JP2001348550A - Two-part adhesive composition and bonding method - Google Patents

Abstract

(57) [Problem] When a first liquid and a second liquid are brought into contact with each other, they react and harden in a short time at room temperature, have high initial adhesive strength, and are bonded. To obtain a two-part adhesive composition having good workability. A first aqueous solution comprising (A) a vinyl alcohol polymer having a functional group containing active hydrogen in the molecule and (B) an isobutylene-maleic anhydride imide resin having an imide group in the molecule. A two-part adhesive composition comprising a liquid and a second liquid containing a water-soluble aldehyde compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-part adhesive composition and a bonding method using the same. More specifically, the present invention relates to a two-part adhesive composition having a particularly high initial curing rate and excellent workability during bonding.

[0002]

2. Description of the Related Art Recently, in the wood products industry, it has been studied to make a production process continuous by a conveyor system. Therefore, an adhesive having a high bonding speed has been demanded. For this purpose, cyanoacrylate-based instant adhesives have been proposed, but are extremely expensive and not practical. Further, a two-liquid separation coating type adhesive composition using a urea resin-based adhesive as a first liquid, and mixing a strong acid such as phosphoric acid with an aqueous solution of a polymer compound such as polyvinyl alcohol (PVA) as a second liquid. Has been proposed. However, since this adhesive composition uses a strong acid, there is a disadvantage that the resin component contained in the adhesive is easily aged, and furthermore, the adherend is easily stained or deteriorated.

An aqueous solution of a polymer compound having an imide group in the molecule (isobutylene-maleic anhydride imide resin) or a synthetic resin emulsion containing the polymer compound is used as a first liquid, and an aqueous solution of an aldehyde compound is used as a second liquid. 2. Description of the Related Art A two-liquid separation coating type adhesive composition which is a liquid is known (JP-A-56-90867). However, this adhesive composition has a disadvantage that the final adhesive strength is low. Further, an aqueous solution and / or an aqueous emulsion of a polymer compound having an acetoacetyl group in a molecule is used as a first solution,
A solution containing an aldehyde compound or a hydrazine compound is
There are known two-component, separate-coating-type adhesive compositions as liquids (JP-A-60-202176 and JP-A-61-176176).
No. 78883). However, in this adhesive composition,
The storage stability of the first liquid is poor, and there is a problem in reproducibility of the adhesive performance. Furthermore, a two-part separation coating type adhesive composition in which an aqueous solution and / or aqueous emulsion of a vinyl alcohol polymer having an amino group in the molecule is used as a first liquid and a liquid containing an aldehyde compound is used as a second liquid is proposed. However, there is a case where there is a problem in the initial adhesive strength (Japanese Patent Application Laid-Open No. 10-112016).

In Japanese Patent Application Laid-Open No. 3-281683, an aqueous solution of a polymer compound (polyamine) having a primary or secondary amino group in the molecule or a mixture of the polymer compound and a synthetic resin emulsion is used. There has been proposed a two-liquid separation coating adhesive composition in which an aldehyde compound is used as a first liquid and a second liquid is used. However, this adhesive composition has a problem that the storage stability of the first liquid is poor and the efficiency of crosslinking with the aldehyde compound is low, so that sufficient fast curability cannot be obtained.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks of the prior art and to develop a high initial adhesive strength by curing at room temperature in a short time, thereby making the bonding operation extremely difficult. An object of the present invention is to provide a two-part adhesive composition that can be performed smoothly with low energy cost and with good productivity. Further, the object of the present invention is to have excellent storage stability and mechanical stability together with the above-mentioned property of fast curing,
The components are unlikely to settle, separate, or agglomerate even if left unattended.Also, the components are unlikely to settle, separate, or agglomerate when subjected to the action of rocking, stirring, etc. during transportation or handling. Another object of the present invention is to provide a two-part adhesive composition which can maintain its adhesive performance in a good condition. Furthermore, an object of the present invention is to provide a compound having such excellent properties.
An object of the present invention is to provide a bonding method using a liquid type adhesive composition.

