JP6206025B2 - 1-pack room temperature moisture curable adhesive composition for wood flooring - Google Patents

Description

  The present invention relates to a one-pack type room temperature moisture for a wooden floor material containing an oxyalkylene-based polymer having a silicon-containing group having a hydroxyl group or a hydrolyzable group bonded to a silicon atom and capable of crosslinking by forming a siloxane bond. It is a curable adhesive composition, and relates to an adhesive composition that can reduce the interval (gap) between seams between wooden floor materials when the wooden floor materials are bonded. Hereinafter, a silicon-containing group having a hydroxyl group or a hydrolyzable group bonded to a silicon atom and capable of crosslinking by forming a siloxane bond is also referred to as a crosslinkable silicon group.

  The oxyalkylene-based polymer having a crosslinkable silicon group has a property that it is crosslinked even at room temperature by the action of moisture such as moisture in the air to produce a rubber-like cured product having elasticity. For this reason, this polymer is used as a sealing material or an adhesive. When used in a sealing material or an adhesive, a compound having a crosslinkable silicon group and an amino group excellent in adhesion imparting effect as an adhesion imparting agent or an imine derivative of this compound (hereinafter referred to as an amino group-containing compound and this compound) In some cases, imine derivatives are also referred to as aminosilanes). In addition, a stable organotin silanol condensation catalyst having a high curing rate may be used as a curing catalyst.

  Patent Document 1 cures when a curable composition containing an oxyalkylene polymer having a crosslinkable silicon group, aminosilanes, and an organotin silanol condensation catalyst is used as an adhesive for a floor material (floor material, flooring material). It is described that since the object has elasticity, it is possible to prevent floor noise when walking. However, when the flooring is a wooden flooring, Patent Document 1 has a problem that the flooring shrinks as the flooring dries, and the joint interval (gap) between the wooden flooring becomes large. Is described. Moreover, when it uses for adhesion | attachment with a wooden flooring and a floor heating panel, the problem that drying is accelerated | stimulated with a heat | fever and the gap becomes still larger also arises. If the gap is large, the appearance will not be good, and dust and dust will enter the gap.

  Patent Document 2 discloses that the gap can be reduced by increasing the tensile modulus and hardness of the cured adhesive. According to Patent Document 2, when a large amount of inorganic filler is added, the tensile modulus and hardness of the cured product are increased. Patent Document 1 discloses that the use of a plate-like filler can reduce the gap. Patent Document 2 and Patent Document 4 disclose that the gap can be reduced even if a needle-like filler is used. Furthermore, Patent Document 3 discloses that the gap can be further reduced by adding an epoxy resin in addition to the inorganic filler.

  Thus, the prior art suggests that in order to reduce the gap, an adhesive that gives a hardened product with higher hardness by blending a filler or using an epoxy resin together is desirable. Yes. However, it has been found that even an adhesive in which a large amount of a filler is added to an oxyalkylene polymer having a crosslinkable silicon group may increase the gap.

JP 2006-143985 A JP 2007-162958 A JP-A-2005-264126 JP 2006-117753 A

  The problem to be solved by the present invention is a one-pack type room temperature moisture curable adhesive composition for wood flooring containing an oxyalkylene polymer having a crosslinkable silicon group, aminosilanes and a tetravalent tin compound. Another object of the present invention is to provide a one-component room temperature moisture curable adhesive composition that reduces the gap between floor materials different from the curable compositions disclosed in Patent Documents 1 to 4.

  When the present inventors further add an alicyclic epoxy compound having one epoxy group in the molecule, a one-pack type room temperature moisture-curable adhesive composition for a wooden flooring that can reduce the space of the flooring is obtained. Found that can be obtained. That is, the present invention is the following one-component room temperature moisture curable adhesive composition for wood flooring.

  The one-pack type room temperature moisture-curable adhesive composition for a wooden floor material of the present invention includes (A) a silicon-containing material having a hydroxyl group or a hydrolyzable group bonded to a silicon atom and capable of crosslinking by forming a siloxane bond. 100 parts by mass of an oxyalkylene polymer having a group, (B) a silicon-containing group and an amino group having a hydroxyl group or hydrolyzable group bonded to a silicon atom in the molecule and capable of crosslinking by forming a siloxane bond 0.1-20 parts by mass of the compound or imine derivative of the compound, 0.1-10 parts by mass of (C) tetravalent tin compound, and (D) an alicyclic epoxy having one epoxy group in the molecule 1-100 mass parts of compounds are contained, It is characterized by the above-mentioned.

  The (C) tetravalent tin compound is preferably a dialkyl tin compound.

  It is preferable that the floor material is a wooden floor material bonded to a floor heating panel.

