Aqueous resin compositions, coatings, adhesives, coating films, adhesive layers, and laminates

Abstract

The present invention provides an aqueous resin composition which contains a composite resin (A) and an aqueous medium (B), wherein the composite resin (A) contains a vinyl polymer (A1) and a polyester resin (A2). This aqueous resin composition is capable of forming a coating film that is initially homogeneous and finally forms a hydrophobic surface; and this aqueous resin composition is suitable for paper coating / impregnation, fibers / nonwoven fabrics, carpets, civil engineering building materials, mortar cement, automobile components, tire cords, coating materials, pastes, rust preventive coating, adhesives, plastic modification, powder puffs, electronic materials, adhesives (for general use), coating / impregnation (nonwoven fabric / paper), fiber impregnation / reinforcing fiber processing (carpets and the like), moisture-proofing / water-resistant coating, cement / mortar, building material processing / wooden material bonding, synthetic leather, artificial leather, gloves, contraception, receiving agents for inks, dispersant materials for inks and the like.

Description

Technical Field

[0001] The aqueous resin composition is used in a variety of applications such as paper coating / impregnation, fibers / non-woven fabrics, carpets, civil engineering building materials, mortar cement, automotive parts, tire cords, paints, pastes, rust-proof coatings, adhesives, plastic modification, cosmetic puffs, electronic materials, adhesives (general, for rubber), coating / impregnation (non-woven fabric / paper), fiber impregnation / reinforcing fiber processing (carpets, etc.), moisture-proof / water-resistant coatings, cement / mortar, building material processing / wood adhesion, synthetic leather, artificial leather, gloves, contraceptives, ink acceptors, ink dispersants, etc.

[0002] For the aqueous resin composition, various characteristics are required according to the application, and aqueous resin compositions combining different resins have been proposed. For example, Patent Document 1 describes an aqueous resin containing a block copolymer composed of a vinyl polymer segment and a polyurethane segment having an acid group neutralized with an acid group and / or a basic compound. Patent Document 2 describes a composition containing a latex obtained by seed polymerization of a diene-based unsaturated monomer in the presence of seed latex and an aqueous polyurethane. Patent Document 3 describes a resin composition containing a hydrogenated derivative of a hydroxyl group-containing conjugated diene polymer and another aqueous resin in the same micelle.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] The aforementioned composite resin is sometimes required to be homogeneous during coating but to exhibit adhesion between dissimilar substrates after curing. However, conventionally known composite resins primarily aim to form a homogeneous coating film by homogeneously mixing different resins at the molecular level, and no means are known for forming such a coating film. The present invention has been made in view of the above problem, and aims to provide an aqueous resin composition that is homogeneous during coating but ultimately exhibits adhesion between dissimilar substrates. [Means for solving the problem]

[0005] The inventors have discovered that in an aqueous resin composition containing a composite resin, by using a specific combination of resins in the composite resin, it is possible to form a coating film that is initially homogeneous but, upon heating, causes the resin to segregate, ultimately exhibiting adhesion between different types of substrates.

[0006] In other words, the present invention includes the following inventions. [1] An aqueous resin composition comprising a composite resin (A) and an aqueous medium (B), wherein the composite resin (A) comprises a vinyl polymer (A1) and a polyester resin (A2). [2] The aqueous resin composition according to [1], wherein the acid value of the polyester resin (A2) is 0.1 mg KOH / g or more and 100 mg KOH / g or less. [3] The aqueous resin composition according to [1] or [2], wherein the amount of aromatic rings contained in the polyester resin (A2) is 0.01 mol / kg or more and 20 mol / kg or less. [4] The aqueous resin composition according to any one of [1] to [3], wherein the mass ratio ((A1) / (A2)) of the vinyl polymer (A1) to the polyester resin (A2) is 0.001 or more and 3 or less. A coating agent comprising the aqueous resin composition described in any one of [5][1] to [4]. An adhesive comprising any one of the aqueous resin compositions described in [6], [1], to [4]. A coating film formed from any one of the aqueous resin compositions described in [7], [1], to [4]. An adhesive layer formed from any one of the aqueous resin compositions described in [8], [1], to [4]. A laminate having the coating film described in [9] and [7] or the adhesive layer described in [8]. [Effects of the Invention]

[0007] By using the aqueous resin composition of the present invention, it is possible to form a coating film that is initially homogeneous, but which undergoes segregation of the resin upon heating, ultimately exhibiting adhesion between different types of substrates. [Modes for carrying out the invention]

[0008] The aqueous resin composition of the present invention comprises a composite resin (A) and an aqueous medium (B), wherein the composite resin (A) comprises a vinyl polymer (A1) and a polyester resin (A2).

[0009] The vinyl polymer (A1) represents a polymer having units derived from a vinyl monomer (a). The vinyl monomer (a) represents a compound having at least one polymerizable vinyl bond in one molecule. One or more types of vinyl monomers (a) can be used, and examples include a conjugated diene compound (a1) and other vinyl compounds (a2).

