaic tile to an outer wall material using the exterior tile tensioning adhesive composition according to any one of (1) to (5). Bonding method.

  For the first time according to the present invention, the coating workability is good and it is cured without foaming, and the tile can be pasted even under severe conditions of high temperature and high humidity, excellent in the retention property (displacement resistance) of the tile during construction, And it became possible to provide the adhesive composition for exterior tile tension excellent in the water-resistant adhesiveness after hardening, and the adhesion | attachment method of an exterior tile using the same.

The present invention will be described in detail below.
The isocyanate group-containing urethane prepolymer (A) used in the present invention has a polyoxyalkylene triol having a number average molecular weight of 6,000 to 20,000 and a total unsaturation of 0.05 meq / g or less, and an ethylenic group. It is obtained by reacting a compound having at least one unsaturated group and one hydroxyl group in the molecule with an organic polyisocyanate under an excess of isocyanate groups.
Specifically, the polyoxyalkylene triol, the compound having at least one ethylenically unsaturated group and a hydroxyl group in each molecule, and the organic polyisocyanate have an isocyanate group / total hydroxyl group equivalent ratio of 1 as a total of raw materials. It can be suitably produced by reacting simultaneously or sequentially in the range of 2 to 6.0, more preferably 2.0 to 5.0, and particularly 3.0 to 4.5. If the equivalent ratio is less than 1.2, the resulting urethane prepolymer has too few cross-linking points, and the elongation and tensile strength after curing of the adhesive composition for exterior tiles are lowered, resulting in rubber elastic properties and adhesive properties. If the equivalence ratio exceeds 6.0, the amount of carbon dioxide gas generated increases when reacting with moisture, which causes foaming.

As a polyoxyalkylene triol having a number average molecular weight of 6,000 to 20,000 and a total unsaturation of 0.05 meq / g or less, an alkylene oxide is opened to a compound containing 3 or more active hydrogens as an initiator. Examples thereof include those obtained by cycloaddition polymerization.
Examples of the initiator include low-molecular polyhydric alcohols such as glycerin, trimethylolpropane, pentaerythritol, and diglycerin, saccharide-based low-molecular polyhydric alcohols such as sorbitol, sucrose, glucose, lactose, and sorbitan, pentane- Examples include low molecular weight polyamines such as 1,2,5-triamine, and low molecular weight polyoxyalkylene polyols obtained by reacting at least one of these with alkylene oxide. Of these, the initiator preferably contains three active hydrogens.
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 triols are specifically polyoxyethylene triol, polyoxypropylene triol, polytetramethylene ether triol, poly (oxyethylene) -poly (oxypropylene) -random or block copolymerized triol, poly (Oxypropylene) -poly (oxybutylene) -random or block copolymerized triols can be mentioned.
The polyoxyalkylene triol is required to have a number average molecular weight of 6,000 to 20,000 for reasons such as good workability, and preferably 10,000 to 18,000.
Further, the polyoxyalkylene-based triol is required to have a total unsaturation of 0.05 meq / g or less, particularly 0.03 meq / g, obtained using a catalyst such as a double metal cyanide complex. The following are preferable, and the molecular weight distribution [ratio of weight average molecular weight (Mw) and number average molecular weight (Mn) in terms of polystyrene by gel permeation chromatography (GPC) = Mw / Mn] is 1.6 or less, In particular, a narrow one of 1.0 to 1.3 is preferable.
In the present invention, the polyoxyalkylene-based triol is 50% by mass or more, more preferably 80% by mass or more, particularly preferably 90% by mass or more of the portion excluding the hydroxyl group of 1 mol of 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 of the molecule excluding the hydroxyl group. Most preferred is a triol composed of polyoxyalkylene.
Any of these may be used alone or in combination of two or more.
Of these, a triol comprising 95% by mass or more of the molecule excluding the hydroxyl group is preferably polyoxyalkylene, and most preferably polyoxypropylene triol.

