JP2006316133A - Two-pack curable aqueous adhesive - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-pack curable aqueous adhesive capable of ensuring sufficient closed deposition time on operation when bonding woody materials and exhibiting excellent adhesive force in a short pressing time. <P>SOLUTION: The two-pack curable aqueous adhesive is composed of a liquid (A) and a liquid (B). The liquid (A) is an aqueous solution or an aqueous emulsion containing a polymer compound (A1) having an acetoacetyl group in the molecule. The liquid (B) is a hydrazide group-containing polymer having an unsubstituted or mono-substituted carbamoyl group and/or hydrocarbon-oxy-carbonyl group on the side chain in the molecule and having a hydrazide group on the side chain in the molecule. A (meth)acrylic acid hydrazide-based polymer (B1) which is a reaction product of a (meth)acrylamide-based polymer and/or a (meth)acrylic acid ester-based polymer (B1-a) with hydrazine (B1-b) can suitably be used as the hydrazide group-containing polymer (B). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a two-part curable water-based adhesive, and more specifically, is less susceptible to the influence of air temperature and material temperature when adhering a wooden material, and can ensure a sufficient closed deposition time for work. The present invention relates to a two-component curable aqueous adhesive that can exhibit excellent adhesive force even in a short pressing time.

  In general, “It is the time from applying the adhesive to a predetermined surface of the adherends, stacking the adherends on top of each other and depositing them, and starting to press the adherends. The time allowed for starting the pressing so that it can be bonded is referred to as the “deposition time”. In particular, “the adhesive is applied to a predetermined surface of the adherend and then covered. It is the time to leave the materials in the air until they are stacked and deposited. After the materials are stacked and deposited, it is possible to adhere the adherends together. The time allowed to start pressing is referred to as “open deposition time”, and “adhesive is applied to a predetermined surface of the adherend and the adherends are overlapped. It is the time from the start of deposition to the start of pressing, and the adherends are brought into close contact with each other. It referred to as "closed deposition time" the time allowed "when starting the pressing so capable. “Adhesive is applied to a predetermined surface of an adherend, the adherends are stacked and stacked, and after being pressed, it is the time from release to press, The “time allowed for continuing the pressing so that the two can be brought into close contact with each other” is referred to as “pressing time”.

  Therefore, the deposition time that is the time from application of the adhesive to pressing is an open deposition time that is the time from application of the adhesive to deposition of the adherends, It includes a closed deposition time, which is the time from when the adherends are deposited on top of each other until they are pressed together. The pressing time, which is the time from the start of pressing until the pressure is released (pressing curing time), is continued after the deposition time or the closed deposition time.

  Wood material boards (flash panels, etc.) on which wood materials are stacked are produced by stacking and stacking wood materials, and pressing and firmly bonding them. Conventionally, when bonding wood materials, acetic acid has been used. A wood-based water-based adhesive mainly composed of a vinyl emulsion (sometimes referred to as “wood-vinegar emulsion-based water-based adhesive for woodwork”) has been widely used. This water-based vinyl chloride emulsion adhesive for woodworking is a mechanism that hardens when moisture is diffused in the adherend because the mechanism of adhesiveness is manifested. There is a drawback of being greatly affected. Specifically, in summer (for example, when the temperature is 30 ° C.), the closed deposition time (that is, it is allowed to start pressing so that the adherends can be brought into close contact with each other). Time), and the pressing time (that is, the time allowed to continue pressing so that the adherends can be brought into close contact with each other) are shortened. In the case where the temperature is 5 ° C.), on the contrary, the closed deposition time and the pressing time become long, and the difference between them is extreme, so that it is difficult to set a stable working time.

  In order to improve such drawbacks, for example, a first liquid [(A liquid)] containing an acetoacetyl group-containing polymer compound and a second liquid [(B) liquid containing a hydrazine compound are used as an aqueous woodworking adhesive. A method using a two-component fractional application type water-based adhesive comprising the following is employed (see Patent Document 1). Also proposed is a two-component fractional application type aqueous adhesive comprising a first liquid [(A liquid)] containing a resin emulsion and acetoacetylated polyvinyl alcohol and a second liquid [(B) liquid] containing a hydrazine derivative. (See Patent Document 2). Since these two-component fractionation-applying water-based adhesives are mechanisms that cure due to a chemical reaction, the adhesive is less susceptible to the influence of temperature and material temperature. However, since such a conventional two-component fractional application type water-based adhesive is a fast curing type (instant curing type), a low molecular weight hydrazide compound such as adipic acid dihydrazide is usually used as the hydrazine compound. Yes. Therefore, this two-component fractional application type water-based adhesive has a high gelation speed. For example, using the (B) solution containing a low molecular weight hydrazide compound as a primer component, When the primer application surface and the main agent application surface are brought into contact with each other after the application to the attachment surface, (A) liquid is used as the main agent, and the other application surface is applied, the gelation proceeds immediately. The allowable closed deposition time until (pressing) is very short, which is difficult in terms of workability.

  In addition, in adhesion of a wood material, water resistance is often required, and in this case, an adhesive of an aqueous polymer-isocyanate compound (sometimes referred to as “aqueous polymer-isocyanate adhesive”). Is used. This water-based polymer-isocyanate-based adhesive also has a drawback that it is greatly affected by the air temperature and material temperature, as in the case of the vinyl acetate emulsion-based water-based adhesive for woodworking.

  Furthermore, the conventional aqueous polymer-isocyanate adhesive does not peel off the adhesive layer after the pressure is released, and meets the standard of JAS structural laminated materials that require high water resistance as the final adhesion performance. For this purpose, a pressing time of 30 minutes or more is required, the pressing time is very long, and productivity is low.

  For this reason, in the production of wood material plates with laminated wood materials such as flash panels, when wood materials are bonded, they are less susceptible to the effects of air temperature and material temperature, and furthermore, a sufficient closed deposition time is ensured in the work. In addition, there is a need for a two-component curable aqueous adhesive (particularly a two-component fractional application-type aqueous adhesive) that can exhibit excellent adhesion even with a short pressing time.

Japanese Patent Publication No. 1-60192 Japanese Patent No. 3181048

  Therefore, for example, in a two-component fractional coating type aqueous adhesive comprising a first liquid containing an acetoacetyl group-containing polymer compound and a second liquid containing a hydrazine compound, an isocyanate compound is used as the third liquid. A first liquid [(A) liquid] containing an acetoacetyl group-containing polymer compound in which an isocyanate compound as three liquids is blended to improve water resistance, and a second liquid [(B) liquid] containing a hydrazine compound; A method using a two-component fractional coating type water-based adhesive comprising However, since the conventional two-component fractional application type water-based adhesive is a fast-curing type, the closed deposition time is short, and the wood material is adhered in the production of the wood material plate on which the wood material such as a flash panel is superimposed. However, it has been difficult to secure a sufficient closed deposition time for work. Therefore, when bonding wood materials, a two-component curing type that can secure a sufficient closed deposition time for work and can exhibit excellent adhesive force even with a short pressing time. The present condition is that the water-based adhesive (especially 2 liquid fraction application type water-based adhesive) is not developed.

  In addition, since the conventional two-component fractional application type water-based adhesive is a fast curing type (instant curing type), a low molecular weight hydrazide compound is used as described above, and usually a high molecular weight hydrazide compound is Not used. Therefore, even if an example of a polymer containing a hydrazide group is given as the hydrazide compound, the polymer containing a hydrazide group has a low molecular weight (for example, less than 10,000) in order to exhibit fast curability. This is very important.

Therefore, the object of the present invention is to be less affected by the air temperature and material temperature when adhering the wood material, and can ensure a sufficient closed deposition time for work, and even with a short pressing time, An object of the present invention is to provide a two-component curable aqueous adhesive capable of exhibiting excellent adhesive force.
Another object of the present invention is to provide a two-component curable aqueous adhesive that can exhibit excellent water resistance.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have determined that a two-component fractional application-type aqueous adhesive using an aqueous solution or aqueous emulsion of an acetoacetyl group-containing polymer compound as the first liquid [liquid (A)]. In the above, it has been found that when a compound containing a specific hydrazide group is used as the second liquid [liquid (B)], the closed deposition time and the pressing time can be controlled. The present invention has been completed based on these findings.

That is, the present invention is a two-component curable aqueous adhesive comprising the following (A) solution and (B) solution.
(A) An aqueous solution or aqueous emulsion containing a polymer compound (A1) having an acetoacetyl group in the molecule (B) An unsubstituted or monosubstituted carbamoyl group and / or hydrocarbon-oxy-carbonyl on the side chain in the molecule And hydrazide group-containing polymer having a hydrazide group in the side chain in the molecule

  In the two-component curable aqueous adhesive of the present invention, the hydrazide group-containing polymer (B) preferably has a skeleton or main chain formed by polymerization of a monomer component having an ethylenically unsaturated bond. The hydrazide group-containing polymer (B) is a reaction product of (meth) acrylamide polymer and / or (meth) acrylate polymer (B1-a) and hydrazine (B1-b) (meth). An acrylic acid hydrazide polymer (B1) can be preferably used.

  As the polymer compound (A1) having an acetoacetyl group in the molecule, modified polyvinyl alcohol having an acetoacetyl group in the molecule can be suitably used. The aqueous solution or aqueous emulsion (A) containing the polymer compound (A1) may further contain an isocyanate compound (A2).

  The two-component curable aqueous adhesive of the present invention may be a two-component fractional application type aqueous adhesive.

  The present invention is also a method of adhering an adherend using a two-component curable aqueous adhesive, wherein the two-component curable aqueous adhesive is used as the two-component curable aqueous adhesive, and Applying an aqueous solution or aqueous emulsion (A) to the surface of one adherend and applying a hydrazide group-containing polymer (B) to the surface of the other adherend to bond the two adherends A method for adhering an adherend using a two-component curable aqueous adhesive is provided.

  The two-part curable water-based adhesive of the present invention is less susceptible to the influence of air temperature and material temperature when adhering a wooden material, and can ensure a sufficient closing accumulation time for work, and can have a short pressing time. Even if it exists, the outstanding adhesive force can be exhibited. Furthermore, excellent water resistance can be exhibited. Therefore, by using the two-component curable water-based adhesive, it is possible to manufacture a wood material board on which wood materials such as flash panels are superimposed with excellent productivity.

[(A) liquid]
In the present invention, as the first liquid [(A) liquid] in the two-component curable aqueous adhesive, an acetoacetyl group [acetyl-acetyl group; CH ₃ —C (═O) —CH ₂ —C (= An aqueous solution or an aqueous emulsion (A) containing the polymer compound (A1) having O)-] (sometimes referred to as “acetoacetyl group-containing polymer compound (A1)”) is used. (A) The acetoacetyl group-containing polymer compound (A1) in the liquid is a hydrazide group that is used as the second liquid [liquid (B)] in a two-part curable aqueous adhesive using an acetoacetyl group. A crosslinking reaction proceeds by reacting with the containing polymer (B), and the adhesiveness of the two-component curable aqueous adhesive is expressed by this crosslinking reaction.