[0010] The diene compound (a1) can be one or more types, such as 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, 1,3-heptadiene, 2,3-dimethylbutadiene, 2-phenyl-1,3-butadiene, 3-methyl-1,3-pentadiene, 2-chlor-1,3-butadiene, etc.

[0011] The content of the conjugated diene compound (a1) is preferably 1% by mass or more, more preferably 10% by mass or more, and even more preferably 30% by mass or more, with an upper limit of 100% by mass, based on the total amount of vinyl monomer (a).

[0012] The aforementioned other vinyl compound (a2) can be one or more types, such as alkyl(meth)acrylates having 4 to 22 carbon atoms, including methyl(meth)acrylate, ethyl(meth)acrylate, propyl(meth)acrylate, butyl(meth)acrylate, isobutyl(meth)acrylate, tert-butyl(meth)acrylate, pentyl(meth)acrylate, 3-methylbutyl(meth)acrylate, neopentyl(meth)acrylate, isoamyl(meth)acrylate, hexyl(meth)acrylate, heptyl(meth)acrylate, octyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, isooctyl(meth)acrylate, nonyl(meth)acrylate, dodecyl(meth)acrylate, tridecyl(meth)acrylate, stearyl(meth)acrylate, isostearyl(meth)acrylate, hexadecyl(meth)acrylate, etc.; Cycloalkyl(meth)acrylates with 6 to 20 carbon atoms, such as cyclopentyl(meth)acrylate, cyclohexyl(meth)acrylate, and isobornyl(meth)acrylate; Allyl (meth)acrylates such as phenyl (meth)acrylate; Aralkyl(meth)acrylates with 10 to 20 carbon atoms, such as benzyl(meth)acrylate and phenethyl(meth)acrylate; Allyloxyalkyl (meth)acrylates such as phenoxyethyl (meth)acrylate; Alkyl crotonic esters such as methyl crotonic acid and ethyl crotonic acid; Unsaturated dicarboxylate alkyl esters such as dimethyl maleate, dibutyl maleate, dimethyl fumarate, dibutyl fumarate, dimethyl itaconate, and dibutyl itaconate; Aromatic vinyl monomers such as styrene, p-tert-butylstyrene, α-methylstyrene, vinyltoluene, vinylpyridine, chlorostyrene, and chloromethylstyrene; (meth)acrylonitrile, crotononitrile, (meth)acrylamide, N-methyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, N-methylol(meth)acrylamide, N-methoxyethyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-dimethylaminoethyl(meth)acrylate, N,N-dimethylaminopropyl(meth)acrylamide, N,N-diethyl Nitrogen-containing monomers such as ethylaminoethyl (meth)acrylate, N,N-diethylaminopropyl (meth)acrylate, N-(meth)acryloylmorpholine, N-(meth)acryloylpyrrolidine, N-vinylformamide, N-vinylpyrrolidone, N-vinylimidazole, N-vinylcarbazole, N-vinylquinoline, and N-vinylpiperidine (preferably monosubstituted or disubstituted (meth)acrylamides (including those in which substituents are bonded to form a ring)) and methyl chloride salts of said nitrogen-containing monomers; Halogenated olefins such as vinyl fluoride, vinylidene fluoride, tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, vinyl chloride, and vinylidene chloride; α-olefins such as ethylene, propylene, isobutylene, and 1-butene; Vinyl carboxylates such as vinyl acetate, vinyl propionate, vinyl pivalate, vinyl versatate, vinyl benzoate, and vinyl neodecanoate; Alkyl vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, n-butyl vinyl ether, and isobutyl vinyl ether; cycloalkyl vinyl ethers such as cyclohexyl vinyl ether; Carbonyl group-containing monomers such as acrolein and methyl vinyl ketone; Polyoxyethylene group-containing (meth)acrylic monomers such as polyethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, polyethylene glycol polypropylene glycol copolymer (meth)acrylate, methoxypolyethylene glycol polypropylene glycol copolymer (meth)acrylate, polyethylene glycol polytetramethylene glycol copolymer (meth)acrylate, and methoxypolyethylene glycol polytetramethylene glycol copolymer (meth)acrylate; Fluoroalkyl group-containing monomers such as perfluorocyclohexyl (meth)acrylate, di-perfluorocyclohexyl fumarate, and N-isopropylfluorooctanesulfonamide ethyl (meth)acrylate; Unsaturated dicarboxylic acid anhydrides such as maleic anhydride, citraconic anhydride, mesaconic anhydride, itaconic anhydride, and tetrahydrophthalic anhydride; Cyclic ether-containing monomers such as glycidyl (meth)acrylate, allyl glycidyl ether, and tetrahydrofurfuryl (meth)acrylate; Silyl group-containing monomers such as vinylitrichlorosilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, and γ-(meth)acryloxypropyltrimethoxysilane; Hydroxy group-containing monomers such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and 2-hydroxyethyl allyl ether; Examples include vinyl group-containing sulfonic acid compounds such as vinyl sulfonic acid, 3-acryloxypropane-1-sulfonic acid, 3-acryloxyoctyloxybenzenesulfonic acid, 3-acryloxybenzenediazosulfonic acid, 3-acryloxyazobenzene-4'-sulfonic acid, 2-acryloylamino-2-methylpropane-1-sulfonic acid, 2-acryloylamide-2-methylpropanesulfonic acid, and acrylonitrile-tert-butylsulfonic acid, as well as salts thereof.

