Water-based barrier composition, laminate

Abstract

To provide a water-based composition for barrier having superior barrier properties, and a laminated material.SOLUTION: A water-based composition for barrier contains a urethane resin (A) comprising a polyol (a1), a polyisocyanate (a2) and a chain extender (a3) as essential reaction components, and at least one wax (B) selected from the group consisting of a paraffin, carnauba wax and an alkyl ketene dimer. The content ratio between the component (A) and the component (B) in non-volatile content weight is (A) / (B)=25 / 75 to 95 / 5.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an aqueous barrier composition and a laminate. [Background technology]

[0002] In applications such as packaging materials for food, pharmaceuticals, and the like, and electronic devices such as organic electroluminescence (EL) devices, barrier properties are required in terms of product quality. For example, in packaging applications, barrier properties are imparted by applying a barrier composition to a substrate and drying it to form a coating of the composition to prevent gases such as water vapor and oxygen, and liquids such as water and oil, from penetrating from the outside to the inside of the substrate or from leaking from the inside to the outside. Conventionally, known barrier compositions include polyvinyl alcohol and polyvinylidene chloride (Patent Document 1, etc.).

[0003] However, polyvinyl alcohol is easily affected by humidity and does not exhibit water vapor barrier properties, particularly under high temperature and humidity conditions. Furthermore, when polyvinylidene chloride is used, harmful gases are generated when it is incinerated, which is undesirable from an environmental standpoint.

[0004] Another known technology is a multilayer resin sheet in which water vapor barrier resin layers made of olefin resin are laminated on both sides of an oxygen barrier resin layer via adhesive layers (Patent Document 2). However, this technology also has the problem of using a large amount of petroleum-derived plastics.

[0005] One way to reduce the amount of petroleum-based plastics used is to apply a small amount of diluted barrier composition to the substrate. In addition, water-based barrier compositions are now preferred due to the need to reduce VOC emissions. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 8-134242 [Patent Document 2] International Publication No. 2017 / 221374 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide an aqueous barrier composition and a laminate that exhibit barrier properties. [Means for solving the problem]

[0008] As a result of extensive investigations, the present inventors have found that an aqueous barrier composition containing a specific urethane resin and a specific wax can solve the above-mentioned problems, and have thus completed the present invention. That is, the present invention relates to the following aqueous barrier composition and laminate.

[0009] 1. A polyurethane resin (A) containing, as essential reaction components, a polyol (a1), a polyisocyanate (a2), and a chain extender (a3), and one or more waxes (B) selected from the group consisting of paraffin, carnauba wax, and alkyl ketene dimer; An aqueous barrier composition in which the content ratio of the component (A) and the component (B) in terms of nonvolatile content by weight is (A) / (B)=25 / 75 to 95 / 5.

[0010] 2. The aqueous barrier composition according to the above item 1, wherein the component (a1) contains a polyether polyol.

[0011] 3. The aqueous barrier composition according to the above item 1 or 2, wherein the component (a3) ​​contains a dialkanolalkanoic acid.

[0012] 4. The aqueous barrier composition according to any one of items 1 to 3 above, wherein the reaction components further comprise a (meth)acrylic acid hydroxyalkyl ester (a4).

[0013] 5. The aqueous barrier composition according to any one of items 1 to 4 above, wherein the reaction components further comprise a (meth)acrylic acid alkyl ester (a5) having no hydroxy group.

[0014] 6. The aqueous barrier composition according to any one of items 1 to 5 above, further comprising a rosin resin and / or a curing agent.

[0015] 7. A laminate having a coating of the aqueous barrier composition according to any one of items 1 to 6 on at least one surface of a substrate. [Effects of the Invention]

[0016] The aqueous barrier composition of the present invention exhibits excellent barrier properties. DETAILED DESCRIPTION OF THE INVENTION

[0017] The aqueous barrier composition of the present invention contains a specific urethane resin (A) (hereinafter referred to as component (A)) and a wax (B) (hereinafter referred to as component (B)).

[0018] In the present invention, the term "barrier" refers to a barrier against water vapor, oxygen, water, oil, etc., and applications requiring such a "barrier" include, for example, packaging materials and containers for foods, medicines, miscellaneous goods, etc., building materials, precision instruments, electronic devices, industrial materials, etc.