(Acetoacetyl group-containing polymer (A1))
The acetoacetyl group-containing polymer compound (A1) is not particularly limited as long as it is a polymer compound having at least one acetoacetyl group in the molecule. In the acetoacetyl group-containing polymer compound (A1), it is sufficient that at least one acetoacetyl group is contained in the polymer compound, for example, in the main chain of the polymer chain (inside of the main chain or at the end). ) Or in the side chain (inside or at the end of the side chain). The acetoacetyl group-containing polymer compound (A1) preferably has an acetoacetyl group at the end of the main chain or the end of the side chain, and particularly preferably at the end of the side chain. .

  More specifically, as the acetoacetyl group-containing polymer compound (A1), for example, a water-soluble polymer compound (for example, polyvinyl alcohol; hydroxyalkyl cellulose such as hydroxyethyl cellulose; hydroxyl group-containing water-soluble polymer such as starch) A water-soluble polymer compound obtained by acetoacetylating a molecular compound or the like by a known method, or an acetoacetyl group-containing monomer [for example, acetoacetoxymethyl (meth) acrylate, 2-acetoacetoxyethyl (meth) acrylate, 2-acetoacetoxy Acetoacetoxyalkyl (meth) acrylates such as propyl (meth) acrylate, 3-acetoacetoxypropyl (meth) acrylate, 4-acetoacetoxybutyl (meth) acrylate; vinyl acetoacetate; allyl aceto Corresponding (derived) and the like] Seteto water-soluble polymer compound containing a constitutional unit (repeating unit) and the like. In addition, an acetoacetyl group containing high molecular compound (A1) can be used individually or in combination of 2 or more types.

  As the acetoacetyl group-containing polymer compound (A1), for example, modified polyvinyl alcohol having an acetoacetyl group in the molecule (acetoacetylated polyvinyl alcohol), modified hydroxyalkyl cellulose having an acetoacetyl group in the molecule (acetoacetylated) Hydroxyalkyl cellulose), water-soluble polymer compounds having an acetoacetyl group in the molecule (acetoacetylated water-soluble polymer compound) such as starch having an acetoacetyl group in the molecule (acetoacetylated starch) Among them, acetoacetylated polyvinyl alcohol can be preferably used.

  The acetoacetylated polyvinyl alcohol is a modified polyvinyl alcohol (acetoacetyl-modified polyvinyl alcohol) in which a hydrogen atom in a hydroxyl group in polyvinyl alcohol is modified to an acetoacetyl group. In the acetoacetylated polyvinyl alcohol, the degree of acetoacetylation (degree of acetoacetylation modification) in the molecule is not particularly limited, and can be selected, for example, from a range of about 0.1 to 20 mol%, preferably Is about 2 to 20 mol% (particularly 3 to 10 mol%). If the degree of acetoacetylation in the molecule of the acetoacetylated polyvinyl alcohol is less than 2 mol%, the reaction between the acetoacetylated polyvinyl alcohol and the hydrazino group-containing amide compound (B) is delayed, while 20 mol% Exceeding this causes problems in terms of the solubility of acetoacetylated polyvinyl alcohol and makes it difficult to prepare a two-part curable aqueous adhesive composition.

  Moreover, the polymerization degree of acetoacetylated polyvinyl alcohol is not particularly limited, and can be selected, for example, from a range of about 200 to 3000 (preferably 500 to 2500, more preferably 1000 to 2000).

  Furthermore, in the acetoacetylated polyvinyl alcohol, the saponification degree is not particularly limited, and can be selected from the range of, for example, about 80 to 100 mol% (preferably 85 to 98 mol%). As the acetoacetylated polyvinyl alcohol, a plurality of acetoacetylated polyvinyl alcohols having different saponification degrees can be mixed and used.

  The method for preparing acetoacetylated polyvinyl alcohol is not particularly limited, and examples thereof include known methods for reacting polyvinyl alcohol with diketene and the like. As such acetoacetylated polyvinyl alcohol, for example, the product name “Gosefimmer Z100”, the product name “Gosefimmer Z200”, the product name “Gosefimmer Z200H”, the product name “ The “GOHSEPIMAR Z210”, the product name “GOHSEFIMAR Z220”, the product name “GOHSEPHIMER Z320”, and the like are commercially available.

(Aqueous solution containing acetoacetyl group-containing polymer (A1))
In the liquid (A), the aqueous solution containing the acetoacetyl group-containing polymer compound (A1) (sometimes referred to as “aqueous solution (A)”) is a polymer having at least one acetoacetyl group in the molecule. The aqueous solution containing the compound is not particularly limited. As the acetoacetyl group-containing polymer compound (A1) in the aqueous solution (A), the acetoacetyl group-containing polymer compound (A1) exemplified above (for example, acetoacetylated polyvinyl alcohol, acetoacetylated hydroxyalkyl cellulose, aceto Acetoacetylated water-soluble polymer compounds such as acetylated starch) can be appropriately selected and used.

  When acetoacetylated polyvinyl alcohol is used as the acetoacetyl group-containing polymer compound (A1), ordinary polyvinyl alcohol that is not acetoacetylated is added (blended) to the aqueous solution (A). It is also possible to improve workability and the like.

  As for aqueous solution (A), only 1 type may be used and 2 or more types may be used in combination.

(Aqueous emulsion containing acetoacetyl group-containing polymer (A1))
On the other hand, in the liquid (A), the aqueous emulsion containing the acetoacetyl group-containing polymer compound (A1) (sometimes referred to as “aqueous emulsion (A)”) has at least one acetoacetyl group in the molecule. There is no particular limitation as long as it is an aqueous emulsion containing a polymer compound. The acetoacetyl group-containing polymer compound (A1) in the aqueous emulsion (A) can be appropriately selected from the exemplified acetoacetyl group-containing polymer compound (A1). The containing form of the acetoacetyl group-containing polymer compound (A1) in the aqueous emulsion (A) is not particularly limited. For example, in the aqueous emulsion (A), the acetoacetyl group-containing polymer compound (A1) may be contained in the aqueous emulsion (A) by being used as an emulsifier, and the main polymer component constituting the emulsion particles May be contained in the aqueous emulsion (A).

  When the acetoacetyl group-containing polymer compound (A1) is used as an emulsifier in the aqueous emulsion (A), examples of the acetoacetyl group-containing polymer compound (A1) include acetoacetylated polyvinyl alcohol and acetoacetylated compounds. Hydroxyalkyl cellulose, acetoacetylated starch and the like can be used. In this case, examples of the main component constituting the emulsion particles include resin components such as vinyl acetate resin, ethylene-vinyl acetate resin, and acrylic resin, and rubber components such as styrene-butadiene rubber. That is, as the aqueous emulsion (A), various resin emulsions in which the acetoacetyl group-containing polymer compound (A1) is used as an emulsifier (for example, polyvinyl acetate emulsion, ethylene-vinyl acetate resin emulsion, acrylic resin emulsion, etc.) And rubber latex (for example, styrene-butadiene rubber latex) in which the acetoacetyl group-containing polymer compound (A1) is used as an emulsifier.

  In the aqueous emulsion (A), when the acetoacetyl group-containing polymer compound (A1) is used as the main polymer component constituting the emulsion particles, the acetoacetyl group-containing polymer compound (A1) is, for example, Water-soluble compounds containing structural units corresponding to acetoacetylated water-soluble polymer compounds (for example, acetoacetylated polyvinyl alcohol) and monomers having at least one acetoacetyl group in the molecule (acetoacetyl group-containing monomers) A high molecular compound etc. can be used. Accordingly, in the aqueous emulsion (A), the acetoacetyl group-containing polymer compound (A1) is emulsified as necessary using an emulsifier (for example, a surfactant, an acid, an alkali, etc.), a resin emulsion, or the like. And aqueous emulsions. The emulsifier and the resin emulsion are not particularly limited, and can be appropriately selected from known emulsifiers and resin emulsions. For example, as resin emulsion, vinyl acetate resin emulsion (polyvinyl acetate emulsion, ethylene-vinyl acetate resin emulsion, etc.), acrylic resin emulsion (acrylic ester copolymer resin emulsion, etc.), rubber latex (styrene-butadiene series) Resin emulsion, etc.). The resin emulsion such as vinyl acetate resin emulsion and acrylic resin emulsion may be an emulsion polymer or an emulsion obtained by emulsifying a polymer obtained by solution polymerization or the like.

  In the acetoacetyl group-containing polymer compound (A1) in the aqueous emulsion (A), the water-soluble polymer compound containing a structural unit corresponding to the acetoacetyl group-containing monomer includes an acetoacetyl group-containing monomer, Accordingly, a water-soluble polymer compound obtained by polymerization (particularly emulsion polymerization) with a monomer copolymerizable with the acetoacetyl group-containing monomer (sometimes referred to as “copolymerization monomer”) can be suitably used. . Examples of the acetoacetyl group-containing monomer include the acetoacetyl group-containing monomers exemplified above. The acetoacetyl group-containing monomer can be used alone or in combination of two or more.

  The copolymerization monomer is not particularly limited as long as it is a monomer copolymerizable with an acetoacetyl group-containing monomer, and for example, various ethylenically unsaturated monomers can be used. Examples of the copolymerizable monomer include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, and isobutyl (meth) acrylate. , S-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ( Isooctyl acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, tetradecyl (meth) acrylate, hexadecyl (meth) acrylate, (meth) ) Acrylic monomers such as octadecyl acrylate; styrene, vinyl tolue Styrene monomers such as α-methylstyrene; vinyl esters such as vinyl acetate and vinyl propionate; vinyl halides such as vinyl chloride and vinylidene chloride; vinyl ethers such as methyl vinyl ether; (meth) acrylic acid and itacon Carboxylic group-containing vinyl monomers such as acid, crotonic acid, maleic acid, fumaric acid and maleic anhydride; Cyano group-containing vinyl monomers such as acrylonitrile and methacrylonitrile; Hydroxyl groups such as hydroxyethyl (meth) acrylate -Containing vinyl monomers; epoxy group-containing vinyl monomers such as glycidyl (meth) acrylate; amide group-containing vinyl monomers such as N-methylol (meth) acrylamide; N, N-dimethylamino (meth) acrylate Ethyl, aminoethyl (meth) acrylate, (meth ) Amino group-containing vinyl monomers such as t-butylaminoethyl acrylate; alkoxy group-containing vinyl monomers such as methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate; N-vinylpyrrolidone, N- Heterocycle-containing vinyl monomers such as vinyl pyridine, N-vinyl piperidone, N-vinyl pyrimidine, N-vinyl piperazine, N-vinyl pyrazine, N-vinyl pyrrole, N-vinyl imidazole, N-vinyl oxazole, N-vinyl morpholine Olefins and dienes such as ethylene, propylene, isoprene, butadiene, and isobutylene; A copolymerizable monomer can be used individually or in combination of 2 or more types.