[0013] The content rate of the other vinyl compound (a2) is preferably 1% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more, preferably 80% by mass or less, more preferably 60% by mass or less, still more preferably 50% by mass or less in the total amount of the vinyl monomer (a).

[0014] The total content rate of the conjugated diene compound (a1) and the other vinyl compound (a2) is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, preferably 100% by mass or less in the total amount of the vinyl monomer (a).

[0015] The glass transition temperature of the vinyl polymer (A1) is preferably -100°C or higher, more preferably -80°C or higher, preferably 120°C or lower, more preferably 100°C or lower, still more preferably 50°C or lower, even more preferably 25°C or lower.

[0016] The glass transition temperature Tg(A1) of the vinyl polymer (A1) represents a value obtained by converting the glass transition temperature Tga at absolute temperature obtained by the following formula (FOX formula) into Celsius temperature. 1 / Tga = Σ(Wi / Tgi) ···

[0017] In the above formula, Tga represents the glass transition temperature (unit: absolute temperature) of the polymer composed of each vinyl monomer (a) used in the synthesis of the vinyl polymer (A1). Wi represents the mass ratio of each vinyl monomer (a) in the raw material of the vinyl polymer (A1). Tgi represents the glass transition temperature (unit: absolute temperature) of the homopolymer formed only from each vinyl monomer (a).

[0018] The details of the FOX formula are described in the Bulletin of the American Physical Society, Series 2, Volume 1, Number 3, page 123 (1956). Furthermore, the glass transition temperatures (Tgi) of various monomer homopolymers used in the FOX formula can be those found, for example, in "Coatings and Paints" (Paints Publishers, 10 (No. 358), 1982).

[0019] The content of the vinyl polymer (A1) in the composite resin (A) is preferably 0.1% by mass or more, more preferably 1% by mass or more, even more preferably 10% by mass or more, even more preferably 20% by mass or more, particularly preferably 30% by mass or more, preferably 90% by mass or less, more preferably 70% by mass or less, even more preferably 60% by mass or less, and even more preferably 50% by mass or less.

[0020] The polyester resin (A2) refers to a resin whose main chain is formed by a polyester skeleton, and examples include esterification reaction products of polyol (b1) and polycarboxylic acid (b2); ring-opening polymers of cyclic ester compounds such as ε-caprolactone; and copolymers thereof.

[0021] The polyol (b1) can be a low molecular weight polyol (for example, a polyol with a molecular weight of 50 or more and less than 300), and may also contain a polymer polyol (a polyol with a number average molecular weight of 300 or more).

[0022] As the low molecular weight polyol, polyols with a molecular weight of 50 to 300 can be used. Examples include aliphatic polyols with 2 to 6 carbon atoms such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, diethylene glycol, dipropylene glycol, neopentyl glycol, and 1,3-butanediol; polyols containing alicyclic structures such as 1,4-cyclohexanediol and cyclohexanedimethanol; and polyols containing aromatic structures such as bisphenol compounds like bisphenol A and bisphenol F, and their alkylene oxide adducts.

[0023] Examples of the polymer polyol include polyether polyols, polycarbonate polyols, and polyolefin polyols.

[0024] Examples of the aforementioned polyether polyol include those obtained by addition polymerization (ring-opening polymerization) of an alkylene oxide using one or more compounds having two or more active hydrogen atoms as initiators.

[0025] Examples of the initiators include linear diols such as ethylene glycol, diethylene glycol, triethylene glycol, trimethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and 1,6-hexanediol; branched diols such as neopentyl glycol; triols such as glycerin, trimethylolethane, trimethylolpropane, and pyrogallol; polyols such as sorbitol, sucrose, and aconite sugar; tricarboxylic acids such as aconitic acid, trimellitic acid, and hemimeric acid; phosphoric acid; polyamines such as ethylenediamine and diethylenetriamine; triisopropanolamine; phenolic acids such as dihydroxybenzoic acid and hydroxyphthalic acid; and 1,2,3-propanetrithiol.

[0026] Examples of the alkylene oxides include ethylene oxide, propylene oxide, butylene oxide, styrene oxide, epichlorohydrin, and tetrahydrofuran.

[0027] As the polyether polyol, it is preferable to use polyoxytetramethylene glycol obtained by addition polymerization (ring-opening polymerization) of tetrahydrofuran as the initiator.

[0028] Examples of the polycarbonate polyol include reaction products of carbonate esters and polyols, and reaction products of phosgene and bisphenol A, etc.

[0029] Examples of the aforementioned carbonate esters include methyl carbonate, dimethyl carbonate, ethyl carbonate, diethyl carbonate, cyclocarbonate, and diphenyl carbonate.

