JP7337319B2 - Water vapor barrier composition and water vapor barrier laminate - Google Patents

Description

TECHNICAL FIELD The present invention relates to a steam barrier composition capable of exhibiting high steam barrier properties, and a laminate using the same.

In recent years, as food loss has become a global issue, long-term maintenance of food quality and control of food waste have become issues. In particular, many of the contents used in food packages are degraded by gases such as oxygen and water vapor in the atmosphere, so there is a demand for the development of materials that have high gas barrier properties and transparency comparable to glass.
In order to impart water vapor barrier properties, it is common to use an inorganic material containing a metal such as aluminum, alumina, silica, or the like for the barrier layer. In order to achieve high water vapor barrier properties, the method of forming these inorganic layers on plastic film substrates by vacuum processes such as CVD and vapor deposition is becoming mainstream, but in structures containing inorganic layers, defects such as cracks occur. There were issues such as durability. In order to solve these problems, a multi-layered structure combining an organic layer and an inorganic layer, which takes advantage of the flexibility of organic materials, is being studied. Therefore, it is preferable that the organic layer has a high water vapor barrier property.
Improving the water vapor barrier property of the organic layer not only contributes to solving the food loss problem mentioned above, but also improves the reliability of a wide range of existing products, such as peripheral materials for solar cells, medical products, and food packaging. It is thought that it will also lead to Moreover, if a substrate can be provided with a high water vapor barrier property by a simple coating, it will be a great advantage in manufacturing compared with the method of forming an inorganic layer by a vacuum process.

There are several methods of imparting water vapor barrier properties using organic materials, and among them, it has been reported that high water vapor barrier properties are exhibited when wax is used for the barrier layer (Non-Patent Document 1). However, the content disclosed in Non-Patent Document 1 is limited to the use of wax alone, and no consideration is given to coating suitability, durability and flexibility during formation of a water vapor barrier layer, and the like. On the other hand, as a material having water vapor barrier properties, a composition comprising a combination of polyolefin resin and wax is known. For example, Patent Document 1 discloses a hot-melt type composition for moisture-proof paper comprising a polyolefin resin and wax. However, since it is necessary to heat the base material to a temperature higher than its melting point, a special coating apparatus is required and the process is greatly restricted.

Critical Reviews in Food Science and Nutrition (2002), 42, 67-89

JP 1997-316252

INDUSTRIAL APPLICABILITY The present invention can easily form a water vapor barrier layer composed of an organic material on a base material such as a plastic film or paper by coating, and exhibits higher water vapor barrier properties than conventionally known organic compositions. and a steam barrier laminate using the same.

The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, found that the coexistence of an organic material having a specific structure and a hydrocarbon wax can exhibit a water vapor barrier property, and completed the present invention. reached.

That is, it relates to a steam barrier composition characterized by containing a styrene-based thermoplastic resin (A) and a hydrocarbon-based wax (B).

The steam barrier composition described above is characterized in that the content of the hydrocarbon wax (B) is 5 to 80% by mass based on 100% by weight of the solid content of the steam barrier composition.

The styrene-based thermoplastic resin (A) is a styrene/isoprene/styrene block copolymer (SIS), styrene/isobutylene/styrene (SIBS), or a hydrogenated styrene/ethylene/propylene/styrene block copolymer (SEPS). , styrene-butylene-styrene block copolymer (SBS), hydrogenated styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-butadiene-isoprene-styrene block copolymer (SBIS), or styrene-butylene It is characterized by containing a hydrogenated butadiene/isoprene/styrene block copolymer (SEEPS), a styrene/butadiene copolymer (SB), and acid-modified, acid anhydride-modified, and amine-modified products thereof. with respect to said water vapor barrier composition

The hydrocarbon wax (B) has a melting point of 30° C. to 80° C., and contains 80% by mass or more of the hydrocarbon wax (b1) having a linear structure without branches in the hydrocarbon wax (B). The above water vapor barrier composition is characterized by:

Further, it relates to the above water vapor barrier composition containing a solvent (C).

The present invention relates to a vapor barrier laminate having a vapor barrier composition layer obtained by coating a substrate with the vapor barrier composition described above.

The water vapor barrier laminate, wherein the base material is a resin sheet or a paper base material.

Further, it relates to the above water vapor barrier laminate having at least one layer selected from the group consisting of a heat seal layer, an anchor coat layer, a printing ink layer and a top coat layer.

INDUSTRIAL APPLICABILITY According to the present invention, a water vapor barrier composition and a water vapor barrier laminate can be formed by coating a water vapor barrier layer on a substrate such as a plastic film, and can exhibit higher water vapor barrier properties than conventionally known organic materials. body can be provided.

Embodiments of the present invention will be described below.

The steam barrier composition and steam barrier laminate of the present invention are characterized by containing a styrene-based thermoplastic resin and a hydrocarbon-based wax.

<Styrene-based thermoplastic resin (A)>
The styrenic thermoplastic resin (A) used in the present invention generally has a polystyrene block and a rubber intermediate block. gives rubber elasticity to the product. Intermediate soft segments include polybutadiene (B), isobutylene (IB), polyisoprene (I) and polyolefin elastomers (ethylene/propylene, EP). It is divided into chain (linear type) and radial (radical type). Among the preferred styrene elastomers mentioned above, in the present invention, more specifically, styrene/isobutylene/styrene copolymer (SIBS), styrene/isoprene/styrene block copolymer (SIS), styrene/ethylene/propylene/styrene block copolymer Hydrogenated polymer (SEPS), styrene-butylene-styrene block copolymer (SBS), hydrogenated styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-butadiene-isoprene-styrene block Copolymers (SBIS) or hydrogenated products of styrene/butadiene/isoprene/styrene block copolymers (SEEPS), styrene/butadiene copolymers (SB) and their acid modified products, acid anhydride modified products, amine modified products It can contain one or more selected from the group consisting of the body and the like. However, although not limited to these resins, when a solvent described later is added to form an ink, the styrenic thermoplastic resin (A) may be compatible with the hydrocarbon wax (B) in the ink. preferable.
Commercially available products of such a styrenic thermoplastic resin (A) include, for example, FG1901, FG1924, G1650, D1117, G1643, FG1924, MD1648 manufactured by Kraton Co., Ltd., AR-GB-40 and AR- 1040, AR-NF0-80B, AR-815, AR-8050NC, Kuraray SEPTON1020, SEPTON2002, SEPTON2063, SEPTON HG-252, Asahi Kasei Asaprene T-411, Tuftec H1401, Tuftec H1517, Tuftec MP10, JSR JSRSIS5002 and JSRSIS5506 manufactured by the company, and SIBSTAR072T, SIBSTAR073T and SIBSTAR102T manufactured by Kaneka Corporation.

