JPWO1998030649A1 - Glass adhesive - Google Patents

Abstract

(57) [Abstract] The present invention provides the following adhesive, which has good adhesive durability between a resin composition containing butyl-based rubber and a glass plate. The present invention also provides the following adhesive, which is particularly suitable as an adhesive for bonding a resin composition containing butyl-based rubber to a glass plate in double-glazing using a spacer made of a resin composition containing butyl-based rubber. Specifically, the present invention is an adhesive for bonding a resin composition containing butyl-based rubber to inorganic glass, the adhesive comprising, as an active ingredient, at least one selected from the group consisting of (A) a mixture of a terminally reactive oligomer having a repeating unit of a divalent hydrocarbon group having four carbon atoms and a chain extender, (B) a reaction product of a terminally reactive oligomer having a repeating unit of a divalent hydrocarbon group having four carbon atoms and a chain extender, (C) a mixture of a polyester polyol and a polyisocyanate, and (D) a reaction product of a polyester polyol and a polyisocyanate.

Description

[Detailed Description of the Invention] Glass Adhesive Technical Field The present invention relates to an adhesive for bonding a resin composition containing a butyl rubber to inorganic glass (hereinafter simply referred to as glass unless otherwise specified), which is useful for vehicle applications and building component applications, and in particular to an adhesive used in the production of double-glazing.

BACKGROUND ART Butyl rubber is sometimes used to bond and secure glass to other building components or glass to glass in the vicinity of vehicle window glass or building materials. It is also sometimes used to seal gaps between glass and other building components or between glass panes, which require low moisture permeability. The reason butyl rubber is used for these applications is that it has strong adhesiveness, low moisture permeability, and high weather resistance.

However, the adhesiveness of butyl rubber is easily reduced when moisture or other substances penetrate the interface between the substrate and the butyl rubber. Furthermore, in compositions containing butyl rubber and various compounding agents, the adhesive strength of the butyl rubber is highly dependent on the physical properties of the composition. For example, increasing the hardness of the composition reduces its adhesiveness, making it difficult to ensure good adhesion to the substrate. Butyl rubber alone or compositions with similar physical properties tend to creep due to their low modulus of elasticity. However, compositions containing relatively large amounts of compounding agents have a high modulus of elasticity, making them less prone to creep, but they also suffer from reduced adhesiveness and insufficient adhesion to the substrate.

When butyl rubber is used as an edge sealant for double-glazed glass, a metal spacer such as aluminum is usually used due to its low hardness, and butyl rubber is placed between the spacer and the glass as a sealant. The butyl rubber seals the glass pane and the spacer surface, maintaining airtightness.

Figure 3 shows a cross-sectional view of the edge of the conventional double-glazed glass 1. Two glass panes 1a and 1b are opposed to each other via a metal spacer 2 containing a desiccant 6, forming a hollow layer 7. A primary sealant 3 made of butyl rubber is interposed between the glass panes 1a and 1b and the metal spacer 2 to insulate the hollow layer 7 from the outside air. Furthermore, the gap (recess) 8 formed between the inner peripheral edges of the opposing glass panes and the outer peripheral surface of the spacer is sealed with a secondary sealant 5 made of a room-temperature-curing sealant, typically a polysulfide-based or silicone-based sealant.

Conventional double-glazing systems use metal spacers, which complicates the manufacturing process. Therefore, there is a need for a structure that can simplify the manufacturing process. To date, various methods have been proposed to simplify or automate the double-glazing manufacturing process, including bending aluminum spacers and automating the application of room-temperature-curing sealants, thereby improving productivity and ultimately reducing costs.

However, regardless of the type of spacer used, double-glazed glass using these cold-setting sealants requires a long curing period after manufacturing to allow the sealant to harden. As a result, the product cannot be shipped until the curing period is complete. This requires setting up a curing space within the factory and storing the product for a certain period before shipping, lengthening delivery times and not always meeting customer needs. Furthermore, meeting future demand will require even more curing space. To avoid this and ensure a sufficient supply of double-glazed glass, it is considered necessary to shorten the curing time.

To reduce the cost of double-glazing glass, it has been proposed to use a molded product made from a partially vulcanized butyl rubber composition incorporating a desiccant as a spacer (Japanese Patent Publication No. 1981-20501). However, this butyl rubber-containing resin composition lacked hardness, making it difficult for the spacer alone to maintain its shape as a double-glazing glass unit. To solve this problem, adding a large amount of filler to the resin composition to increase its hardness would increase the stress at the interface with the glass, and the adhesive strength of the butyl rubber alone would be insufficient to provide durable adhesion.

Butyl rubber has high adhesive strength on its own, not just for double-glazing applications. However, when various additives are added to improve the physical properties of butyl rubber, the adhesive strength may be insufficient when the composition is bonded to glass. In such cases, it is desirable to employ a method to improve the adhesive strength, particularly the durable adhesive strength, between the composition and glass. However, methods for improving the adhesive strength between resin compositions containing butyl rubber and glass have not been thoroughly investigated.

DISCLOSURE OF THE INVENTION The present invention is as follows.

An adhesive for bonding a resin composition containing butyl rubber to inorganic glass, the adhesive comprising as an active ingredient at least one selected from the group consisting of: (A) a mixture of a terminally reactive oligomer having a divalent hydrocarbon group having four carbon atoms as a repeating unit and a chain extender; (B) a reaction product of a terminally reactive oligomer having a divalent hydrocarbon group having four carbon atoms as a repeating unit and a chain extender; (C) a mixture of a polyester polyol and a polyisocyanate; and (D) a reaction product of a polyester polyol and a polyisocyanate.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial cross-sectional view showing an example of the construction of double glazing.

FIG. 2 is a partial cross-sectional view showing another example of the structure of double glazing.

FIG. 3 is a partial cross-sectional view showing the structure of a conventional double glazing unit.

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors have investigated ways to solve the adhesion problem by bonding inorganic glass to a resin composition containing butyl rubber using an adhesive. Resin compositions containing butyl rubber have low moisture permeability and high weather resistance, making them particularly suitable as spacers for double glazing.

As a result of this investigation, the inventors have found an adhesive suitable for this purpose, which will now be described.

(Terminally Reactive Oligomer) In this invention, the terminally reactive oligomer having a repeating unit of a divalent hydrocarbon group having four carbon atoms is an oligomer containing repeating units derived from a hydrocarbon monomer having four carbon atoms, and is a compound having reactive functional groups such as hydroxyl, carboxyl, amino, mercapto, epoxy, or isocyanate groups at the oligomer terminals. By reacting this functional group with a chain extender having a functional group reactive with it to extend the chain or crosslink, the compound can become a high-molecular-weight polymer that functions as an adhesive.

The lower limit of the molecular weight of the terminally reactive oligomer is not particularly limited, but is typically 300. The upper limit is not particularly limited, but is typically about 100,000. The molecular weight is preferably 500 to 10,000, and particularly preferably 800 to 5,000. The terminally reactive oligomer is preferably a substantially linear oligomer. Furthermore, the relatively low molecular weight oligomer may be a branched oligomer, or may be a tri- or higher functional oligomer having branches each having a reactive functional group at each end.