  When the flooring material is bonded using the one-pack type room temperature moisture-curable adhesive composition for wood flooring of the present invention, the gap between the flooring materials can be reduced. Conventionally, in order to reduce the gap, it has been desirable to use an adhesive having a hardened product and a high adhesive strength. In the present invention, an alicyclic epoxy compound having one epoxy group in the molecule as the component (D) is used. This compound is a compound often used as a plasticizer, and is an adhesive composition. It is presumed that when such a compound is added to the product, the cured product becomes soft. However, it has been found that the use of (D) can reduce the gap, and the one-pack type room temperature moisture-curable adhesive composition for wood flooring of the present invention is a novel adhesive composition that reduces the gap. .

It is explanatory drawing of the measuring method of the magnitude | size of the space | gap of a flooring. It is explanatory drawing of the measuring method of tensile shear bond strength.

  Embodiments of the present invention will be described below, but these are exemplarily shown, and it goes without saying that various modifications are possible without departing from the technical idea of the present invention.

  The crosslinkable silicon group in the oxyalkylene polymer of the component (A) of the present invention is a group having a hydroxyl group or hydrolyzable group bonded to a silicon atom and capable of crosslinking by forming a siloxane bond. As a representative example, the formula (1):

(In the formula, R ¹ represents an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or R ² ₃ SiO— ^{(R 2} is an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms and the three ^{R 2} is And they may be the same or different when two or more R ¹ are present, and X is a hydroxyl group or A hydrolyzable group, when two or more X are present, they may be the same or different, a is 0, 1, 2 or 3, b is 0, 1 or 2; And n formulas (2):

におけるｂは同一である必要はない。ｎは０〜１９の整数を示す。但し、ａ＋（ｂの和）≧１を満足するものとする。）で表わされる基があげられる。

B in need not be the same. n shows the integer of 0-19. However, a + (sum of b) ≧ 1 is satisfied. ).

  The hydrolyzable group or hydroxyl group can be bonded to one silicon atom in the range of 1 to 3, and a + (sum of b) is preferably in the range of 1 to 5. When two or more hydrolyzable groups or hydroxyl groups are bonded to the crosslinkable silicon group, they may be the same or different.

The number of silicon atoms forming the crosslinkable silicon group may be one or two or more, but in the case of silicon atoms linked by a siloxane bond or the like, there may be about 20 silicon atoms.
Formula (3):

A crosslinkable silicon group represented by the formula (wherein R ¹ , X and a are the same as described above) is preferable from the viewpoint of easy availability. In the crosslinkable silicon group of the formula (3), a is preferably 2 or 3. When a is 3, the curing rate is higher than when a is 2.

Specific examples of R ¹ include an alkyl group such as a methyl group and an ethyl group, a cycloalkyl group such as a cyclohexyl group, an aryl group such as a phenyl group, an aralkyl group such as a benzyl group, and R ² ₃ SiO—. And triorganosiloxy group. Of these, a methyl group is preferred.

  It does not specifically limit as a hydrolysable group shown by said X, What is necessary is just a conventionally well-known hydrolysable group. Specific examples include a hydrogen atom, a halogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an acid amide group, an aminooxy group, a mercapto group, and an alkenyloxy group. Among these, a hydrogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an aminooxy group, a mercapto group, and an alkenyloxy group are preferable, and an alkoxy group, an amide group, and an aminooxy group are more preferable. An alkoxy group is particularly preferred from the viewpoint of mild hydrolysis and easy handling. Among the alkoxy groups, those having a smaller number of carbon atoms have higher reactivity, and the reactivity increases as the number of carbon atoms increases in the order of methoxy group> ethoxy group> propoxy group. Although it can be selected according to the purpose and application, a methoxy group or an ethoxy group is usually used. In the case of the crosslinkable silicon group represented by the formula (3), a is preferably 2 or more in consideration of curability.

Specific examples of the crosslinkable silicon group include trialkoxysilyl groups such as a trimethoxysilyl group and a triethoxysilyl group, dialkoxysilyl groups such as —Si (OR) ₃ , a methyldimethoxysilyl group, and a methyldiethoxysilyl group. Group, —SiR ₁ (OR) ₂ . Here, R is an alkyl group such as a methyl group or an ethyl group.

  Further, the crosslinkable silicon group may be used alone or in combination of two or more. The crosslinkable silicon group can be present in the main chain, the side chain, or both. It is preferable that a crosslinkable silicon group is present at the end of the molecular chain from the viewpoint of excellent cured product properties such as tensile properties of the cured product.

  In the oxyalkylene polymer of the component (A), the crosslinkable silicon groups should be present in an average of 1.0 to 5 and preferably 1.1 to 3 in one molecule of the polymer. When the number of crosslinkable silicon groups contained in the molecule is less than 1, the curability is insufficient, and when the number is too large, the network structure is too dense and may not exhibit good mechanical properties.

  The (A) component oxyalkylene polymer used in the present invention is essentially a polymer having a repeating unit represented by the formula (4).

（式中、Ｒ^３は２価の有機基）

(Wherein R ³ is a divalent organic group)

R ³ in Formula (4) is preferably a linear or branched alkylene group having 1 to 14 carbon atoms, and more preferably 2 to 4 carbon atoms. Specific examples of the repeating unit represented by the formula (4) include, for example,

Etc. The main chain skeleton of the oxyalkylene polymer may consist of only one type of repeating unit, or may consist of two or more types of repeating units. In particular, it is preferably made of a polymer mainly composed of oxypropylene.