The compound having at least one ethylenically unsaturated group and one hydroxyl group in the molecule includes one or more ethylenically unsaturated groups that are reactively cured by light such as acryloyl group or methacryloyl group in the molecule, and isocyanate. Examples thereof include compounds having at least one hydroxyl group having reactivity with a group in the molecule. Specifically, for example, a hydroxyl group-containing acrylate compound such as pentaerythritol triacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, a hydroxyl group-containing methacrylate compound, an epoxy group such as a bisphenol A type epoxy compound, acrylic acid or methacrylic acid. For example, a compound in which an acryloyl group, a methacryloyl group and a hydroxyl group are introduced, or a polyvinyl cinnamate having a hydroxyl group. Monomers and oligomers having a molecular weight of 10,000 or less, and a molecular weight of 5,000 or less are preferred. Particularly preferred are those having at least one acryloyl group and / or methacryloyl group per molecule and containing at least one hydroxyl group per molecule.
Any of these may be used alone or in combination of two or more.

Specific examples of the organic polyisocyanate include aromatic diisocyanates such as phenylene diisocyanate, diphenyl diisocyanate, naphthalene diisocyanate, diphenylmethane diisocyanate (MDI), tolylene diisocyanate, diphenyl ether diisocyanate, and araliphatic diisocyanates such as xylylene diisocyanate, hexa Aliphatic diisocyanates such as methylene diisocyanate, pentamethylene diisocyanate, propylene diisocyanate, butylene diisocyanate, cyclohexane diisocyanate, methylene bis (cyclohexyl isocyanate), isophorone diisocyanate, polymethylene polyphenyl polyisocyanate (crude MDI) Polymeric MDI) and the like. In addition, modified isocyanates containing one or more uretdione bonds, isocyanurate bonds, burette bonds, allophanate bonds, uretonimine bonds, carbodiimide bonds, urethane bonds, urea bonds and the like obtained by modifying these organic polyisocyanates can also be used.
These can be used alone or in combination of two or more.
Among these, the aromatic group diisocyanate, the fat having a low viscosity of the resulting isocyanate group-containing urethane prepolymer, a good elongation and strength after curing of the adhesive composition for exterior tile tension, and a good weather resistance. One or more selected from the group consisting of group diisocyanates and alicyclic diisocyanates are preferred, and xylylene diisocyanate is more preferred.

The production conditions of the isocyanate group-containing urethane prepolymer (A) may be the production conditions of a conventionally known urethane prepolymer. That is, the polyoxyalkylene triol from which the moisture content has been removed, a compound having at least one ethylenically unsaturated group and a hydroxyl group in the molecule, respectively, and an organic polyisocyanate are mixed under a normal pressure such as nitrogen or argon. It can be obtained by reacting at a reaction temperature of 40 to 100 ° C. for 1 to 10 hours in the presence of an active gas.
At this time, an organic solvent inert to an isocyanate group such as toluene and xylene can be used, but it is preferable not to use or to reduce the amount used as much as possible.

  Furthermore, a reaction catalyst can also be used. A known urethanization catalyst can be used as the reaction catalyst. That is, a salt of a metal such as zinc, tin, lead, zirconium, bismuth, cobalt, manganese, iron and the like and an organic acid such as octylic acid and naphthenic acid, such as tin octylate and zirconium octylate, dibutyltin diacetylacetonate, Organometallic chelates such as zirconium tetraacetylacetonate and titanium tetraacetylacetonate, organometallic compounds such as dibutyltin dilaurate and dioctyltin dilaurate, and salts of organic acids and organic acids, triethylenediamine, triethylamine, tri-n- An organic amine such as butylamine or a salt thereof can be used.

  The isocyanate group content of the isocyanate group-containing urethane prepolymer (A) is preferably 0.3 to 35.0% by mass, more preferably 0.3 to 10.0% by mass, and particularly 1.0 to 6.0% by mass. Is preferred. 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 35.0% by mass, the number of cross-linking 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 silicate ester (B) that can be used in the present invention to regenerate a polyol by hydrolysis with moisture is, for example, a monovalent product formed by substituting silicate esters of various monohydric alcohols with a polyol. It can be obtained by distilling alcohol [the following formula (1)] or dehydrohalogenating a silicic acid halogen compound and a polyol [the following formula (2)], but obtained by the former method. Are preferred.