  In addition, the water-soluble polymer compound containing the structural unit corresponding to the acetoacetyl group-containing monomer may be at least partially saponified when vinyl acetate is used as the copolymerizable monomer component.

  Thus, in the present invention, the aqueous emulsion (A) used as the liquid (A) is obtained by emulsion of a polymer or emulsion polymerization of a monomer using (1) an acetoacetyl group-containing polymer compound (A1) as an emulsifier. And (2) an aqueous emulsion of a water-soluble polymer compound obtained by polymerization (especially emulsion polymerization) of an acetoacetyl group-containing monomer and, if necessary, a copolymerization monomer. Moreover, what combined these 2 or more types may be used. That is, only one type of aqueous emulsion (A) may be used, or two or more types may be used in combination.

  As the aqueous emulsion (A), various resin emulsions (especially acrylic resin emulsions) in which the acetoacetyl group-containing polymer compound (A1) is used as an emulsifier are suitable.

  The liquid (A) is an aqueous solution or an aqueous emulsion containing an acetoacetyl group-containing polymer compound (A1), an aqueous solution containing an acetoacetyl group-containing polymer compound (A1), an acetoacetyl group-containing polymer compound ( An aqueous emulsion containing A1) may be combined.

  (A) Although it does not restrict | limit especially as a density | concentration (solid content concentration) of the acetoacetyl group containing high molecular compound (A1) in a liquid, For example, it selects from the range of 1-25 mass% (preferably 3-10 mass%). can do. When the concentration of the acetoacetyl group-containing polymer compound (A1) is less than 1% by mass with respect to the total amount of the liquid (A), the reactivity with the hydrazide group-containing polymer (B) decreases, and the initial adhesive strength On the other hand, if it exceeds 25% by mass, the viscosity of the entire liquid (A) becomes high, and workability such as difficulty in coating decreases.

  When the (A) liquid is an aqueous emulsion containing the acetoacetyl group-containing polymer compound (A1), the solid content concentration in the (A) liquid is 60% by mass or less (for example, 10 to 60% by mass, Preferably it is 15-40 mass%, More preferably, it is 15-30 mass%.

  In the present invention, in the aqueous solution or aqueous emulsion (A) containing the acetoacetyl group-containing polymer compound (A1) as the liquid (A), acid, alkali, surfactant (cationic surfactant, In addition to emulsifiers such as anionic surfactants and amphoteric surfactants) and resin emulsions (such as the resin emulsions exemplified above), fillers (kaolin, talc, clay, calcium carbonate, etc.), plasticizers, and colorants , Preservatives, rust inhibitors, fungicides, viscosity modifiers, wetting accelerators, viscosity modifiers, perfumes and other known additives may be included, and aqueous organic solvents (for example, methanol , Alcohols such as ethanol, glycol ethers, and the like).

  (A) The preparation method of the aqueous solution or emulsion (A) containing the acetoacetyl group-containing polymer compound (A1) as a liquid is not particularly limited, and the type of the acetoacetyl group-containing polymer compound (A1), It can select suitably according to containing forms, such as an aqueous solution or an aqueous emulsion. Moreover, the aqueous solution or aqueous emulsion containing the commercially available acetoacetyl group containing polymer compound (A1) can also be used. In addition, when using an emulsifier, a resin emulsion, various additives, the isocyanate compound (A2) shown below, etc., these may be used at an appropriate stage (for example, during preparation of an aqueous solution or aqueous emulsion, or after preparation). ) Can be blended.

(Isocyanate compound (A2))
In the present invention, the isocyanate compound (A2) may be further contained in the aqueous solution or aqueous emulsion (A) containing the acetoacetyl group-containing polymer compound (A1) as the liquid (A). By blending the isocyanate compound (A2) into the aqueous solution or the aqueous emulsion (A), the water resistance and initial adhesive strength of the two-component curable aqueous adhesive can be improved. As such an isocyanate compound (A2), for example, polyisocyanate compounds such as aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic polyisocyanate, and araliphatic polyisocyanate can be used. An isocyanate compound (A2) can be used individually or in combination of 2 or more types.

  Examples of the aliphatic polyisocyanate include 1,3-trimethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,3-pentamethylene diisocyanate, 1,5-pentamethylene diisocyanate, 1,6-hexa Methylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, 2-methyl-1,5-pentamethylene diisocyanate, 3-methyl -1,5-pentamethylene diisocyanate, 2,4,4-trimethyl-1,6-hexamethylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 2,6-diisocyanate methyl caproate Lysine diiso Ane - and aliphatic diisocyanates such as bets and the like.

  Examples of the alicyclic polyisocyanate include 1,3-cyclopentane diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate, 4,4. '-Methylenebis (cyclohexyl isocyanate), methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 1,3-bis (isocyanate methyl) cyclohexane, 1,4-bis (isocyanate methyl) cyclohexane, isophorone diisocyanate And alicyclic diisocyanates such as norbornane diisocyanate.

  Examples of aromatic polyisocyanates include m-phenylene diisocyanate, p-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, and naphthylene. 1,4-diisocyanate, naphthylene-1,5-diisocyanate, 4,4'-diphenyl diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane Isocyanate, 4,4'-diphenyl ether diisocyanate, 2-nitrodiphenyl-4,4'-diisocyanate, 2,2'-diphenylpropane-4,4'-diisocyanate, 3, 3'-dimethyldiphenylmethane-4,4'-diisocyanate, 4,4'-diphenylpropane diisocyanate, 3,3'-dimethoxydiphenyl-4, And aromatic diisocyanates such as 4'-diisocyanate.

  Examples of the araliphatic polyisocyanate include 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, ω, ω′-diisocyanate-1,4-diethylbenzene, 1,3-bis. Aroaliphatic diisocyanates such as (1-isocyanate-1-methylethyl) benzene, 1,4-bis (1-isocyanate-1-methylethyl) benzene, 1,3-bis (α, α-dimethylisocyanatomethyl) benzene Etc.

  In the present invention, the isocyanate compound (A2) is a dimer or trimer based on the above-described aliphatic polyisocyanate, alicyclic polyisocyanate, aromatic polyisocyanate, or araliphatic polyisocyanate. , Reaction products or polymers (eg diphenylmethane diisocyanate dimers and trimers, reaction products of trimethylolpropane and tolylene diisocyanate, reaction products of trimethylolpropane and hexamethylene diisocyanate, polymethylene Polyphenyl isocyanate, polyether polyisocyanate, polyester polyisocyanate, etc.) can also be used.

  As the compounding amount of the isocyanate compound (A2) increases, the water resistance improves. However, the isocyanate compound (A2) is required to have a water resistance of “Class 2 or higher of Japanese Agricultural Standards for special plywood”. Often used. Thus, when using an isocyanate compound (A2), as addition amount of an isocyanate compound (A2), it is 1-30 with respect to 100 mass parts of acetoacetyl group containing high molecular compound (A1) in (A) liquid. It can select from the range of a mass part (preferably 5-20 mass parts), and it is preferable that it is about 15 mass parts. When the proportion of the isocyanate compound (A2) is less than 1 part by mass with respect to 100 parts by mass of the acetoacetyl group-containing polymer compound (A1), the effect of improving water resistance is small, whereas it exceeds 30 parts by mass. In this case, restrictions such as shortening the usable time occur and workability is reduced.

  The isocyanate compound (A2) is considered to be involved in the crosslinking of the acetoacetyl group-containing polymer compound (A1) by reacting with the hydrazide group in the hydrazide group-containing polymer (B) in the liquid (B). It is.

[(B) Liquid]
In the present invention, as the second liquid [(B) liquid] in the two-component curable aqueous adhesive, an unsubstituted or monosubstituted carbamoyl group [“—C (═O) —NHR” (R Is a hydrogen atom or a hydrocarbon group)], and / or a hydrocarbon-oxy-carbonyl group [“—C (═O) —OR ′” (R ′ is a hydrocarbon group)], Using a hydrazide group-containing polymer having a hydrazide group [“—C (═O) —NH—NH ₂ ”; carbazoyl group] on the side chain in the molecule (sometimes referred to as “hydrazide group-containing polymer (B)”) ing. In the hydrazide group-containing polymer (B), the hydrazide group reacts with the acetoacetyl group (particularly, the terminal acetyl group) in the acetoacetyl group-containing polymer compound (A1) in the liquid (A). The polymer compound (A1) is crosslinked.

  The hydrocarbon group as R in the formula “—C (═O) —NHR” or R ′ in the formula “—C (═O) —OR ′” is not particularly limited, and examples thereof include an alkyl group, Examples include an aryl group (such as a phenyl group) and a cycloalkyl group (such as a cyclohexyl group), and an alkyl group is preferable. The alkyl group is not particularly limited, and may be, for example, an alkyl group having 1 to 20 carbon atoms. However, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, s -A lower alkyl group such as a butyl group, t-butyl group, pentyl group, hexyl group [preferably an alkyl having 1 to 4 carbon atoms (more preferably 1 to 3 carbon atoms, especially 1 or 2 carbon atoms). Group] is preferred. The hydrocarbon group as R or R ′ may be only one kind, or two or more kinds may be combined.

  The hydrazide group-containing polymer (B) has at least one unsubstituted or monosubstituted carbamoyl group and / or hydrocarbon-oxy-carbonyl group in the side chain in the molecule, and at least a hydrazide group in the side chain in the molecule. The polymer is not particularly limited as long as it has one hydrazide group-containing polymer. A hydrazide group containing polymer (B) can be used individually or in combination of 2 or more types. In such a hydrazide group-containing polymer (B), the number of unsubstituted or monosubstituted carbamoyl groups and / or hydrocarbon-oxy-carbonyl groups in one molecule and the number of hydrazide groups in one molecule are as follows: If it is 1 or more, it will not restrict | limit in particular, According to the polymerization degree (or weight average molecular weight) of a hydrazide group containing polymer (B), a hydrazide conversion rate, etc., it can select suitably. The number of hydrazide groups in one molecule is preferably 2 or more.

  It is important that the hydrazide group-containing polymer (B) does not have an amide bond site (“—NHCO—” bond site) in the skeleton or main chain.

  In the present invention, the hydrazide conversion rate (carbazoyl group conversion rate) of the hydrazide group-containing polymer (B) is 25 mol% or more (preferably 30 mol% or more, more preferably 35 mol% or more, particularly 40 mol% or more). It can be suitably selected from the range. The upper limit of the hydrazide conversion rate of the hydrazide group-containing polymer (B) is not particularly limited as long as it has an unsubstituted or mono-substituted carbamoyl group and is less than 100 mol%. For example, it is desirable that it is 98 mol% or less (preferably 90 mol% or less, more preferably 85 mol% or less, especially 70 mol% or less). When the hydrazide conversion ratio of the hydrazide group-containing polymer (B) is less than 25 mol%, the adhesive strength of the two-component curable aqueous adhesive is lowered.

  In the present invention, the hydrazide conversion rate (mol%) of the hydrazide group-containing polymer (B) is based on the total number of moles of repeating units (structural units or monomer units) constituting the hydrazide group-containing polymer (B). , Means the ratio (mol%) of the number of moles of repeating units (constituent units or monomer units) having a hydrazide group.