[0006]

Means for Solving the Problems As a result of intensive studies by the present inventors to achieve the above object, (A) a vinyl alcohol polymer having a functional group containing active hydrogen in the molecule and (B) a molecule An aqueous liquid containing an isobutylene-maleic anhydride imide resin having an imide group therein is used as a first liquid, and a liquid containing a water-soluble aldehyde compound is used as a second liquid to prepare a two-part adhesive composition. When bonding is performed using a two-component adhesive composition, in particular, the first liquid is applied to one adherend surface, the second liquid is applied to another adherend surface, and the adherend surfaces are bonded to each other. When a close contact is made, a high initial adhesive strength (adhesive strength within approximately 5 minutes after the adhered surfaces are brought into close contact with each other) is exhibited in a short time at room temperature, thereby improving the productivity of the adhesive work with good workability. What can be done with good and low energy consumption,
And it has been found that the adherend obtained thereby exhibits high final adhesive strength (adhesive strength approximately 24 hours or more after the adhered surfaces are brought into close contact with each other). Furthermore, the present inventors have found that such a two-part adhesive composition, when the first part and the second part are individually stored in a non-mixed state, the separation, sedimentation, aggregation, etc. of the components. It has been found that it is stable without generation, and that its adhesion performance is maintained without deterioration even after long-term storage. Further, they have found that the water-resistant adhesive strength is improved by further blending a polyvalent epoxy compound with the above-mentioned first liquid and / or second liquid.
The present invention has been completed based on these findings.

That is, the present invention relates to an aqueous solution containing (A) a vinyl alcohol polymer having a functional group containing active hydrogen in the molecule and (B) an isobutylene-maleic anhydride resin having an imide group in the molecule. A first liquid comprising a liquid;
The present invention relates to a two-part adhesive composition comprising a second liquid containing a water-soluble aldehyde compound. The present invention also relates to a two-part adhesive composition in which the first liquid further contains a polyvalent epoxy compound. Further, the present invention relates to a two-part adhesive composition in which the second liquid further contains a polyvalent epoxy compound.

[0008] The present invention provides a method for applying the first liquid of any of the above two-part adhesive compositions to a first adherend, and applying the second liquid to a second adherend. And an adhesion method wherein both application surfaces are brought into close contact with each other for adhesion.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. First, the two-part adhesive composition of the present invention has (A) a vinyl alcohol polymer having a functional group containing active hydrogen in the molecule and (B) an imide group in the molecule as a first liquid. An aqueous liquid containing an isobutylene-maleic anhydride resin is used. Among them, (A) a vinyl alcohol polymer having a functional group containing active hydrogen in the molecule is not particularly limited as long as it is a vinyl alcohol polymer having a functional group containing active hydrogen in the molecule. Among them, a vinyl alcohol polymer having at least one functional group selected from a primary amino group, a secondary amino group, and an acetoacetyl group in a molecule is particularly preferable from the viewpoint of improving adhesion to a substrate. A vinyl alcohol polymer having one or more functional groups selected from a primary amino group, a secondary amino group, and an acetoacetyl group in the molecule is synthesized by a conventionally known method.