  The number average molecular weight of the oxyalkylene polymer having a crosslinkable silicon group is preferably 3,000 to 50,000, and more preferably 5,000 to 20,000. In addition, the number average molecular weight as used in the field of this invention means the polystyrene conversion molecular weight by gel permeation chromatography. When the number average molecular weight is less than 3,000, the breaking strength may not be sufficient, and when it exceeds 50,000, the viscosity of the composition may increase and workability may decrease. The oxyalkylene polymer having a crosslinkable silicon group may be linear or branched.

  Examples of the method for synthesizing oxyalkylene polymers include polymerization methods using an alkali catalyst such as KOH, such as those disclosed in JP-A Nos. 61-197631, 61-215622, 61-215623, and 61-215623. Polymerization methods using organoaluminum-porphyrin complex catalysts obtained by reacting such organoaluminum compounds with porphyrins, such as double metal cyanide complex catalysts shown in, for example, JP-B-46-27250 and JP-B-59-15336 However, the polymerization method is not particularly limited. According to the polymerization method using an organoaluminum-porphyrin complex catalyst or the polymerization method using a double metal cyanide complex catalyst, the number average molecular weight is 6,000 or more, and the Mw / Mn is 1.6 or less. Coalescence can be obtained.

  The main chain skeleton of the oxyalkylene polymer may contain other components such as a urethane bond component. Examples of the urethane bond component include aromatic polyisocyanates such as toluene (tolylene) diisocyanate, diphenylmethane diisocyanate and xylylene diisocyanate; aliphatic polyisocyanates such as isophorone diisocyanate and hexamethylene diisocyanate and polyoxyalkylenes having a hydroxyl group; What can be obtained from this reaction can be mentioned.

  The introduction of a crosslinkable silicon group into an oxyalkylene polymer is reactive to this functional group in an oxyalkylene polymer having a functional group such as an unsaturated group, hydroxyl group, epoxy group or isocyanate group in the molecule. It can be performed by reacting a compound having a functional group having a crosslinkable silicon group. This method (hereinafter referred to as polymer reaction method) is preferably used for oxyalkylene polymers. This is because an oxyalkylene polymer usually has a hydroxyl group at the end of the molecular chain, so that it is easy to introduce a crosslinkable silicon group at the end.

  As a specific example of the polymer reaction method, a hydrosilane or mercapto compound is produced by reacting an unsaturated group-containing oxyalkylene polymer with a hydrosilane having a crosslinkable silicon group or a mercapto compound having a crosslinkable silicon group to form a crosslinkable silicon group. The method of obtaining the oxyalkylene type polymer which has can be mention | raise | lifted. An unsaturated group-containing oxyalkylene polymer is obtained by reacting an oxyalkylene polymer having a hydroxyl group with an organic compound having an active group and an unsaturated group that are reactive with the hydroxyl group, such as an unsaturated halogen compound. An oxyalkylene polymer containing an unsaturated group can be obtained.

  Other specific examples of the polymer reaction method include a method of reacting an oxyalkylene polymer having a hydroxyl group at a terminal with a compound having an isocyanate group and a crosslinkable silicon group, or an oxyalkylene polymer having an isocyanate group at a terminal. And a method of reacting a compound having an active hydrogen group such as a hydroxyl group or an amino group and a crosslinkable silicon group. When an isocyanate compound is used, an oxyalkylene polymer having a crosslinkable silicon group can be easily obtained.

  Specific examples of the oxyalkylene polymer having a crosslinkable silicon group include JP-B Nos. 45-36319 and 46-12154, JP-A Nos. 50-156599, 54-6096, and 55-13767. No. 57-164123, Japanese Patent Publication No. 3-2450, Japanese Patent Application Laid-Open No. 2005-213446, No. 2005-306891, International Publication No. WO 2007-040143, US Pat. Nos. 3,632,557, 4,345,053, The ones proposed in the publications such as 4,960,844 can be mentioned.

  A (meth) acrylic acid alkyl ester polymer having a crosslinkable silicon group can be added to the composition of the present invention in order to improve the durability of the cured product, the adhesion to the substrate or the chemical resistance. . The (meth) acrylic acid alkyl ester polymer having a crosslinkable silicon group is essentially a polymer having a repeating unit represented by the formula (5).

（式中、Ｒ^４は水素原子またはメチル基、Ｒ^５はアルキル基を示す）

(Wherein R ⁴ represents a hydrogen atom or a methyl group, and R ⁵ represents an alkyl group)

R ⁵ in Formula (5) is an alkyl group, and an alkyl group having 1 to 30 carbon atoms is preferable. R ⁵ may be linear or branched. Moreover, the substituted alkyl group which has a halogen atom, a phenyl group, etc. may be sufficient. Examples of R ⁵ include methyl group, ethyl group, propyl group, n-butyl group, t-butyl group, 2-ethylhexyl group, lauryl group, tridecyl group, cetyl group, stearyl group, and behenyl group. it can.