The hydrazide conversion rate (mol%) of the hydrazide group-containing polymer (B) can be determined using a redox titration method. Specifically, the hydrazide group-containing polymer (B) includes, for example, a monomer unit having a hydrazide group (molecular weight: M _h ) as a monomer unit and a monomer unit having an unsubstituted or mono-substituted carbamoyl group (molecular weight: M _a). ), The hydrazide conversion rate (mol%) of the hydrazide group-containing polymer (B) can be determined as follows. Of course, the hydrazide conversion rate (mol%) can be similarly determined for the other hydrazide group-containing polymer (B).

First, a hydrazide group-containing polymer (B) [having a monomer unit having a hydrazide group (molecular weight: M _h ) and a monomer unit having an unsubstituted or mono-substituted carbamoyl group (molecular weight: M _a ) as a monomer unit The hydrazide group-containing polymer (B)] is accurately weighed with a mass of about 0.1 g (mass: W), placed in an iodine flask, 80 ml of deionized water is added, and the hydrazide group-containing polymer (B ) Is dissolved in deionized water to prepare an aqueous solution of the hydrazide group-containing polymer (B). After preparing an aqueous solution of the hydrazide group-containing polymer (B), about 10 ml of 3N aqueous sodium hydroxide solution (3N-NaOH) is added and stirred for 1 hour. After stirring for 1 hour, 50 ml of 1/10 normal iodine solution (1/10 N-iodine solution) is added using a whole pipette and stirred for 4 hours. After stirring for 4 hours, about 15 ml of 3N aqueous hydrochloric acid (3N-HCl) is added and stirred for 10 minutes. After stirring for 10 minutes, starch is added as an indicator, and titration is performed with a 1/10 normal sodium thiosulfate solution (the end point is when the liquid becomes colorless and transparent), 1/10 normal sodium thiosulfate. The titration amount of the liquid is measured, and the titration amount (W ₁ ) of 1/10 normal sodium thiosulfate solution for the aqueous solution of the hydrazide group-containing polymer (B) is determined.

Further, the same operation as described above was carried out without using the hydrazide group-containing polymer (B), and the titration amount of 1/10 normal sodium thiosulfate solution was measured to contain the hydrazide group-containing polymer (B). Determine the titration (W ₀ ) of 1/10 normal sodium thiosulfate solution for no deionized water (blank state).

  Then, the hydrazide conversion rate (mol%) of the hydrazide group-containing polymer (B) is calculated according to the following calculation formula (1).

Hydrazide conversion rate (mol%) = [m _h / (m _h + m _a )] × 100 (1)
[In the calculation formula (1), m _h is the number of moles of the monomer unit having a hydrazide group, and is determined by the following calculation formula (1a). M _a is the number of moles of the monomer unit having an unsubstituted or mono-substituted carbamoyl group, and is determined by the following calculation formula (1b)]
m _h = 0.000025 × (W ₀ −W ₁ ) (1a)
[In the calculation formula (1a), W ₁ is a titration amount of a 1/10 normal sodium thiosulfate solution for an aqueous solution of the hydrazide group-containing polymer (B), and W ₀ is a 1/10 normal thiol for a blank state. This is a titration of sodium sulfate solution]
m _a = [W− (M _h × m _h )] / M _a (1b)
[In the calculation formula (1b), W is the mass of the hydrazide group-containing polymer (B). M _h is the molecular weight of the monomer units having a hydrazide group, M _a is the molecular weight of the monomer units having an unsubstituted or monosubstituted carbamoyl group. m _h is the same as above]

  The hydrazide group-containing polymer (B) has at least one unsubstituted or monosubstituted carbamoyl group and / or hydrocarbon-oxy-carbonyl group in the side chain in the molecule, and has a hydrazide group in the side chain in the molecule. If it has one or more, it may have one or two or more other groups in the molecule (especially in the side chain in the molecule). Such other groups are not particularly limited, and examples thereof include a carboxyl group, a group having an ester bond (alkoxycarbonyl group, aryloxycarbonyl group, cycloalkyloxycarbonyl group, etc.), a disubstituted carbamoyl group, a hydrocarbon group. (Alkyl group, aryl group, cycloalkyl group, etc.), alkyl-carbonyl-oxy group, halogen atom, alkoxy group, cyano group, hydroxy-alkyl-oxy-carbonyl group, epoxy-alkyl-oxy-carbonyl group, amino-alkyl -Oxy-carbonyl group, alkoxy-alkyl-oxy-carbonyl group and the like.

  Since the hydrazide group-containing polymer (B) is a polymer, the number of repeating units (structural units or monomer units) in the main chain is 2 or more. The number of repeating units of the main chain in the hydrazide group-containing polymer (B) is not particularly limited as long as it is 2 or more, and can be appropriately selected according to the target closed deposition time and pressing time. Specifically, the number of repeating units of the main chain in the hydrazide group-containing polymer (B) can be selected, for example, from a range corresponding to the following weight average molecular weight (for example, 100 to 1500).

  In the present invention, the weight average molecular weight of the hydrazide group-containing polymer (B) may be less than 10,000, but is preferably selected from a range of 10,000 or more. In addition, the upper limit of the weight average molecular weight of the hydrazide group-containing polymer (B) is not particularly limited, and can be appropriately selected according to the target closed deposition time, pressing time, and the like, for example, 150,000 or less. May be. Specifically, the weight average molecular weight of the hydrazide group-containing polymer (B) can be selected, for example, from the range of 10,000 to 150,000 (preferably 12,000 to 100,000, more preferably 15,000 to 50,000).

In addition, the weight average molecular weight of a hydrazide group containing polymer (B) can be calculated | required by a gel permeation chromatograph. Specifically, the weight average molecular weight of the hydrazide group-containing polymer (B) can be determined by measuring under the following measurement conditions using an apparatus trade name “HLC-8220GPC” (manufactured by Tosoh Corporation).
Measurement conditions Column: TSK-GEL ALPHA-2500, TSK-GEL ALPHA-4000, TSK-GEL ALPHA-6000
Column temperature: 40 ° C
Eluent: 10Mm LiBr aqueous solution Flow rate: 1ml / min
Standard: Poly (ethylene oxide); molecular weight 150, 620, 1470, 2.4 × 10 ⁴ , 5.0 × 10 ⁴ , 1.07 × 10 ⁵ , 1.4 × 10 ⁵ , 2.5 × 10 ⁵ , 5.4 × 10 ⁵

In the present invention, the hydrazide group-containing polymer (B) is a polymer (copolymer) of a monomer component having an ethylenically unsaturated bond (sometimes referred to as “ethylenically unsaturated monomer”) as the skeleton or main chain. It preferably has a skeleton or main chain formed by polymerization). As such a skeleton or main chain, for example, as a repeating unit (constituent unit or monomer unit), “—CH ₂ —CR ¹ X—” (R ¹ is a hydrogen atom or a methyl group, and X is unsubstituted or A group containing a mono-substituted carbamoyl group or a group containing a hydrocarbon-oxy-carbonyl group) and “—CH ₂ —CR ¹ Y—” (Y is a group containing a hydrazide group. R ¹ Is the same as the above) or a skeleton or main chain having at least. In the formula “—CH ₂ —CR ¹ X—”, the group containing an unsubstituted or monosubstituted carbamoyl group as X is not particularly limited as long as it is a group containing an unsubstituted or monosubstituted carbamoyl group. For example, it may be an unsubstituted or monosubstituted carbamoyl-organic group such as an unsubstituted or monosubstituted carbamoyl-alkyl group, but an unsubstituted or monosubstituted carbamoyl group is preferred. That is, the unsubstituted or monosubstituted carbamoyl group may be bonded to the carbon atom of the skeleton or the main chain via a divalent organic group, but is preferably bonded directly.

  Further, the group containing a hydrocarbon-oxy-carbonyl group as X is not particularly limited as long as it is a group containing a hydrocarbon-oxy-carbonyl group, and examples thereof include hydrocarbon-oxy-carbonyl-alkyl. A hydrocarbon-oxy-carbonyl-organic group such as a group may be used, but a hydrocarbon-oxy-carbonyl group is preferred. That is, the hydrocarbon-oxy-carbonyl group may be bonded to the carbon atom of the skeleton or main chain via a divalent organic group, but is preferably bonded directly.

Further, in the formula “—CH ₂ —CR ¹ Y—”, the group containing a hydrazide group as Y is not particularly limited as long as it is a group containing a hydrazide group, such as a hydrazide-alkyl group. Although it may be a hydrazide-organic group, a hydrazide group is preferred. That is, the hydrazide group may be bonded to the carbon atom of the skeleton or main chain via a divalent organic group, but is preferably bonded directly.

Therefore, as the hydrazide group-containing polymer (B), as a repeating unit, “—CH ₂ —CR ¹ (CONHR) —” (R and R ¹ are the same as above) by unsubstituted or mono-substituted (meth) acrylamide, and / or (meth) according acrylate "-CH ₂ -CR ¹ (COOR') -" and (R', R ¹ have the same meanings as defined above), (meth) "-CH ₂ -CR by acrylic acid hydrazide ¹ A (meth) acrylic acid hydrazide copolymer having at least (CONHNH ₂ ) — ”(R ¹ is the same as above) is preferable. The (meth) acrylic hydrazide copolymer includes, for example, (meth) acrylic hydrazide- (meth) acrylamide copolymer, (meth) acrylic hydrazide- (meth) acrylic ester copolymer And a (meth) acrylic acid hydrazide- (meth) acrylamide- (meth) acrylic acid ester copolymer. Such (meth) acrylic acid hydrazide-based copolymers can be copolymerized with (meth) acrylic acid hydrazide, unsubstituted or mono-substituted (meth) acrylamide or (meth) acrylic acid ester as a repeating unit. You may have the repeating unit by a monomer component. Examples of such a repeating unit include “—CH ₂ —CR ¹ R ² —” (R ¹ is the same as described above. R ² is a hydrazide group, an unsubstituted or mono-substituted carbamoyl group, and a hydrocarbon-oxy-carbonyl group. Other groups). Examples of the R ² group include a carboxyl group, a phenyl group, an alkyl-carbonyl-oxy group, a halogen atom, an alkoxy group, a cyano group, a hydroxy-alkyl-oxy-carbonyl group, and an epoxy-alkyl-oxy-carbonyl group. Amino-alkyl-oxy-carbonyl group, hydrogen atom, alkyl group, alkylene group, alkoxy-alkyl-oxy-carbonyl group, heterocyclic ring, N, N-dialkyl-amino-alkyl-oxy-carbonyl group and the like. The alkyl group in the alkyl group moiety (for example, the alkyl group moiety in the alkyl-carbonyl-oxy group) in the various groups of R ² is not particularly limited, and may be, for example, an alkyl group having 1 to 20 carbon atoms. It can be selected appropriately.

