JP5183048B2 - Water-based adhesive and laminate using the same - Google Patents

Description

  The present invention relates to a water-based adhesive and a laminate using the same.

  Polyolefin resins, especially modified polyolefin resins, have good thermal adhesion to various materials, so they are used in a wide range of applications such as heat sealing agents, delayed tack agents, fiber treatment agents, and adhesive binders. Yes. Such a resin is used as an aqueous dispersion from the viewpoint of workability and environment.

  For example, an aqueous dispersion of an ethylene-unsaturated carboxylic acid copolymer resin such as an ethylene-acrylic acid copolymer resin or an ethylene-methacrylic acid copolymer resin having an unsaturated carboxylic acid content of about 20% by mass has been conventionally known. It has been. However, since such a resin has a high polarity, adhesion and heat sealability to a material with low polarity such as polyethylene terephthalate and polypropylene are insufficient.

  On the other hand, an aqueous dispersion of a polyolefin resin having a lower unsaturated carboxylic acid content is disclosed in Patent Document 1 and the like. However, such an aqueous dispersion is made aqueous by using an emulsifier (surfactant), a protective colloid or the like. Emulsifiers, protective colloids, and the like are substances that greatly affect the state of the adhesive interface, and the use of such an emulsifier or protective colloid is likely to reduce the adhesion and heat sealability. Moreover, since they are highly hydrophilic, there is a problem that the water resistance and boil resistance of the formed coating film are remarkably lowered. Furthermore, coating films containing an emulsifier, a protective colloid, and the like are not preferable in terms of environment and hygiene because they may bleed out, and the adhesiveness may change over time.

Therefore, the present inventors have proposed that the modified polyolefin resin is made into an aqueous dispersion without adding a non-volatile compound such as a surfactant (Patent Document 2). However, although these known techniques have adhesion and heat sealability to substrates such as polyethylene terephthalate and polypropylene, there is room for further improvement in the adhesion.
JP-A-9-296081 International Publication No. 02/055598 Pamphlet

  As described above, conventional aqueous adhesives have room for improvement in the water resistance, adhesiveness, heat sealability, and the like of the coating film. Then, an object of this invention is to obtain the water-based adhesive excellent in the water resistance of a coating film, adhesiveness with various base materials, adhesiveness, etc., and a laminated body using the same.

  As a result of intensive studies, the present inventors have found that an adhesive containing a polyolefin resin having a specific composition and another polyolefin resin is excellent in water resistance of the coating film and adhesion to various substrates, and each polyolefin resin alone As a result, the present inventors have found an unexpected effect of exhibiting much better adhesion than the case, and have reached the present invention.

That is, the gist of the present invention is as follows.
(1) An unsaturated carboxylic acid component (A1), an ethylene-based hydrocarbon component (A2), an acrylic ester component or a methacrylic ester (A3), and the mass of each component of (A1) to (A3) A polyolefin resin (A) having a ratio satisfying the following formulas (i) and (ii) , 0.1 to 7% by mass of an unsaturated carboxylic acid component (B1), and 25 of an acrylate ester component or a methacrylate ester (B3). An aqueous adhesive comprising: another polyolefin resin (B) contained in an amount of less than mass% ; a basic compound (C); and an aqueous medium.

0.01 ≦ (A1) / {(A1) + (A2) + (A3)} × 100 ≦ 7 (i)
28 ≦ (A3) / {(A1) + (A2) + (A3)} × 100 ≦ 35 (ii)

  (2) The aqueous adhesive according to (1), wherein the mass ratio (A) / (B) of the polyolefin resin (A) to the other polyolefin resin (B) is 1/99 to 60/40.

  (3) Further containing a crosslinking agent component, the amount of which is 0.1 to 50 parts by mass with respect to 100 parts by mass of the total amount of the polyolefin resin (A) and the other polyolefin resin (B). The water-based adhesive according to (1) or (2).

  (4) A base material on which a coating film is formed, wherein a coating film is formed by removing the aqueous medium from the aqueous adhesive of any one of (1) to (3) above on the surface of the base material.

  (5) The above-mentioned coating film of the substrate on which the coating film of (4) is formed is used as an adhesive layer, and an adherend is bonded to the above-mentioned substrate through this adhesive layer. Laminated body.

  According to the present invention, an adhesive containing a polyolefin resin having a specific composition and another polyolefin resin is excellent in water resistance of a coating film and adhesion to various substrates, and is far superior to the case of each polyolefin resin alone. Adhesiveness is expressed. Furthermore, the base material on which the coating film of the present invention is formed, the coating film does not substantially contain a non-volatile compound such as a surfactant. The adhesiveness is not adversely affected and the adhesiveness does not deteriorate over time. Furthermore, performance, such as the boil resistance of a coating film, can be improved by combining a crosslinking agent.

The present invention will be described in detail below.
The aqueous adhesive of the present invention includes an unsaturated carboxylic acid component (A1), an ethylene-based hydrocarbon component (A2), and an acrylic ester component or a methacrylic ester (A3), and (A1) to (A3) The polyolefin resin (A) satisfying the following formulas (i) and (ii), the other polyolefin resin (B), the basic compound (C), and an aqueous medium are contained. . The aqueous medium is a medium containing water as a main component, and may contain a water-soluble organic solvent described later.