  The silicate ester which is the product of the formulas (1) and (2) includes not only the chain ester but also the following cyclic silicate ester. In this regard, reference is made to Journal of the American Chemical Society (JACS) 69 (1947) 2689-2691.

Silicic acid esters of monohydric alcohols include tetraalkoxysilanes such as tetramethoxysilane and tetraethoxysilane, trialkoxysilanes such as alkyltrimethoxysilane and alkyltriethoxysilane, dialkoxy such as dialkyldimethoxysilane and dialkyldiethoxysilane. Examples thereof include monoalkoxysilanes such as silane and trialkylmonomethoxysilane, and alkoxysilane coupling agents such as 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropylmethyldiisopropenoxysilane. These can be used alone or in admixture of two or more. Among these, an alkoxysilane coupling agent is preferable from the point of having an adhesion imparting effect, and 3-glycidoxypropyltrimethoxysilane is particularly preferable.
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.
Examples of the polyol include ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, neopentyl glycol, hexane glycol, glycerin, trimethylolpropane, polyethylene glycol, and polytetramethylene diol. Of these, polyfunctional alcohols having a primary hydroxyl group are preferred. These can be used alone or in admixture of two or more. Of these, neopentyl glycol is particularly preferred because the resulting silicate ester has a low viscosity.
At the time of synthesizing the silicate ester by transesterification of the di, tri, or tetraalkoxysilane with a polyol, a part of the raw material alkoxysilane can be left. However, in this case, the monohydric alcohol generated by hydrolysis reacts with the isocyanate group-containing urethane prepolymer to hinder cross-linking polymerization. In order to suppress this side reaction, a secondary or tertiary monohydric alcohol is added to the remaining alkoxysilane, alcoholysis is performed, and a primary alcohol such as methanol or ethanol is distilled out of the system. And a silicate ester consisting of a secondary or tertiary monohydric alcohol. This silicate ester generates a polyol and a secondary or tertiary monohydric alcohol by hydrolysis, but the secondary or tertiary monohydric alcohol reacts slowly with an isocyanate group, so a primary polyol such as ethylene glycol. The isocyanate group-containing urethane prepolymer is polymerized preferentially by the reaction between the isocyanate group and the isocyanate group, and the secondary or tertiary monohydric alcohol evaporates out of the system without being reacted.
Examples of the secondary or tertiary monohydric alcohol include isopropanol, sec-butanol, 2-octanol, tert-butanol, tert-octanol and 2,3,4-trimethyl-1,3-pentadiol monobutyrate. And monohydric alcohols.

  Examples of the silicate ester (B) that can be hydrolyzed by moisture to regenerate the polyol include cyclic silicate esters in addition to the chain ester. Specifically, for example, as dialkoxysilane, dimethyl / ethylenedioxysilane dimer, dimethyl (trimethylene-1,3-dioxy) silane, dimethyl (tetramethylene-1,4-dioxy) silane, dimethyl (2 , 2'-oxydiethoxy) silane, dimethyl (2,2'-ethylenedioxydiethoxy) silane, tetramethyl-1,3- (2,2'-oxydiethoxy) disiloxane, and tri Examples of alkoxysilanes include viscous liquid products obtained by condensing two molecules of methyltrimethoxysilane, two molecules of γ-glycidoxypropyltrimethoxysilane, and three molecules of neopentyl glycol.

