JP2894862B2 - Building member joining method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for bonding building members such as wall members, floor members, pillar members and the like using an adhesive when producing a building structure such as a house. TECHNICAL FIELD The present invention relates to a method for joining architectural members capable of forming an excellent wall surface or floor surface.

[0002]

2. Description of the Related Art When constructing a building structure such as a house, the joining strength between building members such as wall members and pillar members is important in securing sufficient strength of the entire structure. However, especially in a cold region, not only the strength but also the airtightness between these building members is extremely important in terms of heating efficiency. By the way, when building an architectural structure such as a conventional house, for example, when joining a wall member and a wall member or a pillar member and a wall member, and further, when joining a wall member and a floor member,
Although nails are mainly used to obtain sufficient joint strength,
As described above, simply by nailing, sufficient airtightness cannot be obtained, and in a cold region or the like, a post-process such as applying a tape to a joint or applying a sealing agent is required.

In recent years, improvements in adhesives have been made,
Since a new adhesive having excellent bonding strength has been provided, a construction method using an adhesive instead of a nail has been increasing. The adhesive used in such a method includes, for example, a vinyl acetate emulsion adhesive, a rubber adhesive, and an epoxy adhesive. In addition, urethane resins mainly used as a heat insulating material are well known, because they are used for applications different from those applied to joints such as these adhesives to bond between building members. The urethane resin is usually used in a sealed container together with a volatile gas, and is blended so as to foam and expand immediately when discharged from the container.

[0004]

However, in the method of joining between building members described above, post-processing is necessary in the case of nailing, especially in a cold region, so that the work is troublesome and the shortening is required. There is dissatisfaction that we cannot hope. In addition, in the case of joining with a vinyl acetate emulsion adhesive, a rubber-based adhesive, an epoxy adhesive, etc., since the building members are mainly made of wood or plywood, the adhered surface may not be smooth, and When the members are rubbed each other, the adhesive layer becomes thin, so that a gap is formed between the members after the bonding, whereby the airtightness is impaired. This may cause a problem of causing a loss of heating especially in a cold region. Then, in order to cope with such a problem, conventionally, a post-process such as applying a tape to a joint or applying a sealing agent is performed as in the case of nailing, but in this case, the above-mentioned dissatisfaction cannot be avoided.

Attempts have also been made to use a urethane resin, which is mainly used for a heat insulating material, instead of the above-mentioned adhesive as an adhesive. In this case, however, the resin foams immediately upon discharge from a closed container. When the members are joined together, the foamed adhesive is scraped off, and the adhesive strength is impaired, and the effect of filling the gap between the members is significantly lost, and sufficient airtightness is not obtained. There is such a disadvantage.

The present invention has been made in view of the above circumstances, and an object of the present invention is not only to be able to join building members such as wall members, floor members, and column members with sufficient adhesive strength, but also to provide a simple structure. An object of the present invention is to provide a method for joining building members capable of providing excellent airtightness in construction.

[0007]

Means for Solving the Problems As a result of diligent studies to solve the above-mentioned problems, the present inventor has developed a one-component moisture-curable urethane foam adhesive which foams and cures with moisture instead of a conventional adhesive. The present inventors have found that if the coating is applied to the joint so that the joint is airtight after the joining, a building structure such as a wall surface or a floor surface with excellent airtightness can be provided, and the present invention has been completed. That is, in the method for joining building members according to the present invention, a one-component moisture-curable urethane adhesive which foams and hardens due to moisture is applied to a joint between building members such as a wall member and a floor member at predetermined intervals. There was coated to a hermetically after bonding, after bonding and the joint of the joint and other building components, to be foamed cure the adhesive
The provision of the joining and heat insulating functions is a means for solving the above problem.