<Hydrocarbon Wax (B)>
The hydrocarbon wax (B) used in the present invention means an organic substance mainly composed of a long-chain alkyl group skeleton, which is solid at room temperature and becomes liquid when heated. It may contain a group or the like. By adding such a hydrocarbon wax (B) to the styrenic thermoplastic resin (A), it becomes possible to develop a high water vapor barrier property that has not been observed with the resin alone. Here, the factor of the water vapor barrier property due to the hydrocarbon wax (B) is estimated as follows. That is, the water vapor barrier composition of the present invention forms a water vapor barrier composition layer through a heating/drying process after being applied to a substrate described later. The hydrocarbon wax contained in begins to aggregate and form aggregates. Furthermore, it is considered that an oriented structure or crystal structure derived from the high crystallinity of the hydrocarbon wax is formed on the surface during the process of aggregation of the hydrocarbon waxes. As a result, a dense wax layer is formed especially in the vicinity of the interface and surface in the water vapor barrier composition layer described later, and the presence of a hydrophobic and highly crystalline site that makes it difficult for water vapor to permeate suppresses the dissolution and diffusion of water vapor. , it is considered that excellent water vapor barrier properties are exhibited.

Specific examples of the hydrocarbon wax (B) include natural and synthetic waxes such as paraffin wax, microcrystalline wax, beeswax, montan wax, ozokerite, ceresin, carnauba wax, candelilla wax, beeswax, Japan wax, and rice wax. It can contain one or more selected from the group consisting of, but not limited to. The hydrocarbon wax (B) preferably dissolves uniformly in the water vapor barrier composition. Examples of commercially available natural wax include paraffin wax and microcrystalline wax manufactured by Nippon Seiro Co., Ltd. and ENEOS. In addition, FT115, FT0165, SX105, FNP0090 manufactured by Nippon Seiro Co., Ltd., CERAMER polymer manufactured by Baker Hughes, POLYWAX polyethylene, UNICID carboxylic acid, UNILIN alcohol, UNITHOX ethoxylate, PETROLITE copolymer, VYBAR polymer, Diacarna manufactured by Mitsubishi Chemical. , Sanyo Chemical Co., Ltd. Sanwax series, Viscol series, and other synthetic waxes. Furthermore, using these as raw materials, oxidized waxes produced by chemical reactions such as oxidation, saponification, esterification, maleation, and acid anhydride formation, blended waxes in which these are blended with resins, etc., and these waxes dispersed in water The emulsion wax obtained by mixing is also included in the hydrocarbon wax (B) of the present invention.

In order for the hydrocarbon wax to exhibit good water vapor barrier properties, the hydrocarbon wax preferably has a melting point of 30° C. or higher and 80° C. or lower, more preferably 40° C. or higher and 70° C. or lower. Further, it is preferable that 80% by mass or more of the hydrocarbon wax (B) has a straight chain structure without branches, and more preferably 90% or more has a straight chain structure without branches. In addition, wax-like olefins having a double bond in the molecule are also used as the hydrocarbon wax (B) as a hydrocarbon material that is solid at room temperature and exhibits similar properties with a melting point of 30°C to 80°C. including mixtures thereof. Among the above hydrocarbon waxes (B), paraffin wax and microcrystalline wax are preferred, and paraffin wax is most preferred. Since these have excellent crystallinity, they can particularly promote the formation of a wax aggregate structure in the water vapor barrier composition of the present invention.

The content of the hydrocarbon wax (B) is preferably 5 to 80% by mass, more preferably 8 to 50% by mass, when the total solid content of the steam barrier composition is 100% by mass. . Within this range, the water vapor barrier composition of the present invention has improved miscibility with other components, and the water vapor barrier laminate can exhibit superior water vapor barrier properties.

<Solvent (C)>
The solvent (C) used in the water vapor barrier composition used in the present invention includes, for example, organic solvents such as methyl acetate, ethyl acetate, normal propyl acetate, normal butyl acetate, isobutyl acetate, propyl acetate, ethyl cellosolve acetate, normal Ester solvents such as propyl acetate, isopropyl acetate, isobutyl acetate, propylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, methyl alcohol, ethyl alcohol, isopropyl alcohol, normal propanol, normal butanol, normal propyl alcohol, propylene glycol monoethyl known alcohol solvents such as ether and propylene glycol monomethyl ether; ketone solvents such as acetone, methyl ethyl ketone, cyclohexanone, and methyl isobutyl ketone; and hydrocarbon solvents such as toluene, benzene, cyclohexane, hexane, methylcyclohexane, and ethylcyclohexane. of solvents can be used. These can be used alone or in combination of two or more as the solvent (C).
Among these solvents (C), in order to form the aggregate structure of the hydrocarbon wax described above, the compatibility with the styrenic thermoplastic resin or the hydrocarbon wax in the water vapor barrier composition is relatively high. An organic solvent having a dispersion force term δd of 14 or more and a dipole force term δp of 3 or less in the Hansen solubility parameter (HSP value) is used because it is high and can improve the crystallization and surface migration of the wax after drying. It is more preferable to use an organic solvent (C1) having a dispersion force term δd of 15 or more and a dipole force term δp of 4 or less, and the solvent (C) contains 50% or more of these organic solvents. is preferred. Examples of organic solvents having an HSP value dispersion force term δd of 15 or more and a dipole force term δp of 4 or less include nonpolar solvents such as toluene, methylcyclohexane, cyclohexane, heptane, octane, and hexane. . The HSP value is obtained by dividing the solubility parameter introduced by Hildebrand into three components, ie, the dispersion force term δd, the polarity term δp, and the hydrogen bond term δh, and considering the polarity of the substance. As the HSP value, a known value may be used, or personal computer software HSPiP (source: http://www.hansen-solubility.com/index.html) or the like may be used.
The weight of the solvent (C) is not particularly limited, but the content of the solvent in the water vapor barrier composition is preferably 50 to 95% by weight.
Further, when the organic solvent (C1) is used, it is preferably 50 to 100% by mass in the solvent (C).