[0019] Component (A) is a urethane resin, and its essential reaction components are polyol (a1) (hereinafter referred to as component (a1)), polyisocyanate (a2) (hereinafter referred to as component (a2)), and chain extender (a3) ​​(hereinafter referred to as component (a3)).

[0020] The component (a1) is a compound having two or more hydroxy groups in the molecule, and examples thereof include low molecular weight glycols such as ethylene glycol, diethylene glycol, 1,2-propylene glycol, and 1,4-butanediol, polyether polyols, poly(meth)acrylic polyols, polyester polyols, and polycarbonate polyols. These may be used alone or in combination of two or more. Among these, polyether polyols are preferred.

[0021] Examples of polyether polyols include polyethylene glycol, polypropylene glycol, polybutylene glycol, polytetramethylene glycol, polyhexamethylene glycol, polyheptamethylene glycol, polydecamethylene glycol, polyoxyethylene-polyoxypropylene glycol, polyoxytetramethylene-polyoxyethylene glycol, polyoxytetramethylene-polyoxypropylene glycol, etc. Polyether polyols with a random structure or a block structure can be used.

[0022] Commercially available polyether polyols include "ADEKA Polyether P-400," "ADEKA Polyether G-400," "ADEKA Polyether T-400," "ADEKA Polyether AM-302," "ADEKA Polyether P1000," and "ADEKA Polyether P2000" (all manufactured by ADEKA Corporation); "Polyethylene Glycol #1,540" (manufactured by Nacalai Tesque, Inc.); "Polypropylene Glycol 400" (manufactured by Junsei Chemical Co., Ltd.); "PEG #200," "PEG #300," "PEG #400," "PEG #600," "PEG #1000," "PEG #1500," and "PEG #2 000," "PEG#4000," "Uniol D-200," "Uniol D-700," "Uniol D-1000," "Uniol D-1200," "Uniol D-2000," "Uniol D-4000," "Uniol PB-500," "Uniol PB-700," "Uniol PB-1000," "Uniol PB-2000," "Polycerin DC-1100," "Polycerin DC-1800E," "Polycerin DC-3000E," "Polycerin DCB-1000," "Polycerin DCB-2000," and "Polycerin DCB-4000" (all manufactured by NOF Corporation).

[0023] Examples of the component (a2) include aliphatic diisocyanates such as methylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, and dimer diisocyanate in which the carboxyl group of a dimer acid is substituted with an isocyanate group; Alicyclic diisocyanates such as cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-di(isocyanatomethyl)cyclohexane, and methylcyclohexane diisocyanate; Aromatic diisocyanates such as 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-diphenyltetramethylmethane diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, m-tetramethylxylylene diisocyanate, 1,5-naphthylene diisocyanate, 4,4'-dibenzyl isocyanate, and 1,3-phenylene diisocyanate; Examples of the diisocyanates include amino acid diisocyanates such as lysine diisocyanate. These may be used alone or in combination of two or more. Furthermore, as the component (a2), nurates, adducts, or biuret forms of these may also be used.

[0024] The ratio of the (a1) component to the (a2) component is usually determined by the number of moles of isocyanate groups in the (a2) component (NCO (a2) ) and the number of moles of hydroxyl groups in the (a1) component (OH (a1) ) and the ratio (NCO (a2) / OH (a1) ) and it is preferable to set it to about 1.1 / 1 to 8 / 1.

[0025] Component (a3) ​​is a chain extender.

[0026] Examples of the component (a3) ​​include diamines such as ethylenediamine, propylenediamine, hexamethylenediamine, isophoronediamine, dimer diamine, dicyclohexylmethane-4,4'-diamine, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine, 2-hydroxypropylethylenediamine, and di-2-hydroxypropylethylenediamine; Triamines such as diethylenetriamine, dipropylenetriamine, and dibutylenetriamine; tetramines such as triethylenetetramine and tripropylenetetramine; N-alkyldialkanolamines such as N-methyldiethanolamine, N-ethyldiethanolamine, N-propyldiethanolamine, N-isopropyldiethanolamine, N-butyldiethanolamine, N-isobutyldiethanolamine, N-oleyldiethanolamine, N-stearyldiethanolamine, N-methyldiisopropanolamine, N-ethyldiisopropanolamine, N-propyldiisopropanolamine, and N-butyldiisopropanolamine; Hydrazine or its hydrazine derivatives (such as adipic acid hydrazide); Dialkanolalkanoic acids such as glyceric acid, dioxymaleic acid, dioxyfumaric acid, dimethylolacetic acid, dimethylolpropionic acid, dimethylolbutanoic acid, dimethylolpentanoic acid, and dimethylolhexanoic acid; Examples of the aromatic hydroxycarboxylic acids include 4,4-di(hydroxyphenyl)butanoic acid, 4,4-di(hydroxyphenyl)pentanoic acid, and 2,6-dioxybenzoic acid. These may be used alone or in combination of two or more. Among these, dialkanolalkanoic acids are preferred because they make the resulting component (A) more soluble or dispersible in water.