Hereinafter, the method for joining building members according to the present invention will be described in detail. The one-component moisture-curable urethane adhesive used in the present invention (hereinafter, abbreviated as urethane adhesive) is
A composition comprising a urethane prepolymer as a main component, a surfactant of 0 to 30 parts by weight, and a thickener or a thixotropic agent of 0.5 to 500 parts by weight per 100 parts by weight of the urethane prepolymer. is there. Here, the urethane polymer is obtained by reacting a polyol (polyhydroxy compound) such as a polyether polyol or a polyester polyol with an excess of a polyisocyanate compound, and contains 1% by weight or more of an active isocyanate group at a molecular terminal. Things. (Hereinafter, this urethane prepolymer is referred to as an NCO group-containing urethane prepolymer.) Further, the surfactant is for uniformly foaming the NCO group-containing urethane prepolymer or for increasing the expansion ratio, and a thickener. (Or thixotropic agent) is for imparting thixotropic properties so that the resulting foamed adhesive does not run down when applied to the vertical surface of the member to be bonded.

A urethane adhesive having such a composition generates carbon dioxide gas when its active isocyanate group (hereinafter referred to as NCO group) reacts with moisture (moisture) in the air or moisture in a member to be bonded. It expands and expands the apparent volume by the expansion, and the expansion due to the expansion starts to be seen in about 30 minutes after the reaction is started by contact with moisture, and is almost finished after about one day has passed. The composition was adjusted. In addition, this urethane adhesive has a foaming ratio at the time of reaction of 1.
The composition is adjusted so as to be 3 to 5 times, preferably 1.5 to 3 times. Here, the reason why the expansion ratio is set to 1.3 to 5 times is that when the ratio is less than 1.3 times, when the building members are bonded to each other, the effect of filling the gaps between the building members due to foam expansion is sufficient. On the other hand, if it exceeds 5 times, the adhesive strength between the members is reduced, and the amount of the adhesive protruding from the joint surface is increased, resulting in a disadvantage that the workability is deteriorated. In order to obtain the expansion ratio of 1.3 to 5 times, the NCO group content in the urethane adhesive needs to be 1% by weight or more.

Examples of the polyol used for synthesizing the NCO group-containing urethane prepolymer include polyoxyethylene polyol, polyoxypropylene polyol, random or block copolymer polyoxyethylene-propylene copolymer polyol, amine compound ( Polyols obtained by ring-opening polymerization of ethylene oxide or propylene oxide with methylamine, ethylamine, propylamine, ethylenediamine, propylenediamine, etc., polyether polyols such as polyoxytetramethylene glycol, dicarboxylic acids (adipic acid, succinic acid) , Maleic acid, phthalic acid, etc.) and glycols (ethylene glycol, propylene glycol, 1,4-butylene glycol, 1,6-hexanediol, neopentyl) And polyester polyols such as polybutylene adipate polyol, polyhexamethylene adipate polyol, and polylactone polyols, which are obtained by polycondensation with polylactone polyols, and usually have a molecular weight of 200 to 20,000. Are used alone or as a mixture. In addition, low molecular weight polyols and polyamines can of course be used, such as polyols such as ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, hexanediol, glycerin, trimethylolpropane, and ethylenediamine; Examples thereof include polyamines such as diphenylmethanediamine and m-phenylenediamine, which are used alone or as a mixture as described above.

The polyisocyanate compound used for the synthesis of the NCO group-containing urethane prepolymer includes, for example, tolylene diisocyanate (TDI),
4,4'-diphenylmethane diisocyanate (MD
I), polymethylene polyphenylene polyisocyanate (polymeric MDI), carbodiimide-modified MDI,
Aromatic polyisocyanates such as naphthalene diisocyanate and hexamethylene diisocyanate (HMD
I), trimethylhexamethylene diisocyanate (T
Aliphatic polyisocyanates such as MDI), isophorone diisocyanate (IPDI), 4,4'-
Dicyclohexylmethane diisocyanate (hydrogenated MD
And alicyclic polyisocyanates such as I).
These compounds are used alone or as a mixture thereof. More preferred polyisocyanate compounds are aromatic polyisocyanates, such as TDI or MDI.