  The molecular chain of the (meth) acrylic acid alkyl ester polymer consists essentially of the monomer unit of the formula (5), and the term “essentially” as used herein means that of the formula (5) present in the polymer. It means that the total of monomer units exceeds 50% by mass. The total of the monomer units of the formula (5) is preferably 70% by mass or more.

  Examples of monomer units other than formula (5) include (meth) acrylic acid such as acrylic acid and methacrylic acid; amide groups such as acrylamide, methacrylamide, N-methylolacrylamide, and N-methylolmethacrylamide, glycidyl acrylate Monomers containing amino groups such as epoxy groups such as glycidyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, aminoethyl vinyl ether; other acrylonitrile, styrene, α-methylstyrene, alkyl vinyl ether, vinyl chloride, vinyl acetate, propionic acid Examples thereof include monomer units derived from vinyl, ethylene and the like.

  When a (meth) acrylic acid alkyl ester polymer having a crosslinkable silicon group is used in combination with an oxyalkylene polymer, the compatibility with the oxyalkylene polymer having a crosslinkable silicon group is great. A molecular chain having a crosslinkable silicon group has the following formula (6):

（式中、Ｒ^４は前記に同じ、Ｒ^６は炭素数１〜５のアルキル基を示す）で表される（メタ）アクリル酸エステル単量体単位と、下記式（７）：

(Wherein R ⁴ is the same as above, R ⁶ is an alkyl group having 1 to 5 carbon atoms) and a (meth) acrylate monomer unit represented by the following formula (7):

（式中、Ｒ^４は前記に同じ、Ｒ^７は炭素数６以上のアルキル基を示す）で表される（メタ）アクリル酸エステル単量体単位からなる共重合体が好ましい。

A copolymer composed of a (meth) acrylic acid ester monomer unit represented by the formula (wherein R ⁴ is the same as above, and R ⁷ is an alkyl group having 6 or more carbon atoms) is preferred.

As R < ⁶ > of the said Formula (6), C1-C5, such as a methyl group, an ethyl group, a propyl group, n-butyl group, t-butyl group, etc., Preferably it is 1-4, More preferably, it is 1-2. Of the alkyl group. Incidentally, R ⁶ may be a kind, or may be a mixture of two or more.

R ^{7 in the} above formula (7) is, for example, 2-ethylhexyl group, lauryl group, tridecyl group, cetyl group, stearyl group, behenyl group and the like having 6 or more carbon atoms, usually 7-30, preferably 8-20. Long chain alkyl groups. R ⁷ may be a single type or a mixture of two or more types. In addition, the mass ratio of the monomer unit of the formula (6) and the monomer unit of the formula (7) is preferably 95: 5 to 40:60, and more preferably 90:10 to 60:40.

  The (meth) acrylic acid alkyl ester polymer having a crosslinkable silicon group can usually be obtained by radical copolymerization of a (meth) acrylic acid alkyl ester and a (meth) acrylic acid alkyl ester having a crosslinkable silicon group. . Further, when an initiator having a crosslinkable silicon group or a chain transfer agent having a crosslinkable silicon group is used, the crosslinkable silicon group can be introduced into the molecular chain terminal.

  JP 2001-040037 A, JP 2003-048923 A and JP 2003-048924 A have a crosslinkable silicon group (meth) obtained by using a mercaptan having a crosslinkable silicon group and a metallocene compound. Acrylic acid alkyl ester polymers are described. Moreover, the synthesis example of Unexamined-Japanese-Patent No. 2005-026881 describes the (meth) acrylic-acid alkylester type polymer which has a crosslinkable silicon group by high temperature continuous polymerization.

  As disclosed in JP-A-2000-086999, a (meth) acrylic acid alkyl ester-based polymer having a crosslinkable silicon group, in which a crosslinkable silicon group is introduced at a high ratio at the molecular chain terminal, Are known. Since such a polymer is produced by living radical polymerization, a crosslinkable silicon group can be introduced into the molecular chain terminal at a high rate. In the present invention, a (meth) acrylic acid alkyl ester polymer as described above can be used.

  Specific examples of a (meth) acrylic acid ester-based polymer having a crosslinkable silicon group and a mixture of this polymer and an oxyalkylene polymer having a crosslinkable silicon group are disclosed in JP-A Nos. 59-122541 and 63-112642. And in each publication such as JP-A-6-172631. JP-A-59-78223, JP-A-59-168014, JP-A-60-228516, JP-A-60-228517, etc. disclose oxyalkylene polymers having a crosslinkable silicon group. (Meth) acrylic acid ester-based monomer is polymerized in the presence of a mixture of an oxyalkylene polymer having a crosslinkable silicon group and a (meth) acrylic acid alkyl ester polymer having a crosslinkable silicon group. The method of obtaining is described.