[0027] The dialkanolamine may be used in the form of a quaternized salt. The quaternized salt refers to a product obtained by reacting the dialkanolamine with a quaternizing agent, and examples of the quaternizing agent include inorganic acids such as hydrochloric acid, sulfuric acid, and phosphoric acid; organic acids such as dimethyl sulfate, acetic acid, and propionic acid; and organic halogens such as methyl chloride, benzyl chloride, and epichlorohydrin.

[0028] The carboxyl groups of the dialkanolalkanoic acids and aromatic hydroxycarboxylic acids may be neutralized with a neutralizing agent.

[0029] Examples of the neutralizing agent include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, ammonia, and organic amines such as trimethylamine, triethylamine, triethanolamine, triisopropanolamine, N,N-dimethylethanolamine, and N,N-diethylethanolamine. These may be used alone or in combination of two or more.

[0030] The amount of component (a3) ​​used is usually 1 to 30% by weight, and preferably 3 to 20% by weight, based on 100% by weight of the reactive components that make up component (A).

[0031] The component (A) of the present invention may further contain a (meth)acrylic acid hydroxyalkyl ester (a4) (hereinafter referred to as component (a4)) as a reaction component.

[0032] Examples of component (a4) include 2-hydroxyethyl (meth)acrylate, 2-hydroxy n-propyl (meth)acrylate, 3-hydroxy n-propyl (meth)acrylate, 3-hydroxy n-butyl (meth)acrylate, 4-hydroxy n-butyl (meth)acrylate, and 6-hydroxy n-hexyl (meth)acrylate. These may be used alone or in combination of two or more. Among these, those having a hydroxyalkyl group having 2 to 3 carbon atoms are preferred from the viewpoint of excellent reactivity, and 2-hydroxyethyl (meth)acrylate and 2-hydroxy n-propyl (meth)acrylate are more preferred.

[0033] The amount of component (a4) used is usually 10% by weight or less, and preferably 0.1 to 5% by weight, based on 100% by weight of the reactive components that make up component (A).

[0034] The component (A) of the present invention may further contain a (meth)acrylic acid alkyl ester (a5) (hereinafter referred to as component (a5)) that does not have a hydroxyl group as a reaction component.

[0035] Examples of component (a5) include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, n-pentyl (meth)acrylate, cyclopentyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, n-decyl (meth)acrylate, isobornyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, myristyl (meth)acrylate, isomyristyl (meth)acrylate, palmityl (meth)acrylate, stearyl (meth)acrylate, and isostearyl (meth)acrylate. These may be used alone or in combination of two or more. Among these, from the viewpoint of enhancing the barrier property, those having an alkyl group having 12 to 18 carbon atoms are preferred, and lauryl (meth)acrylate, myristyl (meth)acrylate, palmityl (meth)acrylate, and stearyl (meth)acrylate are more preferred.

[0036] The amount of component (a5) used is usually 50% by weight or less, and preferably 10 to 40% by weight, based on 100% by weight of the reactive components that make up component (A).

[0037] The reaction components may further contain a chain terminator (a6) (hereinafter referred to as component (a6)). Examples of component (a6) include monoalcohols such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, and isobutyl alcohol; monoamines such as ethylamine, n-propylamine, diethylamine, di-n-propylamine, and di-n-butylamine; and alkanol monoamines such as monoethanolamine and diethanolamine. These may be used alone or in combination of two or more.

[0038] The amount of component (a6) used is usually 5% by weight or less, and preferably 3% by weight or less, based on 100% by weight of the reactive components that make up component (A).