<Other ingredients>
Various additives can be added to the water vapor barrier composition, as long as they do not impair the effects of the present invention. For example, curing agents such as polyisocyanates, epoxy resins, polycarbodiimide compounds, organic or Inorganic fillers and liquid rubbers can be blended. Such fillers may be composed of materials such as polymers, ceramics, metals, metal oxides, metal salts, and dyes and pigments. Moreover, the shape is not particularly limited, and may be, for example, particulate or fibrous. In addition, silane coupling agents, titanate coupling agents, flame retardants, storage stabilizers, antioxidants, and metal deactivators are used for leveling with substrates, adjusting coating properties, and improving adhesion. Agents, UV absorbers, thixotropy-imparting agents, leveling agents, anti-foaming agents, dispersion stabilizers, fluidity-imparting agents, anti-foaming agents, colorants and the like can also be added. Further, a liquid rubber or a softening agent may be included in order to improve fluidity and adhesiveness.

<Water vapor barrier composition>
The water vapor barrier composition of the present invention is produced by mixing the styrene thermoplastic resin (A), the hydrocarbon wax (B), and other optional components using a roll, a stirrer, a melting kiln, or the like. However, it is not particularly limited, and any method can be used as long as these components can be uniformly mixed. A solvent (C) may be added to the water vapor barrier composition used in the present invention if necessary. A hot-melt type may also be used. In addition, the water vapor barrier composition used in the present invention is formed on a substrate or a laminate sheet containing a layer other than a substrate and a water vapor barrier composition layer by mixing an optional curing agent component, and then a curing (crosslinking) reaction is performed. It can also be a curable composition that receives

The steam barrier composition of the present invention can also be obtained by uniformly mixing the styrene-based thermoplastic resin (A), the hydrocarbon-based wax (B), the solvent (C), and other optional ingredients used as necessary. be able to. By adding a solvent to the water vapor barrier composition to form an ink from the viewpoint of imparting coating suitability, it becomes possible to form a layer of the water vapor barrier composition on a substrate by the coating method described below. As a method for uniformly mixing, a kiln equipped with an agitator such as a planetary mixer or a disper, or a glass bottle may be used, such as a ball mill, bead mill, roller mill, pebble mill, attritor, sand mill, etc. distributed processing may be applied. In the stirring and dispersing steps described above, the styrene-based thermoplastic resin (A) or the hydrocarbon-based wax (B) may not necessarily be completely dissolved, and may form a fine particle emulsion. If the water vapor barrier composition contains air bubbles or unexpectedly large particles, it is preferable to remove them by filtration or the like, because the quality of the coated product is deteriorated. A conventionally known filter can be used.

<Base material>
Examples of the substrate include a resin sheet, paper, aluminum sheet (aluminum foil), and the like. For example, resin sheets include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polycarbonate resins, polyarylate resins, acrylic resins, polyphenylene sulfide resins, polystyrene resins, and vinyl resins. , vinyl chloride resins, polyimide resins, epoxy resins, and polyolefin resins such as polyethylene, polypropylene, and polynorbornene. Moreover, a laminate obtained by laminating metal on these sheets may be used, and a laminate obtained by laminating aluminum on a polyethylene terephthalate (PET) sheet, for example, may be used. Among the substrates, polypropylene, polyethylene terephthalate, polyethylene and the like are preferable because a laminated sheet having good stretchability, translucency and rigidity can be obtained.
The base material may contain one or more optional components as long as the effects of the present invention are not impaired. The substrate used in the present invention may contain ultraviolet absorbers, antioxidants, antistatic agents, surfactants, pigments, fluorescent whitening agents, and the like. The substrate may contain inorganic particles containing silica, calcium carbonate, titanium oxide, or the like, or organic particles containing acrylic resin, styrene resin, or the like.

(Paper substrate)
The paper substrate is not particularly limited, and is not particularly limited as long as it is mainly composed of plant-derived pulp. Specific examples of paper substrates include bleached or unbleached kraft paper, woodfree paper, paperboard, liner paper, coated paper, single-glazed paper, glassine paper, graphane paper, and the like. The thickness of the paper substrate may be, for example, 30 μm or more and 100 μm or less, or 30 μm or more and 70 μm or less. Moreover, the thickness of the paper substrate may be 70% or more of the thickness of the entire laminate. If the thickness of the paper substrate is 70% or more of the thickness of the entire laminate, it can be said to be excellent in environmental suitability.

The basis weight of the base paper can be appropriately selected according to various qualities and handleability desired for the barrier material, but it is usually preferable to have a basis weight of 20 g/m ² or more and 600 g/m ² or less. In the case of packaging materials used for packaging purposes, such as packaging materials for foods, bags, paper containers, corrugated boxes, and cups, those with a weight of 25 g/m ² or more and 600 g/m ² or less are more preferable.

<Water vapor barrier laminate>
The water vapor barrier laminate of the present invention has a water vapor barrier composition layer formed by coating a water vapor barrier composition on one or both sides of a substrate. The method for applying the water vapor barrier composition is not particularly limited and includes printing methods, and known coating methods can be used. Coating methods include wire bar coating, die coating, cast coating, slot coating, omega coating, spiral coating, control seam coating, slot coating, dot coating, hot melt applicator coating, and hot melt coating. Melt coater coating method, blade coat coating method, dip coating method, gravure coat coating method, micro gravure coating method, curtain spray coating method, bead coating method, hot melt roll coater coating method, spin coat coating method, printing method Inkjet printing method, spray printing method, roll coat printing method, doctor roll printing method, doctor blade printing method, curtain coat printing method, slit coat printing method, screen printing method, reverse printing method, push coat printing method, slit coater A printing method and the like can be mentioned. After the water vapor barrier laminate is applied to the base material by these methods, it may be dried by heating or dried under reduced pressure, if necessary, for the purpose of removing the solvent (C) or promoting cross-linking. . The drying conditions are not particularly limited as long as the substrate is not deteriorated depending on the film thickness, the substrate and the selected organic solvent.

When a resin sheet is used as the base material, the thickness of the water vapor barrier composition layer is not particularly limited, but it is preferably a thin film for the purpose of suppressing cracks and the like during bending. It is preferably 0.5 to 10 μm, more preferably 1.0 to 5.0 μm.