0.01 ≦ (A1) / {(A1) + (A2) + (A3)} × 100 ≦ 7 (i)
28 ≦ (A3) / {(A1) + (A2) + (A3)} × 100 ≦ 35 (ii)

  In the polyolefin resin (A), the content of the unsaturated carboxylic acid component (A1) is in the range of the above formula (i), that is, 0. It is necessary that the content be not less than 01% by mass and not more than 7% by mass. When the content of the component (A1) is less than 0.01% by mass, it becomes difficult to make the resin aqueous (liquefied) without adding a non-volatile compound such as a surfactant. On the other hand, when the content rate of (A1) component exceeds 7 mass%, there exists a possibility that adhesiveness with a polyolefin base material and heat-sealability may fall. Therefore, the content of the component (A1) is more preferably 0.1% by mass or more and 5% by mass or less, further preferably 0.5% by mass or more and less than 5% by mass, most preferably 1% by mass or more, 4% It is below mass%.

  The unsaturated carboxylic acid component (A1) is introduced by an unsaturated carboxylic acid or its anhydride. Specifically, acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid In addition to crotonic acid, half esters and half amides of unsaturated dicarboxylic acids. Among these, acrylic acid, methacrylic acid, maleic acid, and maleic anhydride are preferable, and acrylic acid and maleic anhydride are particularly preferable. Moreover, the unsaturated carboxylic acid component (A1) should just be copolymerized in polyolefin resin (A), and the form is not limited. Examples of this form include random copolymerization, block copolymerization, and graft copolymerization (graft modification).

  Although it does not specifically limit as ethylene-type hydrocarbon component (A2), C2-C6 alkene, such as ethylene, propylene, isobutylene, 2-butene, 1-butene, 1-pentene, 1-hexene, is preferable, These A mixture of these may also be used. Among these, alkenes having 2 to 4 carbon atoms such as ethylene, propylene, isobutylene and 1-butene are more preferable, and ethylene and propylene are more preferable.

  Examples of the acrylic ester component or the methacrylic ester component (A3) include esterified products of (meth) acrylic acid and alcohols having 1 to 30 carbon atoms, and (meth) acrylic from the viewpoint of availability. An esterified product of an acid and an alcohol having 1 to 20 carbon atoms is preferable. Specific examples of such compounds include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, (meth) acrylic acid. Examples include octyl, decyl (meth) acrylate, lauryl (meth) acrylate, octyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, and the like. Mixtures of these may be used. Among these, from the viewpoint of adhesion to various substrates, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl acrylate, octyl acrylate are more preferable, and acrylic acid Ethyl and butyl acrylate are more preferable, and ethyl acrylate is particularly preferable. In addition, “(meth) acrylic acid˜” means “acrylic acid˜ or methacrylic acid˜”.

The polyolefin resin (A) is an acrylic ester component or a methacrylic ester component (A3) component within the range of the above formula (ii), that is, the entire resin [(A1) + (A2) + (A3)]. It is necessary to contain 28 % by mass or more and 35 % by mass or less. When the content of the component (A3) is less than 23% by mass, the effect of improving the adhesiveness and heat sealability when combined with another polyolefin resin (B) is small. On the other hand, when the content of the component (A3) exceeds 40% by mass, not only the production of the resin becomes difficult, but the adhesion to the polyolefin substrate may be lowered .

  The polyolefin resin (A) may contain the following components with an upper limit of 25% by mass. Namely, alkenes having 6 or more carbon atoms such as 1-octene and norbornenes; dienes such as butadiene and isoprene; maleic esters such as dimethyl maleate, diethyl maleate and dibutyl maleate; (meth) acrylic acid amide Alkyl vinyl ethers such as methyl vinyl ether and ethyl vinyl ether; obtained by saponifying vinyl esters such as vinyl formate, vinyl acetate, vinyl propionate, vinyl pivalate, vinyl versatate and vinyl esters with basic compounds, etc. 2-hydroxyethyl acrylate; glycidyl (meth) acrylate; (meth) acrylonitrile; styrene; substituted styrene; halogenated vinyls; halogenated vinylidenes; carbon monoxide; It can have. These mixtures may be contained. These components may be copolymerized in the polyolefin resin (A). The form is not particularly limited, and examples thereof include random copolymerization, block copolymerization, and graft copolymerization (graft modification).

The polyolefin resin (A) and combined with other polyolefin resin (B), Ru polyolefin resin der other than the composition of the polyolefin resin (A). For example, ethylene, propylene, 2 - butene, 1-butene emissions of any hydrocarbon without problems as long as a main component, or may be a copolymer thereof (random, block, graft, etc.).

The polyolefin resin (B) needs to contain the same unsaturated carboxylic acid component (B1) as the unsaturated carboxylic acid component (A1) described above. When the unsaturated carboxylic acid component ( B1 ) is not contained, it is difficult to make the resin aqueous (liquefied) without adding a non-volatile compound such as a surfactant. The content of the unsaturated carboxylic acid component ( B1 ) in the polyolefin resin (B) is 0 . It is necessary to be 1 to 7% by mass.

In the polyolefin resin (B), (meth) acrylic acid ester component (B3) such as methyl (meth) acrylate, ethyl (meth) acrylate, and butyl (meth) acrylate is contained up to 25% by mass. It is necessary to These mixtures may be contained. These components may be copolymerized in the other polyolefin resin (B). The form is not particularly limited, and examples thereof include random copolymerization, block copolymerization, and graft copolymerization (graft modification).

If Shimese Specific examples of the polyolefin resin (B), Po Li olefin resin (A) of unsaturated carboxylic acid-containing ethylene are not included in the composition - (meth) acrylic acid ester resin or an unsaturated carboxylic acid containing a propylene - (meth ) Acrylic acid ester resin, unsaturated carboxylic acid-containing ethylene-propylene- (meth) acrylic acid ester resin, unsaturated carboxylic acid-containing ethylene-butene- (meth) acrylic acid ester resin, unsaturated carboxylic acid-containing propylene-butene- ( meth) acrylic acid ester resin, unsaturated carboxylic acid-containing ethylene - propylene - butene - (meth) acrylic acid ester resins. Among them, polypropylene, adhesion of polyethylene terephthalate material, from the viewpoint of improvement in heat sealability is high, the unsaturated carboxylic acid-containing ethylene - (meth) acrylic acid ester resin, unsaturated carboxylic acid-containing ethylene - propylene - (meth ) Acrylic ester resin, unsaturated carboxylic acid-containing propylene-butene- (meth) acrylic ester resin, and unsaturated carboxylic acid-containing ethylene-propylene-butene- (meth) acrylic ester resin are more preferred.