  The (meth) acrylic acid hydrazide-based copolymer may be any type of copolymer such as a random copolymer, an alternating copolymer, and a block copolymer, but is a random copolymer. It is preferable.

  In the present invention, acrylic hydrazide and methacrylic hydrazide are collectively referred to as (meth) acrylic hydrazide. Further, acrylamide and methacrylamide are collectively referred to as (meth) acrylamide, and acrylic acid ester and methacrylic acid ester are collectively referred to as (meth) acrylic acid ester. Other compounds are also generically named in the same manner.

  Examples of such a (meth) acrylic acid hydrazide copolymer include a (meth) acrylamide polymer and / or a (meth) acrylic acid ester polymer (B1-a) and hydrazine (B1-b). Examples thereof include (meth) acrylic acid hydrazide polymer (B1) which is a reaction product. The (meth) acrylic acid hydrazide polymer (B1) obtained by reacting the (meth) acrylamide polymer with hydrazine (B1-b) has an unsubstituted or mono-substituted carbamoyl group in the (meth) acrylamide polymer. , An amino-modified poly (meth) acrylamide polymer that has been partially converted into a hydrazide group (carbazoyl group) by reaction with hydrazine (B1-b). The (meth) acrylic acid hydrazide polymer (B1) obtained by the reaction of the (meth) acrylic acid ester polymer with hydrazine (B1-b) is a hydrocarbon-oxy group in the (meth) acrylic acid ester polymer. -A hydrazide-modified poly (meth) acrylic acid ester polymer in which a carbonyl group is partially converted to a hydrazide group (carbazoyl group) by reaction with hydrazine (B1-b). Furthermore, (meth) acrylic acid hydrazide polymer (B1) obtained by reaction of (meth) acrylamide polymer and (meth) acrylic acid ester polymer with hydrazine (B1-b) is (meth) acrylamide polymer The hydrocarbon-oxy-carbonyl group in the unsubstituted or mono-substituted carbamoyl group and / or the (meth) acrylic acid ester-based polymer is partially reacted with hydrazine (B1-b) to form a hydrazide group (carbazoyl group). (Meth) acrylic acid hydrazide-based polymer converted to (hydrazide).

  The (meth) acrylamide polymer for obtaining the (meth) acrylic acid hydrazide polymer (B1) is not particularly limited as long as it is a polymer having at least an unsubstituted or monosubstituted (meth) acrylamide unit as a repeating unit. However, for example, in addition to (meth) acrylamide homopolymers (for example, polyacrylamide, polymethacrylamide, etc.) based solely on unsubstituted or monosubstituted (meth) acrylamide, unsubstituted or monosubstituted (meth) acrylamide, (Meth) acrylamide copolymer with monomer component capable of copolymerization with substituted or mono-substituted (meth) acrylamide [for example, acrylamide- (meth) acrylic acid ester copolymer, methacrylamide- (meth) acrylic acid ester Copolymer, etc.] Door can be.

  In (meth) acrylamide homopolymers and (meth) acrylamide copolymers, as the unsubstituted or monosubstituted (meth) acrylamide, the nitrogen atom in acrylamide and / or methacrylamide is in an unsubstituted or monosubstituted state. For example, (meth) acrylamide, N-methylol (meth) acrylamide, N-methylolpropane (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meta) ) Acrylamide, N-propyl (meth) acrylamide, N-butyl (meth) acrylamide and the like.

  As the (meth) acrylamide polymer, polyacrylamide and polymethacrylamide can be suitably used. The (meth) acrylamide polymers can be used alone or in combination of two or more.

  The (meth) acrylic acid ester polymer for obtaining the (meth) acrylic acid hydrazide polymer (B1) is a polymer having at least a (meth) acrylic acid ester unit as a repeating unit. Although not limited, for example, (meth) acrylate homopolymers based only on (meth) acrylate (eg, polymethyl acrylate, polyethyl acrylate, polypropyl acrylate, polyisopropyl acrylate, polyacrylic acid n -Polyalkyl methacrylates such as butyl, polymethyl methacrylate, polyethyl methacrylate, polypropyl methacrylate, polyisopropyl methacrylate, polyalkyl methacrylates such as poly (n-butyl methacrylate), etc. Acrylic ester and the (meth ) (Meth) acrylate copolymer based on monomer component capable of copolymerization with acrylate ester [for example, (meth) acrylate copolymer using two or more kinds of (meth) acrylate ester, etc. ] Can be used.

In addition, in the (meth) acrylic acid ester homopolymer and (meth) acrylic acid ester copolymer, the (meth) acrylic acid ester is not particularly limited. For example, (meth) acrylic acid alkyl ester, (meth) acrylic Acid aryl ester, (meth) acrylic acid cycloalkyl ester and the like. Examples of the (meth) acrylic acid alkyl ester include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, (meth) Isobutyl acrylate, s-butyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, (Meth) acrylic acid 2-ethylhexyl, (meth) acrylic acid isooctyl, (meth) acrylic acid nonyl, (meth) acrylic acid isononyl, (meth) acrylic acid decyl, (meth) acrylic acid isodecyl, (meth) acrylic acid undecyl , Dodecyl (meth) acrylate, tridecyl (meth) acrylate, (me ) Tetradecyl acrylate, pentadecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, nonadecyl (meth) acrylate, eicosyl (meth) acrylate (meta) ) Acrylic acid C _1-20 alkyl ester and the like. Examples of the (meth) acrylic acid aryl ester include phenyl (meth) acrylate. Examples of (meth) acrylic acid cycloalkyl esters include cyclohexyl (meth) acrylate.

  As the (meth) acrylic acid ester polymer, a lower alkyl ester of polyacrylic acid such as polymethyl acrylate, polyethyl acrylate, polymethyl methacrylate, polyethyl methacrylate and the like can be suitably used. The (meth) acrylic acid ester polymer can be used alone or in combination of two or more.

  In addition, in the (meth) acrylamide copolymer and (meth) acrylic acid ester copolymer, as a monomer component that can be copolymerized with an unsubstituted or mono-substituted (meth) acrylamide or (meth) acrylic acid ester, for example, Carboxyl group-containing vinyl monomers, styrene monomers, vinyl esters, vinyl halides, vinyl ethers, cyano group-containing vinyl monomers, hydroxyl group-containing vinyl monomers, epoxy group-containing vinyl monomers, amino Examples thereof include group-containing vinyl monomers, olefins and dienes, alkoxy group-containing vinyl monomers, heterocyclic ring-containing vinyl monomers, and disubstituted (meth) acrylamides. Such monomer components may be used alone or in combination of two or more.

  In monomer components that can be copolymerized with unsubstituted or mono-substituted (meth) acrylamide or (meth) acrylic acid ester, carboxyl group-containing vinyl monomers, styrene monomers, vinyl esters, vinyl halides, Vinyl ethers, cyano group-containing vinyl monomers, hydroxyl group-containing vinyl monomers, epoxy group-containing vinyl monomers, amino group-containing vinyl monomers, olefins and dienes, alkoxy group-containing vinyl monomers, complex The ring-containing vinyl monomer can be appropriately selected from those exemplified in the section of the acetoacetyl group-containing polymer compound (A1). Examples of the di-substituted (meth) acrylamide include N, N-dimethyl (meth) acrylamide and N, N-diethyl (meth) acrylamide.

  On the other hand, the hydrazine (B1-b) may be hydrazine hydrate (hydrazine monohydrate, etc.) or anhydrous hydrazine. Hydrazine (B1-b) may be used alone or in combination of two or more. As hydrazine (B1-b), hydrazine hydrate (particularly hydrazine monohydrate) can be preferably used.

  In addition, the hydrazide conversion rate (mol%) of the (meth) acrylic acid hydrazide polymer (B1) is the same as that of the (meth) acrylamide polymer and / or the (meth) acrylic acid ester polymer (B1-a). It can be controlled by appropriately adjusting the ratio of the number of moles of hydrazine (B1-b) to the number of moles of the substituted carbamoyl group and / or hydrocarbon-oxy-carbonyl group. In addition, the weight average molecular weight of the (meth) acrylic acid hydrazide polymer (B1) should be adjusted as appropriate to the weight average molecular weight of the (meth) acrylamide polymer and / or (meth) acrylic acid ester polymer (B1-a). Can be controlled.

（式（１）中、Ｚは「−ＮＨＲ」（Ｒは水素原子又は炭化水素基である）または「−ＯＲ´」（Ｒ´は炭化水素基である）である。Ｒ¹は水素原子またはメチル基である。Ａは、（メタ）アクリル酸ヒドラジド、（メタ）アクリルアミドまたは（メタ）アクリル酸エステルと共重合が可能なモノマー成分による繰り返し単位である。ｎは１以上の整数である。ｍは１以上の整数である。ｐは０又は１以上の整数である） Such a (meth) acrylic acid hydrazide polymer (B1) can be represented by the following formula (1), for example.

(In the formula (1), Z is “—NHR” (R is a hydrogen atom or a hydrocarbon group) or “—OR ′” (R ′ is a hydrocarbon group), and R ¹ is a hydrogen atom or A is a methyl group, A is a repeating unit of a monomer component capable of copolymerization with (meth) acrylic acid hydrazide, (meth) acrylamide or (meth) acrylic acid ester, and n is an integer of 1 or more. Is an integer greater than or equal to 1. p is an integer greater than or equal to 1)

  The (meth) acrylic acid hydrazide polymer represented by the formula (1) is expressed as a block copolymer for convenience, but a random copolymer, an alternating copolymer, a block copolymer. It may have any form.

Z in Formula (1) may be either one or both of “—NHR” and “—OR ′”. That it is, represented by (meth) hydrazide polymer acrylic acid by the formula (1) is ^{_{"- CH 2 -CR 1 (CONHR)}} - " repeating unit represented by, and "-CH ₂ -CR ¹ (COOR It has at least one repeating unit among the repeating units represented by ')-'. The hydrocarbon group as R or R ′ is the same as described above. Specifically, examples of the hydrocarbon group according to R and R ′ include an alkyl group, an aryl group, and a cycloalkyl group, and an alkyl group (particularly, a lower alkyl group) is preferable. As R, a hydrogen atom, a lower alkyl group (methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, pentyl group, hexyl group, etc.) preferable. R is particularly preferably a hydrogen atom.

R ¹ in Formula (1) is a hydrogen atom or a methyl group, and a hydrogen atom is preferable.

Furthermore, A in the formula (1) is a unit of a monomer component capable of copolymerization with (meth) acrylic acid hydrazide, unsubstituted or monosubstituted (meth) acrylamide or (meth) acrylic acid ester, and the monomer component Is not particularly limited as long as it can be copolymerized with (meth) acrylic acid hydrazide, unsubstituted or monosubstituted (meth) acrylamide or (meth) acrylic acid ester. For example, as described above, a carboxyl group Containing vinyl monomer, styrene monomer, vinyl ester, vinyl halide, vinyl ether, cyano group-containing vinyl monomer, hydroxyl group-containing vinyl monomer, epoxy group-containing vinyl monomer, amino group-containing Vinyl monomers, olefins and dienes, alkoxy group-containing vinyl monomers, heterocyclic ring-containing vinyl monomers And di-substituted (meth) acrylamide. Specific examples of these monomer components are the same as described above. Therefore, A in Formula (1) may be “—CH ₂ —CR ¹ R ² —” (R ¹ and R ² are the same as above).