[0030] Examples of polyols that can react with the carbonate ester include the polyols exemplified above as low molecular weight polyols; and high molecular weight polyols such as polyether polyols (polyethylene glycol, polypropylene glycol, etc.) and polyester polyols (polyhexamethylene adipate, etc.) (for example, with a weight-average molecular weight of 500 to 5,000).

[0031] Examples of the aforementioned polyolefin polyols include polyisobutenoriol, hydrogenated polybutadiene polyol, and hydrogenated polyisoprene polyol.

[0032] Examples of the polycarboxylic acid (b2) include aliphatic polycarboxylic acids such as succinic acid, adipic acid, sebacic acid, and dodecanedicarboxylic acid; aromatic polycarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, and naphthalenedicarboxylic acid; and anhydrides or ester-forming derivatives of the aliphatic polycarboxylic acid and aromatic polycarboxylic acid.

[0033] The polyester resin (A2) preferably has hydrophilic groups. The presence of hydrophilic groups in the polyester resin (A2) improves the water dispersibility of the composite resin (A).

[0034] Examples of the hydrophilic group include anionic groups such as carboxyl groups and sulfonic acid groups; cationic groups such as tertiary amino groups and quaternary ammonium groups; and nonionic groups such as polyoxyethylene groups. Among these, groups having anionic properties are preferred.

[0035] Methods for imparting hydrophilic groups to the polyester resin (A2) include using a compound having hydrophilic groups as the low molecular weight polyol or polycarboxylic acid; and adding a dicarboxylic acid anhydride or the like to an esterification reaction product of the low molecular weight polyol and polycarboxylic acid, a ring-opening polymer of a cyclic ester compound, a copolymer thereof, etc.

[0036] Examples of the hydrophilic low molecular weight polyols include hydroxy acids such as 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2-dimethylolbutyric acid, and 2,2-dimethylolvaleric acid; and reaction products of the polyol having a carboxyl group and the polycarboxylic acid.

[0037] Examples of the aforementioned dicarboxylic acid anhydrides include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, chloride anhydride, methyltetrahydrophthalic anhydride, glutaric anhydride, cis-4-cyclohexen-1,2-dicarboxylic acid anhydride, trimellitic anhydride, and the like.

[0038] Examples of polycarboxylic acids having sulfonic acid groups include dicarboxylic acids having sulfonic acid groups such as 5-sulfoisophthalic acid, sulfoterephthalic acid, 4-sulfophthalic acid, 5-(4-sulfophenoxy)isophthalic acid, 5-sulfoisophthalic acid monoalkyl, and 5-sulfoisophthalic acid dialkyl; and alkali metal salts of the dicarboxylic acids having sulfonic acid groups.

[0039] Examples of low molecular weight polyols having cationic groups include N-methyl-diethanolamine and polyols having tertiary amino groups, such as polyols obtained by reacting a compound having two epoxy groups in one molecule with a secondary amine.

[0040] Examples of polyols having a nonionic group include polyols having a polyoxyethylene structure.

[0041] The polyester resin (A2) is preferably made to contain aromatic rings, from the viewpoint of adhesion to the substrate and other factors. By using a raw material that has aromatic rings, the polyester resin (A2) can be made to contain aromatic rings.

[0042] The aromatic ring content in the polyester resin (A2) is, for example, preferably 0.01 mol / kg or more, more preferably 0.05 mol / kg or more, more preferably 0.1 mol / kg or more, preferably 15 mol / kg or less, more preferably 10 mol / kg or less, even more preferably 8 mol / kg or less, and even more preferably 5 mol / kg or less.

[0043] The acid value of the polyester resin (A2) is, for example, 0.1 mg KOH / g or more, preferably 1 mg KOH / g or more, more preferably 5 mg KOH / g or more, preferably 100 mg KOH / g or less, more preferably 80 mg KOH / g or less, even more preferably 50 mg KOH / g or less, and even more preferably 30 mg KOH / g or less.

[0044] The weight-average molecular weight of the polyester resin (A2) is preferably 500 or more, more preferably 1,000 or more, even more preferably 3,000 or more, preferably 1,000,000 or less, more preferably 500,000 or less, and even more preferably 100,000 or less.

[0045] The glass transition temperature of the polyester resin (A2) is preferably -80°C or higher, more preferably -50°C or higher, even more preferably -20°C or higher, preferably 140°C or lower, more preferably 120°C or lower, and even more preferably 100°C or lower. When the glass transition temperature of the polyester resin (A2) is within the above range, the mobility of the polyester resin (A2) is good, and the effects of the present invention can be easily achieved.

[0046] The glass transition temperature of the polyester resin (A2) can be measured using a differential scanning calorimeter (DSC).

[0047] In the composite resin (A), the content of the vinyl polymer (A1) and the polyester resin (A2) is preferably 0.001 or more, more preferably 0.005 or more, even more preferably 0.01 or more, even more preferably 0.05 or more, and even more preferably 0.1 or more, preferably 3 or less, more preferably 2 or less, and even more preferably 1 or less. The amount of the vinyl polymer (A1) is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, even more preferably 1 part by mass or more, preferably 100 parts by mass or less, more preferably 10 parts by mass or less, and even more preferably 3 parts by mass or less.