  When a mixture of an oxyalkylene polymer having a crosslinkable silicon group and a (meth) acrylic acid ester polymer having a crosslinkable silicon group is used, the (meth) acrylic acid is used with respect to 100 parts by mass of the oxyalkylene polymer. It is preferable to use 5-200 mass parts of ester polymers, and it is more preferable to use 5-50 mass parts.

  In addition to the oxyalkylene polymer having a crosslinkable silicon group, an organic polymer having a crosslinkable silicon group other than the (meth) acrylic acid ester polymer described above may be added to the adhesive composition of the present invention. Good. The main chain skeleton of the organic polymer having a crosslinkable silicon group to be used is not particularly limited, and those having various main chain skeletons can be used. Specifically, ethylene-propylene copolymers, polyisobutylene, copolymers of isobutylene and isoprene, polychloroprene, polyisoprene, isoprene or copolymers of butadiene and acrylonitrile and / or styrene, polybutadiene, Isoprene or a copolymer of butadiene and acrylonitrile, and / or styrene, etc., hydrocarbon polymers such as hydrogenated polyolefin polymers obtained by hydrogenating these polyolefin polymers; adipic acid, terephthalic acid, Polyester polymers such as condensation polymers of polybasic acids such as succinic acid and polyhydric alcohols such as bisphenol A, ethylene glycol and neopentyl glycol, and ring-opening polymers of lactones; by ring-opening polymerization of ε-caprolactam Nylon 6, hexamethyl By ring-opening polymerization of nylon 6,6 by condensation polymerization of diamine and adipic acid, nylon 6.10 by condensation polymerization of hexamethylenediamine and sebacic acid, nylon 11, by condensation polymerization of ε-aminoundecanoic acid, and ε-aminolaurolactam Polyamide polymer such as nylon 12, copolymer nylon having two or more components among the above nylons; polysulfide polymer; polycarbonate polymer produced by condensation polymerization of bisphenol A and carbonyl chloride, diallyl Examples thereof include phthalate polymers.

  In the present invention, a compound having a crosslinkable silicon group and an amino group or an imine derivative (aminosilanes) of this compound is used as the component (B). These act as adhesion-imparting agents. It also acts as a curing catalyst (silanol condensation catalyst) for component (A). The imine as used in the present invention refers to both aldimine and ketimine. As the crosslinkable silicon group in component (B), the same crosslinkable silicon group as in component (A) can be used. As the crosslinkable silicon group, an alkoxysilyl group in which the hydrolyzable group is an alkoxy group such as a methoxy group or an ethoxy group is preferable.

  Examples of the compound having a crosslinkable silicon group and amino group include γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropyltri Examples include methoxysilane, γ- (2-aminoethyl) aminopropyltriethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, and the like.

  The imine derivative can be obtained by ketiminizing the amino group of these compounds having a crosslinkable silicon group and amino group with a carbonyl compound. Examples of carbonyl compounds include aldehydes such as acetaldehyde, propionaldehyde, n-butyraldehyde, isobutyraldehyde, diethylacetaldehyde, glyoxal, and benzaldehyde; cyclic ketones such as cyclopentanone, trimethylcyclopentanone, cyclohexanone, and trimethylcyclohexanone; acetone, Aliphatic ketones such as methyl ethyl ketone, methyl propyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, diethyl ketone, dipropyl ketone, diisopropyl ketone, dibutyl ketone, diisobutyl ketone; acetylacetone, methyl acetoacetate, ethyl acetoacetate, dimethyl malonate, Β-dicarbonyl compounds such as diethyl malonate, methyl ethyl malonate, and dibenzoylylmethane And the like can be used. When an imino group (= NH group) is present in the imine derivative, the imino group may be reacted with styrene oxide; glycidyl ether such as butyl glycidyl ether or allyl glycidyl ether; glycidyl ester or the like. When an imine derivative is used as the component (B), it does not react with the epoxy compound of the component (D) during storage of the curable composition, so that a one-component curable composition can be obtained.

Component (B) is KBE-9103 (manufactured by Shin-Etsu Chemical Co., Ltd.), Sila Ace S340 (manufactured by Chisso Corporation), Z-6860 (manufactured by Toray Dow Corning Co., Ltd.), X-12-812H (Shin-Etsu Chemical Co., Ltd.) Etc.) and are commercially available.

  (B) The usage-amount of a component is 0.1-20 mass parts based on 100 mass parts of polymers of (A) component, Preferably it is 1-10 mass parts. Component (B) can be used in combination of two or more.

  In the present invention, (C) a tetravalent tin compound is used as the organotin silanol condensation catalyst. Although the component (B) also acts as a silanol condensation catalyst, the organotin silanol condensation catalyst is the main curing catalyst for the polymer of the component (A). For one-component adhesives (curable compositions), improving storage stability by using a tetravalent tin compound in which an organic group such as an alkyl group is bonded to a tin atom by a Sn-C bond Can do. Examples of tetravalent tin compounds include dibutyltin dilaurate, dibutyltin maleate, dibutyltin diacetate, dioctyltin dilaurate, dioctyltin maleate, dioctyltin diacetate, reaction products of dibutyltin salts and tetraethoxysilane. be able to. Component (C) is used in an amount of 0.1 to 10 parts by weight, preferably 0.2 to 7 parts by weight, per 100 parts by weight of component (A).