For example, in the case of a vinyl alcohol polymer having a primary or secondary amino group, (1) an ethylenically unsaturated monomer having a primary amino group or a secondary amino group,
A method of copolymerizing an ethylenically unsaturated monomer having a functional group capable of forming a primary amino group or a secondary amino group by hydrolysis and a vinyl ester such as vinyl acetate, and then saponifying the copolymer. (2) Addition reaction of a mercaptan having an amino group with a NaOH catalyst as a catalyst to a side chain epoxy group of a polymer comprising a monomer having an epoxy group such as allyl glucidyl ether and a vinyl ester such as vinyl acetate. After the saponification, or (3) converting a compound having a functional group capable of reacting with a hydroxyl group of a conventionally known polyvinyl alcohol into a molecule and having a primary or secondary amino group into a vinyl alcohol-based polymer. It can be obtained by a reaction method or the like. There is also a method of (4) polymerizing an ethylenically unsaturated monomer having a primary amino group or a secondary amino group in the presence of a vinyl alcohol-based polymer having a mercapto group. A polymer is obtained. In the case of a vinyl alcohol polymer having an acetoacetyl group in the molecule,
Usually, it is obtained by a post-reaction by adding diketene to a conventionally known vinyl alcohol-based polymer. In addition, as a vinyl alcohol-based polymer containing a functional group having active hydrogen, diacetone acrylamide-modified polyvinyl alcohol is also known, and can achieve the object of the present invention. Primary amino group,
Generally lower than vinyl alcohol polymers having one or more functional groups selected from secondary amino groups and acetoacetyl groups.

[0011] The content of the functional group having active hydrogen is not particularly limited.
It can be appropriately selected according to various situations such as the type and amount of components contained in the first liquid and the second liquid. Usually, based on all the structural units constituting the vinyl alcohol polymer having a functional group having an active hydrogen in the molecule, the ratio of the functional group having an active hydrogen (primary amino group, secondary amino group, acetoacetyl) In the case of having a group or the like, the ratio of the total structural units) is preferably from 0.1 to 30 mol%, more preferably from 0.5 to 25 mol%.
Is the ratio of the structural unit having an active hydrogen-containing functional group in a vinyl alcohol polymer having a functional group having active hydrogen (hereinafter sometimes abbreviated as active hydrogen group-containing PVA) less than 0.1 mol%? Or when it exceeds 30 mol%, the initial adhesive strength and the final adhesive strength may not be sufficiently high.

The degree of polymerization of the active hydrogen group-containing PVA is as follows:
The purpose of use of the adhesive composition, the type and amount of other components contained in the adhesive composition, may vary depending on the phase morphology of the adhesive composition, etc., usually, its polymerization degree is 100 or more It is preferable from the viewpoint of initial adhesive strength and final adhesive strength.
More preferably, it is 0-8000. The degree of saponification of the active hydrogen group-containing PVA also varies depending on the various requirements as described above. In general, it is necessary that 50 mol% or more of the structural unit based on vinyl alcohol is saponified. It is preferable from the point of properties, and it is more preferable that 80 to 99.9 mol% is saponified. The active hydrogen group-containing PVA may contain other structural units together with the structural unit based on vinyl alcohol and the structural unit having an active hydrogen group, as long as the effect of the present invention is not hindered.

As (B) an isobutylene-maleic anhydride imide resin having an imide group in the molecule, a known resin is used, and the trade name is Isoban 30 manufactured by Kuraray Co., Ltd.
4. Isoban 306 or the like can be used.

In the two-part adhesive composition of the present invention, the first part comprises (A) an active hydrogen group-containing PVA and (B) an isobutylene-maleic anhydride resin having an imide group in the molecule. It is an aqueous liquid containing at least water and using water as a medium. It is desirable that the aqueous liquid be capable of maintaining a stable aqueous liquid state without causing separation, sedimentation, aggregation, etc. of components before use in the bonding operation. The active hydrogen group-containing PVA may be used in an aqueous solution, or a polyvinyl acetate emulsion using the active hydrogen group-containing PVA as a protective colloid may be used.

The use ratio of (A) and (B) of the first liquid used in the two-part adhesive composition of the present invention is not particularly limited.
Usually (A) / (B) is 5/95 to 95/5 in solid content, preferably 10/90 to
90/10, more preferably 20/80 to 80/20. If the compounding ratio is out of the above range, there is a possibility that problems such as poor initial adhesive strength and reduced final adhesive strength may occur.