In the present invention, the mixing ratio between the isocyanate group-containing urethane prepolymer (A) and the silicate ester (B) is such that the hydroxyl group of the polyol regenerated by hydrolysis of the silicate ester is 1 equivalent of the isocyanate group contained in the urethane prepolymer. It is preferable to be 0.2 to 1.2 equivalent, more preferably 0.3 to 1.0 equivalent. When the hydroxyl group of the regenerated polyol is less than 0.2 equivalents, excess isocyanate groups react with moisture and cause foaming. Conversely, when it exceeds 1.2 equivalents, the molecular ends can be stopped by hydroxyl groups and polymerized. In addition, the tackiness is poor and the adhesiveness after curing is also unfavorable.
In the present invention, the reaction between the silicate ester (B) that can be hydrolyzed with moisture to regenerate the polyol and the moisture in the air and the reaction between the isocyanate group and the primary hydroxyl group are the reaction between the isocyanate group and the moisture. It is much faster than. Therefore, in the presence of an isocyanate group-containing urethane prepolymer and a silicate ester, when the mixture comes into contact with moisture, hydrolysis of the silicate ester (the following formula (3)) results in a reaction between the moisture and the isocyanate group [ Prior to the following formula (5)], a urethanization reaction [following formula (4)] of the regenerated polyol and isocyanate group occurs to obtain a polyurethane resin.

  That is, the reaction rate is (3)> (5). In general, the reaction rate between an isocyanate group and a primary hydroxyl group is greatly “faster ((4)> (5))” than the reaction between an isocyanate group and water. Therefore, the reaction of the formula (5) is substantially As a result, foaming of the cured product by carbon dioxide gas is prevented.

The balloon (C) used in the present invention is used to ensure good retention of the tile after construction, and the inside is hollow and the average particle size is 5 μm or more, further 5 to 400 μm, especially 20 to The thing of 400 micrometers is preferable. There are various bulk specific gravities (g / cm ³ ), and those having 0.05 to 0.6, particularly 0.1 to 0.25 are preferable. When the average particle size of the balloon is less than 5 μm, the holding property of the tile after construction is lowered, and when it exceeds 400 μm, the physical properties such as workability, modulus and durability are deteriorated. Examples of the balloon material include inorganic materials such as glass, shirasu, silica, and ceramics, and organic materials such as phenol resin, urea resin, polystyrene, and saran. A composite material and an organic material may be combined or stacked to form a plurality of layers. The balloon may be the same material balloon or a mixture of different types of balloons. Furthermore, the balloon can use what processed or coated the surface, and can also use what processed the surface with various surface treating agents.
Specifically, inorganic balloons are generally called Shirasu balloons, silica balloons, and ceramic balloons made of burnt ash from thermal power plants (E-SPHERES from Taiheiyo Cement Co., Ltd.). Etc.), glass balloons made of glass, alumina balloons, zirconia balloons and the like. In the present invention, one or a mixture of two or more of shirasu balloon, silica balloon, ceramic balloon, glass balloon, alumina balloon and zirconia balloon is preferable.
In the adhesive for exterior tiles of the present invention, the balloon (C) is an isocyanate group-containing urethane prepolymer from the viewpoint that tiles can be attached even under severe conditions of tile retention, viscosity, high temperature, and high humidity (transferability). It is preferable to mix 0.5 to 50 parts by mass, further 1 to 30 parts by mass, and particularly 2 to 20 parts by mass with respect to 100 parts by mass of the polymer (A).
The dispersing machine used for blending the balloon can be any apparatus that kneads and disperses while applying shear. Specifically, for example, a uniaxial kneading and dispersing machine such as a high-speed disperser (Dilzoba). , A multi-axis kneading disperser such as a biaxial planetary mixer, a disperser combining a high-speed disperser and a biaxial planetary mixer, a kneader, etc. Among them, a multi-axis kneading disperser is preferable because of its good dispersibility. . When using a biaxial kneading disperser, it is preferable to add balloon (C) to the isocyanate group-containing urethane prepolymer (A) and knead for 0.5 to 10 hours, particularly 1 to 6 hours. Less than 0.5 hours, the retention of tiles is inferior, and even after 10 hours, there is no change in retention, the number of balloons that are broken and no longer hollow is increased, the viscosity increases, the working time is increased, and the cost is increased. Cause up.