  The polyolefin resin (A) and / or other polyolefin resin (B) may be chlorinated. In this case, the chlorination rate is suitably 5 to 50% by mass. The method for chlorination is not particularly limited, and a known method can be used. For example, after the resin to be chlorinated is dissolved in a chlorinated solvent such as chloroform, chlorination is performed by blowing gaseous chlorine while irradiating ultraviolet rays or in the presence of a radical generator. Can do.

  The mass ratio (A) / (B) between the polyolefin resin (A) and the other polyolefin resin (B) is preferably 1/99 to 60/40 from the viewpoint of adhesiveness and heat sealability. / 99 to 50/50 is more preferable, 2/98 to 50/50 is further preferable, and 3/97 to 40/60 is particularly preferable. When the content of (A) is less than 1% by mass, the effect of improving adhesiveness and heat sealability is small. Conversely, when the content exceeds 60% by mass, the adhesiveness and heat sealability tend to decrease.

  As the polyolefin resin (A), a resin having a melt flow rate of 0.01 to 10,000 g / 10 min at a load of 190 ° C. or 230 ° C. and 21.2 N (2160 g), which is a measure of molecular weight, can be used. The melt flow rate under these conditions is preferably 0.01 to 1000 g / 10 min, more preferably 0.1 to 500 g / 10 min, still more preferably 1 to 300 g / 10 min, and particularly preferably 1 to 200 g / min. 10 minutes. When the melt flow rate of the polyolefin resin (A) is less than 0.01 g / 10 min, it becomes difficult to make the resin water-based. On the other hand, when the melt flow rate of the polyolefin resin (A) exceeds 10,000 g / 10 min, the coating film is likely to be hard even if it is hard, and the adhesiveness to the base material and the heat sealability tend to be lowered. The molecular weight and melt flow rate of the other polyolefin resin (B) are not particularly limited.

  In the aqueous adhesive of the present invention, in order to further improve various coating film performances such as water resistance and boil resistance, a crosslinking agent is added in an amount of 0.1 to 50 with respect to 100 parts by mass of the resin in the aqueous dispersion. Part by mass, preferably 0.5 to 30 parts by mass can be added. When the addition amount of the crosslinking agent is less than 0.1 parts by mass, the degree of improvement in coating film performance is small, and when it exceeds 30 parts by mass, the coating film performance such as liquid stability and workability of the aqueous adhesive is low. It will decline. As the crosslinking agent, a crosslinking agent having self-crosslinking property, a compound having a plurality of functional groups that react with a carboxyl group in the molecule, a metal complex having a polyvalent coordination site, and the like can be used. Of these, isocyanate compounds, melamine compounds, urea compounds, epoxy compounds, carbodiimide compounds, oxazoline group-containing compounds, aziridine compounds, zirconium salt compounds, silane coupling agents, and the like are preferable. You may use combining these crosslinking agents. Among the above crosslinking agents, an isocyanate compound and an epoxy compound are preferable, and an isocyanate compound is particularly preferable from the viewpoint of improving various coating film performances such as water resistance and boil resistance.

  As the isocyanate compound, a polyfunctional isocyanate compound is preferable, and an aqueous (water-soluble or water-dispersible) one is more preferable. Aqueous polyfunctional isocyanate compounds can be obtained as commercial products, for example, trade names manufactured by BASF: BASONAT PLR8878, Bassonate HW-100, etc. Bihijole VPLS2150 / 1, SBU Isocyanate L801, Desmodur N3400, Desmodur VPLS2102, Desmodule VPLS2025 / 1, SBU Isocyanate 0772, Desmodur DN, etc., trade names of Takeda Pharmaceutical Co., Ltd .: Takenate WD720, Takenate WD725, Takenate WD730, etc., trade names of Asahi Kasei Kogyo Co., Ltd .: Duranate WB40-100, Duranate WB40-80D, Duranate WX- 741, and the like. Among these, Bihydur 3100, Desmodur DN, and Vasonate HW-100, which are modified products of hexamethylene diisocyanate, are particularly preferable.

To the aqueous adhesive of the present invention, an aqueous dispersion of another polymer, a tackifier component, and the like can be further added.
The aqueous dispersion of another polymer is not particularly limited. For example, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, ethylene- (meth) acrylic acid copolymer, styrene-maleic acid resin, styrene-butadiene resin, butadiene resin, acrylonitrile-butadiene Examples include aqueous dispersions such as resins, poly (meth) acrylonitrile resins, (meth) acrylamide resins, chlorinated polyethylene resins, chlorinated polypropylene resins, polyester resins, modified nylon resins, urethane resins, phenol resins, silicone resins, and epoxy resins. be able to. You may use these in mixture of 2 or more types.

  As the tackifier component, at least one component selected from rosins, terpenes, petroleum resins, coumarone resins, and indene resins can be used. As rosins, polymerized rosin, disproportionated rosin, hydrogenated rosin, maleated rosin, fumarated rosin, and glycerin ester, pentaerythritol ester, methyl ester, ethyl ester, butyl ester, ethylene glycol ester, diethylene glycol ester And triethylene glycol ester. Examples of the terpenes include low-polymerized terpene, α-pinene polymer, β-pinene polymer, terpene phenol, aromatic modified terpene, hydrogenated terpene, and the like. As petroleum resins, petroleum resins obtained by polymerizing petroleum fractions having 5 carbon atoms, petroleum resins obtained by polymerizing petroleum fractions having 9 carbon atoms, and petroleum resins obtained by hydrogenating them, these are modified with maleic acid, phthalic acid Examples include modified petroleum resins.