The divalent hydrocarbon group having four carbon atoms as a repeating unit is preferably a repeating unit containing no unsaturated groups. Examples _of such saturated hydrocarbon groups include an ethylethylene group [ _-CH2- CH( _CH2CH3 )-], a 1,2-dimethylethylene group [-CH( _CH3 )-CH(CH3)-], a 1,1-dimethylethylene group [-C( _CH3 ) ₂ - _CH2- ], and a tetramethylene group [-( _CH2 ) _4- ]. These are units (ethylethylene and tetramethylene) formed by adding hydrogen to polymerized units of 1-butene, ₂ -butene, and isobutylene, respectively, and to polymerized units of butadiene.

The terminally reactive oligomer is an oligomer formed from one or more of these repeating units. In addition to these repeating units, it may also contain relatively small amounts of other repeating units. Examples of such other repeating units include polymerized units of dienes with 5 or more carbon atoms, such as isoprene, pentadiene, and dicyclopentadiene; polymerized units of halogen-containing dienes, such as chloroprene; and polymerized units of olefins, such as ethylene, propylene, and styrene. The proportion of other repeating units in the terminally reactive oligomer is preferably 20 mol % or less of the total repeating units. The other repeating units may contain unsaturated groups. They may also contain small amounts of unsaturated hydrocarbon groups with 4 carbon atoms.

Preferred reactive terminal oligomers in the present invention are 1-butene homopolymers, isobutylene homopolymers, copolymers of 1-butene and isobutylene, hydrogenated butadiene homopolymers (1,2-polybutadiene and 1,4-polybutadiene), and copolymers and hydrogenated copolymers of one or more C4 monomers such as 1-butene, isobutylene, and butadiene with isoprene, pentadiene, styrene, etc. The most preferred reactive terminal oligomers are hydrogenated butadiene homopolymers and isobutylene homopolymers.

The functional groups in the terminally reactive oligomer include hydroxyl groups, carboxyl groups, amino groups, mercapto groups, epoxy groups, isocyanate groups, etc. Hydroxyl groups and carboxyl groups are preferred, and hydroxyl groups are particularly preferred.

(Chain extender) A compound having two or more functional groups that can react with the functional groups of the reactive oligomer described above is used as the chain extender.

For example, hydroxyl-terminated oligomers can be reacted with chain extenders such as polyisocyanates to form polyurethanes, or with chain extenders such as polycarboxylic acids or their acid chlorides or alkyl esters to form polyesters. Similarly, carboxyl-terminated oligomers can be reacted with chain extenders such as polyols, polyamines, and polyepoxides, and amino-terminated oligomers can be reacted with chain extenders such as polyepoxides, polycarboxylic acids, and their anhydrides.

A particularly preferred combination of a terminally reactive oligomer and a chain extender in the present invention is a combination of a hydroxyl-terminated oligomer and a chain extender comprising a polyisocyanate or a polycarboxylic acid or a reactive acid derivative thereof.

(Polyisocyanate) The polyisocyanate used as a chain extender in this invention refers to an organic compound containing an average of two or more isocyanate groups per molecule. Polyisocyanates include monomeric polyisocyanates, their polymers, modified products, and isocyanate-terminated prepolymers. In this invention, one or more of these may be used. Examples of monomeric polyisocyanates include the following polyisocyanates:

Aromatic polyisocyanates such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, tolidine diisocyanate, 1,5-naphthalene diisocyanate, triphenylmethane triisocyanate, tris(isocyanatophenyl)thiophosphate, xylene diisocyanate, and tetramethylxylene diisocyanate. Aliphatic polyisocyanates such as ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, lysine ester diisocyanate, trimethylhexamethylene diisocyanate, 1,3,6-hexamethylene triisocyanate, and 1,6,11-undecane triisocyanate. Alicyclic polyisocyanates such as isophorone diisocyanate, transcyclohexane diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, dicyclohexylmethane-1,4-diisocyanate, 1-methyl-2,5-diisocyanatocyclohexane, and 1-methyl-2,6-diisocyanatocyclohexane.

Examples of the above-mentioned monomeric polyisocyanate multimers, modified products, and isocyanate-terminated polymers include urethane-modified products obtained by reacting with polyols, isocyanate-terminated urethane prepolymers, dimers, trimers, carbodiimide-modified products, urea-modified products, and biuret-modified products. In particular, urethane-modified products modified with trimethylolpropane and isocyanurate trimers are preferred. In some cases, blocked polyisocyanates obtained by blocking isocyanate groups with a blocking agent can also be used.

Aromatic polyisocyanates (which may be non-yellowing aromatic polyisocyanates such as xylene diisocyanate) are preferred to hasten the development of initial adhesive strength, while aliphatic or alicyclic polyisocyanates are preferred to improve compatibility with butyl rubber-containing resin compositions and enhance adhesive strength.

(Polycarboxylic Acid or Reactive Acid Derivative thereof) The polycarboxylic acid or reactive acid derivative thereof used as a chain extender in the present invention is preferably a dicarboxylic acid or reactive acid derivative thereof, and in some cases, a small amount of a tri- or higher functional polycarboxylic acid or its reactive acid derivative may also be used in combination.

The dicarboxylic acid may be an aliphatic dicarboxylic acid, an alicyclic dicarboxylic acid, an aromatic dicarboxylic acid, or the like, and two or more of these may be used in combination. Aliphatic dicarboxylic acids are particularly preferred.

As reactive acid derivatives of dicarboxylic acids, acid chlorides, lower alkyl esters such as methyl esters, and acid anhydrides are preferred, with acid chlorides being particularly preferred.

The molecular weight of these dicarboxylic acids and their reactive acid derivatives is not particularly limited, but a molecular weight of 300 or less is preferred.

Specific examples of dicarboxylic acids include the following: aliphatic dicarboxylic acids such as adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, malonic acid, succinic acid, and glutaric acid; alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid; and aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, toluenedicarboxylic acid, and naphthalenedicarboxylic acid.

(Adhesives Composed of a Combination of Hydroxyl-Terminated Oligomers and Polyisocyanates) When combining hydroxyl-terminated oligomers and polyisocyanates, their mixtures, as well as their reaction products, prepolymers and polyurethane polymers, can function as adhesives. Prepolymers include hydroxyl-terminated prepolymers and isocyanate-terminated prepolymers, with isocyanate-terminated prepolymers being particularly preferred.

When a polyurethane polymer is used as an adhesive, a diisocyanate is preferred as the polyisocyanate. When a mixture or prepolymer of a hydroxyl-terminated oligomer and a polyisocyanate is used, a diisocyanate, a tri- or higher functional polyisocyanate, or a combination of these is preferred.

The amount of polyisocyanate used is not particularly limited, but from the viewpoint of imparting curability, it is desirable to use a ratio of 0.6 to 10 equivalents, and particularly 0.8 to 5 equivalents, of isocyanate groups relative to the functional groups (e.g., hydroxyl groups) of the terminally reactive oligomer that can react with the isocyanate groups. Furthermore, because polyisocyanate can also be used as a crosslinking agent for polymers, even larger amounts of polyisocyanate can be used in the production stage of polymers or prepolymers. In such cases, for example, a ratio of 1 to 60 equivalents, and particularly 5 to 30 equivalents, of isocyanate groups relative to the functional groups of the oligomer can be used.