The first liquid used in the two-part adhesive composition of the present invention is stable even when left for a long period of time, and does not cause sedimentation, aggregation, or coagulation of the components contained in the emulsion. Even if some mechanical action (for example, stirring or rocking) is applied from the outside, the stable dispersion state is not destroyed, and good adhesive performance can be maintained for a long period of time. Although the concentration of the first liquid is not particularly limited, it is usually 5 to 60.
%, Preferably 10-55%, more preferably 20-5%
Used at a concentration of 5%. If the concentration is lower than 5%,
There is a concern that the initial adhesive strength will decrease. The concentration is 60%
If the ratio exceeds 1, the stability of the first liquid may be reduced.

In the two-part adhesive composition of the present invention, an aqueous liquid containing a water-soluble aldehyde compound is used as the second liquid together with the first liquid.

Examples of the water-soluble aldehyde compound include compounds such as formaldehyde, acetaldehyde, propionaldehyde, crotonaldehyde, benzaldehyde, glyoxal, malonaldehyde, fuchsindialdehyde, vimelindialdehyde, suberindialdehyde, glutaraldehyde, dialdehyde starch and the like. Glyoxal, glutaraldehyde, dialdehyde starch and the like are preferably used.

In the two-part adhesive composition of the present invention, the water-resistant adhesive strength can be improved by further blending a polyvalent epoxy compound with the first and / or second liquid. Becomes Active hydrogen group-containing P used for the first liquid
Both VA and isobutylene-maleic anhydride resin react and crosslink with the polyvalent epoxy compound. For this reason, it is considered that since both active hydrogen group-containing PVA and isobutylene-maleic anhydride resin are used, a remarkable water-resistant adhesiveness is exhibited in order to obtain a dense crosslinked structure. The blending amount of the polyhydric epoxy compound with respect to the first liquid is not particularly limited, but usually 0.5 to 30 parts by weight, preferably 1 to 20 parts by weight, per 100 parts by weight of the first liquid. If the amount is less than 0.5 part, improvement in water resistance may not be observed. If the amount exceeds 30 parts by weight, there is a concern that the storage stability of the first liquid may deteriorate. Also, the amount of the polyhydric epoxy compound in the second liquid is not particularly limited, but is usually 1 to 100 parts by weight of the second liquid.
５０50 parts by weight, preferably 2-30 parts by weight are used. If the amount is less than 1 part, the water resistance may not be improved. If the amount exceeds 50 parts by weight, the initial adhesive strength may decrease. Examples of polyhydric epoxy compounds include bisphenol A diglycidyl ether, bisphenol A diβ-methyl glycidyl ether, bisphenol F diglycidyl ether, tetrahydroxyphenylmethane tetraglycidyl ether, resorcinol diglycidyl ether, brominated bisphenol A diglycidyl ether, and chlorinated Bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, diglycidyl ether of bisphenol A alkylene oxide adduct, novolak glycidyl ether, polyalkylene glycol diglycidyl ether,
Glycidyl ether type such as glycerin triglycidyl ether, pentaerythritol diglycidyl ether, epoxy urethane resin; glycidyl ether / ester type such as P-oxybenzoic acid glycidyl ether / ester; diglycidyl phthalate, diglycidyl tetrahydrophthalate Glycidyl ester type such as diglycidyl ester of hexahydrophthalic acid, diglycidyl acrylate, diglycidyl ester of dimer; glycidylamine type such as glycidylaniline, tetraglycidyldiaminodiphenylmethane, triglycidyl isocyanurate, triglycidylaminophenol; epoxy Linear aliphatic epoxy resins such as hydrogenated polybutadiene and epoxidized soybean oil; 3,4 epoxy-6 methylcyclohexylmethyl Tyl-3,4 epoxy-6 methylcyclohexanecarboxylate, 3,4 epoxycyclohexylmethyl (3,4-epoxycyclohexane) carboxylate, bis (3,4-epoxy-6methylcyclohexylmethyl) adipate, vinylcyclohexene diepoxide, Dicyclopentadiene oxide,
Examples include alicyclic epoxy resins such as bis (2,3-epoxycyclopentyl) ether and limonenedioxide, and polyamide epichlorohydrin.