Then, the respective amounts of the NCO groups of the polyisocyanate compound are prepared and reacted so that the NCO groups of the polyisocyanate compound become excessive with respect to the hydroxyl groups of the polyol. Thus, an NCO group-containing urethane prepolymer used in the present invention can be obtained. Here, as described above, when the NCO group content is less than 1% by weight, the degree of foaming is reduced and the effect of filling the voids is reduced.

Further, in the urethane adhesive used in the present invention, as described above, a surfactant can be used to foam the adhesive uniformly or to increase the expansion ratio. As such a surfactant,
Examples thereof include a polysiloxane-polyoxyalkylene block copolymer and a phenolic compound to which ethylene oxide has been added, and 0 to 30 parts by weight, preferably 0.1 part by weight, per 100 parts by weight of the urethane prepolymer containing NCO groups. -10 parts by weight are added. Examples of the thickener (or thixotropic agent) include colloidal silica, finely divided carbon black, fatty acid-treated calcium carbonate, castor oil derivatives, fatty acid amides and fatty acid metal soaps.
It is added in an amount of 0.5 to 500 parts by weight, preferably 1 to 200 parts by weight, based on 100 parts by weight of the NCO group-containing urethane prepolymer.

The urethane adhesive may of course contain an inert solvent, a plasticizer, a filler, a curing accelerating catalyst or other additives as required. Here, the inert solvent is used for adjusting the viscosity, for example, ethyl acetate, ester solvents such as butyl acetate, cellosolve ester solvents such as cellosolve acetate, acetone, ketone solvents such as methyl ethyl ketone,
Solvents having no active hydrogen, such as aromatic hydrocarbon solvents such as benzene, toluene and xylene, and aliphatic or petroleum hydrocarbon solvents such as n-hexane and n-heptane are used.

The plasticizer is used for adjusting the viscosity and physical properties after curing. For example, dioctyl adipate (DOA), dioctyl phthalate (DOP), dibutyl phthalate (DBP), tricresyl phosphate (TCP) ) And oligomer plasticizers such as polyesters and urethanized polyethers. Fillers are used as fillers or reinforcing agents.For example, inorganic fillers such as calcium carbonate, talc, clay, and carbon, organic fillers such as polyvinyl chloride fine powder, and microballoons such as shirasu balloons and glass microballoons are used. Is done.

The curing acceleration catalyst is used for controlling the curing speed of the adhesive, and a catalyst known in polyurethane chemistry can be used. Examples thereof include tin octylate, tin naphthenate, dibutyltin dilaurate, and zinc octylate. Organic acids and metal salts such as Sn, Co, Ni, Fe, Zn, Pb,
Tertiary amines such as 1,4-diaza 2,2,2 bicyclooctane, triethylamine, N, N-dimethylcyclohexylamine, diaza-bicycloundecene, N, N-diethylbenzylamine, triethylenediamine, N-methylmorpholine Are used alone or as a mixture thereof.

Such a urethane adhesive is stably stored in a closed container without being cured. And
In the present invention, the urethane adhesive is applied to joints of building members such as wall members and floor members at predetermined intervals . The application at this time is performed so that the joint is airtight after joining, and thereafter, the joint is joined to a joint of another building member. As a method of applying the urethane adhesive to the building member so that the joint becomes airtight after the joining, a method of applying the joint to the building member in a continuous bead shape, or spreading the entire joint with a spatula or the like A known method such as a method is employed. It is needless to say that the urethane adhesive may be applied to the joints to be joined to the joints in the same manner. The surface to which the urethane adhesive has been applied in this way is joined to the surface to be bonded of another building member, and fixed with nails or the like as necessary.

As building members to be joined, wall members such as wall panels formed by assembling frame materials into a rectangular frame shape and pasting the surface materials on both front and back surfaces or one surface thereof, and further, pillar members and ceiling members, etc. A member located mainly in a portion of the structure where airtightness is required is selected. Further, the present invention can be used not only for the structural material but also for attaching a base material such as a gypsum board, a construction material such as a window frame, and a finishing material. Further, in addition to directly bonding building members to each other, there is also a method of applying a urethane adhesive to the outside of a joint portion and pasting another airtight material such as a vinyl sheet thereon to achieve airtightness. That is, in order to keep the interior of the room airtight, the airtightness of the joint is particularly important.