These adhesives can be used by dissolving them in a solvent, and polyurethane polymers with relatively low melting points can be used as so-called hot melt adhesives.

Furthermore, isocyanate-terminated prepolymers can be used in combination with chain extenders such as polyols, and hydroxyl-terminated prepolymers can be used in combination with chain extenders such as polyisocyanates. Furthermore, when using polyurethane polymers, they can also be used as adhesives by mixing them with chain extenders such as polyisocyanates (usually called crosslinkers).

When polyisocyanate is added after the polymer or prepolymer is produced, the amount of polyisocyanate used is preferably about 1 to 50 parts by weight per 100 parts by weight of the polymer or prepolymer.

(Adhesives Composed of a Combination of Hydroxyl-Terminated Oligomers and Polycarboxylic Acids or Their Reactive Acid Derivatives) When a hydroxyl-terminated oligomer is combined with a polycarboxylic acid or its reactive acid derivatives, the mixture of the two and the polyester reaction product thereof can function as an adhesive.

When a combination of a hydroxyl-terminated oligomer and a polycarboxylic acid or its reactive acid derivative is used, the two are usually reacted first to form a polymer, which is then used as an adhesive. This polymer is considered a type of polyester, and the polyester may have terminal hydroxyl or carboxyl groups. This polyester is obtained by reacting approximately equal amounts of a hydroxyl-terminated oligomer with a polycarboxylic acid or its reactive acid derivative.

Its molecular weight is preferably at least two times, and particularly at least five times, that of the hydroxyl-terminated oligomer. The resulting polyester is preferably a polyester that is solid at room temperature and can be melted by heating. Such adhesives can be used by dissolving them in a solvent. They can also be used as so-called hot-melt adhesives. The polyester can also be used by mixing it with a crosslinking agent such as polyisocyanate. In this case, it is preferable to use about 1 to 50 parts by weight of polyisocyanate per 100 parts by weight of polyester.

(Polyester Polyol) In the present invention, polyester polyol refers to a polyester having terminal hydroxyl groups obtained by the polycondensation reaction of a polycarboxylic acid or its reactive acid derivative with a polyol, the polycondensation reaction of an oxyacid, or the ring-opening polymerization reaction of a cyclic ester. In particular, polyester polyols obtained by the polycondensation reaction of a polycarboxylic acid or its reactive acid derivative with a polyol are preferred. While polyester polyols may be polymers with a small number of branches, linear polymers are preferred. In other words, polyester polyols obtained from dicarboxylic acids or their reactive acid derivatives with diols are preferred.

The lower limit of the molecular weight is not particularly limited, but 1,000, particularly about 5,000, is preferred.

There is no upper limit to the molecular weight as long as the polymer is heat-meltable, but a molecular weight of about 100,000, and particularly about 50,000, is preferred. Furthermore, considering ease of use as an adhesive in the manufacture of insulating glass, polyester polyols that are solid at room temperature are preferred. In other words, solid polyester polyols that can be used as so-called hot-melt adhesives are preferred.

For polyester polyols that are solid at room temperature, it is preferred that at least a portion of the polycarboxylic acid residues (the radicals remaining after removing the hydroxyl groups from the carboxyl groups in a polycarboxylic acid), which are one of the structural units of the polyester, be residues of aromatic polycarboxylic acids, particularly aromatic dicarboxylic acids. It is particularly preferred that 60 to 100 mol % of all polycarboxylic acid residues be residues of aromatic dicarboxylic acids. A portion of the polycarboxylic acid residues may also be residues of tri- or higher functional polycarboxylic acids, such as tricarboxylic acids.

Examples of aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, phthalic acid, toluenedicarboxylic acid, and naphthalenedicarboxylic acid, with terephthalic acid and isophthalic acid being particularly preferred. Examples of polycarboxylic acids other than aromatic polycarboxylic acids include aliphatic dicarboxylic acids such as adipic acid, suberic acid, and sebacic acid, and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. While the molecular weight of these polycarboxylic acids is not particularly limited, it is preferably less than 300, and more preferably 250 or less.

As the reactive acid derivative of polycarboxylic acid, its acid chloride, lower alkyl ester such as methyl ester, and acid anhydride are preferred, and acid chloride is particularly preferred.

Two or more of these polycarboxylic acids or reactive acid derivatives thereof may be used in combination.

The polyol residue (a group formed by removing the hydrogen atom from a hydroxyl group in a polyol), which is another structural unit of the polyester polyol, is preferably a residue derived from an aliphatic diol. Residues derived from aromatic diols or alicyclic diols may also be included in combination with the aliphatic diol. Furthermore, a portion of the polyol residue may be a residue of a polyol having three or more functionalities, such as a triol. The molecular weight of these polyols is not particularly limited, but is preferably less than 300, and more preferably 200 or less.

Examples of diols include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, and cyclohexanedimethanol, with neopentyl glycol and 1,4-butanediol being particularly preferred.

(Adhesives Composed of a Combination of Polyester Polyol and Polyisocyanate) When a combination of polyester polyol and polyisocyanate is used, the mixture of polyester polyol and polyisocyanate, as well as the prepolymer or polyurethane polymer that is the reaction product of the two, can function as an adhesive.

As the polyisocyanate, the above-mentioned polyisocyanates that can be used as chain extenders can be used. Diisocyanates, tri- or higher-functional polyisocyanates, or combinations thereof are preferred.

The amount of polyisocyanate used in this case is not particularly limited, but is usually at least equivalent to the polyester polyol, and an excess equivalent is preferred from the viewpoint of imparting curability. That is, it is desirable to use 1 to 60 equivalents, and particularly 5 to 30 equivalents, relative to the hydroxyl groups of the polyester polyol. Furthermore, in terms of weight ratio, the polyisocyanate can be used in an amount of about 50 parts by weight or less per 100 parts by weight of the polyester polyol.

These adhesives can be used by dissolving them in a solvent. Polymers with relatively low melting points can be used as hot-melt adhesives. Furthermore, isocyanate-terminated prepolymers can be used by mixing them with chain extenders such as polyols, and hydroxyl-terminated prepolymers can be used by mixing them with chain extenders such as polyisocyanates. Furthermore, when using polyurethane polymers, they can also be used as adhesives by mixing them with chain extenders such as polyisocyanates (usually called crosslinkers).

(Adhesive) When using a mixture of the above-mentioned terminally reactive oligomer and chain extender or a mixture of polyester polyol and polyisocyanate, the adhesive of the present invention is typically mixed and applied to the bonded portion of the butyl-based rubber-containing resin composition or inorganic glass before the two are fully reacted, by coating or otherwise applying the mixture. The two materials are then brought into contact and bonded. When using a prepolymer, it is used in the same manner, or a mixture of the prepolymer and chain extender is used. When using a polymer, it is typically applied to the bonded portion in the same manner as a hot-melt adhesive. When using these adhesives, it is preferable to dissolve them in a non-reactive solvent. In this case, the solution is applied to the bonded portion, and the solvent is then removed before use.