In the two-part adhesive composition of the present invention, the first part may contain a filler, if necessary, for the purpose of increasing the amount and strengthening. Is
Examples thereof include calcium carbonate, kaolin, baryta, wood flour, plant flour and the like, and one or more of these can be contained. Further, the first liquid may contain a plasticizer, a colorant, and other compounding agents as necessary. In addition, the second liquid in the two-part adhesive composition of the present invention is also one or more of a colorant, a surfactant, a viscosity modifier, and the like, if necessary, as long as the performance of the second liquid is not impaired. Species or more may be appropriately contained. In addition, you may mix and use a polyvalent isocyanate compound with 1st liquid and / or 2nd liquid.

In the two-part adhesive composition of the present invention,
The ratio of the first liquid and the second liquid depends on the use and use situation of the adhesive composition, the type of components contained in both liquids, the method of applying the adhesive liquid to the adherend, the type of adherend, and the like. Usually, the second liquid is preferably 0.2 to 150 parts by weight, more preferably the second liquid is 1 to 100 parts by weight based on 100 parts by weight of the first liquid.
It is preferable to use 100 parts by weight.

Before the two-part adhesive composition of the present invention is used in the bonding operation, the first liquid and the second liquid are separated from each other (non-mixed state) and put in a container or the like. , Stored, distributed and sold. Then, in performing the bonding operation using the two-part adhesive composition of the present invention, the first liquid of the two-part adhesive composition is applied to the first adherend surface,
A method in which a liquid is applied to the second adherend surface, the two applied surfaces are brought into close contact with each other, and the adhesive composition is reacted and cured to bond the adhesive composition (that is, a two-liquid separation application method), or the first method immediately before the bonding is performed. A method of mixing the liquid and the second liquid and quickly applying the mixed liquid to the adherend to perform adhesion can be adopted. In the two-part adhesive composition of the present invention, the first liquid and the second liquid are used. When the second liquid is brought into contact, the reaction curing usually proceeds rapidly even at room temperature, so the former two-liquid separation coating method is preferably used. When the two-component adhesive composition of the present invention is bonded by a two-component separation coating method, its properties, such as its quick-curing property and high initial adhesive strength, are sufficiently exhibited, resulting in extremely good work. The bonding operation can be performed in a short time with high productivity at low cost and low energy cost. For this reason, the two-part adhesive composition of the present invention is particularly suitable as a two-part separate application adhesive composition.

In the case of performing the bonding operation by the above-described two-liquid separation coating method, the adhered surface coated with the first liquid and the coated surface coated with the second liquid are brought into close contact with each other, and then pressed and pressed. Since high initial adhesive strength is developed in a very short time (usually within 1 to 5 minutes), pressing and pressing can be released in a short time, shortening the working time, simplifying the working process,
It is possible to achieve simplification of the device, reduction of energy cost, and the like. Then, the adherend, which was able to obtain a sufficiently high adhesive strength by pressing and pressing, releases the pressed and pressed state, and is left and cured to obtain an adherend having a sufficiently high final adhesive strength. Can be obtained.
In the case of a conventional adhesive using water as a medium, a sufficient final adhesive strength cannot be generally obtained unless pressed and pressed for a long time at room temperature, but the two-part adhesive composition of the present invention is not used. When a product is used, due to its fast-curing property, even if the pressing and pressing are performed for a short period of time, it is possible to perform bonding with sufficient final bonding strength after curing and curing, which is extremely useful in this respect.

In performing the bonding operation using the two-part adhesive composition of the present invention, the first part is applied after the second part has been applied to one of the adherends and dried. The two-part adhesive composition of the present invention can be applied continuously to woodworking work, since it can be applied to another adherend surface and both adherent surfaces can be adhered and adhered to each other to perform desired bonding. A simple conveyor system is possible.