[0048] The total content of the vinyl polymer (A1) and polyester resin (A2) in the composite resin (A) is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more, with an upper limit of 100% by mass.

[0049] The gel fraction of the composite resin (A) is preferably 0.01% by mass or more, more preferably 1% by mass or more, even more preferably 3% by mass or more, and even more preferably 10% by mass or more, with an upper limit of 100% by mass, and may be, for example, 90% by mass or less, and even more preferably 80% by mass or less.

[0050] The gel fraction of the composite resin (A) can be measured, for example, by the following method. First, the aqueous resin composition of the present invention is coated onto a glass plate so that the film thickness after drying is 0.5 mm, dried at 80°C for 2 hours, peeled off the glass plate, and dried further at 140°C for 5 minutes. The resulting sample is cut into a circle with a diameter of 29 mm. The weight of the sample before solvent immersion is measured and designated as G1. Next, the sample is immersed in toluene at room temperature for 24 hours, and the solvent-insoluble portion of the sample is separated by filtration through an 80-mesh wire mesh. After drying at 110°C for 1 hour, the weight is measured and designated as G2. The value obtained based on the following formula is taken as the gel fraction. Gel fraction (mass %) = (G2 / G1) × 100

[0051] In the composite resin (A), it is preferable that at least a portion of the surface of the vinyl polymer (A1) is coated with the polyester resin (A2), and it is preferable that a layer of the polyester resin (A2) is formed on the surface of the vinyl polymer (A1). The vinyl polymer (A1) is generally highly hydrophobic and difficult to disperse in water as is, but the coating of at least a portion of the surface of the vinyl polymer (A1) by the polyester resin (A2) improves its dispersibility in an aqueous medium. The vinyl polymer (A1) and the polyester resin (A2) may or may not be chemically bonded.

[0052] The composite resin can be produced by polymerizing a vinyl monomer (a) in an aqueous medium (B), described later, in the presence of the polyester resin (A2). Since the vinyl monomer (a) is hydrophobic, by coexisting with the polyester resin (A2) in the aqueous medium (B), at least a portion of the vinyl monomer (a) is incorporated into the polyester resin (B2), and by carrying out the polymerization reaction in this state, the composite resin (A) of the present invention can be produced.

[0053] More specifically, it is preferable that the polyester resin (A2) is subjected to polymerization of the vinyl monomer (a) in a dispersed state (pre-dispersion) in an aqueous medium (B). The pre-dispersion in which the polyester resin (A2) is dispersed in the aqueous medium (B) can be produced, for example, by reacting the polyol (b1) and the polycarboxylic acid (b2) under solvent-free conditions or in the presence of an organic solvent. From the viewpoint of safety and reducing the burden on the environment, some or all of the organic solvent may be removed by vacuum distillation or the like during or after the production of the polyester resin (A2).

[0054] During the polymerization reaction, if necessary, the additive (C) described later may be present, or the additive (C) may be added after the polymerization reaction.

[0055] When polymerizing the vinyl monomer (a), it is preferable to include a radical polymerization initiator. The polymerization initiator can be a photopolymerization initiator or a thermal polymerization initiator. Examples of photopolymerization initiators include benzophenone, benzyl, Michler ketone, thioxanthone, anthraquinone, benzoin, dialkoxyacetophenone, acyloxime ester, benzyl ketal, hydroxyalkylphenone, and halogenoketone. The photopolymerization initiator may be used in combination with a tertiary amine such as methylamine, diethanolamine, N-methyldiethanolamine, or tributylamine, as needed. Examples of thermal polymerization initiators include azo compounds such as 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2-methylbutyronitrile), 2,2'-azobis(2-methylpropionamidine) dihydrochloride, 4,4'-azobis(4-cyano)valeric acid, and 2,2'-azobis(2-amidinopropane) dihydrochloride; benzoyl peroxide, tert-butyl hydroperoxide, tert-butyl peroxypivalate, tert-butyl peroxybenzoate, tert-butyl peroxy-2-ethylhexanoate, and di-tert-butyl peroxy Organic peroxides such as oxide, di-tert-butyl hydroperoxide, cumene hydroperoxide, benzoyl peroxide, lauroyl peroxide, decanoyl peroxide, tert-butylcumyl peroxide, dicumyl peroxide, tert-butyl peroxylaurate, tert-butyl peroxybenzoate, cumene hydroperoxide, and paramenthane hydroperoxide; and thermal polymerization initiators such as inorganic peroxides such as hydrogen peroxide, ammonium persulfate, potassium persulfate, and sodium persulfate can be used.

[0056] The amount of the radical polymerization initiator is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, even more preferably 0.5 parts by mass or more, preferably 20 parts by mass or less, more preferably 10 parts by mass or less, and even more preferably 5 parts by mass or less, based on 100 parts by mass of the total vinyl compound.