The adhesive of the present invention may be blended with additives such as solvents, catalysts, pigments, fillers, antioxidants, heat stabilizers, and antioxidants, as needed. As mentioned above, solvents are commonly used. Furthermore, blending a silane coupling agent is particularly preferred to improve adhesion. The amount of silane coupling agent blended is preferably 0.05 to 15 parts by weight, and more preferably 1 to 10 parts by weight, per 100 parts by weight of the components functioning as the adhesive.

The amount of components that function as an adhesive refers to the total amount of the terminally reactive oligomer, the chain extender, and their reaction products, or the total amount of the polyester polyol, the polyisocyanate, and their reaction products.

(Silane Coupling Agent) In the present invention, the adhesive may contain a silane coupling agent. Silane coupling agents refer to silane compounds in which an organic group having a hydrolyzable group and a functional group is bonded to a silicon atom, as well as their partial hydrolyzates and partial hydrolyzed condensates. Examples of hydrolyzable groups include residues obtained by removing the hydrogen atom from the hydroxyl group of hydroxyl-containing compounds, such as alkoxy groups, acyloxy groups, halogen atoms such as chlorine atoms, ketoximate groups, amino groups, aminooxy groups, amide groups, and isocyanate groups. Alkoxy groups with four or fewer carbon atoms are particularly preferred as hydrolyzable groups.

It is preferred that 1 to 3, and particularly 2 to 3, of these hydrolyzable groups be bonded to one silicon atom.

One silicon atom to which a hydrolyzable group is bonded has 1 to 3, preferably 1 to 2, organic groups (non-hydrolyzable organic groups bonded to the silicon atom via a carbon atom).

At least one, and preferably only one, of the organic groups is a functionalized organic group.

The other organic group is an organic group that does not have a functional group such as an alkyl group, and the organic group is preferably an alkyl group having 4 or fewer carbon atoms, such as a methyl group. These organic groups are typically monovalent organic groups, but may also be polyvalent organic groups, such as a divalent organic group linking two silicon atoms. Furthermore, this polyvalent organic group may also be an organic group that has a functional group. Silane coupling agents having monovalent organic groups containing functional groups will be further described below.

The functional group in the functional organic group includes an epoxy group, an amino group, a mercapto group, an unsaturated group, a chlorine atom, a carboxyl group, etc., with the epoxy group, the amino group, and the mercapto group being preferred. Specific examples include a 3-glycidoxypropyl group, a 2-(3,4-epoxycyclohexyl)ethyl group, a 3-aminopropyl group, an N-(2-aminoethyl)-3-aminopropyl group, a 3-(N-phenylamino)propyl group, a 3-mercaptopropyl group, a vinyl group, a 3-methacryloyloxypropyl group, a 3-(2-butenoyl)propyl group, and a 2-(4-vinylphenyl)ethyl group.

Preferred silane coupling agents for use in the present invention include, for example, the following silane coupling agents:

3-glycidoxypropyltrimethoxysilane, bis(3-glycidoxypropyl)dimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyldimethoxymethylsilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-(N-phenylamino)propyltrimethoxysilane, 3-(N-allylamino)propyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, 3-methacryloyloxypropyltrimethoxysilane, 3-chloropropyltrimethoxysilane.

(Glass) In this invention, glass generally refers to glass sheets, tempered glass sheets, laminated glass sheets, metal-wire glass sheets, heat-absorbing glass sheets, and glass sheets with a thin coating of metal or other inorganic material on the inner surface, such as heat-reflecting glass sheets and low-reflecting glass sheets, which are widely used in window materials for buildings and vehicles. Double-glazed glass refers to an assembly of the above structure, in which two or more sheets of such glass are combined to form a hollow space between them. In double-glazed glass, one of the two sheets forming the hollow space does not necessarily have to be inorganic glass; it can also be organic glass such as acrylic resin or polycarbonate resin.

(Butyl-Rubber-Containing Resin Composition) In this invention, a butyl-rubber-containing resin composition refers to a resin composition in which various compounding agents are added to butyl rubber to improve its physical properties. In particular, this invention is preferably applied to a butyl-rubber-containing resin composition used in double-glazing structures in which a metal spacer is not used and the butyl-rubber-containing resin composition itself functions as a spacer. Such a butyl-rubber-containing resin composition is a butyl-rubber-containing resin composition that incorporates a desiccant and various fillers into butyl rubber, resulting in a higher hardness than butyl rubber alone. Even more preferred is a high-hardness butyl-rubber-containing resin composition used in double-glazing structures that do not substantially require a secondary sealant.

Figures 1 and 2 show cross-sectional views of the edges of the above-mentioned double-glazing glass. Figure 1 shows a double-glazing glass 1 with a structure that uses a secondary sealant, in which two glass panes 1a and 1b are sealed with a resin spacer 4 made of a butyl-based rubber-containing resin composition and a secondary sealant 5 made of a room-temperature curing sealant. Figure 2 shows a double-glazing glass 10 without a secondary sealant, in which two glass panes 1a and 1b are sealed only with a spacer 20 made of a butyl-based rubber-containing resin composition. The adhesive of the present invention is most suitable as an adhesive for bonding the spacer made of a butyl-based rubber-containing resin composition and the glass panes 1a and 1b in double-glazing glass 1 and 10 with these structures.

Although spacers made from the above-described high-hardness butyl-based rubber-containing resin composition adhere to glass at high temperatures, the increased strength of the spacer itself tends to concentrate stress at the glass interface when subjected to tensile stress, leading to delamination. Therefore, an adhesive is considered necessary. In the manufacture of double-glazed glass, an adhesive is applied to cleaned glass and dried to form an adhesive layer on the glass surface. The spacer is then molded at high temperature and immediately adhered to the adhesive layer on the glass surface, or the spacer is placed on the adhesive layer on the glass surface and pressed at high temperature. In this process, if the adhesive has high adhesion after application, handling the glass after application can be difficult. Furthermore, if the adhesive does not develop adhesion immediately after molding, handling the double-glazed glass can be difficult. Therefore, to avoid these limitations, it is desirable to use a hot-melt adhesive among the adhesives of the present invention.

The butyl rubber in the butyl-rubber-containing resin composition of the present invention refers to isobutylene homopolymers, copolymers with other monomers, and modified products thereof. Homopolymers include relatively high-molecular-weight homopolymers and relatively low-molecular-weight homopolymers. The molecular weight of the former is typically 30,000 or higher, with typical examples (commercially available products) ranging from 50,000 to 150,000. The molecular weight of the latter is typically less than 30,000, with typical examples (commercially available products) ranging from 10,000 to 15,000. Note that molecular weight here refers to the viscosity-average molecular weight (Staudinger molecular weight). When using isobutylene homopolymers as the butyl rubber in the present invention, relatively high-molecular-weight homopolymers are used. Relatively low-molecular-weight homopolymers can be used in combination with other butyl rubbers and are typically used as additives for the purposes of imparting tack or plasticizing (lowering viscosity). Note that polyisobutylene in the examples refers to these isobutylene homopolymers.