[0039] The (A) component can be obtained, for example, by reacting the (a1) component with the (a2) component to produce a urethane prepolymer, and then reacting the urethane prepolymer with the (a3) ​​component and, if necessary, with the (a4) to (a6) components.

[0040] As for reaction conditions for the step of obtaining a urethane prepolymer, the temperature is usually about 40 to 150° C., and preferably about 60 to 100° C. The reaction time is usually about 1 to 20 hours, and preferably about 1 to 10 hours. Next, the urethane prepolymer is reacted with component (a3), and optionally components (a4) to (a6), under conditions such as a temperature of typically about 20 to 100°C, and preferably about 30 to 80°C, and a time of typically about 1 to 10 hours, and preferably about 1 to 5 hours. The method and order of mixing the components are not particularly limited.

[0041] The production of the component (A) may be carried out in the absence of a solvent or in the presence of a solvent.

[0042] Examples of the solvent include aromatic hydrocarbons such as benzene, toluene, ethylbenzene, n-propylbenzene, t-butylbenzene, o-xylene, m-xylene, p-xylene, tetralin, decalin, and aromatic naphtha; aliphatic hydrocarbons such as n-hexane, n-heptane, n-octane, isooctane, and n-decane; alicyclic hydrocarbons such as cyclohexane; esters such as ethyl acetate, n-butyl acetate, n-amyl acetate, 2-hydroxyethyl acetate, 2-butoxyethyl acetate, 3-methoxybutyl acetate, and methyl benzoate; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, isophorone, cyclohexanone, and methylcyclohexanone; Examples of suitable solvents include glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether; alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, s-butanol, and t-butanol; amides such as N,N-dimethylformamide and N,N-dimethylacetamide; amines such as N-methylpyrrolidone; water such as ion-exchanged water, purified water, tap water, soft water, hard water, and industrial water; and dimethyl sulfoxide. These may be used alone or in combination of two or more. After the reaction is complete, the solvent may be removed by distillation under reduced pressure or the like.

[0043] The amount of solvent used is preferably adjusted so that the reaction concentration is 10% by weight or more.

[0044] In the above reaction, the component (B) described below may be added.

[0045] Component (A) may further contain pigments, water retention agents, antifoaming agents, preservatives, leveling agents, colorants, antiblocking agents, antioxidants, UV absorbers, thickeners, dispersants, fillers, and the like.

[0046] The weight-average molecular weight of the obtained component (A) is 5000 to 2000000. The weight-average molecular weight is a value measured by gel permeation chromatography (GPC) using polystyrene as a standard substance.

[0047] Furthermore, the viscosity of a solution of component (A) with a nonvolatile content of 35% by weight at 25°C is typically 5 to 20,000 mPa·s, and preferably 10 to 10,000 mPa·s. Here, "viscosity" refers to a value measured with a B-type viscometer.

[0048] Component (B) is one or more waxes selected from the group consisting of paraffin, carnauba wax, and alkyl ketene dimer, and is a component that imparts barrier properties. Note that alkyl ketene dimer is abbreviated as "AKD." In the following, the wax of component (B) may also be referred to as paraffin wax, carnauba wax, or AKD wax.

[0049] Paraffin is obtained by vacuum distilling crude oil, and separating and refining highly crystalline hydrocarbons from the resulting distillate, and is composed primarily of straight-chain hydrocarbons (normal paraffins).

[0050] Regarding the physical properties of paraffin, for example, the melting point is preferably 45 to 80°C, and more preferably 55 to 80°C.

[0051] In the present invention, it is preferable to use paraffin in an aqueous emulsion prepared by using a dispersant, such as a nonionic surfactant, cationic surfactant, or anionic surfactant as described in JP-A-2013-237941.

[0052] Commercially available solid and / or liquid products include, for example, "Paraffin 115," "Paraffin 120," "Paraffin 125," "Paraffin 130," "Paraffin 135," "Paraffin 140," "Paraffin 145," "Paraffin 150," "Paraffin 155," and "HNP-51" (all manufactured by Nippon Seiro Co., Ltd.). Examples of aqueous emulsions include "Sizepine W-116H" (manufactured by Arakawa Chemical Industries, Ltd.). These may be used alone or in combination of two or more.