  Further, a silanol condensation catalyst other than the tetravalent tin compound may be used in combination. Examples of silanol condensation catalysts other than tetravalent tin compounds include other organic tin compounds such as divalent tin compounds, titanium compounds such as alkyl titanates and organosilicon titanates, bismuth tris 2-ethylhexo Examples thereof include bismuth compounds such as ate, tin salts of carboxylic acids such as tin octylate and tin naphthenate: amine salts such as dibutylamine-2-ethylhexoate.

  In the present invention, an alicyclic epoxy compound having one epoxy group in the molecule is used as the component (D). When the floor material is bonded using the curable adhesive composition for a wooden floor material of the present invention in which the component (D) is used, the space between the floor materials can be reduced. Examples of (D) are cyclohexane oxide, 4-vinylepoxycyclohexane, 3,4-epoxycyclohexylmethanol, 3,4-epoxycyclohexylmethyl methacrylate, epoxyhexahydrophthalic acid di-2-ethylhexyl,

And alicyclic epoxy compounds. The component (D) preferably has no crosslinkable silicon group in the molecule. The amount of the alicyclic epoxy compound having one epoxy group in the component (D) molecule is 0.1 to 100 parts by mass, preferably 1 to 50 parts per 100 parts by mass of the polymer (A). The range is 1 part by mass, more preferably 1-40 parts by mass, and particularly preferably 2-30 parts by mass.

  In the curable adhesive composition of the present invention, a plasticizer, a filler, a stabilizer, a dehydrating agent, an anti-sagging agent, an adhesion-imparting agent, a lubricant, a pigment, an epoxy resin, an epoxy resin curing agent, and the like are further included as necessary. Can be added.

  Specific examples of the plasticizer include phthalic acid esters such as dioctyl phthalate, dibutyl phthalate and butyl benzyl phthalate; aliphatic dibasic acid esters such as dioctyl adipate, isodecyl succinate and dibutyl sebacate; diethylene glycol dibenzoate, penta Glycol esters such as erythritol ester; aliphatic esters such as butyl oleate and methyl acetylricinoleate; phosphate esters such as tricresyl phosphate, trioctyl phosphate and octyl diphenyl phosphate; dibasic acid and dihydric alcohol Polyester plasticizers such as polyesters; Polyethers such as polypropylene glycol and its derivatives; Hydrocarbon plastics such as paraffinic hydrocarbons, naphthenic hydrocarbons, and paraffin-naphthene mixed hydrocarbons S; chlorinated paraffins; low molecular weight acrylic ester polymer and the like. These plasticizers may be used alone or in combination of two or more. In particular, when an acrylic ester polymer is used, the durability of the cured product can be improved.

  When using a plasticizer, it is good to use normally in the range of 10-200 mass parts with respect to 100 mass parts of (A) component, Preferably it is the range of 20-100 mass parts. If the amount of the plasticizer used is less than 10 parts by mass, the viscosity of the composition may be too high, and if it exceeds 200 parts by mass, the plasticizer may exude from the cured product. It is not preferable.

  Examples of fillers include reinforcing fillers such as fumed silica, precipitated silica, silicic anhydride and carbon black; calcium carbonate, magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, hardened titanium, bentonite, organic bentonite Further, fillers such as ferric oxide, zinc oxide and activated zinc white; hollow fillers such as glass balloons and shirasu balloons; fibrous fillers such as asbestos, glass fibers and filaments can be used.

  When it is desired to obtain a cured product having high strength by using these fillers, mainly fumed silica, precipitated silica, anhydrous silicic acid, hydrous silicic acid and carbon black, surface-treated fine calcium carbonate, calcined clay, clay, Preferred results are obtained by using fillers selected from activated zinc white and the like. In addition, when it is desired to obtain a cured product having low strength and large elongation, a filler selected from titanium oxide, calcium carbonate, magnesium carbonate, talc, ferric oxide, zinc oxide, shirasu balloon, etc. is mainly used. Preferred results are obtained when used. Of course, these fillers may be used alone or in combination of two or more.

  When using a filler, it is good to use in the range of 1-700 mass parts normally with respect to 100 mass parts of (A) component, Preferably it is the range of 5-500 mass parts, More preferably, it is 5-350 mass parts. .

  Examples of stabilizers include hindered phenols and hindered amines. When the hindered amine is contained in the adhesive composition of the present invention, the polyethylene hot water pipe and the adhesive composition come into contact with each other and the polyethylene deteriorates when used for bonding the flooring and the hot water floor heating panel. This can be prevented. Examples of hindered amines include dibutylamine, 1,3,5-triazine, N, N′-bis (2,2,6,6-tetramethyl-4-piperidyl-1,6-hexamethylenediamine and N- ( Polycondensates with 2,2,6,6-tetramethyl-4-piperidyl) butylamine, etc., poly [{6- (1,1,3,3-tetramethylbutyl) amino-1,3,5-triazine -2,4-diyl} {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene {(2,2,6,6-tetramethyl-4-piperidyl) imino}] succinic acid Examples include a polymer of dimethyl and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidineethanol, etc. When a stabilizer is used, 0.1 parts by weight per 100 parts by weight of component (A). In the range of -10 parts by mass It is good to use.