  In the aqueous adhesive of the present invention, the carboxyl group in the polyolefin resin (A) and the other polyolefin resin (B) needs to be partially neutralized with the basic compound (C). By the basic compound (C), the carboxyl group or the acid anhydride group is anionized, and the electrostatic repulsion of the anion prevents aggregation between the resin fine particles in the aqueous medium, thereby achieving good dispersion. The amount of the basic compound (C) added is 0.3 to the carboxyl group in the polyolefin resin (A) and the other polyolefin resin (B) (1 mol of acid anhydride group is regarded as 2 mol of carboxyl group). It is preferably 3 times equivalent, more preferably 0.5 to 2 times equivalent, and particularly preferably 0.6 to 1.5 times equivalent. If the amount is less than 0.3 equivalents, the effect of adding the basic compound (C) is not recognized. If the amount exceeds 3 equivalents, the problem of the odor of the adhesive may occur, or a coating film or an adhesive layer may be formed. There is a problem that the drying time becomes long.

  As such a basic compound (C), ammonia or an organic amine compound that volatilizes during film formation is preferable from the viewpoint of the water resistance and boil resistance of the coating film. Among them, the boiling point is 30 to 250 ° C., and further 50 Organic amine compounds at ˜200 ° C. are preferred. When the boiling point is less than 30 ° C., the rate of volatilization when the resin described later becomes aqueous may increase, and the aqueous formation may not proceed completely. When the boiling point exceeds 250 ° C., it becomes difficult to scatter the organic amine compound from the resin coating by drying, and the water resistance and boil resistance of the coating may be deteriorated.

  Specific examples of the organic amine compound include triethylamine, N, N-dimethylethanolamine, aminoethanolamine, N-methyl-N, N-diethanolamine, isopropylamine, iminobispropylamine, ethylamine, diethylamine, and 3-ethoxypropylamine. , 3-diethylaminopropylamine, sec-butylamine, propylamine, methylaminopropylamine, 3-methoxypropylamine, monoethanolamine, morpholine, N-methylmorpholine, N-ethylmorpholine and the like.

Next, the manufacturing method of the aqueous adhesive of this invention is demonstrated.
The method for producing the aqueous adhesive of the present invention is not particularly limited. First, an aqueous dispersion of the polyolefin resin (A) and an aqueous dispersion of another polyolefin resin (B) are obtained, and various methods can be used as necessary. A method of mixing the additives is simple.

  Examples of the method for producing an aqueous dispersion of polyolefin resin (A) and an aqueous dispersion of other polyolefin resin (B) include, for example, polyolefin resin (A), polyolefin resin (B), basic compound (C), and aqueous medium. And if necessary, a method of heating and stirring other components using a device widely known to those skilled in the art as a solid / liquid stirring device or an emulsifier can be adopted. The stirring method and the rotation speed of stirring are not particularly limited. For example, after putting each raw material into the tank of the apparatus, preferably stirring and mixing at a temperature of 40 ° C. or lower, and then continuing stirring at a temperature of 50 to 200 ° C. for 5 to 120 minutes. The aqueous dispersion of the polyolefin resin (A) and the other polyolefin resin (B) can be obtained by making the resin sufficiently aqueous and then cooling to 40 ° C. or lower with stirring.

  When stirring the raw material, it is preferable to add a water-soluble organic solvent for the purpose of smoothly making the aqueous solution. By using an organic solvent, an aqueous dispersion of polyolefin resins (A) and (B) can be obtained without adding a surfactant. As such an organic solvent, those having a solubility in water at 20 ° C. of 20 g / L or more are preferably used. The addition amount in the case of using an organic solvent is preferably about 1 to 40 parts by mass with respect to 100 parts by mass of the aqueous dispersion of polyolefin resins (A) and (B). The organic solvent can be removed (stripped) out of the system by heating the aqueous dispersion with stirring under normal pressure or reduced pressure. The final amount of the organic solvent is preferably 30% by mass or less, more preferably 3% by mass or less from the viewpoint of the environment with respect to 100 parts by mass of the aqueous dispersion of polyolefin resins (A) and (B). The content is preferably 0 to 1% by mass.

  Specific examples of the organic solvent used include methanol, ethanol, n-propanol, isopropanol, n-butanol, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, dioxane, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, and the like. Is mentioned. Among these, ethanol, isopropanol, and n-propanol, which are organic solvents having a hydroxyl group, are particularly preferable from the viewpoint of low temperature drying property.

  The number average particle diameter (hereinafter referred to as “mn”) of the polyolefin resin (A) particles in the aqueous adhesive of the present invention is preferably 1 μm or less from the viewpoint of improving liquid stability. From the viewpoint of the smoothness of the coating film formed by the agent, it is more preferably 0.5 μm or less, further preferably 0.3 μm or less, and most preferably 0.2 μm or less. Furthermore, the weight average particle diameter (hereinafter referred to as “mw”) is preferably 1 μm or less, more preferably 0.5 μm or less, and particularly preferably 0.3 μm or less. By reducing the particle diameter, the smoothness of the coating film is improved. The degree of particle dispersion (mw / mn) is preferably 1 to 5, more preferably 1 to 2, and more preferably 1 to 2, from the viewpoints of liquid stability and coating smoothness. Particularly preferred. The lower limit of the particle diameter is not particularly limited, but usually both mn and mw are about 0.01 μm. Such a particle diameter can be achieved, for example, by adopting the above-described production method.