Furthermore, n, m, and p in Formula (1) are the numbers of each repeating unit, and n and m are integers of 1 or more, and p is 0 or an integer of 1 or more. Have the relationship.
0 <n / (n + m + p) <1
0 <m / (n + m + p) <1
0 ≦ p / (n + m + p) <1

  As the liquid (B), an aqueous solution containing the hydrazide group-containing polymer (B) or an aqueous dispersion (such as an aqueous emulsion) containing the hydrazide group-containing polymer (B) is suitable, and in particular, the hydrazide group-containing polymer (B). An aqueous solution containing can be preferably used.

  When an aqueous solution or aqueous dispersion (such as an aqueous emulsion) containing the hydrazide group-containing polymer (B) is used as the liquid (B), the hydrazide group-containing polymer (B) in the liquid (B) (aqueous solution or aqueous dispersion) Although it does not restrict | limit especially as a density | concentration (solid content density | concentration), For example, it can select from the range of 5 mass% or more (5-40 mass%, Preferably it is 10-30 mass%). When the concentration of the hydrazide group-containing polymer (B) is less than 5% by mass based on the total amount of the liquid (B), the hydrazide group-containing polymer (B) and the acetoacetyl group-containing polymer compound (A) in the liquid ( Reactivity with A1) decreases.

  In the present invention, in the hydrazide group-containing polymer (B) as the liquid (B), acid, alkali, surfactant (cationic surfactant, anionic surfactant, amphoteric surfactant, etc.), etc. Emulsifiers, resin emulsions (such as the resin emulsions exemplified above), fillers (kaolin, talc, clay, calcium carbonate, etc.), plasticizers, colorants, preservatives, rust inhibitors, fungicides, viscosity It may contain known additives such as regulators, wetting accelerators, viscosity improvers, and fragrances, and also includes aqueous organic solvents (eg, alcohols such as methanol and ethanol, glycol ethers, etc.) It may be.

  (B) As the aqueous solution or aqueous dispersion containing the hydrazide group-containing polymer (B) or the hydrazide group-containing polymer (B) as the liquid, the preparation method of the hydrazide group-containing polymer (B), the aqueous solution or the aqueous dispersion It can select suitably according to containing forms, such as a liquid. For example, an aqueous solution containing a hydrazide group-containing polymer (B) is obtained by mixing (meth) acrylamide polymer and / or (meth) acrylate polymer (B1-a) and hydrazine (B1-b) in an aqueous solvent. The reaction product containing the (meth) acrylic acid hydrazide polymer (B1) obtained by reacting can be used as it is without purification, but the (meth) acrylic acid hydrazide polymer ( B1) is precipitated and separated by a known method to obtain (meth) acrylic acid hydrazide polymer (B1), and this (meth) acrylic acid hydrazide polymer (B1) is dissolved or dispersed in water. Can be prepared.

  Specifically, using polyacrylamide as the (meth) acrylamide polymer and / or (meth) acrylic acid ester polymer (B1-a), using hydrazine monohydrate as the hydrazine (B1-b), When preparing an aqueous solution containing an acrylic acid hydrazide-acrylamide copolymer (aminopolyacrylamide) as the (meth) acrylic acid hydrazide polymer (B1), for example, an aqueous solution was prepared by mixing polyacrylamide and water. Thereafter, 100% hydrazine monohydrate is added to the aqueous solution, and the mixture is stirred at a predetermined temperature (for example, 40 to 95 ° C.) for a predetermined time (for example, 1 hour or more), thereby (meth) acrylic. After obtaining a reaction product containing an acrylic acid hydrazide-acrylamide copolymer as the acid hydrazide polymer (B1), the reaction The composition is introduced into a poor solvent of an acrylic hydrazide-acrylamide copolymer (alcohol solvent such as methanol) to precipitate an acrylic hydrazide-acrylamide copolymer, which is precipitated by filtration or the like. The acrylic hydrazide-acrylamide copolymer is isolated by separating the product, and then the acrylic hydrazide-acrylamide copolymer is dissolved in water at a predetermined ratio, thereby obtaining a predetermined concentration of acrylic hydrazide-acrylamide. An aqueous solution containing the copolymer can be prepared.

  As such a (meth) acrylic acid hydrazide polymer (B1), for example, as an amino-modified poly (meth) acrylamide polymer obtained by a reaction between a (meth) acrylamide polymer and hydrazine (B1-b), Otsuka A trade name “APA-P250”, a trade name “APA-P280”, a trade name “APA-M950”, a trade name “APA-M980”, and the like are commercially available from Chemical Co., Ltd.

[Two-component curable aqueous adhesive]
As described above, in the two-part curable aqueous adhesive of the present invention, an aqueous solution or an aqueous emulsion (A) containing an acetoacetyl group-containing polymer compound (A1) is used as the first liquid [(A) liquid]. And a two-component curable aqueous adhesive in which the hydrazide group-containing polymer (B) is used as the second solution [(B) solution]. Thus, since the hydrazide group-containing polymer (B) as a polymer is used as the active component of the liquid (B) (that is, the hydrazide group is introduced into the side chain of the polymer), the primer When the hydrazide group-containing polymer (B) as a component comes into contact with the acetoacetyl group-containing polymer compound (A1) in the liquid (A) as the main component, the low molecular weight hydrazide compound is used as a primer component. In comparison, the gelation reaction rate is greatly reduced and the curing rate is slow. That is, the two-component curable aqueous adhesive of the present invention is not a fast curable type. Therefore, when the wood material is bonded using the two-component curable aqueous adhesive of the present invention, the closed deposition time is set to a sufficient time for operation [for example, 30 seconds or more (30 seconds to 5 minutes), preferably Can be secured in 45 seconds to 3 minutes, more preferably 50 seconds to 2 minutes]. Moreover, since the two-part curable aqueous adhesive of the present invention has a plurality of crosslinking points in the same polymer main chain, it has a high crosslinking density and has excellent adhesive properties even in a short pressing time. And water resistance can be exhibited.

  Of course, since the reaction mechanism of the reaction (crosslinking reaction) between the liquid (A) and the liquid (B) is a mechanism that cures by a chemical reaction, the two-liquid curable aqueous adhesive includes the liquids (A) and (B). Can cause the crosslinking reaction to proceed with little influence of air temperature and material temperature, and hardly cause the influence of air temperature and material temperature when bonding.

  In particular, by using an aqueous solution or emulsion containing the acetoacetyl group-containing polymer compound (A1) and the isocyanate compound (A2) as the liquid (A) (specifically, the acetoacetyl group-containing polymer) Even if the pressing time is short [for example, 10 minutes, by using an aqueous solution or aqueous emulsion in a form in which the isocyanate compound (A2) is mixed in an aqueous solution or emulsion containing the molecular compound (A1)] The following (preferably 5 minutes or less, more preferably 2 to 4 minutes, especially about 3 minutes), conforms to JAS structural laminated wood standards that require high water resistance, and increases productivity Can be improved.

  Moreover, since the two-part curable aqueous adhesive of the present invention is aqueous, it is excellent in handling and workability and is also environmentally friendly. In particular, since a component having low toxicity is used as the liquid (B), safety to the human body is high.

  Examples of adherends that can be bonded with the two-part curable aqueous adhesive of the present invention include wood materials such as wood, plywood, chipboard, particle board, and hard board; slate boards, quartz boards, mortar, tiles. Inorganic materials such as melamine resin decorative plates, bakelite plates, polystyrene materials such as foamed polystyrene; paper-based materials such as corrugated paper, paperboard and kraft paper. Therefore, for example, in the wood industry such as bonding of wooden materials in flash panels, decorative plywood, prefabricated panels, laminated lumber, etc. and assembling of wooden materials using edges, hozo, dowel, tome, hagi, square wood, etc. It can be used for paper processing such as adhesion of wood materials, corrugated cardboard, slip paper, paper tube, and paper bag making.

  Since the two-part curable aqueous adhesive of the present invention is a two-part curable aqueous adhesive using a combination of the (A) liquid and the (B) liquid, the (A) liquid and the (B) liquid Two liquids may be mixed and used, but it is preferable to separately apply the liquid (A) and the liquid (B). That is, it is preferable to apply the liquid (A) and the liquid (B) to the respective predetermined surfaces (bonded surfaces) of the two adherends to be bonded (so-called separate application). Thus, the two-component curable aqueous adhesive of the present invention is not used by mixing the (A) solution and the (B) solution at the time of use, but separately using the (A) solution and the (B) solution. It can be suitably used as a two-component fractional application type water-based adhesive (so-called “honeymoon type water-based adhesive”) that is used by applying to the surface.

  In addition, when using a two-component curable aqueous adhesive in the form of fractional application, either one of the liquid (A) and the liquid (B) is applied to one of the two surfaces to be bonded. After that, the other liquid can be applied on the coated surface (so-called overcoating) and used. In this overcoating, after applying (B) liquid and drying, the method of apply | coating (A) liquid on the surface of this (B) liquid can be employ | adopted suitably.

  Of course, after the two-component curable aqueous adhesive is applied, the adherend surfaces can be bonded to each other by pressing both adherend surfaces together.

  As described above, the two-component curable aqueous adhesive of the present invention is hardly affected by the temperature and the material temperature, and can secure a sufficient closed deposition time for work when adhering the wood material. At the same time, an excellent adhesive force can be exerted even in a short pressing time. Therefore, when the two-component curable aqueous adhesive is used, a plurality of wooden materials are laminated and adhered. Laminates (for example, flash panels, decorative plywood, prefabricated panels, laminated wood, etc.) can be produced with excellent productivity.

[Adhesion method]
In the method for adhering an adherend using the two-component curable aqueous adhesive of the present invention, the two-component curable aqueous adhesive, that is, the first solution [(A) solution] is used as the two-component curable aqueous adhesive. A two-component curable type in which an aqueous solution or an aqueous emulsion (A) containing an acetyl group-containing polymer compound (A1) is used, and a hydrazide group-containing polymer (B) is used as the second solution [(B) solution]. By using a water-based adhesive and adjusting the reactivity of the acetoacetyl group-containing polymer (A1) and the hydrazide group-containing polymer (B), the closed deposition time and pressing time are controlled, The dressing is adhered. The reactivity between the acetoacetyl group-containing polymer (A1) and the hydrazide group-containing polymer (B) is not limited to the weight average molecular weight and molecular chain length of the hydrazide group-containing polymer (B). It can be controlled by the number of hydrazide groups contained in the molecule of the polymer (B), the ratio of the hydrazide group-containing polymer (B) to the acetoacetyl group-containing polymer compound (A1), and the like.