Using the two-part adhesive composition of the present invention,
The amount of the first liquid and the second liquid applied to the surface to be adhered in the case of performing the adhesion by the liquid separation application method is not particularly limited, and depends on the type and state of the adherend, the component content of the adhesive composition, and the like. In general, the amount of the first liquid to be applied to the first surface is set to about 10 to 500 g / m2, and the amount of the second liquid to be applied to the second surface is 5 to 100 g. It is preferable that the adhesion is performed by bringing both application surfaces into close contact with each other at about / m2, since high adhesion strength can be obtained while effectively using the first liquid and the second liquid without waste.

When bonding is performed using the two-part adhesive composition of the present invention, the active hydrogen group-containing PVA and isobutylene-maleic anhydride contained in the first part due to the water-soluble aldehyde compound contained in the second part. The gelling reaction of the acid imide resin occurs, and the initial adhesive strength is improved. Active hydrogen group-containing PV
A higher initial adhesive strength is obtained by the presence of both A and the isobutylene-maleic anhydride resin.

The two-part adhesive composition of the present invention comprises plywood,
Glued lumber, MDF, slate board, silicon board and other wood materials, flash panel manufacturing, rim bonding, roll-in bonding, various wood materials, melamine resin decorative materials, bakelite, and other plastic materials; corrugated paperboard, It can be effectively used for bonding paper materials such as kraft paper; fabrics and other fiber products; and inorganic plates. In bonding the above-mentioned various materials using the two-component adhesive composition of the present invention, it can be used for both bonding between materials of the same type and bonding between different materials, and in particular, bonding between woods. Suitable for. However, of course, it is not limited thereto. Therefore, by using the two-part adhesive composition of the present invention, it is not limited at all, for example, flash panel, flat glue or glued glue, tenon, dowel, tome, hagi, The bonding and other assembling and bonding operations for manufacturing and assembling square blocks and boxes, as well as for manufacturing shoes, are quick and labor-saving, and can be performed well at room temperature.

[0028]

EXAMPLES The present invention will now be described specifically with reference to examples and comparative examples, but the present invention is not limited to these examples. In the following examples, “%” and “parts” mean “% by weight” and “parts by weight”, respectively, unless otherwise specified.

Example 1 17% of a primary amino group-modified PVA (polymerization degree 1000, saponification degree 98%, primary amino group content 2 mol%) obtained by a known method (Japanese Patent Application Laid-Open No. 10-36440). The aqueous solution was prepared. Further, an isobutylene-maleic anhydride resin having an imide group (Isoban 30 manufactured by Kuraray Co., Ltd.)
4) 80 parts of 40 parts, 7 parts of 25% ammonia water and 80 parts of water
The mixture was stirred and dissolved under heating at ℃ to prepare a 31.5% aqueous solution. 200 parts of a 17% aqueous solution of the primary amino group-modified PVA, 100 parts of an aqueous solution of isobutylene-maleic anhydride resin,
Calcium carbonate (Toyo Fine Chemical; trade name P-
30) 100 parts were blended to prepare a first liquid. On the other hand, a 15% glyoxal aqueous solution was prepared as a second liquid. Next, a pair of adherends consisting of two test pieces (beech wood, mosaic mesh) of length × width × thickness = 25 × 25 × 10 mm was used for each adhesive composition, 5 pairs per test point. Prepared. The first liquid prepared above is applied to the adhesive surface of one test piece of the pair of adherends (applied amount of about 250 g / m2), and the second liquid prepared above is applied to the adhesive surface of the other test piece. And apply (applying amount of about 70g
/ M2), and the both application surfaces were bonded together and pressed (pressing pressure: about 10 kg / cm2). Then, for each adherend pair,
Pressing was performed for the time shown in Table 1. After each pressing time, the pressure was released, and after each was cured for 2 minutes or 24 hours, the adhesive strength was measured according to JIS K-6852 “Compressive shear adhesive strength of adhesive”. And the average value of five pairs was taken as the adhesive strength (compression shear adhesive strength).