  The aqueous adhesive of the present invention can be obtained by mixing the aqueous dispersion of polyolefin resin (A) obtained as described above and the aqueous dispersion of other polyolefin resin (B) at a predetermined ratio. it can. Furthermore, what is necessary is just to mix additives, such as a crosslinking agent, as needed.

  The resin content in the water-based adhesive is not particularly limited and is appropriately adjusted depending on the film forming conditions, the thickness and performance of the target resin layer, and the like. However, it is preferably 1 to 50% by mass, more preferably 3 to 50% by mass, and more preferably 5 to 45% in terms of maintaining the viscosity of the adhesive moderately and expressing good primer layer forming ability. It is more preferable that it is mass%, and it is especially preferable that it is 5-40 mass%.

  According to the present invention, the amount of the surfactant used in the aqueous adhesive of the present invention can be reduced by adopting the above production method, so that the aqueous adhesive does not substantially contain the surfactant. You can also Here, “substantially no surfactant” means that no surfactant is used during the production of the water-based adhesive (when the resin is dispersed), and the resulting adhesive is consequently a surfactant. Means that it does not contain.

  A pigment or dye may be added to the water-based adhesive of the present invention depending on the purpose of use, or the water-based adhesive of the present invention may be added to a commercially available paint or ink. The pigment or dye to be used is not particularly limited, and a commonly used pigment or dye may be appropriately selected depending on the type of paint or ink. Examples of pigments include inorganic pigments such as titanium dioxide, zinc oxide, chromium oxide, cadmium sulfide, calcium carbonate, barium carbonate, barium sulfate, clay, talc, yellow lead, iron oxide, carbon black, azo series, diazo series, and condensation. Examples thereof include organic pigments such as azo, thioindigo, indanthrone, quinacridone, anthraquinone, benzimidazole, perylene, perinone, phthalocyanine, halogenated phthalocyanine, anthrapyridine, and dioxazine. Examples of the dye include a direct dye, a reactive dye, an acid dye, a cationic dye, a vat dye, and a mordant dye. The above pigments or dyes may be contained alone or in combination of two or more.

  Furthermore, various agents such as a leveling agent, an antifoaming agent, an anti-waxing agent, a pigment dispersant, and an ultraviolet absorber can be added to the aqueous adhesive of the present invention as necessary. It is also possible to add organic or inorganic compounds other than those described above within a range not impairing the storage stability of the aqueous adhesive.

  Since the aqueous adhesive of the present invention is excellent in film forming ability, known film forming methods such as gravure roll coating, reverse roll coating, wire bar coating, lip coating, air knife coating, curtain flow coating, spray coating, The surface of various substrates can be uniformly coated by dip coating, brush coating, or the like. And after setting this coated thing near room temperature as needed, it is subjected to heat treatment for drying or drying and baking to form a uniform resin coating on the surface of various substrates. be able to. As a heating device at this time, a normal hot air circulation type oven, an infrared heater, or the like may be used. Further, the heating temperature and the heating time are appropriately selected depending on the characteristics of the base material, the kind of the crosslinking agent, the blending amount, and the like, and are not particularly limited. be able to. Moreover, in order to advance a crosslinking reaction, you may perform an aging process at about 20-60 degreeC.

  Since the aqueous adhesive of the present invention has good adhesion to various materials, it is possible to form a good coating film and adhesive layer by removing the aqueous medium from the aqueous adhesive by the coating treatment as described above. Can do.

  Examples of the substrate to which the aqueous adhesive of the present invention is applied include paper, synthetic paper, various thermoplastic resin films and molded articles, glass, metal, aluminum foil, plastic, and the like, and are not particularly limited. However, since the water-based adhesive of the present invention can provide excellent adhesion even under heat treatment under relatively low temperature conditions, a substrate having a relatively low heat resistance, for example, a thermoplastic resin (polypropylene having a melting point of 180 ° C. or less). , Polyethylene, etc.). And among these, a synthetic paper and a thermoplastic resin film are preferable as a base material, and a thermoplastic resin film is especially preferable.

  The thermoplastic resin film as the base material is polyamide resin such as nylon 6, nylon 66, nylon 46; polyethylene terephthalate, polyethylene naphthalate, polytrimethylene terephthalate, polytrimethylene naphthalate, polybutylene terephthalate, polybutylene naphthalate, etc. Polyester resins of: aliphatic polyester resins such as polyethylene succinate, polyglycolic acid and polylactic acid; polyolefin resins such as polypropylene and polyethylene; polyimide resins; polycarbonate resins; polyarylate resins; The laminated body of this is mentioned. The thermoplastic resin film may be an unstretched film or a stretched film, and the production method is not limited. The thickness of the thermoplastic resin film is not particularly limited, but a film having a thickness of 5 to 500 μm is usually used.

  The thermoplastic resin film may contain a filler. The filler is preferably an inorganic one, and examples include calcium carbonate, clay, silica, diatomaceous earth, talc, titanium oxide, barium titanate, barium sulfate, and alumina.

  The thermoplastic resin film may be subjected to various functional treatments such as various barrier coatings, easy adhesion coatings, antistatic coatings, ultraviolet shielding coatings, and various vapor deposition treatments such as silica, alumina, and aluminum. The water-based adhesive of the present invention has good adhesion to the surface subjected to the above treatment.

  The coating film formed by removing the aqueous medium from the aqueous adhesive of the present invention is preferably provided as an adhesive layer on the substrate described above (such as a thermoplastic resin film. The thickness of the adhesive layer is particularly limited). However, it is preferably 0.5 to 10 μm, more preferably 1 to 8 μm, still more preferably 1 to 6 μm, and particularly preferably 1.5 to 5 μm. If it is less than 5 μm, the effect as an adhesive is small (laminate strength is low), and conversely if it exceeds 10 μm, the drying time becomes long.