Copolymers are polymers obtained by copolymerizing isobutylene with a relatively small amount of one or more copolymerizable monomers, such as isoprene, 1-butene, divinylbenzene, and p-methylstyrene. Copolymers obtained by copolymerization with isoprene (commonly known as butyl rubber) are particularly preferred. Modified butyl rubbers include halogenated butyl rubbers, such as chlorinated and brominated butyl rubbers, and partially vulcanized butyl rubbers obtained by partially vulcanizing butyl rubber. Particularly preferred butyl rubbers in the present invention are relatively high-molecular-weight isobutylene homopolymers, copolymers of isobutylene and isoprene, commonly known as butyl rubber, and partially vulcanized butyl rubber.

A preferred example of a high-hardness butyl-rubber-containing resin composition is a composition in which butyl rubber is blended with crystalline polyolefin. Crystalline polyolefin refers to a homopolymer of an olefin such as ethylene or propylene, a copolymer with other monomers, or a modified product thereof, which has crystallinity. The polymer structure is preferably a syndiotactic or isotactic structure, but may contain other structures. Ethylene and propylene are particularly preferred olefins.

Copolymers include copolymers of two or more olefins and copolymers of olefins with other monomers. Copolymers of ethylene or propylene with other monomers that do not inhibit crystallinity are suitable. Furthermore, block copolymers are more suitable than alternating or random copolymers. Modified polyolefins include crystalline polyolefins with functional groups such as acid anhydride, carboxyl, and epoxy groups.

Particularly preferred crystalline polyolefins are polyethylene and polypropylene, which are essentially homopolymers. For example, low-density polyethylene, medium-density polyethylene, high-density polyethylene, etc. can be used as the polyethylene. The crystallinity of the crystalline polyolefin is preferably 30% or more, and more preferably 50% or more. For example, typical crystallinity values for conventional crystalline polyolefins are 50-60% for low-density polyethylene, 75-90% for high-density polyethylene, and 55-65% for polypropylene. There are no particular restrictions on molecular weight, but a number-average molecular weight of approximately 200,000-800,000 is appropriate for polyethylene, and approximately 100,000-400,000 for polypropylene.

As such, polyethylene and polypropylene have high crystallinity and therefore lower moisture permeability than butyl rubber. In particular, polyethylene and polypropylene, which exhibit lower melt viscosities, can be blended with butyl rubber to reduce the melt viscosity of the composition and improve moldability compared to butyl rubber alone. This also makes it possible to blend various inorganic fillers, resulting in higher hardness butyl rubber-containing resin compositions. Furthermore, blending these materials is particularly desirable from an economical standpoint.

In the butyl-rubber-containing resin composition of the present invention, the proportion of crystalline polyolefin relative to the total amount of butyl rubber and crystalline polyolefin is preferably 2 to 50% by weight, and particularly preferably 5 to 40% by weight. If the proportion of crystalline polyolefin is less than 2% by weight, it is difficult to achieve high hardness for the butyl rubber. If the proportion exceeds 50% by weight, the properties of the crystalline polyolefin will dominate, making it difficult to exhibit the characteristics of the butyl rubber.

When an inorganic filler is compounded, the ratio of crystalline polyolefin to the total amount of butyl rubber and crystalline polyolefin can be small. For example, when approximately 50 parts by weight or more of inorganic filler is compounded to 100 parts by weight of butyl rubber and crystalline polyolefin, the ratio of crystalline polyolefin to the total amount of butyl rubber and crystalline polyolefin of 2 to 20% by weight will be sufficient to achieve the desired effect.

A substantially effective amount of inorganic filler can be blended into a butyl-based rubber-containing resin composition containing butyl-based rubber and crystalline polyolefin. A substantially effective amount refers to 1 part by weight or more per 100 parts by weight of the total of butyl-based rubber and crystalline polyolefin. Blending too much inorganic filler increases the melt viscosity of the composition and reduces its tensile strength and tear strength. Therefore, the upper limit of the blending amount is 200 parts by weight, and preferably 150 parts by weight. When blending inorganic filler, the preferred lower limit is 10 parts by weight.

As inorganic fillers, calcium carbonate, talc, mica, carbon black, and other commonly used inorganic fillers can be used alone or in combination.

It is extremely effective that the butyl rubber and crystalline polyolefin contained in the butyl-rubber-containing resin composition of the present invention are mixed at high temperatures, at least before the composition is used in its final application. "High temperatures" in this mixing refers to temperatures above the crystalline melting point of the crystalline polyolefin. This mixing temperature must be below the decomposition point of the butyl rubber, and is preferably below approximately 300°C, the decomposition point of typical butyl rubbers. From the standpoint of productivity, a temperature below 200°C is particularly preferred. Therefore, the crystalline melting point of the crystalline polyolefin is also preferably below 200°C.

It is preferable that the butyl-rubber-containing resin composition exhibit as little change in hardness as possible within its operating temperature range. To satisfy this requirement, a crystalline polyolefin with a crystalline melting point above the upper limit of normal operating temperature is preferred. The upper limit of normal operating temperature for double-glazed glass is approximately 80°C.

In the butyl-based rubber-containing resin composition described above, the crystalline polyolefin is restrained by the cohesive force of the crystalline phase. Therefore, even in the temperature range above the glass transition temperature, the sudden decrease in hardness and flow observed in amorphous resins do not occur below the crystalline melting point. Conversely, a significant decrease in melt viscosity is observed above the crystalline melting point, which is expected to improve blendability with butyl-based rubber.

Butyl-based rubber-containing resin compositions can further contain additives commonly used in sealants and the like. Examples of such additives include desiccants, lubricants, pigments, antistatic agents, tackifiers, plasticizers, antioxidants, heat stabilizers, antioxidants, hydrolyzable silyl group-containing compounds such as the silane coupling agents described above, foaming agents, and fillers other than the inorganic fillers described above. The incorporation of desiccants such as zeolite, silica gel, and alumina, tackifiers, plasticizers, silane coupling agents, and various stabilizers is particularly preferred.

Among the additives, it is particularly preferred to incorporate a desiccant such as zeolite in an amount of 5 to 30% by weight into the butyl-rubber-containing resin composition. It is also preferred to incorporate the aforementioned relatively low-molecular-weight polyisobutylene, an additive that provides tackifying and plasticizing effects, in an amount of up to 200 parts by weight, particularly 5 to 150 parts by weight, per 100 parts by weight of butyl-rubber.

The butyl-rubber-containing resin composition is preferably produced by mixing at least the butyl rubber and the crystalline polyolefin at a temperature above the crystalline melting point of the crystalline polyolefin and below the decomposition point of the butyl rubber. The mixing temperature is preferably 100 to 280°C, particularly 120 to 250°C. Other compounds and additives may be mixed simultaneously, before, or after the mixing. Such a resin composition is substantially a thermoplastic resin composition and can be mixed using a conventional mixer such as a melt-mixing extruder or kneader.