[0053] Carnauba wax is extracted from palm trees of the palm family, and the wax produced is called carnauba wax.

[0054] Carnauba wax is a wax of natural origin, and contains wax ester as its main component, as well as free fatty acids, free alcohols, and hydrocarbons.

[0055] Regarding the physical properties of the carnauba wax, for example, the melting point is preferably 60 to 110° C., more preferably 80 to 90° C. The acid value is preferably 10 mg·KOH / g or less.

[0056] Commercially available carnauba waxes include, for example, "Cellosol 524" (manufactured by Chukyo Yushi Co., Ltd.), "EMUSTAR-0413" (manufactured by Nippon Seiro Co., Ltd.), "Carnauba Wax No. 1 Flakes," "Carnauba Wax No. 1 Powder," "Carnauba Wax No. 2 Flakes," "Carnauba Wax No. 2 Powder," "Carnauba Wax No. 3 Flakes," and "Carnauba Wax No. 3 Powder" (all manufactured by Toyochem Co., Ltd.).

[0057] AKD is, for example, a compound represented by the following general formula (1) (R 1 and R 2 and each represent an alkyl group or an alkenyl group, and may be the same or different.

[0058] [ka]

[0059] Examples of the alkyl group include a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tetradecyl group, a hexadecyl group, an octadecyl group, an eicosyl group, a docosyl group, a tetracosyl group, a hexacosyl group, an octacosyl group, a triacontyl group, and a dotriacontyl group, which may be branched.

[0060] Examples of alkenyl groups include butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tetradecenyl, hexadecenyl, octadecenyl, eicosenyl, docosenyl, tetracosenyl, hexacosenyl, octacosenyl, triacontenyl, and dotriacontenyl groups, which may be branched.

[0061] These AKDs may be used alone or in combination of two or more. Among them, in order to enhance the barrier property, R 1 and R 2 are preferably each represented by an alkyl group or an alkenyl group having 14 to 24 carbon atoms, and R 1 and R 2 are more preferably each represented by an alkyl group having 14 to 24 carbon atoms, i.e., a tetradecyl group (number of carbon atoms: 14), a hexadecyl group (number of carbon atoms: 16), an octadecyl group (number of carbon atoms: 18), an eicosyl group (number of carbon atoms: 20), a docosyl group (number of carbon atoms: 22), or a tetracosyl group (number of carbon atoms: 24).

[0062] In the present invention, it is preferable to use AKD prepared as an aqueous emulsion using a known emulsifier. Examples of emulsifiers used in producing the aqueous emulsion and their production methods include those described in JP-A-2-19592, JP-A-2-293493, and JP-A-2012-211422.

[0063] Other commercially available products include, for example, "Sizepine K-287," "Sizepine K-903-20," "Sizepine K-931," and "Sizepine K-924" (all manufactured by Arakawa Chemical Industries, Ltd.), "AD1602," "AD1606," "AD1608," "AD1612," "AD1614," "AD1638," "AD1640," "SE2360," and "SE2380" (all manufactured by Seiko PMC Corporation), the "KDG" series, and the "SAK" series (all manufactured by Toho Chemical Industry Co., Ltd.).

[0064] Component (B) may further contain pigments, water retention agents, antifoaming agents, preservatives, leveling agents, colorants, antiblocking agents, antioxidants, UV absorbers, thickeners, dispersants, fillers, and the like.

[0065] The content ratio of component (A) to component (B) in terms of nonvolatile weight is (A) / (B)=25 / 75 to 95 / 5. When the content ratio is within this range, the coating film of the aqueous barrier composition exhibits excellent barrier properties. From the same viewpoint, the content ratio is preferably (A) / (B)=30 / 70 to 90 / 10, and more preferably (A) / (B)=50 / 50 to 90 / 10.

[0066] The aqueous barrier composition of the present invention is obtained by mixing components (A) and (B), and, if necessary, water. Mixing conditions include a temperature of 10 to 90°C (preferably 20 to 80°C). There are no particular limitations on the order, method, or time of mixing the components.