Further, in the above-mentioned test of the adhesive strength after curing for 24 hours, the ratio [breakage rate (%)] of destruction occurring at the part of the adherend without causing peeling of the adhered surface of the adherend. ]
At the same time, and are shown in parentheses in the following table. The higher the value of the breaking ratio, the higher the adhesive strength of the adhesive composition. The above-mentioned bonding operation and test were all performed in an atmosphere at 20 ° C. Table 1 shows the results.

Example 2 A test was performed in the same manner as in Example 1 except that a 15% aqueous solution of glutaraldehyde was used instead of glyoxal used in Example 1. Table 1 with the results
Shown in

Example 3 A test was conducted in the same manner as in Example 1 except that a 15% aqueous solution of dialdehyde starch was used instead of glyoxal used in Example 1. The results are shown in Table 1.

Example 4 Instead of using the primary amino group-modified PVA used in Example 1, acetoacetyl group-containing PVA (Gosefimer Z-200 manufactured by Nippon Synthetic Chemical Industry Co., Ltd .; acetoacetyl group content 5 Mol%, degree of polymerization 1000, degree of saponification 9
The test was conducted in the same manner as in Example 1 except that 8 mol%) was used. The results are shown in Table 1.

Example 5 PVA containing acetoacetyl group (Nippon Synthetic Chemical Industry Co., Ltd.)
Gohsefimer Z-200; acetoacetyl group content 5 mol%, polymerization degree 1000, saponification degree 98 mol%) 5
100 parts of water was added to the mixture and heated to 95 ° C. to prepare an aqueous solution of acetoacetyl group-containing PVA. The whole amount of the adjusted aqueous solution was charged into a pressure-resistant autoclave, and 100 parts of vinyl acetate was
And after purging with nitrogen, ethylene was added to 40 kg / cm
To 2. Then, the internal temperature was raised to 60 ° C. and 10
One part of a 1% aqueous solution of tartaric acid was charged. Thereafter, 5 parts of a 1% aqueous hydrogen peroxide solution was added over 3 hours to carry out copolymerization. The copolymerization was completed in 4 hours, the solid content concentration was 53.0%, and the viscosity was 1
A stable vinyl acetate-ethylene copolymer aqueous emulsion of 120 mPa · s using acetoacetyl group-containing PVA as a protective colloid was obtained. A test was performed in the same manner as in Example 1 except that the aqueous emulsion was used instead of the aqueous solution of the primary amino group-modified PVA used in Example 1.
The results are shown in Table 1.

Comparative Example 1 Instead of using the primary amino group-modified PVA used in Example 1, unmodified PVA (PVA-110 manufactured by Kuraray Co., Ltd .;
The test was performed in the same manner as in Example 1 except that the polymerization degree was 1000 and the saponification degree was 98.5 mol%. The results are shown in Table 1.

Comparative Example 2 An aqueous solution of isobutylene-maleic anhydride resin 3 was used without using the primary amino group-modified PVA used in Example 1.
A test was conducted in the same manner as in Example 1 except that 100 parts of calcium carbonate was mixed with 300 parts of a 1.5% aqueous solution to prepare a first liquid. The results are shown in Table 1.

Comparative Example 3 Primary amino group-modified PVA17 was used without using the aqueous solution of isobutylene-maleic anhydride resin used in Example 1.
A test was conducted in the same manner as in Example 1 except that 100 parts of calcium carbonate was mixed with 300 parts of a 30% aqueous solution to obtain a first liquid.
The results are shown in Table 1.

Comparative Example 4 A test was conducted in the same manner as in Example 1 except that the glyoxal used in Example 1 was not used. The results are shown in Table 1.