  Examples of dehydrating agents include silane compounds such as vinyltrimethoxysilane, dimethyldimethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, and diphenyldimethoxysilane. And hydrolysable ester compounds such as methyl orthoformate, ethyl orthoformate, methyl orthoacetate, ethyl orthoacetate and the like, and these can be used alone or in combination of two or more.

  Examples of the sagging inhibitor include hydrogenated castor oil, fatty acid bisamide, fumed silica and the like.

  Examples of the adhesion imparting agent include various silane coupling agents such as aminosilanes such as aminoethylaminopropyltrimethoxysilane, aminoethylaminopropylmethyldimethoxysilane, aminoethylaminopropylmethylmethoxysilane, and γ-glycidoxypropyltrimethoxy. Epoxy silanes such as silane, acrylic silanes such as γ-methacryloxypropyltrimethoxysilane, mercaptosilanes such as γ-mercaptopropyltrimethoxysilane, isocyanate silanes such as γ-isocyanatopropyltrimethoxysilane, etc. . The said adhesion grant agent may be used independently and may be used together 2 or more types.

  The adhesive composition of the present invention can be obtained by dispersing the material constituting the adhesive composition with a planetary mixer, three rolls, or the like, if necessary. The adhesive composition of the present invention is a one-component adhesive composition, and it is desirable to remove as much water as possible from the blended components and the composition. The adhesive composition of the present invention is room temperature moisture curable and can be cured with moisture at room temperature. However, the adhesive composition may be heated to accelerate curing as necessary.

  The curable adhesive composition of the present invention is used to bond a wooden flooring to a base material. Examples of the bonding method include a method of applying a bead shape at several places along the short side of the back surface of the flooring material and pressing it against the base material for curing. When the base material is a floor heating unit, the curable adhesive composition of the present invention can suitably bond the wooden floor material and the floor heating unit.

  The present invention will be described more specifically with reference to the following examples. However, it is needless to say that these examples are shown by way of illustration and should not be construed in a limited manner.

(Examples 1-2, Comparative Examples 1-3)
As the oxyalkylene polymer having a crosslinkable silicon group (A) shown in Table 1, commercially available polymers, fillers and plasticizers were charged in the proportions shown in Table 1, followed by heating and vacuum mixing and stirring at 110 ° C. The mixture was dehydrated for 2 hours. Furthermore, (B) component crosslinkable silicon group and amino group-containing compound or imine derivative, (C) component tetravalent tin compound, (D) component alicyclic having one epoxy group in the molecule A predetermined amount of an epoxy compound was added and mixed by stirring to prepare a curable adhesive composition. Using these curable adhesive compositions, storage stability, size of gap when used for flooring, shear bond strength after initial and thermal exposure, and dumbbells after initial and thermal exposure were used. Tensile properties (breaking strength, elongation at break) were measured. The results are shown in Table 1. In the table, CF indicates cohesive failure of the adhesive itself. Moreover, the evaluation method of characteristics is as described later.

In Table 1, the compounding quantity of each compounding substance is shown in parts by mass. Details of each compounding substance are as follows.
* 1: Kaneka Co., Ltd., crosslinkable silicon group-containing oxypropylene polymer * 2: Shin-Etsu Chemical Co., Ltd., N-2- (aminoethyl) -3-aminopropyltrimethoxysilane * 3: Shin-Etsu Chemical Industrial Co., Ltd., reaction product of MIBK (methyl isobutyl ketone) and 3-aminopropyltrimethoxysilane * 4: Nitto Kasei Co., Ltd., reaction product of dibutyltin salt and tetraethoxysilane * 5: Nitto Kasei Made by Co., Ltd., Stanas octoate * 6: Shin Nippon Rika Co., Ltd., epoxy 2-dihexylhexahydrophthalate * 7: Mitsubishi Chemical Co., Ltd., liquid epoxy resin, molecular weight 370, epoxy equivalent 184- 194 (g / eq)
* 8: Shiraishi Calcium Co., Ltd., heavy calcium carbonate * 9: Shiraishi Calcium Co., Ltd., fatty acid-treated colloidal calcium carbonate * 10: Sumitomo 3M Co., Ltd., glass micro hollow sphere * 11: Mitsui Chemicals, Inc. ), Polypropylene ether diol molecular weight 3000
* 12: Colcoat Co., tetraethoxysilane * 13: Adeka Co., Ltd., hindered phenol antioxidant

(Storage stability test)
Immediately after preparation of the adhesive composition (before storage), and after lapse of 7 days (after storage) under the condition of 50 ° C. in a closed container, the viscosity at 23 ° C. was measured, and the thickening rate was calculated. Moreover, the surface of the adhesive with which the polyethylene container was filled was confirmed by finger touch for the curability after curing for 16 hours at 23 ° C. and 50% RH before and after storage under the same conditions. If the adhesive did not adhere to the finger, it was cured, and if it adhered, it was uncured. Storage stability (thickening rate and curability) was evaluated according to the following evaluation criteria.
X: Thickening rate exceeds 2 times or uncured before or after storage, Δ: cured at both 2 to 1.5 times thickening rate and before and after storage, ○: thickening rate less than 1.5 times and Cured both before and after storage.