When a paper substrate is used as the base material, the coating amount of the water vapor barrier composition is not particularly limited, but the larger the coating amount, the more uniformly the water vapor barrier layer is formed on the paper base material permeated with the water vapor barrier composition. It is possible to develop sufficient water vapor barrier performance. Therefore, when the water vapor barrier composition is applied directly onto the paper substrate, the coating amount of the water vapor barrier composition in a dry state is preferably 3.5 to 15.0 g/m ² , more preferably 4.0 to 10.0 g/m 2 . /m ² is more preferred, and 4.5 to 8.0 g/m ² is even more preferred.

In addition, the water vapor barrier composition layer formed here may be laminated as a single layer or a plurality of layers on one side or both sides of the substrate. When multiple layers of water vapor barrier composition layers are provided, their compositions may be the same or different. For example, after coating the water vapor barrier composition on one side of the base material, the same water vapor barrier composition layer may be formed in the same process through a drying step, and two layers may be formed, or further different layers may be formed. Three layers may be formed by forming the water vapor barrier composition layer.

In addition to the base material and the water vapor barrier composition layer, the water vapor barrier laminate can be provided with any organic layer or inorganic layer. An overcoat layer etc. are mentioned. These layers can include one layer or multiple layers. The arbitrary layer referred to here is not particularly limited, but may be formed directly on the base material layer, or may be formed via a water vapor barrier composition layer. From the viewpoint of protecting the barrier composition layer or improving wear resistance, a protective layer and an adhesive layer may be provided on the water vapor barrier composition layer, if necessary. Also, the anchor coat layer is preferably formed between the water vapor barrier composition layer and the substrate layer, and the top coat layer is preferably formed on the water vapor barrier composition layer formed via the substrate. .

Examples of the structure of the laminate include substrate/water vapor barrier composition layer, substrate/printing ink layer/water vapor barrier composition layer, substrate/anchor coat layer/water vapor barrier composition layer, and substrate/water vapor barrier composition. Layer/topcoat layer, substrate/printing ink layer/anchor coat layer/water vapor barrier composition layer, substrate/printing ink layer/anchor coat layer/water vapor barrier composition layer/topcoat layer, substrate/anchor coat layer /printing ink layer/water vapor barrier composition layer, substrate/anchor coat layer/printing ink layer/water vapor barrier composition layer/top coat layer, substrate/water vapor barrier composition layer/printing ink layer, substrate/water vapor barrier Composition layer/printing ink layer/topcoat layer, heat seal layer/base material/water vapor barrier composition layer, heat seal layer/base material/printing ink layer/water vapor barrier composition layer, heat seal layer/base material/anchor Coat layer/water vapor barrier composition layer, heat seal layer/base material/water vapor barrier composition layer/top coat layer, heat seal layer/base material/printing ink layer/anchor coat layer/water vapor barrier composition layer, heat seal layer /base material/printing ink layer/anchor coat layer/water vapor barrier composition layer/top coat layer, heat seal layer/base material/anchor coat layer/printing ink layer/water vapor barrier composition layer, heat seal layer/base material/ Anchor coat layer/printing ink layer/water vapor barrier composition layer/topcoat layer, heat seal layer/base material/water vapor barrier composition layer/printing ink layer, heat seal layer/base material/water vapor barrier composition layer/printing ink Layer/top coat layer, heat seal layer/water vapor barrier composition layer/substrate, heat seal layer/water vapor barrier composition layer/substrate/printing ink layer, heat seal layer/water vapor barrier composition layer/substrate/top Coat layer, heat seal layer/water vapor barrier composition layer/substrate/printing ink layer/topcoat layer. Barrier composition layer, substrate/anchor coat layer/water vapor barrier composition layer, substrate/water vapor barrier composition layer/topcoat layer, substrate/printing ink layer/anchor coat layer/water vapor barrier composition layer, substrate /printing ink layer/anchor coat layer/water vapor barrier composition layer/topcoat layer, substrate/anchor coat layer/printing ink layer/water vapor barrier composition layer, substrate/anchor coat layer/printing ink layer/water vapor barrier composition Material layer/top coat layer, base material/water vapor barrier composition layer/printing ink layer/top coat layer, heat seal layer/base material/printing ink layer/water vapor barrier composition layer, heat seal layer/base material/anchor coat Layer/water vapor barrier composition layer, heat seal layer/base material/water vapor barrier composition layer/top coat layer, heat seal layer/base material/printing ink layer/anchor coat layer/water vapor barrier composition layer, heat seal layer/ Base material/printing ink layer/anchor coat layer/water vapor barrier composition layer/top coat layer, heat seal layer/base material/anchor coat layer/printing ink layer/water vapor barrier composition layer, heat seal layer/base material/anchor Coat layer/printing ink layer/water vapor barrier composition layer/topcoat layer, heat seal layer/substrate/water vapor barrier composition layer/printing ink layer/topcoat layer, heat seal layer/water vapor barrier composition layer/substrate , Heat seal layer/water vapor barrier composition layer/base material/printing ink layer, heat seal layer/water vapor barrier composition layer/base material/top coat layer, heat seal layer/water vapor barrier composition layer/base material/printing ink A layer/topcoat layer is more preferred.

When a resin sheet is used as the base material, the thickness of the laminate when any layer is provided is not particularly limited. ~5.0 μm is more preferred. In the case of a laminate in which an anchor coat layer is formed between a paper base material and a water vapor barrier layer, the coating amount of the water vapor barrier composition is not particularly limited, but is 0.5 to 10.0 g/m ² in a dry state. It is preferably 1.0 to 7.0 g/m ² and even more preferably 1.5 to 6.5 g/m ² .

The method of laminating the organic layer or the inorganic layer is not particularly limited. It may be a laminate including layers formed by a vacuum process such as.