  When applying the two-component curable aqueous adhesive to the adherend, as described above, (i) a predetermined surface (cover) of each of the two adherends to be bonded by the fractional application method. The liquid (A) and the liquid (B) may be separately applied to the adhesive surface), and (ii) either the liquid (A) or the liquid (B) by the overcoating method. After coating, the other liquid may be coated on the coated surface.

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited by these Examples. In the following, “part” means “part by mass” and “%” means “% by mass” unless otherwise specified.

Example 1
The following (A) liquid and the following (B) liquid were used as each component of the two-component curable aqueous adhesive.

-(A) Liquid: 400 parts of water was put into a reaction vessel equipped with a stirrer, reflux condenser, dropping tank and thermometer, and the product name "Gosefimer Z200" (made by Nippon Synthetic Chemical Industry Co., Ltd. Acetyl-modified polyvinyl alcohol): 100 parts were added and kept at 80 ° C. After the acetoacetyl-modified polyvinyl alcohol is completely dissolved, the liquid temperature is cooled to 50 ° C., and then the product name “DL-612” (Asahi Kasei Kogyo Co., Ltd., styrene-butadiene copolymer emulsion) is added and stirred. After mixing, the mixture was cooled to room temperature to prepare a main agent (base).

  Based on 100 parts by mass of the main agent: Trade name “Sumidur 44V20” (manufactured by Sumika Bayer Urethane Co., Ltd .; 4,4′-diphenylmethane diisocyanate) is added at a ratio of 15 parts by mass, and the mixture is sufficiently stirred. One liquid [Liquid (A)] was obtained.

-(B) liquid A brand name "APA-P250" (The Otsuka Chemical Co., Ltd. make, aminopolyacrylamide, a weight average molecular weight: 23000, hydrazide conversion rate: 48 mol%) is dissolved in water, and a density | concentration is 20 mass%. A second solution [Liquid (B)] was obtained.

(Example 2)
The following (A) liquid and the following (B) liquid were used as each component of the two-component curable aqueous adhesive.

-(A) Liquid: 400 parts of water was put into a reaction vessel equipped with a stirrer, reflux condenser, dropping tank and thermometer, and the product name "Gosefimer Z200" (made by Nippon Synthetic Chemical Industry Co., Ltd. Acetyl-modified polyvinyl alcohol): 50 parts were added and kept at 80 ° C. After the acetoacetyl-modified polyvinyl alcohol is completely dissolved, the liquid temperature is cooled to 50 ° C., and then the product name “DL-612” (manufactured by Asahi Kasei Kogyo Co., Ltd., styrene-butadiene copolymer emulsion) is added and stirred. After mixing, the mixture was cooled to room temperature to prepare a main agent (base).

  Based on 100 parts by mass of the main agent: Trade name “Sumidur 44V20” (manufactured by Sumika Bayer Urethane Co., Ltd .; 4,4′-diphenylmethane diisocyanate) is added at a ratio of 15 parts by mass, and the mixture is sufficiently stirred. One liquid [Liquid (A)] was obtained.

-(B) liquid The 2nd liquid [(B) liquid] obtained by carrying out similarly to Example 1 was used.

(Example 3)
The following (A) liquid and the following (B) liquid were used as each component of the two-component curable aqueous adhesive.

-(A) Liquid: 400 parts of water was put into a reaction vessel equipped with a stirrer, reflux condenser, dropping tank and thermometer, and the product name "Gosefimer Z200" (made by Nippon Synthetic Chemical Industry Co., Ltd. Acetyl-modified polyvinyl alcohol): 100 parts were added and kept at 80 ° C. After the acetoacetyl-modified polyvinyl alcohol is completely dissolved, the liquid temperature is cooled to 50 ° C., then, trade name “OM28NT” (manufactured by Kuraray Co., Ltd .; ethylene-vinyl acetate copolymer emulsion): 500 parts is added and mixed by stirring. Then, the mixture was cooled to room temperature to prepare a main agent (base).

  Based on 100 parts by mass of the main agent: Trade name “Sumidur 44V20” (manufactured by Sumika Bayer Urethane Co., Ltd .; 4,4′-diphenylmethane diisocyanate) is added at a ratio of 15 parts by mass, and the mixture is sufficiently stirred. One liquid [Liquid (A)] was obtained.

-(B) liquid The 2nd liquid [(B) liquid] obtained by carrying out similarly to Example 1 was used.

Example 4
The following (A) liquid and the following (B) liquid were used as each component of the two-component curable aqueous adhesive.

-(A) liquid The 1st liquid [(A) liquid] obtained by carrying out similarly to Example 1 was used.

-(B) Liquid Aminopolyacrylamide (trade name “APA-P230” (Otsuka Chemical Co., Ltd.) having an acrylic hydrazide unit and an acrylic amide unit as a monomer unit and having a hydrazide conversion rate of 36 mol%. Manufactured, weight average molecular weight: 23000) was dissolved in water to prepare an aqueous solution having a concentration of 20% by mass to obtain a second liquid [liquid (B)].

(Example 5)
The following (A) liquid and the following (B) liquid were used as each component of the two-component curable aqueous adhesive.

-(A) liquid The main ingredient was produced like Example 1 and this main ingredient was used as the 1st liquid [(A) liquid]. Specifically, in a reaction vessel equipped with a stirrer, a reflux condenser, a dripping tank, and a thermometer, 400 parts of water was put, and the product name “Gosefeimer Z200” (produced by Nippon Synthetic Chemical Industry Co., Ltd. Acetyl-modified polyvinyl alcohol): 100 parts were added and kept at 80 ° C. After the acetoacetyl-modified polyvinyl alcohol is completely dissolved, the liquid temperature is cooled to 50 ° C., and then the product name “DL-612” (Asahi Kasei Kogyo Co., Ltd., styrene-butadiene copolymer emulsion) is added and stirred. Then, the mixture was cooled to room temperature to obtain the first liquid [liquid (A)].

  Therefore, the (A) liquid according to Example 5 does not contain a curing agent (crosslinking agent).

-(B) liquid The 2nd liquid [(B) liquid] obtained by carrying out similarly to Example 1 was used.

(Comparative Example 1)
The following (A) liquid and the following (B) liquid were used as each component of the two-component curable aqueous adhesive.

-(A) Liquid: 400 parts of water was put into a reaction vessel equipped with a stirrer, a reflux condenser, a dripping tank, and a thermometer. Part was added and kept at 80 ° C. After the polyvinyl alcohol is completely dissolved, the liquid temperature is cooled to 50 ° C., and then the trade name “DL-612” (manufactured by Asahi Kasei Kogyo Co., Ltd., styrene-butadiene copolymer emulsion) is added and mixed with stirring. Then, the mixture was cooled to room temperature to prepare a main agent (base).

  Based on 100 parts by mass of the main agent: Trade name “Sumidur 44V20” (manufactured by Sumika Bayer Urethane Co., Ltd .; 4,4′-diphenylmethane diisocyanate) is added at a ratio of 15 parts by mass, and the mixture is sufficiently stirred. One liquid [Liquid (A)] was obtained.

-(B) liquid The 2nd liquid [(B) liquid] obtained by carrying out similarly to Example 1 was used.

(Comparative Example 2)
The following liquid (A) was used as a component of the curable aqueous adhesive. That is, in the curable aqueous adhesive according to Comparative Example 2, the second liquid [(B) liquid] used as a primer is not used, and only the first liquid [(A) liquid] is used. .

-(A) liquid The 1st liquid [(A) liquid] obtained by carrying out similarly to Example 1 was used.

(Comparative Example 3)
The following (A) liquid and the following (B) liquid were used as each component of the two-component curable aqueous adhesive.

-(A) liquid The 1st liquid [(A) liquid] obtained by carrying out similarly to Example 1 was used.

-(B) liquid Adipic acid dihydrazide (trade name "adipic acid dihydrazide" manufactured by Otsuka Chemical Co., Ltd.) is dissolved in water to prepare an aqueous solution having a concentration of 8% by mass, and the second liquid [(B) liquid ] Was obtained.

(Comparative Example 4)
The following liquid (A) was used as a component of the curable aqueous adhesive. That is, in the curable aqueous adhesive according to Comparative Example 4, the second liquid [(B) liquid] used as a primer is not used, and only the first liquid [(A) liquid] is used. .

-(A) liquid The 1st liquid [(A) liquid] obtained by carrying out similarly to Example 5 was used.

  Therefore, the liquid (A) according to Comparative Example 4 does not contain a curing agent (crosslinking agent).

(Evaluation)
Each of the two-component curable aqueous adhesives according to Examples 1 to 4 and Comparative Examples 1 to 3 (in the case of Comparative Example 2, one-component curable aqueous adhesive) was tested by the following test sample preparation method (1). After preparing the sample, measure the normal bond strength and boiling repeated bond strength by the following normal bond strength measurement method, boiling repeated bond strength measurement method, boiling peel test method, and reduced pressure test method. At the same time, it was evaluated whether or not it conforms to the standard for structural laminated wood standardized by the Japan Agricultural Standards Association (JAS Association). The evaluation results are shown in Table 1.

  Moreover, about each two-component curable aqueous adhesive which concerns on Example 1 and Comparative Example 3, after producing a test sample by the following test sample preparation method (2), the following measuring method of normal adhesive strength, repeated boiling Measurement of adhesive strength, boiling peel test method, reduced pressure test method, normal adhesive strength, repeated boiling adhesive strength are measured, and structural assembly that is standardized by the Japan Agricultural Standards Association (JAS Association) It was evaluated whether or not it conforms to the standard for materials. The evaluation results are shown in Table 2.

  Further, for each of the two-part curable aqueous adhesives according to Example 1, Example 5 and Comparative Example 4 (in the case of Comparative Example 4, one-part curable aqueous adhesive), the following initial adhesive strength measurement method Was used to measure the initial bond strength. The measurement results are shown in Table 3.

(Test sample preparation method (1))
Both sides of white wood (length: 300mm, width: 100mm, thickness 30mm; 3ply) are smoothed with a planar to obtain two white woods that are smooth on both sides. The second liquid [(B) liquid] as a primer was applied at a coating amount of 20 g / m ² in one atmosphere of 23 ° C. and 50% RH {the second liquid according to Comparative Example 3 [( The coating amount of B) liquid] is 40 g / m ² } and dried at room temperature (20 to 25 ° C.). Thereafter, the first liquid [(A) liquid] is applied to one surface of the other white wood in an atmosphere of 23 ° C. and 50% RH at an application amount: 200 g / m ² , and the closing deposition time becomes 1 minute. Two whitewoods are bonded together in such a manner that the application surface of the second liquid [(B) liquid] and the application surface of the first liquid [(A) liquid] are in contact with each other, and the bonding press machine Then, after pressing and releasing the pressure under the conditions of pressing pressure: 10 kg / cm ² and pressing time: 3 minutes, each test sample was cured at room temperature (20-25 ° C.) for 6 days. Three were produced.
In addition, since the 2nd liquid [(B) liquid] as a primer is not used for the curable aqueous adhesive which concerns on the comparative example 2, except not having apply | coated 2nd liquid [(B) liquid]. Three test samples were prepared in the same manner as described above.