Furthermore, a laminated body can be comprised by bonding a to-be-adhered body through the said contact bonding layer. As the adherend, the same material as the base material described above can be used.
The bonding condition at that time is not particularly limited, but the temperature condition is preferably 60 ° C. or more and the resin melting point or less of the thermoplastic resin film. Examples of the laminating method include a method of laminating while applying pressure with a hot roll.

Hereinafter, the present invention will be described specifically by way of examples. However, the present invention is not limited by these.
In the following examples and comparative examples, various properties were measured or evaluated by the following methods.

1. Characteristics of polyolefin resin (1) Composition of resin
^{It was determined from 1} H-NMR analysis (analyzer manufactured by Varian, 300 MHz). Orthodichlorobenzene (d ₄ ) was used as a solvent, and measurement was performed at 120 ° C.

(2) Melt flow rate It measured by the method (190 degreeC, 21.2N (2160g) load) as described in JISK6370.

(3) Weight average molecular weight Using GPC analysis (HLC-8020 type device manufactured by Tosoh Corporation, column is TSK-GEL), a sample was dissolved in tetrahydrofuran, measured at 40 ° C., and a calibration standard prepared with a polystyrene standard sample The weight average molecular weight was determined from the line.

2. Characteristics of aqueous dispersion of polyolefin resin and aqueous adhesive (1) Concentration of solid content of aqueous dispersion An appropriate amount of the aqueous dispersion was weighed and heated at 150 ° C. until the mass of the residue (solid content) reached a constant weight. The mass of the solid content was determined, and the solid content concentration was determined.

(2) Average particle size of aqueous dispersion Nikkiso Co., Ltd., Microtrac particle size distribution meter, model: UPA150 (MODEL No. 9340, dynamic light scattering method), number average particle size mn and weight average particle size mw Asked. The refractive index of the resin used for particle diameter calculation was 1.50.

3. Material characteristics In the following evaluation, as a thermoplastic resin film, a biaxially stretched polyethylene terephthalate film (manufactured by Unitika Ltd., product name: emblet PET12, thickness 12 μm, hereinafter referred to as “PET”), biaxially stretched nylon 6 film ( Unitika, product name: emblem, thickness 15 μm, hereinafter referred to as “Ny”, stretched polypropylene film (manufactured by Tosero, thickness 50 μm, hereinafter referred to as “PP”), unstretched polyethylene film (made by Tamapoly, thickness) 40 μm, hereinafter referred to as “PE”).

(1) Water resistance evaluation method of coating film A water-based adhesive is coated on the above PET film using a Mayer bar so that the thickness of the adhesive layer after drying is 2 μm, and then dried at 90 ° C. for 1 minute. I let you. The obtained coated film was allowed to stand at 40 ° C. for one day and then immersed in warm water at 60 ° C. for 24 hours. And the state of the coating film after air drying was evaluated visually according to the following criteria.

○: No change Δ: The coating film is cloudy ×: The coating film is completely dissolved or peeled off

(2) Adhesive evaluation of base material / adhesive layer After coating a water-based adhesive on various base materials using a Meyer bar so that the thickness of the adhesive layer after drying becomes 2 μm, at 90 ° C. for 1 minute, It was made to dry and the laminated body of the base material and the contact bonding layer was obtained. The obtained laminate was allowed to stand at room temperature for a day, and then a cellophane tape (manufactured by Nichiban Co., Ltd., product number: TF-12) was attached to the surface, and the degree of peeling when the tape was peeled off at a stroke was visually determined as follows. Evaluated by criteria.

○: No peeling at all △: Some peeling off ×: All peeling off

The production conditions and treatment conditions of the various film laminates used in the evaluations of (3) and (4) below were as follows.
[Bonding conditions]
The aqueous adhesive was coated on the above PET film or Ny film with a Mayer bar so that the thickness of the adhesive layer after drying was 3 μm, and dried at 90 ° C. for 1 minute. A PP film is bonded to the adhesive-coated surface of the PET film, a PE film is bonded to the adhesive-coated surface of the Ny film, and a heat press machine is used at a sealing pressure of 0.3 MPa for 2 seconds. Pressed at ° C.

[Boil processing]
The obtained PET film / PP film laminate was immersed in hot water at 98 ° C. for 30 minutes, and then cooled to room temperature for evaluation.

(3) Measurement of peel strength After various treatments were applied to the film laminate, it was cut out with a width of 15 mm to obtain a measurement sample, and a tensile tester (manufactured by Intesco, precision universal material tester type 2020) was used, and a tensile rate of 200 mm / The peel strength of the coating film was measured at a tensile angle of 180 degrees.

(4) Boil resistance (appearance)
About the laminated film, the external appearance of the film after a boil process was observed visually, and the following reference | standard evaluated.

○: No change Δ: Adhesive layer whitens but no bubbles ×: Bubbles enter

(Production of polyolefin resin P-1)
100 g of propylene-butene-ethylene terpolymer (manufactured by Huls Japan, product name: Best Plast 708, propylene / butene / ethylene = 65/24/11% by mass) and 500 g of toluene, a stirrer and a cooling tube In a four-necked flask equipped with a dropping funnel, the mixture was heated and melted in a nitrogen atmosphere. Then, the system temperature was maintained at 110 ° C., and a solution of 1.0 g of dicumyl peroxide in 20 g of heptane was added as a radical generator over 1 hour with stirring. Thereafter, 7.0 g of maleic anhydride, 9.0 g of lauryl acrylate, and 10 g of heptane containing 0.5 g of dicumyl peroxide were added dropwise over 1 hour as an unsaturated carboxylic acid, followed by reaction for 30 minutes. After completion of the reaction, the reaction mixture was cooled to room temperature, and then the obtained reaction product was put into a large amount of acetone to precipitate a resin. This resin was further washed several times with acetone to remove unreacted substances, and then dried under reduced pressure in a vacuum dryer to obtain polyolefin resin P-1. The weight average molecular weight of P-1 was 50,000, and the content of lauryl acrylate in the resin was 6% by mass.