Materials for the organic layer include polyvinyl alcohol-based resins, polyolefin-based resins (polyethylene, polypropylene, poly-4-methyl-1-pentene, polybutene, etc.), cyclic olefin-based resins, polyester-based resins (polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, etc.), polyamide-based resins (nylon-6, nylon-66, and polymetaxylene adipamide, etc.), polyacetal-based resins, polyacrylic acid-based resins, polyurethane-based resins, polyvinylpyrrolidone-based resins, polysulfonic acid system, starch-based resin, cellulose-based resin, polyvinyl chloride-based resin, polyvinyl acetate-based resin, polyphenylene sulfide-based resin, phenol-based resin, styrene-based resin, silicone-based resin, epoxy-based resin, polycarbonate-based resin, ionomer-based resin , alkyd-based resins, diallyl phthalate-based resins, melamine-based resins, polyacrylonitrile-based resins, polycaprolactone-based resins, polyethyleneimine-based resins, polyimide-based resins, and the like. These may be used alone or in combination of two or more. Materials for the inorganic layer include metals and semi-metals such as chromium, titanium, zinc, cobalt, copper, silver, aluminum, tin and silicon, or the aforementioned metals and semi-metals such as silica, alumina, titanium oxide, zinc oxide and silicon nitride. Metal oxides, nitrides, nitrates, sulfides, phosphides, and the like are included. These may be used alone or in combination of two or more.
When one or more layers of the water vapor barrier composition layer and one or more layers of organic or inorganic layers are included on one or both sides of the substrate, the lamination order of these layers is arbitrary.

<Anchor coat layer>
The anchor coat layer is formed between the base material and the water vapor barrier layer to improve the adhesion of the water vapor barrier layer to the base material. When a paper base material is used as the base material, an anchor coat layer is formed between the base material and the water vapor barrier layer. Even if it is reduced, sufficient water vapor barrier performance can be exhibited, and the water resistance of the laminate can be improved. As the anchor coating agent used for forming the anchor coat layer, an oily anchor coating agent or a water-based anchor coating agent can be used. In the case of a laminate in which an anchor coat layer is formed between a paper base material and a water vapor barrier layer, the coating amount of the anchor coat agent used for the anchor coat layer is not particularly limited, but is 0.5 to 10.0 g in a dry state. /m ² is preferred, 1.0 to 7.0 g/m ² is more preferred, and 1.5 to 6.5 g/m ² is even more preferred.

<Oil-based anchor coating agent>
Examples of binder resins used in oily anchor coating agents include, but are not limited to, polyurethane resins, cellulose resins, polylactic acid resins, polyamide resins, vinyl chloride-vinyl acetate copolymer resins, vinyl chloride - acrylic copolymer resins, rosin resins, ethylene-vinyl acetate copolymer resins, vinyl acetate resins, acrylic resins, styrene resins, dammar resins, styrene-maleic acid copolymer resins, polyester resins, alkyd resins, terpene resins, Phenol-modified terpene resins, ketone resins, cyclized rubbers, chlorinated rubbers, butyral, polyacetal resins, petroleum resins, modified resins thereof, and the like, and these resins are used alone or in combination of two or more. be able to. Polyurethane resins, cellulose resins, and polylactic acid resins are preferred, and polyurethane resins are particularly preferred.

<Polyurethane resin>
The polyurethane resin preferably has a weight average molecular weight of 10,000 to 100,000 and a glass transition temperature of 0° C. or lower. -60°C to 0°C is more preferred, and -40 to -5°C is even more preferred.
The polyurethane resin preferably has an amine value and/or a hydroxyl value, and the amine value is preferably 0.5 to 30 mgKOH/g, more preferably 1 to 20 mgKOH/g. Also, the hydroxyl value is preferably 0.5 to 30 mgKOH/g, more preferably 1 to 20 mgKOH/g. Within the above range, the adhesiveness to the substrate is improved.

The polyurethane resin preferably contains a structural unit derived from polyether polyol and/or polyester polyol, and the total content thereof is preferably 5 to 80% by mass based on 100% by mass of the solid content of the polyurethane resin. It is preferably 10 to 60% by mass, more preferably 10 to 50% by mass.

The polyurethane resin is not particularly limited, and can be produced as appropriate by a known method. A polyurethane resin comprising a polyol and a polyisocyanate, and a polyurethane resin obtained by reacting an isocyanate-terminated urethane prepolymer comprising a polyol and a polyisocyanate with a polyamine are preferred. Examples of the manufacturing method include the method described in JP-A-2013-256551.

<Cellulose resin>
Cellulosic resins include, for example, nitrocellulose, cellulose acetate propionate, cellulose acetate butyrate, hydroxyalkyl cellulose, carboxyalkyl cellulose, etc. Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, A butyl group, an isobutyl group, a pentyl group, a hexyl group and the like can be mentioned, and the alkyl group may further have a substituent. Among them, cellulose acetate propionate, cellulose acetate butyrate, and nitrocellulose are preferred. As for the molecular weight, the weight average molecular weight is preferably 5,000 to 1,000,000, more preferably 10,000 to 200,000. Further, those having a glass transition temperature of 100° C. to 160° C. are preferable.

<Polylactic acid resin>
Polylactic acid resin is a biomass plastic that uses plant-derived starch and sugar as raw materials and has a main skeleton of polylactic acid that is manufactured through a chemical process. Hydrolysis is promoted by placing it in an environment with moderate moisture and temperature, such as compost or soil, and then decomposition by microorganisms (biodegradation) progresses, and finally completely decomposes into CO2 and water. It is a biodegradable resin that Industrially, it is a polyester resin synthesized from lactide, which is a cyclic dimer of lactic acid made from starch produced from corn or the like. The polylactic acid resin preferably contains 70 to 100% by mass, more preferably 90 to 100% by mass, of structural units derived from polylactic acid based on the total polylactic acid resin.

<Aqueous anchor coating agent>
A water-based resin can be suitably used as the binder resin used in the water-based anchor coating agent, and the term "aqueous" means water-soluble or in an emulsion state. As the water-based resin, at least one water-based resin selected from water-soluble resins and emulsion resins can be suitably used, and a mixture thereof may also be used. Examples of water-based resins include water-based polyurethane resins, water-based acrylic-modified urethane resins, water-based acrylic-modified urethane urea resins, water-based acrylic resins, water-based styrene-acrylic acid copolymer resins, water-based styrene-maleic acid copolymer resins, and water-based ethylene-acryl. acid copolymer resin, aqueous polyester resin, aqueous shellac, aqueous rosin-modified maleic acid resin, aqueous vinyl chloride-vinyl acetate copolymer resin, aqueous vinyl chloride-acrylic acid copolymer resin, aqueous chlorinated polypropylene resin, aqueous hydroxyethyl cellulose resin, Water-based hydroxypropyl cellulose resins, water-based butyral resins, and the like can be preferably used. These resins can be used alone or in combination of two or more.
Among them, it is preferable to contain at least one water-based resin selected from water-based polyurethane resin, water-based acrylic resin, water-based styrene-acrylic acid copolymer resin, and water-based styrene-maleic acid copolymer resin. These are preferably contained in an amount of 50% by mass or more, more preferably 70% by mass or more, and still more preferably 80% by mass or more in the total mass of the binder resin. In particular, it is preferable to contain an aqueous urethane resin.