[0067] The aqueous barrier composition of the present invention may further contain additives such as rosin-based resins (e.g., gum rosin, wood rosin, tall oil rosin, saponified rosin, hydrogenated rosin, fumarated rosin, maleated rosin, and rosin ester); non-rosin-based resins (e.g., acrylic resin, styrene-butadiene resin, polyester resin, modified polyolefin resin, petroleum resin, and polyvinyl alcohol); curing agents (e.g., carbodiimide curing agents, polyisocyanate curing agents, aziridine curing agents, and melamine curing agents); pigments, water retention agents, antifoaming agents, antioxidants, preservatives, leveling agents, colorants, oil-resistant agents, water-resistant agents, antiblocking agents, anti-slip agents, and heat-sealing agents). These additives may be used alone or in combination of two or more. Furthermore, the content of the additives is preferably 20 parts by weight or less, and more preferably 10 parts by weight or less, per 100 parts by weight of the total of components (A) and (B), so as not to impair the barrier properties.

[0068] As for the physical properties of the obtained aqueous barrier composition, the non-volatile content is usually 5 to 50% by weight, and preferably 10 to 40% by weight.

[0069] The viscosity of a solution of the aqueous barrier composition having a nonvolatile content of 30% by weight at a temperature of 25°C is usually 10 to 1000 mPa·s, and preferably 20 to 500 mPa·s.

[0070] The laminate of the present invention has a coating of the aqueous barrier composition on at least one surface of a substrate.

[0071] The laminate can be obtained, for example, by applying an aqueous barrier composition to at least one surface of a substrate and drying it.

[0072] The substrate may be, for example, paper Examples include:

[0073] Examples of base paper include those made on various papermaking machines using chemical pulps such as hardwood pulp (LBKP) and softwood pulp (NBKP); mechanical pulps such as groundwood pulp (GP), refiner ground pulp (RGP), and thermomechanical pulp (TMP); DIP, mercerized pulp, and recycled paper pulp. More specific examples include bleached kraft paper, unbleached kraft paper, fine paper, medium-quality paper, lightly coated paper, coated paper, processed base paper, paperboard, white paperboard, liner, semi-glassine paper, glassine paper, and parchment paper. The pulp may also contain pH adjusters such as aluminum sulfate, sulfuric acid, and sodium hydroxide; papermaking chemicals such as sizing agents, paper strength agents such as starch and polyacrylamide, and wet strength agents; and fillers such as talc, clay, kaolin, titanium dioxide, and calcium carbonate.

[0076] Also, Hara paper The sheet may further have an anchor layer, a filling layer, a water-resistant layer, an oil-resistant layer, an antistatic layer, etc., provided on one or both sides thereof.

[0077] Examples of methods for applying the aqueous barrier composition include a bar coater, knife coater, size press coater, roll coater, reverse roll coater, curtain coater, gravure coater, air knife coater, calendar, gate roll coater, blade coater, two-roll size press, rod metering, etc. The amount of the aqueous barrier composition to be applied (in terms of nonvolatile content) is not particularly limited, but is usually 0.1 to 10 g / m 2 Approximately, preferably 1 to 6 g / m 2 That's about it.

[0078] After coating, the substrate is dried by heat. Examples of heat sources include a hot air dryer, an infrared heater, a rotary dryer, etc. The drying conditions are, for example, a temperature of 80 to 220°C (preferably 100 to 200°C) and a time of 0.1 to 180 minutes (preferably 0.5 to 60 minutes).

[0079] The laminate obtained by the above-mentioned production method may have a heat seal layer, a water-resistant layer, an oil-resistant layer, etc. provided on the coating of the aqueous barrier composition. [Example]

[0080] The present invention will be described below with reference to examples, but the present invention is not limited thereto. In the examples and comparative examples, "parts" and "%" are by weight unless otherwise specified.