The following commercially available thing was used for the other polyolefin resin.
・ Arkema, product name: Bondine AX-8390
・ Product name: Bondine HX-8290, manufactured by Sumitomo Chemical Co., Ltd.
・ Product name: Bondine HX-8210, manufactured by Sumitomo Chemical Co., Ltd.
Table 1 shows the composition of these polyolefin resins.

(Production of aqueous polyolefin resin dispersion E-1)
Using a stirrer equipped with a hermetic pressure-resistant 1 liter glass container with a heater, 60.0 g of polyolefin resin [manufactured by Arkema, product name: Bondine AX-8390, polyolefin resin (A)] and water-soluble organic 100.0 g of n-propanol (manufactured by Wako Pure Chemical Industries) as a solvent, 2.5 g of triethylamine (manufactured by Wako Pure Chemical Industries) as a basic compound (C), and 137.5 g of distillation as an aqueous medium Water was charged into the glass container and stirred at a rotational speed of the stirring blade of the stirrer at 300 rpm. No sedimentation of resin particles was observed at the bottom of the container, confirming that it was in a floating state. It was. Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, the system temperature was kept at 120 ° C. and further stirred for 20 minutes. Then, it cooled to room temperature (about 25 degreeC), stirring with air cooling with the rotational speed of 300 rpm. After that, pressure filtration (air pressure 0.2 MPa) was performed with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave) to obtain a milky white uniform polyolefin resin aqueous dispersion E-1. Various characteristics of this aqueous dispersion are shown in Table 2.

(Production of aqueous polyolefin resin dispersion E-2)
Using a stirrer equipped with a hermetic pressure-resistant 1 liter glass container with a heater, 60.0 g of polyolefin resin [manufactured by Sumitomo Chemical Co., Ltd., product name: Bondine HX-8290, polyolefin resin (B)] and water-soluble 60.0 g of isopropanol (manufactured by Wako Pure Chemical Industries, Ltd.) as an organic solvent, 2.2 g of triethylamine (manufactured by Wako Pure Chemical Industries, Ltd.) as a basic compound (C), and 177.8 g of distillation as an aqueous medium When water was charged into the glass container and stirred at a rotational speed of the stirring blade of 300 rpm, no precipitation of resin particles was observed at the bottom of the container, confirming that it was in a floating state. Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, the system temperature was kept at 120 ° C. and further stirred for 20 minutes. Then, it cooled to room temperature (about 25 degreeC), stirring with air cooling with the rotational speed of 300 rpm. Then, pressure filtration (air pressure 0.2 MPa) was performed with a 300-mesh stainless steel filter (wire diameter 0.035 mm, plain weave) to obtain a milky white uniform polyolefin resin aqueous dispersion E-2. Various characteristics of this aqueous dispersion are shown in Table 2.

(Production of aqueous polyolefin resin dispersion E-3)
Using a stirrer equipped with a hermetic pressure-resistant 1 liter glass container with a heater, 60.0 g of polyolefin resin P-1 [polyolefin resin (B)] and 90.0 g of n as a water-soluble organic solvent -Propanol (manufactured by Wako Pure Chemical Industries, Ltd.), 3.9 g of N, N-dimethylethanolamine (manufactured by Wako Pure Chemical Industries, Ltd.) as the basic compound (C), and 146.1 g of distilled water as an aqueous medium, Was stirred in the glass container and the stirring blade was rotated at a rotational speed of 300 rpm. No resin precipitation was observed at the bottom of the container, and it was confirmed that the container was in a floating state. Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, the system temperature was kept at 140 ° C. and further stirred for 60 minutes. Then, it cooled to room temperature (about 25 degreeC), stirring with air cooling with the rotational speed of 300 rpm. Then, pressure filtration (air pressure 0.2 MPa) was performed with a 300-mesh stainless steel filter (wire diameter 0.035 mm, plain weave) to obtain a milky-yellow uniform polyolefin resin aqueous dispersion E-3. Various characteristics of this aqueous dispersion are shown in Table 2.

(Production of aqueous polyolefin resin dispersion E-4)
Using a stirrer equipped with a hermetic pressure-resistant 1 liter glass container with a heater, 60.0 g of polyolefin resin [manufactured by Sumitomo Chemical Co., Ltd., product name: Bondine HX-8210, polyolefin resin (B)] and water-soluble 60.0 g of isopropanol (manufactured by Wako Pure Chemical Industries, Ltd.) as an organic solvent, 2.2 g of triethylamine (manufactured by Wako Pure Chemical Industries, Ltd.) as a basic compound (C), and 177.8 g of distillation as an aqueous medium When water was charged into the glass container and stirred at a rotational speed of the stirring blade of 300 rpm, no precipitation of resin particles was observed at the bottom of the container, confirming that it was in a floating state. Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, the system temperature was kept at 120 ° C. and further stirred for 20 minutes. Then, it cooled to room temperature (about 25 degreeC), stirring with air cooling with the rotational speed of 300 rpm. Then, pressure filtration (air pressure 0.2 MPa) was performed with a 300-mesh stainless steel filter (wire diameter 0.035 mm, plain weave) to obtain a milky white uniform polyolefin resin aqueous dispersion E-4. Various characteristics of this aqueous dispersion are shown in Table 2.