(Test sample preparation method (2))
Both sides of white wood (length: 300mm, width: 100mm, thickness 30mm; 3ply) are smoothed with a planar to obtain two white woods that are smooth on both sides. The second liquid [(B) liquid] as a primer was applied at a coating amount of 20 g / m ² in one atmosphere of 23 ° C. and 50% RH {the second liquid according to Comparative Example 3 [( The coating amount of B) liquid] is 40 g / m ² } and dried at room temperature (20 to 25 ° C.). Thereafter, the first liquid [(A) liquid] is applied at a coating amount of 200 g / m ² on one surface of the other white wood in an atmosphere of 23 ° C. and 50% RH, and the closing deposition time becomes 0 minutes. Under the conditions (that is, immediately after applying the first liquid [(A)], two whitewoods are applied to the application surface of the second liquid [(B)] and the first liquid [(A). In the form in contact with the application surface of the liquid, after pressing and releasing with a bonding press machine under the conditions of pressing pressure: 10 kg / cm ² and pressing time: 3 minutes, Three test samples were prepared each for 6 days at room temperature (20 to 25 ° C.).

(Measurement method of normal bond strength)
About the test sample obtained by the test sample preparation method (1) or the test sample preparation method (2), the normal bond strength was measured according to JIS K 6806 (2003). In addition, the state of fracture in the adherend was examined, and the ratio of the fractured area to the shear area was determined as the material fracture rate (%). Specifically, after obtaining a test sample by the test sample preparation method (1) or the test sample preparation method (2), the test sample is cut into a size of length: 30 mm and width: 25 mm to prepare a test piece. After curing for 6 days at room temperature (20 to 25 ° C.), the compression shear bond strength (N / mm ² ) of the test sample was measured in an atmosphere of 23 ° C. and 50% RH.

(Measurement method of repeated boiling adhesive strength)
About the test sample obtained by the test sample preparation method (1) or the test sample preparation method (2), the boil repeated adhesive strength was measured according to JIS K 6806 (2003). In addition, the state of fracture in the adherend was examined, and the ratio of the fractured area to the shear area was determined as the material fracture rate (%). Specifically, after obtaining a test sample by the test sample preparation method (1) or the test sample preparation method (2), the test sample is cut into a size of length: 30 mm and width: 25 mm to prepare a test piece. After aging for 6 days at room temperature (20 to 25 ° C.), the test piece was immersed in boiling water for 4 hours, then dried in air at 60 ± 3 ° C. for 20 hours, and further immersed in boiling water for 4 hours. Then, the sample was immersed in water at room temperature until it cooled, and the compression shear bond strength (N / mm ² ) of the test sample was measured in an atmosphere of 23 ° C. and 50% RH while remaining wet.

(Boil peeling test method)
About the test sample obtained by the test sample preparation method (1) or the test sample preparation method (2), a boiling peeling test is performed on the structural laminated wood standardized by the Japan Agricultural Standards Association (JAS Association). It was evaluated whether or not it conforms to the standard for structural laminated wood standardized by the Agricultural and Forestry Standards Association (JAS Association). Specifically, after a test sample was cut into a length of 75 mm to prepare a test piece, the test piece was immersed in boiling water for 4 hours, and further immersed in water at room temperature (10 to 25 ° C.) for 1 hour. The test piece taken out from the water is put in a constant temperature dryer at 70 ± 3 ° C. and dried for 24 hours or more so that moisture does not accumulate in the vessel, and the moisture content after drying becomes less than the moisture content before the test. Like that.
Thereafter, the length of the peeling at the both ends of the test piece is measured, and the total of the peeling rate at both ends and the peeling length at the same adhesive layer is calculated.

The peeling rate is calculated by the following formula: “peeling rate (%) = (L _A / L _B ) × 100 (L _A is the sum of the lengths of peeling at both ends, and L _B is the length at both ends. It is the total length of the adhesive layer) ”. Also, when measuring the length of peeling, destruction of wood due to dry cracks, knots, etc. is not considered peeling.

  For the structural laminated wood standardized by the Japan Agricultural Standards Association (JAS Association), the case where it conforms to the standard related to the boiling peeling test standardized by the JAS Association is indicated as “O”, and the case where it does not conform “×” was evaluated.

  According to the Japan Agricultural Standards (JAS), the standard of structural laminated lumber is the result of the boiling peeling test as described above, the peel rate at the both ends of the test piece is 5% or less, and the same adhesion The total separation length in the layers is less than one quarter of each length.

(Pressure reduction test method)
About the test sample obtained by the test sample preparation method (1) or the test sample preparation method (2), a reduced pressure test is performed on the structural laminated material standardized by the Japan Agricultural Standards Association (JAS Association). It was evaluated whether or not it conforms to the standard for structural laminated wood standardized by the Japan Agricultural Standards Association (JAS Association). Specifically, after a test sample was cut into a length of 75 mm to prepare a test piece, the test piece was immersed in water at room temperature (10 to 25 ° C.), decompressed at 0.085 MPa for 5 minutes, and further A pressure of 0.51 ± 0.03 MPa is applied for 1 hour. After this treatment was repeated twice, the test piece was taken out of water and placed in a constant temperature dryer at 70 ± 3 ° C., and dried for at least 24 hours so as not to accumulate moisture in the vessel. Is less than the moisture content before the test.
Thereafter, the length of the peeling at the both ends of the test piece is measured, and the total of the peeling rate at both ends and the peeling length at the same adhesive layer is calculated.

The peeling rate is calculated by the following formula: “peeling rate (%) = (L _A / L _B ) × 100 (L _A is the sum of the lengths of peeling at both ends, and L _B is the length at both ends. It is the total length of the adhesive layer) ”. Also, when measuring the length of peeling, destruction of wood due to dry cracks, knots, etc. is not considered peeling.

  And, for structural laminated wood standardized by the Japan Agricultural Standards Association (JAS Association), the case where it conforms to the standard related to the decompression and pressurization test standardized by the JAS Association shall be “○”, and the case where it does not conform Evaluated as “x”.

  According to the Japan Agricultural Standards (JAS), the standard for structural laminated wood is the same as the result of the above-described decompression and pressure test, and the peel rate at both ends of the test piece is 5% or less and the same The total length of peeling in the adhesive layer is not more than a quarter of each length.

(Measurement method of initial bond strength)
A particle board (manufactured by Onahama Plywood Co., Ltd.) having a thickness of 10 mm was cut into a size of 8 cm × 8 cm to produce a particle board piece. In addition, a 3 mm thick MDF (manufactured by Nelson Pine Industries Limited) was cut into 8 cm × 9 cm to produce an MDF piece. Then, the MDF piece is adhered to one side of the particle board piece in advance so that the MDF piece protrudes about 1 cm on one side of the particle board piece (so-called “discarding”), A particle board piece to which the MDF piece was bonded was produced.

(B) The liquid was applied to the surface of an MDF piece (8 cm × 9 cm, thickness 3 mm) and dried. Then, (A) liquid is apply | coated to the surface by the side of the particle board in the particle board piece by which the MDF piece was adhere | attached on the single side | surface, and the application surface of B liquid of the MDF piece which apply | coated and dried (B) liquid on this application surface Were overlapped and pressed for 3 minutes at a pressing pressure of 5 kgf / cm ² , with the MDF protruding about 1 cm on the same side. After pressing, the pressure was released (uncompressed), the MDF piece was immediately peeled off, and the adhesive strength (N / 80 mm width) at that time was measured to obtain the initial adhesive strength.

  In addition, since the 2nd liquid [(B) liquid] as a primer is not used for the curable aqueous adhesive which concerns on the comparative example 4, except not having apply | coated 2nd liquid [(B) liquid]. In the same manner as described above, the adhesive strength (N / 80 mm width) was measured to determine the initial adhesive strength.

  From Table 1 and Table 2, the two-component curable aqueous adhesives according to Examples 1 to 4 have both good normal-state adhesive strength and boiling repeated adhesive strength defined by JIS. Furthermore, when the two-component curable aqueous adhesive according to Examples 1 to 4 is used, the boiling peeling test and the reduced pressure test, which are tests specified by JAS, are also severe regarding structural laminated materials specified by JAS. It is possible to produce structural laminated materials that meet the standards.

  Therefore, the two-part curable aqueous adhesive according to the embodiment can secure a sufficient working time (about 1 minute) as a closed deposition time when the wooden material is adhered, and a short pressing time ( Even about 3 minutes), an excellent adhesive force can be exhibited. That is, when the two-part curable aqueous adhesive according to the example is used, it is possible to produce a structural laminated material that conforms to the strict standards for structural laminated material specified by JAS, and has excellent productivity. It is possible to produce structural laminates.

  In addition, the standard regarding the structural laminated material standardized by JAS is that the length of the test piece is 75 mm, which is larger than the size when measuring the normal bond strength and boiling repeated bond strength according to JIS, and is a strict standard. ing.

  Further, from Table 3, it was confirmed that when the liquid (A) contains a curing agent (crosslinking agent), excellent initial adhesive strength can be exhibited. Of course, even if (A) liquid does not contain a hardening | curing agent, initial stage adhesive strength is excellent.

Claims (7)

A two-component curable aqueous adhesive comprising the following (A) solution and (B) solution.
(A) An aqueous solution or aqueous emulsion containing a polymer compound (A1) having an acetoacetyl group in the molecule (B) An unsubstituted or monosubstituted carbamoyl group and / or hydrocarbon-oxy-carbonyl on the side chain in the molecule And hydrazide group-containing polymer having a hydrazide group in the side chain in the molecule The two-component curable aqueous adhesive according to claim 1, wherein the hydrazide group-containing polymer (B) has a skeleton or a main chain formed by polymerization of a monomer component having an ethylenically unsaturated bond. The hydrazide group-containing polymer (B) is a reaction product of a (meth) acrylamide polymer and / or a (meth) acrylic acid ester polymer (B1-a) and a hydrazine (B1-b). The two-component curable aqueous adhesive according to claim 1 or 2, which is an acid hydrazide polymer (B1). The two-component curable aqueous adhesive according to any one of claims 1 to 3, wherein the polymer compound (A1) having an acetoacetyl group in the molecule is a modified polyvinyl alcohol having an acetoacetyl group in the molecule. The two-component curable aqueous solution according to any one of claims 1 to 4, wherein an isocyanate-based compound (A2) is further contained in the aqueous solution or aqueous emulsion (A) containing the polymer compound (A1). adhesive. The two-component curable aqueous adhesive according to any one of claims 1 to 5, which is a two-component fractional application type aqueous adhesive. A method for adhering an adherend using a two-component curable aqueous adhesive, wherein the two-component curable aqueous adhesive according to any one of claims 1 to 6 is used as the two-component curable aqueous adhesive. By applying an aqueous solution or emulsion (A) on the surface of one adherend and applying a hydrazide group-containing polymer (B) on the other adherend, A method for adhering an adherend with a two-component curable aqueous adhesive, characterized by adhering a dressing.