[0081] Manufacturing Example 1 A reaction vessel equipped with a stirrer, thermometer, condenser, and nitrogen gas inlet tube was charged with 38.1 parts of dimethylol butanoic acid, 314.5 parts of Polyserine DCB-2000 (polyoxytetramethylene-polyoxypropylene glycol, number average molecular weight 2000, manufactured by NOF Corporation), 128.9 parts of isophorone diisocyanate, 12.7 parts of 2-hydroxyethyl acrylate, and 256.1 parts of stearyl methacrylate. The reaction was carried out for 5 hours at 85 ° C. under a nitrogen stream to obtain 750.3 parts of urethane prepolymer. Next, the urethane prepolymer was added and dispersed under stirring in an aqueous solution consisting of 1208.0 parts of water, 225.0 parts of isopropyl alcohol, 26.6 parts of triethylamine, and 27.8 parts of adipic acid dihydrazide, and the mixture was reacted at 50 ° C. for 3 hours. Next, 5.0 parts of an azo polymerization initiator (product name: "V-601", manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added, and the mixture was allowed to react at 80°C for 3 hours. A predetermined amount of water was then added to obtain a urethane resin (A-1) with a nonvolatile content of 35%, a viscosity of 300 mPa·s, and a pH of 8.0.

[0082] Manufacturing Example 2 A reaction vessel equipped with a stirrer, thermometer, condenser, and nitrogen gas inlet tube was charged with 59.4 parts of dimethylolbutanoic acid, 489.9 parts of PTMG1000 (polytetramethylene glycol, number average molecular weight 1000, manufactured by Mitsubishi Chemical Corporation), 275.5 parts of isophorone diisocyanate, and 2.0 parts of 2-hydroxyethyl acrylate. The mixture was reacted at 85°C for 5 hours under a nitrogen stream to obtain 826.8 parts of urethane prepolymer. Next, the urethane prepolymer was added and dispersed in an aqueous solution consisting of 1340.0 parts of water, 225.0 parts of isopropyl alcohol, 40.5 parts of triethylamine, and 43.3 parts of adipic acid dihydrazide with stirring, and the mixture was reacted at 50°C for 3 hours. Next, 0.1 parts of an azo polymerization initiator (trade name: "V-50", manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was added, and the mixture was reacted at 80°C for 1 hour. A predetermined amount of water was further added to obtain a urethane resin (A-2) with a nonvolatile content of 35%, a viscosity of 600 mPa·s, and a pH of 8.0.

[0083] Manufacturing Example 3 A reaction vessel equipped with a stirrer, thermometer, condenser, and nitrogen gas inlet was charged with 59.4 parts of dimethylolbutanoic acid, 489.9 parts of Polyserine DCB-2000, and 200.8 parts of isophorone diisocyanate. The mixture was reacted for 5 hours at 85°C under a nitrogen stream to yield 750.1 parts of urethane prepolymer. The urethane prepolymer was then added to an aqueous solution of 1208 parts of water, 225 parts of isopropyl alcohol, 40.5 parts of triethylamine, and 43.3 parts of adipic acid dihydrazide with stirring. The mixture was reacted for 3 hours at 50°C, and a predetermined amount of water was added to yield urethane resin (A-3) with a nonvolatile content of 35%, a viscosity of 800 mPa·s, and a pH of 8.0.

[0084] Example 1 An aqueous barrier composition was obtained by mixing 142.9 parts (non-volatile content: 50 parts) of urethane resin (A-1), 166.7 parts (non-volatile content: 50 parts) of paraffin wax (product name: "Sizepine W-116H", manufactured by Arakawa Chemical Industries, Ltd., emulsion), and 23.7 parts of ion-exchanged water.

[0085] Examples 2 to 19, Comparative Examples 1 to 6 The same procedure as in Example 1 was carried out except that the compositions and contents were changed as shown in Table 1, to obtain aqueous barrier compositions.

[0086] (Preparation of laminate (1)) Commercially available kraft paper (basis weight 70 g / m 2 , Air permeability: 10 seconds, Moisture permeability: 10000g / m 2 After applying the aqueous barrier composition of each Example and Comparative Example with a wire bar for 24 hours or more, the coating was dried for 3 minutes in a hot air dryer at 120°C to obtain a laminate (1).

[0087] (moisture permeability) The measurement was performed in accordance with the moisture permeability test method (cup method) of JIS Z 0208. In an atmosphere of 40°C temperature and 90% humidity, the laminate (1) (cut into a circle with a diameter of 7 cm) was cut into a 1 m2 area. 2 The number of grams of water vapor passing through per 24 hours was measured.

[0088] [Table 1] *1: The weight parts of components (A) and (B) are expressed as non-volatile weight. *2: The weight parts of additives are expressed as the weight of non-volatile content relative to 100 parts by weight (non-volatile content) of the total of components (A) and (B). *3: The amount of coating is expressed as the non-volatile content.