Example 1
Polyolefin resin aqueous dispersions E-1 and E-2 were blended so that E-1 / E-2 was 30/70 in terms of solid content, mixed and stirred at room temperature for 5 minutes, and aqueous adhesive W-1 was obtained. Various performance evaluation was performed using this W-1.

Examples 2-4
The aqueous polyolefin resin dispersions E-1 and E-2 were mixed at a solid content mass ratio of E-1 / E-2 of 10/90 (Example 2), 50/50 (Example 3), 70/30 ( Example 4) was formulated, and aqueous adhesives W-2, W-3, and W-4 were obtained in the same manner as in Example 1. Various performance evaluations were performed using these W-2 to W-4.

Examples 5-8
The polyolefin resin aqueous dispersions E-1 and E-3 were mixed at a solid mass ratio of E-1 / E-3 of 30/70 (Example 5), 10/90 (Example 6), and 50/50 ( Examples 7) and 70/30 (Example 8) were blended, and aqueous adhesives W-5, W-6, W-7, and W-8 were obtained in the same manner as in Example 1. Various performance evaluation was performed using these W-5 to W-8.

Example 9
A polyfunctional isocyanate compound as a cross-linking agent (manufactured by BASF, product name: Vasonate HW-100, isocyanate content of about 17% by mass, hereinafter referred to as “HW-100”) is adjusted to a concentration of 10% by mass using water. Diluted to The water-based adhesive W-1 obtained in Example 1 and the above isocyanate compound diluent are blended so that HW-100 is 5 parts by mass with respect to 100 parts by mass in total of the polyolefin resin. Water mixing adhesive W-9 was obtained by mixing and stirring for minutes. Various performance evaluations were performed using this W-9.

Example 10
Instead of the aqueous adhesive W-1 of Example 9, the aqueous adhesive W-5 obtained in Example 5 was used. And other than that was carried out similarly to Example 9, and obtained the water-based adhesive W-10. Various performance evaluations were performed using this W-10.

Comparative Examples 1-3
Aqueous adhesive H-1 (Comparative Example 1), respectively, using a single polyolefin resin aqueous dispersion E-1 (Comparative Example 1), E-2 (Comparative Example 2), E-3 (Comparative Example 3), H-2 (Comparative Example 2) and H-3 (Comparative Example 3) were obtained. Various performance evaluations were performed using these H-1 to H-3.

Comparative Examples 4 and 5
Instead of aqueous polyolefin resin dispersion E-1 (using polyolefin resin (A)) in Examples 1 and 5, polyolefin resin aqueous dispersion E-4 (resin not corresponding to polyolefin resin (A), ie, resin (A) using a resin having a composition in a range other than the predetermined range that defines the composition of (A). Other than that, aqueous adhesives H-4 (Comparative Example 4) and H-5 (Comparative Example 5) were obtained in the same manner as in Example 1. Various performance evaluation was performed using these H-4 and H-5.

  The results of Examples 1 to 10 and Comparative Examples 1 to 5 are shown in Tables 3 and 4.

  The water-based adhesives W-1 to W-8 containing the polyolefin resin (A) having a specific composition and other polyolefin resins (B) in Examples 1 to 8 The adhesiveness was good and the adhesive strength was excellent. What should be noted is that, in comparison with Comparative Examples 1 to 3, the polyolefin resins (A) and (B) contain both of the polyolefin resins (A) and (B) as compared to the case where each of the polyolefin resins (A) and (B) is used alone. That is, the peel strength was dramatically improved. Furthermore, as is apparent from the results of Examples 1 to 3 and Examples 5 to 7, this effect of improving the peel strength was remarkably recognized when a specific amount of the polyolefin resin (A) was contained. Moreover, this adhesive strength improvement effect was recognized even if the composition of other polyolefin resin (B) changed. Furthermore, the improvement of boil resistance was confirmed by adding a crosslinking agent (Examples 9 and 10).

  On the other hand, even when a polyolefin resin other than the composition of the polyolefin resin (A) was used, the effect of improving the adhesive strength as in the examples of the present invention was not recognized, and conversely, the adhesive strength was lowered (Comparative Examples 4 and 5).

Claims (5)

An unsaturated carboxylic acid component (A1), an ethylene-based hydrocarbon component (A2), and an acrylic acid ester component or a methacrylic acid ester (A3), and the mass ratio of each component of (A1) to (A3) is as follows: A polyolefin resin (A) satisfying the formulas (i) and (ii);
0.1 to 7% by mass of the unsaturated carboxylic acid component (B1), and other polyolefin resin (B) containing 25% by mass or less of the acrylic acid ester component or the methacrylic acid ester (B3) ;
An aqueous adhesive comprising a basic compound (C) and an aqueous medium.
0.01 ≦ (A1) / {(A1) + (A2) + (A3)} × 100 ≦ 7 (i)
28 ≦ (A3) / {(A1) + (A2) + (A3)} × 100 ≦ 35 (ii)   The aqueous adhesive according to claim 1, wherein the mass ratio (A) / (B) of the polyolefin resin (A) to the other polyolefin resin (B) is from 1/99 to 60/40.   Furthermore, a crosslinking agent component is contained, and the amount thereof is 0.1 to 50 parts by mass with respect to 100 parts by mass of the total amount of the polyolefin resin (A) and the other polyolefin resin (B). The water-based adhesive according to 1 or 2.   A base material having a coating film formed by forming a coating film from the aqueous adhesive according to any one of claims 1 to 3 on the surface of the base material.   A laminate comprising the base material on which the coating film according to claim 4 is formed as an adhesive layer, and an adherend bonded to the base material through the adhesive layer. .