The curing accelerator (D) used in the present invention acts as a reaction curing acceleration catalyst between the polyol regenerated from the silicate ester (B) and the isocyanate group of the isocyanate group-containing urethane prepolymer (A). It also acts as a hydrolysis catalyst for the silicate ester (B), which can be hydrolyzed by moisture to regenerate the polyol. 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 organotin compounds such as dibutyltin distearate, dioctyltin dilaurate, dioctyltin diversate, dibutyltin oxide, dibutyltin bis (triethoxysilicate), a reaction product of dibutyltin oxide and phthalate, dibutyltin diacetylacetate Nert, 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-n -Titanates such as butoxy titanium (TBT) and tetrapropyl titanate, organic bismuth compounds such as bismuth octylate and bismuth versatate, triethylamine, tributylamine, triethylenediamine, hexamethylenetetramine, 1,8-diazabicyclo [5, 4,0] Undec-7-ene (DBU), 1,4-diazabicyclo [2,2,2] octane, N-methylmorpholine, N-ethylmorpholine Tertiary amines etc., or a salt such as these amines and carboxylic acids. These can be used alone or in combination of two or more. Among these, a mixed catalyst containing at least TBT and DBU is preferable.
It is preferable that the usage-amount of a hardening accelerator (D) is 0.005-10 mass parts with respect to 100 mass parts of isocyanate group containing urethane prepolymer (A), Furthermore, 0.1-2 mass parts.

  As an additive used in the present invention, one or any two or more of a weather resistance stabilizer, a filler, a plasticizer, an adhesion promoter, a thixotropic agent, a storage stability improver, a colorant, a solvent and the like are used. The mixture of is preferably mentioned.

  The weather stabilizer is used to prevent oxidative deterioration and thermal deterioration of the exterior tiled adhesive composition and maintain the weather resistance, and examples thereof include an antioxidant and an ultraviolet absorber.

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.

  Fillers, plasticizers, adhesion-imparting agents, thixotropic agents, storage stability improvers (dehydrating agents), colorants, solvents, etc. are reinforced, increased, improved adhesiveness, improved wrinkling, and improved storage stability. It can be used for coloring, improving workability and the like.

  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 materials such as inorganic powder fillers such as calcium carbonate, light calcium carbonate, magnesium carbonate, alumina, calcium oxide, magnesium oxide, granular fillers such as crushed cold water, fibrous fillers such as asbestos, glass fiber, and carbon fiber Fillers, or fillers whose surfaces are treated with organic substances such as fatty acids, wood flour, walnut flour, rice husk flour, pulp powder, cotton chips, rubber powder, polyamide resin, polyester resin, polyurethane resin, silicone resin, Polyvinyl chloride resin, vinyl acetate resin, polyethylene and polypropylene In addition to organic fillers such as thermoplastic resins such as plastic resins, acrylic resins, epoxy resins, phenol resins, urea resins, melamine resins, or powders of thermosetting resins, difficulties such as magnesium hydroxide and aluminum hydroxide Examples include flame retardant fillers, and those having a particle size of 0.01 to 1,000 μm are preferable.

  Examples of plasticizers include phthalates such as dibutyl phthalate, diheptyl phthalate, dioctyl phthalate, diisononyl phthalate, di (2-ethylhexyl) phthalate, butyl benzyl phthalate, butyl phthalyl butyl glycolate, dioctyl adipate, dioctyl seba Low molecular weight plasticizers having a molecular weight of less than 500, such as non-aromatic dibasic acid esters such as ket, phosphate esters such as tricresyl phosphate and tributyl phosphate, and halogenated aliphatic compounds such as chlorinated paraffin, and the like. Examples of the high molecular weight type plasticizer having a molecular weight of 500 or more include polyester plasticizers such as polyesters from dicarboxylic acids and glycols, etherification of polyethylene glycol and polypropylene glycol, Polyethers such as saccharide-based polyethers obtained by addition polymerization of ethylene oxide or propylene oxide to saccharide polyhydric alcohols such as stearic derivatives and sucrose, and polystyrene such as poly-α-methylstyrene And low-viscosity (meth) acrylic acid ester-based copolymers. Among these, a high molecular weight type plasticizer having a molecular weight of 500 or more is preferable in that it hardly migrates (bleeds) to the surface of the cured product.

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.