[0057] The composite resin (A) is preferably dispersed in an aqueous medium (B). The dispersion state of the composite resin (A) can be confirmed, for example, by the presence or absence of precipitate in the aqueous resin composition.

[0058] The content of the composite resin (A) in the aqueous resin composition is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, preferably 70% by mass or less, more preferably 60% by mass or less, and even more preferably 50% by mass or less.

[0059] Examples of the aqueous medium (B) include water, organic solvents miscible with water, and mixtures thereof. Examples of organic solvents miscible with water include one or more types, such as alcohol solvents like methanol, ethanol, n-propanol, isopropyl alcohol, 1,2-propylene glycol, and 1,3-butylene glycol; ketone solvents like acetone and methyl ethyl ketone; glycol ether solvents like ethylene glycol-n-butyl ether, diethylene glycol-n-butyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol dimethyl ether, propylene glycol methyl ether, dipropylene glycol methyl ether, dipropylene glycol dimethyl ether, dipropylene glycol-n-butyl ether, and tripropylene glycol methyl ether; lactam solvents like N-methyl-2-pyrrolidone and N-ethyl-2-pyrrolidone; and amide solvents like N,N-dimethylformamide. Alcohol solvents are preferred.

[0060] Considering safety and reducing the burden on the environment, the aqueous medium (B) is preferably water only, or a mixture of water and an organic solvent that is miscible with water, and more preferably water only. The water content is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more, of 100% by mass of the aqueous medium (B).

[0061] The content of the aqueous medium (B) is preferably 30% to 80% by mass, and more preferably 50% to 70% by mass, of 100% by mass of the total amount of the aqueous resin composition.

[0062] The aqueous resin composition of the present invention may further contain various additives (C) such as crosslinking agents, surfactants, plasticizers, antistatic agents, waxes, light stabilizers, flow regulators, dyes, leveling agents, rheology control agents, ultraviolet absorbers, antioxidants, photocatalytic compounds, inorganic pigments, organic pigments, extender pigments, curing agents, curing catalysts, emulsifiers, and dispersion stabilizers.

[0063] The content of the additive (C) is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, and even more preferably 1 part by mass or less, per 100 parts by mass of the composite resin (A).

[0064] The aqueous resin composition of the present invention is initially homogeneous, but ultimately forms a coating film with a hydrophobic surface, and is suitable for paper coating and impregnation, textiles and nonwoven fabrics, carpets, civil engineering and construction materials, mortar cement, automobile parts, tire cords, paints, pastes, rust-preventive coatings, adhesives, plastic modifications, cosmetic puffs, electronic materials, general adhesives, coating and impregnation (nonwoven fabrics and paper), fiber impregnation and reinforcing fiber processing (carpets, etc.), moisture-proof and water-resistant coatings, cement and mortar, building material processing and wood bonding, synthetic leather, artificial leather, gloves, contraceptives, ink acceptors, ink dispersants, and the like. [Examples]

[0065] The present invention will be described in more detail below with reference to examples, but the present invention is not limited by the following examples, and it is certainly possible to implement it with appropriate modifications within the scope that is consistent with the spirit of the preceding and following descriptions, and all such modifications are included within the technical scope of the present invention.

[0066] (Synthesis Example 1: Synthesis of aqueous polyester resin composition (1)) In a reaction vessel equipped with a thermometer, nitrogen gas inlet tube, and stirrer, 17.1 parts by mass of isophthalic acid, 33.7 parts by mass of terephthalic acid, 18.1 parts by mass of diethylene glycol, 22.8 parts by mass of ethylene glycol, 6.5 parts by mass of dimethyl sodium 5-sulfoisophthalate, 1.9 parts by mass of trimellitic anhydride, and 0.02 parts by mass of tetraisopropyl titanate were charged while introducing nitrogen gas. A polycondensation reaction was carried out at 180-230°C for 12 hours until the acid value was 10 mg KOH / g or less, yielding polyester resin (A2-1). Next, 100 parts by mass of polyester resin (A2-1) was dissolved in 0.5 parts by mass of aqueous ammonia and 290 parts by mass of deionized water at 80°C while stirring to prepare an aqueous polyester resin composition (1) with a non-volatile content of 25.0% by mass. (Acid value: 12.3 mg KOH / g, Aromatic ring content: 3.8 mol / kg)

[0067] (Synthesis Example 2: Synthesis of aqueous polyester resin composition (2)) In a reaction vessel equipped with a thermometer, nitrogen gas inlet tube, and stirrer, 21.9 parts by mass of isophthalic acid, 39.2 parts by mass of terephthalic acid, 16.7 parts by mass of diethylene glycol, 14.7 parts by mass of ethylene glycol, 7.6 parts by mass of dimethyl sodium 5-sulfoizophthalate, and 0.02 parts by mass of tetraisopropyl titanate were charged while introducing nitrogen gas. A polycondensation reaction was carried out at 180-230°C for 12 hours until the acid value became 3 mg KOH / g or less, yielding polyester resin (A2-2). Next, 100 parts by mass of polyester resin (A2-2) was dissolved in 0.4 parts by mass of aqueous ammonia and 290 parts by mass of deionized water at 80°C while stirring to prepare an aqueous polyester resin composition (2) with a non-volatile content of 25.0% by mass. (Acid value: 6.7 mg KOH / g, Aromatic ring content: 4.5 mol / kg)