If the urethane adhesive is applied to such a joint and the building members are joined to each other, the urethane adhesive reacts with the moisture in the air or the moisture contained in the member in the NCO group. And start curing. Then, the urethane adhesive generates a carbon dioxide gas with the curing reaction, and thereby foams and expands to not only perform the bonding but also fill the gaps between the members at the same time, so that the hermeticity (airtightness) is obtained.
Will increase. In addition, since the expansion due to the curing reaction starts to be seen after contact with moisture, that is, about 30 minutes after application, and ends after about 24 hours, the adhesive may be scraped off when the building members are joined together. Not
Also, the joining process can be completed by removing the portion that has expanded and expanded and protruded from the joining portion the next day.

In such a method of joining building members, the urethane adhesive reacts with moisture to cure and foam and expand, so that the gaps between the building members can be filled to improve the airtightness. Also, since the urethane adhesive is a one-component type, there is no need to mix the main agent and the curing agent as in the two-component type, and therefore, it has an excellent effect of being easy to use and not causing poor adhesion and poor foaming due to poor mixing. Play. Furthermore, since the foaming expansion accompanying the curing reaction of the urethane adhesive starts to be seen in about 30 minutes after application and ends in about 24 hours, the adhesive strength and airtightness are impaired by scraping off the adhesive at the time of joining. Without
In addition, since the time until the completion of curing is relatively short, there is no possibility that the construction period will be delayed.

[0021]

Next, the present invention will be described specifically with reference to examples. First, a production example of the urethane adhesive used in the present invention will be described. (Production Example 1) While flowing nitrogen gas into a reaction vessel, 346 parts by weight of polyoxypropylene glycol having an average molecular weight of 3200 and polymeric MDI (MR
-200, manufactured by Nippon Polyurethane Industry Co., Ltd.) and 0.5 parts by weight of zirconium octylate were added to the reaction vessel while stirring them.
The reaction was carried out at a temperature of ~ 90 ° C for 2 hours,
An NCO group-containing urethane prepolymer having 6.0% by weight and a viscosity of 3000 cP (at 25 ° C.) was obtained.

Next, dry calcium carbonate 30 was added to 100 parts by weight of the obtained NCO group-containing urethane prepolymer.
Parts by weight, 0.5 parts by weight of a polysiloxane-polyoxyalkylene block copolymer surfactant (F-305, manufactured by Shin-Etsu Chemical Co., Ltd.) and 5.4 parts by weight of colloidal silica are added, and the mixture is sufficiently supplied with flowing nitrogen gas. After kneading, defoaming was performed under reduced pressure to obtain a light brown paste-like one-component moisture-curable urethane adhesive.

(Production Example 2) A polyoxyethylene-propylene copolymer polyol (Newpol PE-64, having an average molecular weight of 2900 and an ethylene oxide content of 40% by weight) was supplied to the reaction vessel while flowing nitrogen gas into the reaction vessel.
346 parts by weight of Sanyo Kasei Kogyo Co., Ltd. and Polymeric MD
I (the above-mentioned MR-200) 453 parts by weight, 0.5 parts by weight of zirconium octylate was added to the reaction vessel while stirring them, and the mixture was reacted at a temperature of 80 to 90 ° C. for 2 hours. Content 15.5% by weight, viscosity 29
An NCO group-containing urethane prepolymer of 50 cP (at 25 ° C.) was obtained.

Next, dry calcium carbonate 30 was added to 100 parts by weight of the obtained NCO group-containing urethane prepolymer.
After adding 5.4 parts by weight of colloidal silica and sufficiently kneading the mixture under flowing nitrogen gas, the mixture was defoamed under reduced pressure to obtain a one-component moisture-curable urethane adhesive in the form of a pale brown paste.