  Examples of the 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 petroleum solvents containing these. Any of these may be used as long as they do not react with each component of the composition.

  The total amount of weathering stabilizer, filler, plasticizer, adhesion promoter, thixotropic agent, storage stability improver (dehydrating agent), colorant and solvent is the isocyanate group-containing urethane prepolymer (A). 0 to 1,000 parts by mass, particularly 10 to 500 parts by mass are preferable with respect to 100 parts by mass.

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

Next, a method for bonding an exterior tile according to the present invention will be described.
The method for adhering an exterior tile according to the present invention is a method of adhering an exterior tile and / or an exterior mosaic tile to an outer wall material using the adhesive composition for exterior tile tension.
The exterior material is a building material used on the outdoor side of a house or structure in order to protect the house or structure from a natural environment such as rain, wind, light, or heat, and the outer wall material is an exterior material. It is a building material used as an outer wall.
Tile is a fired product of viscosity, and is one of the most durable building finishing materials and widely used for interior and exterior and flooring. There are three types of tiles used in construction: porcelain, porcelain, and ceramic, and brick tiles, and mosaics for exterior, interior, and floor. There are tiles called tiles. Mosaic tiles with a surface area of 50 cm ² or less are called mosaic tiles. The tiles handled here are JIS A5209-1994 ceramic tiles that are one of the building finishing materials and are mainly used as exterior materials. Refers to tiles defined in

Hereinafter, the present invention will be described in more detail with reference to examples.
Synthesis Example 1 (Neopentyl glycol silicate ester)
In a reaction vessel equipped with a stirrer, thermometer, nitrogen seal tube, reflux condenser and heating / cooling device, 312.5 g of neopentyl glycol, 3-glycidoxypropyltrimethoxysilane (manufactured by Nihon Unicar Co., Ltd., A-187) 475 0.1 g and 0.001 g of tetrabutyl titanate as a reaction catalyst were added, stirred and heated while flowing nitrogen gas, and refluxed for 2 hours. The liquid temperature decreased from 138 ° C to 100 ° C. Thereafter, the reflux condenser was removed, and heating was continued until 200 ° C. while distilling by-product methanol out of the system, and a light yellow silicate liquid 595 having no absorption by hydroxyl groups at 3300-3500 cm ⁻¹ by IR. 0.6 g was obtained. The amount of methanol distilled was 192 g.
This liquid showed no neopentylglycol peak even when subjected to gas chromatography [FID, Gaschromac 55-column (manufactured by Gaschrom Industries Ltd., oven temperature 200 ° C.)]. As a reference, when the liquid was hydrolyzed by adding water, and subjected to gas chromatography, the peak of neopentyl glycol was detected almost quantitatively and confirmed to be regenerated.

Synthesis Example 2 (Isocyanate group-containing urethane prepolymer PU-1)
In a reaction vessel equipped with a stirrer, thermometer, nitrogen seal tube and heating / cooling device, polyoxypropylene triol (PML-S3011, manufactured by Asahi Glass Co., Ltd., number average molecular weight 10,000, total degree of unsaturation 0.02 meq / g) 1000.0 g (OH equivalent: 0.3000) and 25.0 g (OH equivalent: 0.08389) of pentaerythritol triacrylate (Alinix M-305 manufactured by Toa Gosei Co., Ltd.) were charged and stirred with xylylene diisocyanate (Mitsui XDI manufactured by Chemical Polyurethanes Co., Ltd., molecular weight 188) 115.3 g (NCO equivalent: 1.227) and Neostan U-600 (manufactured by Nitto Kasei Co., Ltd.) 0.12 g were added, followed by heating to 70-80 ° C. for 4 hours. The reaction was terminated when the isocyanate group content became less than the theoretical value (3.11% by mass) after stirring, and the isocyanate Was prepared urethane prepolymer PU-1.
This isocyanate group-containing urethane prepolymer PU-1 was a liquid at room temperature with an isocyanate group content of 2.98% by mass, a viscosity of 18,600 mPa · s / 25 ° C., measured by titration.