[0068] (Synthesis Example 3: Synthesis of aqueous polyester resin composition (3)) In a reaction vessel equipped with a thermometer, nitrogen gas inlet tube, and stirrer, 23 parts by mass of isophthalic acid, 39.2 parts by mass of terephthalic acid, 16 parts by mass of ethylene glycol, 16.9 parts of neopentyl glycol, and 0.1 parts by mass of tetraisopropyl titanate were charged while introducing nitrogen gas. A polycondensation reaction was carried out at 180-230°C for 5 hours until the acid value was 3 mg KOH / g or less. Next, 4.9 parts of trimellitic anhydride were added and stirred for 3 hours to carry out a polymerization reaction to obtain polyester resin (A2-3). Then, 100 parts by mass of polyester resin (A2-3) was dissolved in 200 parts by mass of methyl ethyl ketone while stirring at 60°C, and 3 parts by mass of triethylamine were added, followed by the slow addition of 367 parts by mass of ion-exchanged water to solubilize it in water. Next, under reduced pressure at 30-50°C, the methyl ethyl ketone was removed to prepare an aqueous polyester resin composition (3) with a non-volatile content of 25.0% by mass. (Acid value: 16.2mgKOH / g Aromatic ring amount: 4.6mol / kg)

[0069] (Synthesis Example 4: Synthesis of Synthetic Rubber Latex Resin (1)) Using 1 part of Newcol 261A [manufactured by Nippon Emulsifier Co., Ltd.] as an emulsifier and 200 parts by mass of ion-exchanged water, 79 parts by mass of butadiene, 19 parts by mass of styrene, and 2 parts by mass of acrylic acid were reacted with 0.5 parts by mass of ammonium persulfate (APS) under conditions of monomer-to-monomer emulsion polymerization (reaction temperature 60°C). Next, the mixture was concentrated to remove unreacted monomers, and a synthetic rubber latex (1) with a solid content of 45% by mass containing a vinyl polymer (A1-1) was obtained.

[0070] (Example 1: Synthesis of latex composite polyester resin (1)) 308.9 parts by mass of the aqueous polyester resin composition (1) obtained in Synthesis Example 1 was mixed with 137 parts by mass of deionized water, and 33.1 parts by mass of isoprene was reacted with 0.3 parts by mass of ammonia persulfate (APS) under conditions of monomer-to-monomer emulsion polymerization (reaction temperature 70°C). Then, the mixture was concentrated to remove unreacted monomers, and after adjusting the water content, a latex composite polyester resin (1) with a solid content of 30% by mass was obtained.

[0071] (Example 2: Synthesis of latex composite polyester resin (2)) In Synthesis Example 2, 223.8 parts by mass of aqueous polyester resin composition (2) was added to 187 parts by mass of deionized water. 53.7 parts by mass of isoprene and 13.4 parts by mass of methyl methacrylate were reacted with 0.5 parts by mass of ammonia persulfate (APS) under conditions of monomer-to-monomer emulsion polymerization (reaction temperature 70°C). The mixture was then concentrated to remove unreacted monomers, and after adjusting the water content, a latex-composite polyester resin (2) with a solid content of 35% by mass was obtained.

[0072] (Example 3: Synthesis of latex composite polyester resin (3)) 308.9 parts by mass of the aqueous polyester resin composition (3) obtained in Synthesis Example 3 was mixed with 137 parts by mass of deionized water, and 33.1 parts by mass of butadiene was reacted with 0.3 parts by mass of ammonia persulfate (APS) under conditions of monomer-to-monomer emulsion polymerization (reaction temperature 70°C). Then, concentration was performed to remove unreacted monomers, and after adjusting the water content, a latex composite polyester resin (3) with a solid content of 30% by mass was obtained.

[0073] (Example 4: Synthesis of latex composite polyester resin (4)) 313.5 parts by mass of the aqueous polyester resin composition (2) obtained in Synthesis Example 2 was mixed with 125 parts by mass of deionized water, and 28.2 parts by mass of butadiene and 12.1 parts by mass of glycidyl methacrylate were reacted with 0.3 parts by mass of ammonium persulfate (APS) under conditions of monomer-to-monomer emulsion polymerization (reaction temperature 70°C). Then, the mixture was concentrated to remove unreacted monomers, and after adjusting the water content, a latex composite polyester resin (4) with a solid content of 35% by mass was obtained.

[0074] (Example 5: Synthesis of latex composite polyester resin (5)) 313.5 parts by mass of the aqueous polyester resin composition (2) obtained in Synthesis Example 2 was mixed with 124.9 parts by mass of deionized water, and 12.1 parts by mass of isoprene and 28.2 parts by mass of methyl methacrylate were reacted with 0.3 parts by mass of ammonia persulfate (APS) under conditions of monomer-to-monomer emulsion polymerization (reaction temperature 70°C). Then, the mixture was concentrated to remove unreacted monomers, and after adjusting the water content, a latex composite polyester resin (5) with a solid content of 45% by mass was obtained.