Example 6 A polyhydric epoxy compound (ethylene glycol diglycidyl ether) was added to 100 parts of the first liquid prepared in Example 1.
Bonding was performed in the same manner as in Example 1 except that 5 parts were blended to make the first liquid. After the test piece was cured at room temperature for one week, its water-resistant adhesive strength was measured according to JIS K-6852 "Testing method for compressive shear adhesive strength of adhesive". That is,
The test piece was immersed in water at 60 ° C. for 3 hours and measured, and an average value of five pairs was taken to obtain a water-resistant adhesive strength (compression shear adhesive strength). Table 2 shows the results.

Example 7 A polyhydric epoxy compound (ethylene glycol diglycidyl ether) was added to 100 parts of the second liquid prepared in Example 1.
Bonding was carried out in the same manner as in Example 1 except that 5 parts were blended to make the second liquid. The water-resistant adhesive strength was measured according to Example 6. The results are shown in Table 2.

Comparative Example 5 Instead of using the primary amino group-modified PVA used in Example 6, unmodified PVA (PVA-110 manufactured by Kuraray Co., Ltd .; polymerization degree 1000, saponification degree 98.5 mol%) was used. The test was performed in the same manner as in Example 6 except for the above. The results are shown in Table 2.

[0042]

[Table 1]

[0043]

[Table 2]

[0044]

The two-part adhesive composition of the present invention has a
When the liquid and the second liquid are brought into contact, they react and harden in a short time at room temperature and exhibit high initial adhesive strength. Therefore, bonding is performed using the two-part adhesive composition of the present invention. In this case, the bonding operation can be performed with good workability and processability and at low energy cost. Particularly, using the two-part adhesive composition of the present invention, the first liquid is applied to one of the adherends, the second liquid is applied to the other adherent, and both adherent surfaces are adhered to each other. When the bonding is performed by the two-liquid separation coating method, the bonding operation can be performed extremely smoothly due to its fast curing property. When the polyhydric epoxy compound is further added to the first liquid and / or the second liquid, high water-resistant adhesive strength is exhibited, and troubles such as peeling of the bonded portion do not occur. Therefore, the two-part adhesive composition of the present invention makes use of the various excellent properties described above to make use of various woody materials, for example, materials such as wood, chipboard, and hardboard, slate board, and silicon board. Wood materials such as: Melamine resin decorative materials, bakelite, and other plastic materials; Paper materials such as corrugated paperboard and kraft paper; Fabrics and other textiles; Can be used effectively for bonding inorganic boards, especially wood Suitable for bonding.

Continued on front page F term (reference) 4J040 DA141 DD021 DG001 EC021 EC031 EC041 EC061 EC071 EC091 EC101 EC111 EC121 EC131 EC151 EC161 EC211 EC241 EC261 EC281 GA06 GA14 GA22 HA126 HB17 JA13 KA16 LA05 LA06 LA07 MA01 MA08 MA09 MA10 MB02 MB05 NA12 PA12

Claims (6)

[Claims] 1. An aqueous liquid comprising (A) a vinyl alcohol polymer having a functional group containing active hydrogen in the molecule and (B) an isobutylene-maleic anhydride imide resin having an imide group in the molecule. A two-part adhesive composition comprising one part and a second part containing a water-soluble aldehyde compound. 2. The two-part adhesive composition according to claim 1, wherein the first part further comprises a polyepoxy compound. 3. The two-part adhesive composition according to claim 1, wherein the second part further comprises a polyvalent epoxy compound. 4. The (A) vinyl alcohol polymer having a functional group containing active hydrogen in the molecule is a vinyl alcohol polymer having a primary amino group or a secondary amino group in the molecule. 4. The two-part adhesive composition according to any one of items 1 to 3. 5. The method according to claim 1, wherein (A) the vinyl alcohol polymer having an active hydrogen-containing functional group in the molecule is a vinyl alcohol polymer having an acetoacetyl group in the molecule. Liquid type adhesive composition. 6. Applying a first liquid of the two-part adhesive composition according to claim 1 to a first adherend surface, applying a second liquid to a second adherend surface, A bonding method characterized in that bonding is performed by bringing both application surfaces into close contact with each other.