(Gap size when used for bonding flooring)
After applying the adhesive 14 at four locations in a bead shape having a width of 10 mm at intervals of about 300 mm in the short direction of the flooring material 10 (flooring material, Asahi Woodtech New Forte Floor length 910 mm × width 303 mm × thickness 12 mm) 1 and laminated on a base conifer plywood 18 (length 1820 mm × width 910 mm × thickness 28 mm) as shown in FIG. After fixing the male side of the flooring material with a floor tucker 12 (Max 38mm floor staple (438 floor)) at intervals of 300mm, it was cured at 23 ° C and 50% RH for one week, and the length in the longitudinal direction of the flooring material was calipered. Measured. After this test body was dried at 60 ° C. for 3 days, the length of the flooring material was measured in the same manner, and the shrinkage length (around 1820 mm) of the flooring material before and after drying at 60 ° C. for 3 days was calculated. The base softwood plywood was previously dried at 60 ° C. for one week so as not to shrink over time.

(Shear bond strength)
It measured according to the wood tension shear bond strength test method of JIS K6851 adhesive. A spacer 20 having a thickness of 0.5 mm as shown in FIG. 2 is fixed to the adhesive surface of the test piece (adhered body 18, rice bran length 70 mm × width 25 mm × thickness 5 mm), and then adhesive 14 is applied and pressed. did. The coating length and width were each 25 mm. After curing at 23 ° C. and 50% RH for 1 week, the tensile shear bond strength was measured at a test speed of 3 mm / min. In addition, it was visually confirmed whether the fracture state was adhesive fracture (CF), interface peeling (AF), or material (wood) fracture (MF). Further, as a heat exposure test, a test piece after curing for 1 week at 23 ° C. and 50% RH was further heated at 80 ° C. for 1 week, and then the tensile shear bond strength was measured in the same manner.

(Dumbell tensile properties)
An adhesive film having a thickness of 2 mm was formed on a release paper and cured for one week in an environment of 23 ° C. and 50% RH. A dumbbell-shaped No. 2 type test piece specified in JIS K6251 was prepared, a tensile test was performed at a test speed of 50 mm / min, and the breaking strength and elongation at break were measured. Further, as a heat exposure test, a test piece after curing for 1 week at 23 ° C. and 50% RH was further heated at 80 ° C. for 1 week, and then a tensile test was performed in the same manner to measure the breaking strength and elongation at break.

  As is clear from the comparison between Examples 1 and 2 and Comparative Example 1, the curable adhesive composition containing an alicyclic epoxy compound having one epoxy group in the molecule of component (D) is a flooring. It can be seen that the size of the gap when used in the case is small. In Example 1 and Comparative Example 1, the composition is almost the same, and the size of the gap is reduced despite the fact that there is not much difference in the properties of the cured product (dumbbell) of the adhesive itself and the shear adhesive strength. (D) It is thought that a component has a peculiar effect. Moreover, in Comparative Example 2 using a divalent tin compound instead of the component (C) as a catalyst and Comparative Example 3 using an epoxy resin instead of the component (D), the storage stability was poor.

  The curable adhesive composition of the present invention can reduce the gap when used for a wooden flooring, and is useful as an adhesive for a wooden flooring.

  10: flooring material, 12: floor tacker, 14: adhesive, 16: base softwood plywood, 18: adherend, 20: spacer.

Claims (3)

(A) 100 parts by mass of an oxyalkylene polymer having a hydroxyl group or a hydrolyzable group bonded to a silicon atom and having a silicon-containing group that can be crosslinked by forming a siloxane bond,
(B) A compound having a hydroxyl group or hydrolyzable group bonded to a silicon atom in the molecule and having a silicon-containing group and an amino group that can be crosslinked by forming a siloxane bond, or an imine derivative of the compound 0.1 to 0.1 20 parts by mass,
(C) 0.1 to 10 parts by mass of a tetravalent tin compound, and (D) 1 to 100 parts by mass of an alicyclic epoxy compound having one epoxy group in the molecule,
A one-component room temperature moisture curable adhesive composition for wood floors containing   2. The one-component room temperature moisture-curable adhesive composition for wood flooring according to claim 1, wherein the (C) tin compound is a dialkyl tin compound.   The one-pack type room temperature moisture-curable adhesive composition for a wooden floor material according to claim 1, wherein the floor material is a wooden floor material bonded to a floor heating panel.

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