Example 1
In a kneading vessel with a heating and cooling device and a nitrogen seal tube, under a nitrogen stream, 100.0 g of the isocyanate group-containing urethane prepolymer PU-1 obtained in Synthesis Example 2, petroleum solvent (ExxonMobil, Exol D40) 30.0 g, 30.0 g of diisononyl phthalate, 275.0 g of heavy calcium carbonate previously dried in a dryer at 90 to 100 ° C. to a moisture content of 0.05% by mass or less, similarly oxidized in advance in a dryer 27.5 g of titanium and 85.0 g of a surface-treated calcium carbonate (manufactured by Maruo Calcium Co., Calfine 200M) previously dried in a drier were charged and stirred and mixed until the contents were uniform. Next, 10.0 g of glass balloon (manufactured by Tokai Kogyo Co., Ltd., Cellstar Z-27), organic polyisocyanate (manufactured by Sumika Bayer Urethane Co., Ltd., Sumidur N-3300) 15 previously dried in a dryer at 90 to 100 ° C. 15 1.0 g, 11.3 g of neopentyl glycol silicate ester obtained in Synthesis Example 1 and 5.0 g of p-toluenesulfonyl isocyanate were charged and stirred and mixed until the contents were uniform. Next, 0.18 g of 1,8-diazabicyclo [5,4,0] undec-7-ene (manufactured by Wako Pure Chemical Industries, DBU), 0.12 g of tetra-n-butoxy titanium (manufactured by Nippon Soda Co., Ltd., TBT) Was stirred and mixed until the contents were uniform, degassed under reduced pressure, filled in a container and sealed, to prepare an adhesive composition for exterior tiling.

Example 2
In Example 1, an exterior tiled adhesive composition was prepared in the same manner except that 15.0 g of a glass balloon (manufactured by Tokai Kogyo Co., Ltd., Cellstar Z-27) was used.

Example 3
In Example 1, an adhesive composition for exterior tiling was prepared in the same manner except that 0.06 g of DBU was used.

Example 4
In Example 1, an exterior tiled adhesive composition was prepared in the same manner except that 0.06 g of TBT was used.

Example 5
An adhesive composition for exterior tiling was prepared in the same manner as in Example 1 except that 12.7 g of neopentyl glycol silicate was used.

Comparative Example 1
In Example 1, an adhesive composition for exterior tiling was prepared in the same manner except that no glass balloon was used.

Comparative Example 2
An adhesive composition for exterior tiling was prepared in the same manner as in Example 1, except that neopentyl glycol silicate was not used.

Comparative Example 3
In Example 1, an adhesive composition for exterior tiling was prepared in the same manner except that the curing accelerators DBU and TBT were not used.