Because the butyl-based rubber-containing resin composition described above is essentially a thermoplastic resin composition, molding can be performed consecutively with the mixing process. Alternatively, the resin composition can be produced as a molding material, such as pellets, and then molded. Molding methods such as extrusion and injection molding can be used as molding methods. Alternatively, a double-glazing unit can be produced consecutively with the molding process by placing the molded product on the edge of a double-glazing unit consisting of two or more glass panes arranged opposite each other and coated with adhesive. In this case, the hot molded product discharged from the molding machine ensures high adhesion to the adhesive-coated glass panes. Alternatively, the molded product can be applied to the double-glazing unit while suppressing temperature drop using an applicator or other device. A heatable device is preferred.

As for the physical properties of the butyl-based rubber-containing resin composition used in double-glazing applications, it is preferable that the water vapor transmission coefficient according to JIS K7149 is 4.0×10 ⁻⁷ [cm ³ ·cm/(cm ² ·sec ·cmHg)] or less, particularly 7.0×10 ⁻⁸ [cm ³ ·cm/(cm ² ·sec ·cmHg)] or less. Furthermore, the JIS A hardness (HsA) at 25°C is preferably 5 or more, particularly 20 or more, from the viewpoint of the shape retention of the double-glazing. Furthermore, if the hardness is too high, there is a risk of increased stress being applied to the seals and glass panes of the double-glazing, so the upper limit of the hardness is preferably around 90. Incidentally, the HsA of butyl-based rubber alone is usually substantially 0.

In the present invention, the butyl-based rubber-containing resin composition is particularly excellent for sealing the edges of double-glazing. This double-glazing is preferably a double-glazing structure in which the glass panes are held together by the hardness of the butyl-based rubber-containing resin composition, without using a hard spacer such as a metal spacer, as described above. This butyl-based rubber-containing resin composition can be made into a resin composition of appropriate hardness by changing the amount of crystalline polyolefin or inorganic filler added, making it suitable as a spacer and sealing material for double-glazing structures that do not use metal spacers. It is particularly preferred that the butyl-based rubber-containing resin composition used for this purpose has a JIS A hardness (HsA) of 40 to 90 at 25°C. EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

(Example 1) (Adhesive Preparation) 50 g of 1,2-polybutadiene hydride (hydroxyl-terminated, hydroxyl value 50.8 mg KOH/g) was heated to 80°C and stirred. 4.78 g of isophorone diisocyanate was slowly added dropwise. The mixture was heated and stirred for 2 hours, and then heated and stirred at 120°C for 20 hours. After cooling, 200 g of a solvent consisting of an equal weight mixture of toluene and methyl ethyl ketone (MEK) was added and dissolved, yielding a solution with a solids concentration of approximately 20% by weight. This adhesive solution will be referred to as Solution A.

(Example 2) (Adhesive Manufacturing) 50 g of the same 1,2-polybutadiene hydride as in Example 1 was dissolved in dehydrated tetrahydrofuran (THF), 3.94 g of adipic acid dichloride was added, and the pressure was reduced to approximately 1 mmHg while stirring. The reaction mixture was heated to 65-70°C, stirred, and the THF was evaporated to obtain a reaction mixture. 0.01 g of titanium tetra-n-butoxide was added to the reaction mixture, and the reaction mixture was allowed to react at 180°C for 3 hours while the pressure was reduced to below 1 mmHg. After cooling, the mixture was dissolved in 200 g of a solvent consisting of an equal weight mixture of toluene and MEK, obtaining a solution with a solids concentration of approximately 20% by weight (hereinafter referred to as Solution B).

(Example 3) (Adhesive Production) 50 g of hydroxyl-terminated polyisobutylene (hydroxyl value 30.6 mg KOH/g) was heated to 80°C and stirred. 2.88 g of isophorone diisocyanate was slowly added dropwise. The mixture was heated and stirred for 2 hours, and then heated and stirred at 120°C for 20 hours.

After cooling, 200 g of a solvent consisting of an equal weight mixture of toluene and MEK was added and dissolved to obtain a solution with a solids concentration of approximately 20 wt % (hereinafter referred to as solution C).

(Example 4) (Adhesive Preparation) 50 g of the same hydroxyl-terminated polyisobutylene as in Example 3 was dissolved in dehydrated THF, 2.57 g of adipic acid dichloride was added, and the pressure was reduced to approximately 1 mmHg while stirring. The mixture was heated and stirred at 65-70°C for 4 hours, and the THF was evaporated to obtain a reaction mixture. 0.01 g of titanium tetra-n-butoxide was added to the reaction mixture, and the reaction was continued at 180°C for 3 hours while the pressure was reduced to below 1 mmHg. After cooling, 200 g of a solvent consisting of an equal weight mixture of toluene and MEK was added and dissolved to obtain a solution with a solids concentration of approximately 20% by weight (hereinafter referred to as Solution D).

Example 5 (Adhesive Production) 28.9 g of a 75 wt% solution of trimethylolpropane-modified isophorone diisocyanate in ethyl acetate was heated to 80°C, and 50 g of a 40 wt% MEK solution of the same hydroxyl-terminated 1,2-polybutadiene hydrogenated compound as in Example 1 was added dropwise. The mixture was heated to 120°C with stirring under a nitrogen atmosphere and allowed to react for 2 hours. After evaporating the solvent and cooling, 48.9 g of a solvent consisting of an equal weight mixture of toluene and MEK was added and dissolved to obtain a solution with a solids concentration of approximately 20 wt% (hereinafter referred to as Solution E).

Example 6 (Preparation of Polyester Polyol) 5.07 g of terephthaloyl dichloride, 5.07 g of isophthaloyl dichloride, and 5.311 g of neopentyl glycol were dissolved in 50 g of dehydrated THF and heated at 60°C for 1 hour under a reduced pressure of several mmHg. 0.01 g of titanium tetra-n-butoxide was added to the resulting oily product. The pressure was then reduced to less than 1 mmHg, and the mixture was stirred at 180°C for 1 hour to obtain a glassy (amorphous at room temperature) polymer. Thermal analysis using a differential scanning calorimeter (DSC) revealed that the glass transition temperature of this product was 67°C. Furthermore, the molecular weight of this product, calculated from its hydroxyl value, was 18,000. This product will be referred to as Polyester Polyol F.

Example 7 (Preparation of Polyester Polyol) Polymerization was carried out in the same manner as in Example 6 using 4.06 g of terephthaloyl dichloride, 4.06 g of isophthaloyl dichloride, 1.83 g of adipic acid dichloride, and 5.311 g of neopentyl glycol to obtain a polymer. Thermal analysis using DSC revealed that the glass transition temperature of this product was 6°C. Furthermore, the molecular weight calculated from the hydroxyl value of this product was 22,000. Hereafter, this product will be referred to as polyester polyol G.

(Example 8) (Adhesive Solution Composition) Adhesive solutions L to Q were prepared using the polyester polyols F and G described above and the following raw materials, with the compositions shown in Table 1.

Silane coupling agent H: 3-glycidoxypropyltrimethoxysilane.