(Aqueous polyurethane resin)
From the viewpoint of adhesion to the substrate and pigment dispersibility, the binder resin preferably contains an aqueous polyurethane resin. The water-based polyurethane resin has an acid value to be neutralized, and preferably has an acid value of 20 to 65 mgKOH/g. Also, the glass transition temperature is preferably -30 to 0°C. Here, the glass transition temperature means the maximum value of Tan δ in dynamic viscoelasticity measurement. A hydroxyl value of 1 to 15 mgKOH/g is preferable.

The water-based polyurethane resin may be in the form of a polyurethane resin synthesized from a polyol, a hydroxy acid and a polyisocyanate, or a urethane prepolymer having an isocyanate group at the end synthesized from a polyol, a hydroxy acid and a polyisocyanate and chain-extended with a polyamine. A preferred embodiment is a polyurethane resin containing polyurethane urea.

<Water vapor permeability>
The water vapor transmission rate varies depending on the type of resin or the amount of wax blended, but when a resin sheet is used as the base material of the laminate, the preferred range is less than 10.0 g/m ² ·day for the water vapor barrier composition layer alone. and more preferably less than 1.0 g/m ² ·day. When a paper base material is used as the base material of the laminate, the value of the water vapor barrier composition layer alone is preferably less than 200.0 g/m ² ·day, more preferably 100.0 g/m ² ·day. is less than
A detailed method for measuring the water vapor transmission rate will be specifically described in Examples.

EXAMPLES Hereinafter, the present invention will be described specifically and in detail with reference to examples, but these examples are merely one aspect of the present invention, and the present invention is not limited by these examples. In the table, "part" means "mass part" and "%" means "mass %".

The abbreviations of the aliphatic hydrocarbon-based styrenic thermoplastic resin (A), the hydrocarbon-based wax (B), the solvent (C), and other components and constituent elements described in the examples and Table 1 below are shown below. .
<Styrene-based thermoplastic resin (A)>
・A-1: Kraton Co., Ltd. Product name: G1650 (hydrogenated styrene/ethylene/butylene/styrene block copolymer)
・A-2: Kraton Co., Ltd. Product name: FG1924 (hydrogenated maleic anhydride-modified styrene/ethylene/butylene/styrene block copolymer)
・A-3: Kuraray Co., Ltd. Product name: SEPTON 2063 (hydrogenated styrene/ethylene/butylene/styrene block copolymer)
・A-4: Kaneka Corporation Product name: SIBSTAR 073T (styrene/isobutylene/styrene block copolymer)

<Hydrocarbon Wax (B)>
・ B-1: Nippon Seiro Co., Ltd. Product name: Paraffin Wax 115 (melting point: 48 ° C., content ratio of linear structure component: 91% or more)
・ B-2: Nippon Seiro Co., Ltd. Product name: Paraffin Wax 135 (melting point: 59 ° C., content ratio of linear structure component: 92% or more)
・ B-3: Nippon Seiro Co., Ltd. Product name: Paraffin Wax 155 (melting point: 69 ° C., content ratio of linear structure component: 90% or more)
・ B-4: Nippon Seiro Co., Ltd. Product name: Hi-Mic 2065 (melting point: 75 ° C., content ratio of linear structure component: 81% or more)
・ B-5: Nippon Seiro Co., Ltd. Product name: Hi-Mic 2045 (melting point: 72 ° C., content ratio of linear structure component: 80% or more)

<Solvent (C)>
· C-1: toluene (δd: 18.0, δp: 1.4)
· C-2: MCH (methylcyclohexane) (δd: 16.0, δp: 0)
· C-3: isobutyl acetate (δd: 15.1, δp: 3.7)
· C-4: butyl acetate (δd: 15.8, δp: 3.7)
· C-5: toluene / isobutyl acetate = 1/1 (mass ratio) (δd: 16.6, δp: 2.6)
· C-6: MCH / butyl acetate = 1/1 (mass ratio) (δd: 15.9, δp: 1.9)

<Resin sheets (D-1) to (D-3) and laminated sheets (D-4) (D-5)>
・ D-1: Toray Industries, Inc. Product name: Lumirror S10 (100 μm PET film)
・D-2: Futamura Chemical Co., Ltd. Product name: FOH (30 μm OPP film)
・D-3: Toyobo Co., Ltd. Product name: E5102 (25 μm PET film)
・ D-4: Laminated sheet coated with gravure ink (Toyo Ink Co., Ltd. product name: Real NEX 39 Indigo BO S3) on D-1 (Lumirror S10) ・ D-5: D-2 (FOH) Laminated sheet coated with gravure ink (Toyo Ink Co., Ltd. product name: Real NEX 39 Indigo BO S3)

<Paper base material (D-6) (D-7)>
・ D-6: Daio Paper Co., Ltd. Product name: Nagoya Sarashi Ryuo (single glossy paper weighing 70 g)
・ D-7: Nippon Paper Industries Co., Ltd. Product name: npi fine quality (high quality paper weighing 64 g)

<Other components (E)>
・E-1: Idemitsu Kosan Co., Ltd. Product name: Diana Process Oil PW90 (softener)
・ E-2: BASF Japan Ltd. Product name: Irganox 1010 (antioxidant)
・E-3: Sigma-Aldrich Poly (vinyl acetate)
・E-4: Daiichi Kogyo Seiyaku Co., Ltd. Product name: PLYSURF A212 (Heat resistance improver)
・ E-5: Mizusawa Chemical Industry Co., Ltd. Product name: Mizukasil P707 (adhesion improver)