[0075] (Comparative Example 1) The aqueous polyester resin composition (2) obtained in Synthesis Example 2 was used.

[0076] (Comparative Example 2: Blend of water-based polyester resin and synthetic rubber latex resin (7)) 100 parts by mass of the aqueous polyester resin composition (2) obtained in Synthesis Example 2 was added to 66.7 parts by mass of the synthetic rubber latex resin (4) from Synthesis Example 4, and the mixture was stirred for a certain period of time to obtain a blend with a solid content of 37.0% by mass.

[0077] (Comparative Example 3) The synthetic rubber latex resin (4) obtained in Synthesis Example 4 was used.

[0078] The following measurements were performed on each of the obtained aqueous resin compositions.

[0079] [Method for evaluating adhesion between different substrates] An aqueous resin composition was coated onto a polyethylene terephthalate (PET) substrate and dried at 100°C for 20 seconds. An ABS substrate or a polyvinyl chloride (PVC) substrate was then attached to the coated surface and heat-treated again at 100°C for 3 minutes. After that, the PET and the ABS or PVC substrate were peeled off, and the condition of the peeled substrates was observed. ○: The PET, SBR, or PVC substrate underwent material failure, or it did not peel off. △: Adhesion was confirmed between PET and SBR / PVC substrates, but the adhesive layer remained on only one of the substrates, either the PET or the SBR / PVC substrate. ×: Almost no adhesion was observed between PET and SBR / PVC substrates, and an adhesive layer remained only on either the PET or SBR / PVC substrate.

[0080] [Method for measuring film properties] A coating film (thickness 150 μm) was prepared on a polypropylene (PP) film substrate, dried, and a tensile test was performed using the resulting dried coating film. The film was stretched at a tensile speed of 300 mm / min, and the elongation ratio relative to its length at break and its strength were measured.

[0081] [Method for evaluating solvent resistance] A coating film (thickness 150 μm) was prepared on a PP substrate, dried, and peeled off. The resulting dried coating film was then subjected to a durability test against methyl ethyl ketone (MEK). Specifically, the obtained dried coating film was immersed in methyl ethyl ketone at room temperature for one day. The amount of elution was calculated by subtracting the weight after immersion from the weight before immersion, and this was divided by the weight of the coating film before immersion to obtain the elution rate.

[0082] [Methods for evaluating water resistance and water swelling] A coating film (thickness 150 μm) was prepared on a PP substrate, dried, and peeled off. The resulting dried coating film was then subjected to a water durability test. Specifically, the obtained dried coating film was immersed in water at room temperature for one day. The amount of elution was calculated by subtracting the weight after immersion from the weight before immersion. This amount of elution was divided by the weight of the dried coating film before immersion to obtain the elution rate. Furthermore, the area of ​​the dried coating film before immersion was subtracted from the area of ​​the dried coating film after immersion to obtain the swelling area, and this swelling area was divided by the area of ​​the dried coating film before immersion to obtain the swelling rate.

[0083] The evaluation results are shown in Table 1.

[0084] [Table 1]

[0085] Examples 1 to 5 are embodiments of the present invention, and it was possible to form a coating film that was initially homogeneous but, upon heating, caused the resin to segregate, ultimately exhibiting adhesion between different types of substrates.

[0086] Comparative Example 1 was an example that did not include the vinyl polymer (A1), and the adhesion between dissimilar substrates was poor. Comparative Example 2 was an example in which the vinyl polymer (A1) and polyester resin (A2) were not compounded, and in particular, the adhesion between PET and PVC was not sufficiently satisfactory. Comparative Example 3 was an example that did not include the polyester resin (A2), and the adhesion between dissimilar substrates was poor.

Claims

1. A laminate having a coating film formed from an aqueous resin composition containing a composite resin (A) and an aqueous medium (B), The composite resin (A) comprises a vinyl polymer (A1) and a polyester resin (A2). The vinyl polymer (A1) has units derived from a vinyl monomer (a) which contains at least one conjugated diene compound (a1) selected from the group consisting of 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 1,3-hexadiene, 1,3-heptadiene, 2,3-dimethylbutadiene, 2-phenyl-1,3-butadiene, 3-methyl-1,3-pentadiene, and 2-chlor-1,3-butadiene. The acid value of the polyester resin (A2) is 0.1 mg KOH / g or more and 100 mg KOH / g or less. A laminate characterized in that the mass ratio ((A1) / (A2)) of the vinyl polymer (A1) to the polyester resin (A2) is 0.001 or more and 3 or less.

2. The laminate according to claim 1, wherein the amount of aromatic rings contained in the polyester resin (A2) is 0.01 mol / kg or more and 20 mol / kg or less.

3. The laminate according to claim 1, wherein the composite resin (A) is such that at least a portion of the surface of the vinyl polymer (A1) is coated with the polyester resin (A2).

Images