Polyisocyanate I: Trimethylolpropane-modified tolylene diisocyanate.

Polyisocyanate J: Trimethylolpropane modified isophorone diisocyanate.

Polyisocyanate K: Isocyanurate of hexamethylene diisocyanate.

Solvent: toluene/ethyl acetate mixed solvent (volume ratio 1/1).

(Example 9) (Production of Comparative Adhesive) To a 50 wt % solution of 1,6-hexanediol in MEK, isophorone diisocyanate was added dropwise while stirring and refluxing at 80°C such that the NCO group/OH group ratio became 0.95. The mixture was further stirred and refluxed at 80°C for 2 hours, and then diluted with toluene to obtain a solution with a solids concentration of approximately 20 wt % (hereinafter referred to as Solution R).

(Example 10) (Adhesive Evaluation) A butyl-based rubber-containing resin composition with the composition shown in Table 2 was extruded at high temperature to form a rectangular pillar with a base dimension of 12 mm x 12 mm and a height of 5-6 cm. A 6 mm thick glass plate was washed, degreased with MEK, and dried.

Additionally, adhesive solution A' was prepared by adding 1 part by weight of silane coupling agent H and 10 parts by weight of a 66% by weight solution of polyisocyanate J in butyl acetate to 100 parts by weight of solution A obtained in Example 1 and stirring the mixture. This adhesive solution A' was applied to each of two glass plates and air-dried. This process was repeated twice to form adhesive layers with a thickness of approximately 10 μm after drying.

An adhesive-coated glass plate was placed on each of the top and bottom surfaces of the butyl-based rubber-containing resin composition prism, and the plates were pressed together at 100°C and a pressure of 0.5 kgf/ ^cm² for 0.5 hours to bond them together, and then allowed to cool to produce an H-shaped specimen.

The test specimen was left at room temperature for one week to cure, and then subjected to an H-type test specimen adhesion test (JIS A5758). The maximum strength was 6.5 kgf/cm.² The fracture elongation was 400%, and at this fracture point, the rectangular column of the butyl-rubber-containing resin composition fractured into a material. Furthermore, when the same H-shaped specimen was immersed in 60°C hot water for two weeks and then tested for adhesion, no change in adhesion was observed.

In the butyl-rubber-containing resin composition shown in Table 2, the partially vulcanized butyl rubber used had a Mooney viscosity of ML(1+3) 121°C and 45, the low-molecular-weight polyisobutylene had a viscosity-average molecular weight (Staudinger molecular weight) of 12,000, the high-density polyethylene had a melt index of 20, and the tackifier was hydrogenated cyclopentadiene oligomer (softening point 105°C).

(Example 11) (Evaluation of adhesive) Adhesive solution B' was prepared in the same manner as in Example 10, except that solution B was used instead of solution A. H-shaped test specimens were prepared using this adhesive solution B' and their adhesive properties were evaluated in the same manner. The test specimens showed a maximum strength of 6.5 kgf/ ^cm2 and a breaking elongation of 400%, with the prismatic body of the butyl-based rubber-containing resin composition undergoing material failure at break. Furthermore, no change in adhesive properties was observed even after the same H-shaped test specimens were immersed in 60°C warm water for two weeks.

(Example 12) (Evaluation of adhesive) Adhesive solution C' was prepared in the same manner as in Example 10, except that solution C was used instead of solution A. H-shaped test specimens were prepared using this adhesive solution C' and their adhesive properties were evaluated in the same manner. The test specimens showed a maximum strength of 6.5 kgf/ ^cm2 and a breaking elongation of 400%, with the prismatic body of the butyl-based rubber-containing resin composition undergoing material failure at break. Furthermore, no change in adhesive properties was observed even after the same H-shaped test specimens were immersed in 60°C warm water for two weeks.

(Example 13) (Evaluation of adhesive) Adhesive solution D' was prepared in the same manner as in Example 10, except that solution D was used instead of solution A. H-shaped test specimens were prepared using this adhesive solution D' and their adhesive properties were evaluated in the same manner. The test specimens showed a maximum strength of 6.5 kgf/ ^cm2 and a breaking elongation of 400%, with the prismatic body of the butyl-based rubber-containing resin composition undergoing material failure at break. Furthermore, no change in adhesive properties was observed even after the same H-shaped test specimens were immersed in 60°C warm water for two weeks.

(Example 14) (Evaluation of adhesive) Adhesive solution E' was prepared in the same manner as in Example 10, except that solution E was used instead of solution A. H-shaped test specimens were prepared using this adhesive solution E' and their adhesive properties were evaluated in the same manner. The test specimens showed a maximum strength of 6.5 kgf/ ^cm2 and a breaking elongation of 400%, with the prismatic body of the butyl-based rubber-containing resin composition undergoing material failure at break. Furthermore, no change in adhesive properties was observed even after the same H-shaped test specimens were immersed in 60°C hot water for two weeks.

(Example 15) (Evaluation of adhesive) An H-shaped specimen was prepared in the same manner as in Example 10, except that adhesive L was used instead of adhesive solution A', and the adhesive properties were evaluated in the same manner. The maximum strength was 6.5 kgf/ ^cm2 and the breaking elongation was 400%, and the prismatic body of the butyl-based rubber-containing resin composition broke at the break. Furthermore, no change in the adhesive properties was observed even after immersing the same H-shaped specimen in 60°C hot water for 2 weeks.

(Example 16) (Evaluation of adhesive) An H-shaped specimen was prepared in the same manner as in Example 10, except that adhesive solution A' was replaced with adhesive M, and the adhesive properties were evaluated in the same manner. The maximum strength was 6.5 kgf/ ^cm2 and the breaking elongation was 400%, with the prismatic body of the butyl-based rubber-containing resin composition undergoing material failure at break. Furthermore, no change in the adhesive properties was observed even after the same H-shaped specimen was immersed in 60°C hot water for two weeks.

(Example 17) (Evaluation of adhesive) An H-shaped specimen was prepared in the same manner as in Example 10, except that adhesive solution A' was replaced with adhesive N, and the adhesive properties were evaluated in the same manner. The maximum strength was 6.5 kgf/ ^cm2 and the elongation at break was 400%, with the prismatic body of the butyl-based rubber-containing resin composition undergoing material failure at break. Furthermore, no change in the adhesive properties was observed even after the same H-shaped specimen was immersed in 60°C hot water for two weeks.

(Example 18) (Evaluation of adhesive) An H-shaped specimen was prepared in the same manner as in Example 10, except that adhesive P was used instead of adhesive solution A', and the adhesive properties were evaluated in the same manner. The maximum strength was 6.5 kgf/ ^cm2 and the elongation at break was 400%, and the prismatic body of the butyl-based rubber-containing resin composition broke at the break. Furthermore, no change in the adhesive properties was observed even after immersing the same H-shaped specimen in 60°C hot water for 2 weeks.

(Example 19) (Evaluation of adhesive) An H-shaped specimen was prepared in the same manner as in Example 10, except that adhesive Q was used instead of adhesive solution A', and the adhesive properties were evaluated in the same manner. The maximum strength was 6.5 kgf/ ^cm2 and the elongation at break was 400%, and the prismatic body of the butyl-based rubber-containing resin composition broke at the break. Furthermore, no change in the adhesive properties was observed even after immersing the same H-shaped specimen in 60°C hot water for 2 weeks.