<Anchor coating agent (F)>
・F-1: Oil-based urethane-based (BPU410) anchor coating agent of Production Example 1 ・F-2: Oil-based PLA-based anchor coating agent of Production Example 2 ・F-3: Oil-based cellulose-based anchor coating agent (NV.30%, Nitrogen content 11.5% or more and 12.2% or less, weight average molecular weight 28,000 to 33,000)
・ F-4: Aqueous urethane-based (JW303) anchor coating agent of Production Example 4

<Production Example 1: Production method of F-1 oil-based urethane anchor coating agent>
(Synthesis of urethane resin)
Biomass sebacic acid/adipic acid = 50/50 (mass ratio) and 1,3-propanediol/neopentyl glycol = 50/ 24.3 parts of a polyester polyol having a number average molecular weight of 2,000 obtained by condensation polymerization of 50 (mass ratio), 4 parts of isophorone diisocyanate, and 10 parts of ethyl acetate were charged, and the mixture was heated at 120°C for 6 hours under a stream of nitrogen. After reacting, 14 parts of propyl acetate was added and cooled to obtain a solution of a terminal isocyanate prepolymer. Then, to a mixture of 1.7 parts of isophoronediamine (hereinafter also abbreviated as IPDA), 18 parts of ethyl acetate and 28 parts of isopropyl alcohol (hereinafter also abbreviated as IPA), the obtained solution of the terminal isocyanate prepolymer was gradually added at room temperature. Then, it was reacted at 50° C. for 1 hour to obtain a urethane resin solution having a solid content of 30%, a mass average molecular weight of 70,000 and an amine value of 5 mgKOH/g.

(Manufacturing of oil-based urethane anchor coating agent)
Urethane resin solution 20 parts, vinyl chloride-vinyl acetate resin solution 10 parts, silica particles (average particle diameter 5 μm BET specific surface area 200 m / g) 1 part, mixed solvent (propyl acetate (NPAC) / IPA = 70/30 (mass ratio ))) 26 parts were stirred and mixed and kneaded in a sand mill, then 20 parts of urethane resin solution, mixed solvent (propyl acetate/IPA = 70/30 (mass ratio)) 19.7 parts, polyalkyl vinyl ether (polyvinyl butyl ether copolymer Combined number average molecular weight 5,000 solid content 20%) 0.1 part, water 3.0 parts, quaternary ammonium salt (lauryltrimethylammonium chloride solid content 50%) 0.2 parts were stirred and mixed, and an oil-based urethane anchor was obtained. A coating agent was obtained.

<Production Example 2: Production method of F-2 oil-based PLA-based anchor coating agent>
(Synthesis of polylactic acid resin)
100 parts of M-lactide and 0.1 part of octanol are charged in a four-necked flask equipped with a stirrer, thermometer, reflux condenser and nitrogen gas inlet tube, and after reaching 180° C., tin 2-ethylhexanoate is added in 0.05 part. After ring-opening polymerization was carried out for 2 hours, 0.08 part of 116% strong phosphoric acid was added to remove residual lactide under reduced pressure. of polylactic acid resin solution was obtained.

(Production of oil-based PLA-based anchor coating agent)
Nitrocellulose (NV.30%, nitrogen content 11.5% to 12.2%, weight average molecular weight 28,000 to 33,000) 33.3 parts, ethyl acetate 39.9 parts, polylactic acid resin solution (NV .50%) 20.0 parts, ORGATICS TC-100 (Titanium chelate NV.75% manufactured by Matsumoto Fine Chemical Co., Ltd.) 0.9 parts, diethylene glycol monobutyl ether 2.0 parts, Sanwax 131P (polyethylene wax NV.40%) 3.9 parts were stirred and mixed to obtain an oily PLA anchor coating agent.

<Production Example 3: Production method of F-4 water-based urethane anchor coating agent>
(Synthesis of urethane resin)
Poly(3-methyl-1,5-pentaneadipate) diol having a number average molecular weight of 400, 96.89, while introducing nitrogen gas in a reactor equipped with a thermometer, stirrer, reflux condenser and nitrogen gas inlet. 24.18 parts of polyethylene glycol having a number average molecular weight of 2000, 21.56 parts of 2,2-dimethylolpropionic acid and 138.24 parts of isophorone diisocyanate were reacted at the boiling point in 200 parts of methyl ethyl ketone for 6 hours to form a terminal isocyanate prepolymer. After cooling to 40° C., 100 parts of acetone was added to obtain a solvent solution of a terminal isocyanate prepolymer. Next, to a mixture of 14.35 parts of 2-hydroxyethylethylenediamine, 4.78 parts of isophoronediamine and 400 parts of acetone, 580.87 parts of the obtained terminal isocyanate prepolymer solution was gradually added at room temperature. A reaction was carried out at 50° C. for 3 hours to obtain a solvent-type polyurethane resin solution. Next, 9.76 parts of 28% aqueous ammonia and 700 parts of deionized water were gradually added to the above solvent-type polyurethane resin solution to neutralize it, and then the total amount of methyl ethyl ketone and acetone was distilled off under azeotropic conditions. After removing the solvent, water was added to adjust the viscosity to obtain a polyurethane resin having an acid value of 30 mgKOH/g, a solid content of 30%, a viscosity of 780 mPa·s and a weight average molecular weight of 22,000.

(Production of water-based urethane anchor coating agent)
30.00 parts of polyurethane resin, 0.10 parts of antifoaming agent, 10.00 parts of isopropyl alcohol, and 29.90 parts of water were stirred and mixed and kneaded with a sand mill, followed by 20.00 parts of polyurethane resin solution (PU01), isopropyl 5.00 parts of alcohol and 10.00 parts of water were stirred and mixed to obtain a water-based urethane anchor coating agent.

[Preparation of water vapor barrier coating agent and production of water vapor barrier sheet]
<1. Example using a resin sheet>
<Example 1>
75 parts of styrene thermoplastic resin (A-1) (copolymer), 25 parts of hydrocarbon wax (B-1), and 400 parts of solvent (C-1) are added to a glass bottle and dissolved. to obtain a water vapor barrier composition. The prepared water vapor barrier composition was applied onto the substrate (D-1) using a bar coater or an applicator and dried in a hot air oven at 70° C. for 5 minutes to obtain a water vapor barrier laminate. The thickness of the water vapor barrier layer in the water vapor barrier laminate after drying was 3.0 μm.