The one-component moisture-curable urethane adhesive obtained in each of Preparation Examples 1 and 2 was applied to the surface of Yonematsu for 0.1 minute.
Apply to a thickness of 3 mm and use standard conditions (20 ° C, 4
(5 to 65% RH) for 24 hours to cure, and then the thickness of the adhesive layer was measured to obtain the expansion ratio. The expansion ratio was determined by the following equation. Foaming ratio = (thickness of adhesive layer after curing) ÷ 0.3

The one-component moisture-curable urethane adhesive is applied to one of the adherends, Yonematsu, to a thickness of 0.3 mm, and the gap between the surfaces to be adhered becomes 0.6 mm. The other Yonematsu, which is to be the adherend, was fixed with the spacers interposed therebetween as described above, and allowed to stand for 7 days in a standard state to be cured by reaction, and then the compression shear adhesive strength was measured. Measurement is JIS K6
852 (1976). Table 1 shows the obtained measurement results.

[0027] The unit of the compressive shear adhesive strength in Table 1 is (kgf / c
m ² ). From the results shown in Table 1, the urethane adhesives obtained in Production Examples 1 and 2 have a foaming ratio of 2.0 to 2.5 after 24 hours and fill the voids when joining between building members. It was confirmed that the magnification was suitable. In addition, it was confirmed that the composition had a compressive shear bond strength required for bonding between building members.

Next, using the urethane adhesive thus obtained, it is applied and adhered between building members such as walls and floors so that the joints are airtight after joining. It was fabricated experimentally and its airtight state was examined. Here, as for building members such as walls and floors, wall panels and floor panels assembled in advance in factories and the like were used. Further, for comparison, each building member was adhered to each other with a conventional vinyl acetate emulsion adhesive using a wall panel, a floor panel, and the like, a similar room was produced, and the airtight state was examined by the same method. Furthermore, without using a wall panel and a floor panel, a room is made by a conventional method of joining each member by nailing,
The airtightness was examined by the same method.

When the airtightness of one room based on the three methods was examined in this manner, the airtightness of one room produced by the method of the present invention was determined using a wall panel, a floor panel, and the like. Approximately 4 rooms per room made with adhesive
It was confirmed that the airtight state was maintained twice as high as that of the conventional method by about 20 times.

[0030]

As described above, in the method of joining building members according to the present invention, a one-component moisture-curable urethane adhesive foamed and cured by moisture is applied to a building member such as a wall member or a floor member at a predetermined interval. The joints are applied to each other so that the joints are air-tight after joining, and after joining the joints and the joints of other building members, the adhesive is foamed and cured, thereby joining and joining. Because it is a construction method that imparts a heat insulating function , the urethane adhesive reacts with moisture and cures and foams and expands. It can be buried out of circulation to increase its airtightness. Therefore, if this method is applied to the construction of a house especially in a cold region, the air does not circulate through the joint, so that the heating efficiency of the house can be improved. Also, since the urethane adhesive is a one-component type, there is no need to mix the main agent and the curing agent as in the two-component type. Therefore, the urethane adhesive is easy to use and does not cause poor bonding and poor foaming due to poor mixing. It can be easily implemented without requiring. Further, since the curing reaction of the urethane adhesive starts after coming into contact with moisture and foaming expansion occurs with this, the foaming expansion does not occur immediately after being applied to a building member, and thus the adhesive is scraped off at the time of joining. By doing so, it is possible to avoid such inconvenience that the adhesive strength between the building members and the airtightness are impaired.

Claims (1)

(57) [Claims] 1. A one-component moisture-curable urethane adhesive which foams and cures with moisture at a joint between building members such as a wall member and a floor member provided at a predetermined interval, and the joint becomes airtight after joining. After coating and joining the joint and the joint of other building members, the adhesive is foamed and cured to provide a joint and heat insulating function.
A method of joining building members.