(Example 20) (Evaluation of adhesive) Adhesive solution AE was prepared in the same manner as in Example 10, except that 100 parts by weight of a mixed solution consisting of 50 parts by weight of Solution A and 50 parts by weight of Solution E was used instead of Solution A, and 10 parts by weight of a 66% by weight solution of butyl acetate of Polyisocyanate J was not added. H-shaped test specimens were prepared using this adhesive solution AE, and their adhesive properties were evaluated in the same manner. The test specimens showed a maximum strength of 6.5 kgf/ ^cm2 and a breaking elongation of 400%, with the prismatic body of the butyl-based rubber-containing resin composition undergoing material failure at break. Furthermore, no change in adhesive properties was observed even after the same H-shaped test specimens were immersed in 60°C warm water for two weeks.

(Example 21) (Evaluation of adhesive) Adhesive solution AE' was prepared in the same manner as in Example 20, except that 100 parts by weight of a mixed solution consisting of 30 parts by weight of Solution A and 70 parts by weight of Solution E was used instead of 100 parts by weight of a mixed solution consisting of 50 parts by weight of Solution A and 50 parts by weight of Solution E. H-shaped test specimens were prepared using this adhesive solution AE' and their adhesive properties were evaluated in the same manner. The test specimens showed a maximum strength of 6.5 kgf/ ^cm2 and a breaking elongation of 400%, with the prismatic body of the butyl-based rubber-containing resin composition undergoing material failure at break. Furthermore, no change in adhesiveness was observed even after immersing the same H-shaped test specimens in 60°C warm water for two weeks.

(Example 22) (Evaluation of Comparative Adhesive) Adhesive solution R' was prepared in the same manner as in Example 10, except that solution R was used instead of solution A. H-shaped test specimens were prepared using this adhesive solution R' and the adhesive properties were evaluated in the same manner. The test specimens showed a maximum strength of 4.0 kgf/ ^cm2 and a breaking elongation of 32%, with the fracture occurring at the interface between the prismatic body of the butyl-based rubber-containing resin composition and the adhesive. Furthermore, no change in adhesive properties was observed even after the same H-shaped test specimens were immersed in 60°C warm water for two weeks.

(Examples 23-36) (Durability Evaluation of Double-Glazing Glass) Using the adhesive solutions A'-E', L-Q, R, AE, and AE' described above, double-glazing glass panels with the structure shown in Figure 2 were manufactured and adhesive performance tests were conducted. The adhesive solution was applied to the peripheral surfaces of two clean glass panes 1a and 1b, and after air drying, the glass panes were placed with the adhesive solution-coated surfaces facing each other. A butyl-based rubber-containing resin composition with the composition listed in Table 2 was extruded at high temperature onto the adhesive solution-coated surface between the glass panes to form a spacer 20. The molded spacer was then bonded to the glass panes with the adhesive.

The resulting double-glazing glass 10 was subjected to a durability test in accordance with JIS R3209. The results are shown in Tables 3 and 4. For comparison, the same test was also conducted on double-glazing glass obtained in the same manner except that no adhesive was used. Six double-glazing glass specimens were used in this durability evaluation, and the values in Tables 3 and 4 indicate the highest dew point (°C) in the air layer of each specimen.

The molded product of the butyl rubber-containing resin composition had a JIS A hardness (HsA) of 60 at 25° C., and a water vapor permeability coefficient according to JIS K7149 of 1×10 ⁻⁹ (cm ³ ·cm/(cm ² ·sec·cmHg)).

As shown in Examples 23 to 34, when the adhesive of the present invention was used, no increase in dew point was observed even at the end of the JIS durability evaluation Class III, and all were judged to have passed, whereas when an adhesive other than the adhesive of the present invention was used (Example 35) or when no adhesive was used (Example 36), peeling occurred at the interface between the spacer and the glass by the end of the JIS durability evaluation Class III, and the dew point of the air in the air layer rose. In other words, both cases did not pass the durability test.

The adhesive of the present invention has good adhesion durability between a butyl-based rubber-containing resin composition and a glass plate. In the production of double-glazing using a spacer made of a butyl-based rubber-containing resin composition and a glass plate, the adhesive is suitable for bonding a spacer made of a butyl-based rubber-containing resin composition to a glass plate.

───────────────────────────────────────────────────── (Note) This publication is based on the publication published internationally by the International Bureau of Patents (WIPO). The effect of the international publication of the Japanese patent application (Japanese utility model registration application) related to this publication arises pursuant to Article 184-10, Paragraph 1 of the Patent Act (Article 48-13, Paragraph 2 of the Utility Model Act) and is unrelated to this publication.

Claims (9)

[Claims] 1. An adhesive for bonding a resin composition containing butyl rubber to inorganic glass, the adhesive comprising at least one active ingredient selected from the group consisting of (A) a mixture of a terminally reactive oligomer having a repeating unit of a divalent hydrocarbon group having four carbon atoms and a chain extender, (B) a reaction product of a terminally reactive oligomer having a repeating unit of a divalent hydrocarbon group having four carbon atoms and a chain extender, (C) a mixture of a polyester polyol and a polyisocyanate, and (D) a reaction product of a polyester polyol and a polyisocyanate. 2. The adhesive of claim 1, wherein the chain extender is a polyisocyanate, a polycarboxylic acid, or a reactive acid derivative of a polycarboxylic acid. 3. The adhesive according to claim 1, wherein the reactive terminal oligomer having a repeating unit of a divalent hydrocarbon group having four carbon atoms is a hydroxyl group-terminated oligomer or a carboxyl group-terminated oligomer. 4. The adhesive according to claim 1, wherein the reaction product of a terminally reactive oligomer having a repeating unit of a divalent hydrocarbon group having four carbon atoms and a chain extender is a polyurethane polymer or an isocyanate-terminated prepolymer that is a reaction product of a hydroxyl-terminated oligomer and a polyisocyanate. 5. The adhesive according to claim 1, wherein the reaction product of the reactive terminal oligomer having a repeating unit of a divalent hydrocarbon group having four carbon atoms and the chain extender is a polyester polymer which is the reaction product of a hydroxyl-terminated oligomer and a polycarboxylic acid or a reactive acid derivative of a polycarboxylic acid. 6. The adhesive of claim 1, wherein the polyester polyol is a polyester polyol that is solid at room temperature. 7. The adhesive according to claim 1, wherein the polyester polyol is a polyester polyol having a residue obtained by removing the hydroxyl group from the carboxyl group of an aromatic dicarboxylic acid. 8. The adhesive of any one of claims 1 to 7, wherein the adhesive further comprises a silane coupling agent. 9. The adhesive according to claim 1, wherein the resin composition containing butyl rubber is a resin composition containing butyl rubber and crystalline polyolefin, with the proportion of crystalline polyolefin relative to the total amount of butyl rubber and crystalline polyolefin being 2 to 50% by weight.