[0089] The symbols shown in Table 1 represent the following compounds: (resin) A-1: Urethane resin of Manufacturing Example 1 A-2: Urethane resin of Manufacturing Example 2 A-3: Urethane resin of Manufacturing Example 3 C-1: Olefin resin (product name: "Polymaron 482S", manufactured by Arakawa Chemical Industries, Ltd., aqueous solution) (wax) B-1: Paraffin wax (product name: "Sizepine W-116H", manufactured by Arakawa Chemical Industries, Ltd., emulsion) B-2: Carnauba wax (product name: "EMUSTAR-0413", Nippon Seiro Co., Ltd., emulsion) B-3: AKD wax (product name: "Sizepine K-924", manufactured by Arakawa Chemical Industries, Ltd., emulsion) D-1: Polyethylene wax (product name: Chemipearl W401, manufactured by Mitsui Chemicals, Inc., emulsion) D-2: Fatty acid wax (product name: "Sizepine CA-956", manufactured by Arakawa Chemical Industries, Ltd., emulsion) (additives) E-1: Saponified rosin (product name: "Sizepine E", manufactured by Arakawa Chemical Industries, Ltd., aqueous solution) E-2: Rosin resin (product name: Sizepine N-817, manufactured by Arakawa Chemical Industries, Ltd., emulsion) E-3: Carbodiimide curing agent (trade name: "Carbodilite SV-02", manufactured by Nisshinbo Chemical Inc., aqueous solution)

[0090] (Preparation of laminate (2)) Commercially available processed base paper (basis weight 50 g / m 2 , Air permeability: 90 seconds, Moisture permeability: 10000g / m 2 After 24 hours or more, the aqueous barrier composition of Example 1 was applied with any wire bar, and then dried in a hot air dryer at 120°C for 3 minutes, with an application amount of 5 g / m 2 The moisture permeability was measured in the same manner as in the previous paragraph, and was found to be 30 g / m 2 -Excellent barrier properties were demonstrated for 24 hours.

[0091] (Preparation of laminate (3)) Commercially available polyethylene terephthalate film (product name: "Cosmoshine A4100", thickness: 50 μm, moisture permeability: 13 g / m 2 The aqueous barrier composition of Example 1 was applied to a sheet of paper (manufactured by Toyobo Co., Ltd.) using a wire bar, and then dried in a hot air dryer at 120°C for 3 minutes, resulting in an application amount of 5 g / m. 2 The moisture permeability was measured in the same manner as in the previous paragraph, and it was found to be 4 g / m 2 -Excellent barrier properties were demonstrated for 24 hours.

[0092] (Preparation of laminate (4)) Commercially available triacetyl cellulose film (product name: "FT TD80ULM", thickness: 80 μm, moisture permeability: 330 g / m 2 The aqueous barrier composition of Example 12 was applied to a sheet of paper (manufactured by Fujifilm Corporation) using any wire bar, and then dried in a hot air dryer at 170°C for 3 minutes to obtain a coating amount of 5 g / m. 2 The moisture permeability was measured in the same manner as in the previous paragraph, and it was found to be 4 g / m 2 -Excellent barrier properties were demonstrated for 24 hours.

Claims

1. The composition comprises a urethane resin (A) containing a polyol (a1), a polyisocyanate (a2), and a chain extender (a3) ​​as essential reaction components, and one or more waxes (B) selected from the group consisting of paraffin, carnauba wax, and alkyl ketene dimer, The component (a1) contains a polyether polyol, The component (a3) ​​contains a dialkanolalkanoic acid, An aqueous barrier composition for base paper, wherein the content ratio of component (A) and component (B) by non-volatile weight is (A) / (B)=25 / 75 to 95 / 5.

2. 2. The aqueous barrier composition according to claim 1, wherein the reaction components further comprise a (meth)acrylic acid hydroxyalkyl ester (a4).

3. 3. The aqueous barrier composition according to claim 1, wherein the reaction components further comprise a (meth)acrylic acid alkyl ester (a5) having no hydroxy group.

4. The aqueous barrier composition according to claim 1 or 2, further comprising a rosin-based resin and / or a curing agent.

5. A laminate having a coating of the aqueous barrier composition according to claim 1 or 2 on at least one surface of a base paper.

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