Performance test (viscosity)
Using a B8U type rotational viscometer, the viscosity at 25 ° C. was measured with a No7 rotor at 10 revolutions per minute and subsequently at 100 revolutions per minute.
[Foaming]
A test specimen obtained by applying an adhesive composition for exterior tiling to a flat surface with a thickness of 2 mm on the surface of a mortar plate having a width of 70 mm, a length of 150 mm, and a thickness of 10 mm, followed by curing at 40 ° C. and 30% relative humidity for 1 day. Was observed visually.
A case in which significant blistering due to foaming was not observed or extremely small was evaluated as ◯, and a case where a large number of blisters were observed was evaluated as ×.
(Slip resistance)
JIS A5557; (2006) “Organic Adhesive for Exterior Tiling” 6.3.6 Evaluation was made according to the displacement resistance test method. A ceramic siding was used as a base material, and an adhesive composition for exterior tiling was applied in an amount of 1.5 kg / m ² using a comb iron. Next, a tile having a weight of about 500 g (made by Inax Co., Ltd., size: length 60 mm × width 230 mm × thickness 15 mm) was pasted on this, and after 24 hours, the length of deviation from the reference line was measured.
A sample having a deviation of less than 1 mm was evaluated as ◯, and a sample having a deviation of 1 mm or more was evaluated as ×.
[Adhesion]
Immediately after applying the adhesive composition for exterior tiling to a flat surface with a thickness of 1.5 mm on the surface of a mortar flat plate placed almost horizontally, it was left still in a constant temperature and humidity chamber at 40 ° C. and 30% relative humidity for 30 minutes. I put it. Next, the mortar board coated with the adhesive composition for exterior tile tension is taken out, and a mosaic tile (length 45 mm × width 45 mm × thickness 7 mm) in which a steel ball of φ1.0 mm is attached as a spacer on the back of the tile is obtained. The spacer was pressed by hand until it hits the mortar surface. Subsequently, the mosaic tile was removed from the mortar board, and the adhesive composition for exterior tiling attached to the back of the mosaic tile was visually observed.
The case where adhesion of the adhesive composition for exterior tiling is recognized to 70% or more of the area of the back surface of the tile, ○, the case where adhesion of the adhesive is recognized to 30% or more and less than 70%, △, 30% The case where adhesion of the adhesive was recognized to less than was evaluated as x.
[Storage stability]
JIS A5557; (2006) “Organic Adhesive for Exterior Tiling” 6.3.1 Evaluation was made by the storage stability test method.
A case where the change in mass was within 5% and was homogeneous and no foreign matter was observed was rated as ◯, and a case where the change in mass exceeded 5% or a foreign matter was found not uniform was evaluated as x.
[Adhesive strength]
JIS A5557; (2006) “Organic Adhesive for Exterior Tiling” 6.3.3 Adhesive Strength Test method was used to evaluate the adhesive strength after standard curing and the adhesive strength after immersion in alkaline hot water.
Regarding the bond strength after standard curing, the maximum load until breakage is 60 N / cm ² or more and the cohesive failure rate is 75% or more, the maximum load until breakage is less than 60 N / cm ² or cohesive failure Those having a rate of less than 75% were evaluated as x.
Regarding the adhesive strength after immersion in hot alkali water, the maximum load until breaking is 40 N / cm ² or more and the cohesive failure rate is 50% or more, and the maximum load until breaking is 40 N / cm ^2. Less than or less than 50% of the cohesive failure rate.
The raw material compositions and test results are summarized in Tables 1 and 2 below.

Claims (6)

An exterior containing an isocyanate group-containing urethane prepolymer (A), a silicate ester (B) that can be hydrolyzed by moisture to regenerate a polyol, a balloon (C), and a curing accelerator (D) A tiling adhesive composition comprising:
The isocyanate group-containing urethane prepolymer (A) is a polyoxyalkylene triol having a number average molecular weight of 6,000 to 20,000 and a total degree of unsaturation of 0.05 meq / g, an ethylenically unsaturated group, and The adhesive composition for exterior tile tension, which is an isocyanate group-containing urethane prepolymer obtained by reacting a compound having at least one hydroxyl group in the molecule with an organic polyisocyanate.   The silicate ester (B) capable of regenerating a polyol by hydrolysis with moisture is a compound obtained by a dealcoholization reaction between neopentyl glycol and a silicate ester of a monohydric alcohol. 2. Adhesive composition for exterior tiles described in 1.   The exterior according to claim 1 or 2, wherein the balloon (C) is one or a mixture of two or more selected from the group consisting of a shirasu balloon, a silica balloon, a ceramic balloon, a glass balloon, an alumina balloon, and a zirconia balloon. Tiling adhesive composition.   The said hardening accelerator (D) contains at least 1,8-diazabicyclo [5,4,0] undec-7-ene and tetra-n-butoxytitanium as described in any one of Claims 1-3. Adhesive composition for exterior tiles. Further, as an additive, one or any mixture of two or more selected from the group consisting of a weathering stabilizer, a filler, a plasticizer, an adhesion promoter, a thixotropic agent, a storage stability improver, a colorant, and a solvent. The adhesive composition for exterior tile tension as described in any one of Claims 1-4 containing this.   Adhesion of an exterior tile, wherein the exterior tile and / or the exterior mosaic tile is adhered to an outer wall material using the adhesive composition for exterior tile tension according to any one of claims 1 to 5. Method.