Next, the obtained laminate was used to conduct the following tests.
<Measurement of water vapor transmission rate>
The water vapor barrier property of the resin sheet was evaluated using a water vapor permeability measuring device (Permatran manufactured by MOCON) under the conditions of a permeation area of 50 cm ² , 40°C, a humidity of 100% (saturated water vapor pressure), and a nitrogen flow rate of 10 sccm. It was carried out by measuring the From the obtained water vapor permeability, the contribution of the water vapor permeability of the base material was removed, and the water vapor permeability of the water vapor barrier composition layer alone was calculated and evaluated according to the following four levels.
◎: Water vapor permeability is less than 1.0 g/(m ² ·day) ○: Water vapor permeability is 1.0 g/(m ² ·day) or more and less than 5.0 g/(m ² ·day) △: Water vapor permeability of 5.0 g/(m ² ·day) or more and less than 10.0 g/(m ² ·day) ×: Water vapor permeability of 10.0 g/(m ² ·day) or more

<Measurement of adhesion>
In the laminate thus produced, a cellophane tape (made by Nichiban, width 12 mm) was attached to the surface opposite to the base material while being rubbed five times with a thumb. The operation of separating the cellophane tape from the laminate was carried out three times, and the adhesion to the substrate was visually evaluated. Judgment criteria are shown below.
⊚: The coating agent did not peel off three times by rapid pulling.
◯: The coating agent peeled off once or more and less than 3 times by rapid pulling.
Δ: The coating agent was peeled off three times by abrupt pulling, and the coating agent was not peeled off by pulling gradually.
x: The coating agent was peeled off three times by abrupt pulling, and the coating agent was peeled off by pulling gradually three times.

<Evaluation of Haze>
Using a haze meter (manufactured by Nippon Denshoku Industries, trade name: SH7000), the produced laminate was evaluated by T.I. T. (total light transmittance) and Dif. (Diffuse transmittance) was measured and evaluated according to three stages of judgment criteria using the calculated value of the following formula.
HAZE=Dif. /T. T.
◎: 1 or more and less than 10 ○: 10 or more and less than 15 △: 15 or more

<Examples 2 to 65, Comparative Example 1>
As shown in Table 1, the barrier composition was prepared and the resin sheet was used in the same manner as in Example 1, except that the type and amount of raw material of the water vapor barrier composition and the type of base material of the barrier laminate were changed. A barrier laminate was produced, and the water vapor barrier property, adhesion, and haze were evaluated. Table 1 shows the results.

<2. Example using paper substrate>
<Example 66>
In a glass bottle, 70 parts of the polymer (A-1), 30 parts of the hydrocarbon wax (B-1) and 400 parts of the solvent (C-1) were added and dissolved to obtain a water vapor barrier composition. The prepared water vapor barrier composition was applied onto the substrate (D-6) using a bar coater or an applicator and dried in a hot air oven at 70° C. for 5 minutes to obtain a water vapor barrier laminate. The thickness of the water vapor barrier layer in the water vapor barrier laminate after drying was 5.1 μm.

<Measurement of water vapor transmission rate>
The water vapor barrier property of the paper substrate was evaluated in accordance with JIS Z0208:1976 (cup method) B method (temperature 40°C ± 0.5°C, relative humidity 90% ± 2%). The moisture vapor permeability of the laminated body coated with the water vapor barrier composition was measured and evaluated according to the following four grades.
◎: Water vapor permeability is less than 100.0 g/(m ² ·day) ○: Water vapor permeability is 100.0 g/(m ² ·day) or more and less than 150.0 g/(m ² ·day) △: Water vapor permeability is 150.0 g/(m ² ·day) or more and less than 200.0 g/(m ² ·day) ×: Water vapor permeability is 200.0 g/(m ² ·day) or more

<Measurement of adhesion>
A peeling test was carried out on the produced laminate using a cellophane tape, and adhesion was visually evaluated. Judgment criteria are shown below.
⊚ (Practical level): No trace of the coating material.
◯ (Practical level): Less than 5% of the coating agent is torn.
(triangle|delta) (practical level): Tolerance of coating agent is 5% or more and less than 20%.
x (impossible for practical use): Trare of the coating agent is 20% or more.

<Evaluation of water resistance>
The prepared laminate was cut into a size of 17 cm × 1.5 cm, and used as a test piece. Place the friction element on the test piece, apply a load of 200 g from the top of the friction element, and reciprocate the friction element horizontally at a constant speed 100 times. evaluated. Judgment criteria are shown below.
⊚ (Practical level): No tearing of the paper base material after 100 reciprocating motions.
○ (Practical level): The paper base material is torn by reciprocating motion of 75 times or more and less than 100 times.
(triangle|delta) (practical level): A paper base material is torn by reciprocating motion 50 times or more and less than 75 times.
x (practical impractical): The paper substrate is torn by reciprocating motion less than 50 times.

<Examples 67 to 99, Comparative Example 2>
As shown in Table 2, the barrier composition was prepared and the paper substrate was prepared in the same manner as in Example 66, except that the raw material type and blending amount of the water vapor barrier composition, and the type of base material of the barrier laminate were changed. A barrier laminate was prepared, and the water vapor barrier properties, adhesion and water resistance were evaluated. Table 2 shows the results.

Claims (2)

A steam barrier composition comprising a styrenic thermoplastic resin (A) (except when it is a synthetic resin emulsion), a hydrocarbon wax (B) and a solvent (C),
The content of the styrene-based thermoplastic resin (A) is 25 to 95% by mass based on 100% by mass of the solid content of the water vapor barrier composition,
The content of the hydrocarbon wax (B) is 5 to 80% by mass based on 100% by mass of the solid content of the steam barrier composition,
The solvent (C) is an organic solvent (C1) having a Hansen solubility parameter (HSP value) dispersion force term δd of 14 or more and a dipole force term δp of 3 or less. Contains 50 to 100% by mass,
The styrene-based thermoplastic resin (A) is a styrene-isoprene-styrene block copolymer (SIS), a styrene-isobutylene-styrene (SIBS), a hydrogenated styrene-ethylene-propylene-styrene block copolymer (SEPS ), styrene-butylene-styrene block copolymer (SBS), hydrogenated styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-butadiene-isoprene-styrene block copolymer (SBIS), styrene Selected from the group consisting of hydrogenated butadiene-isoprene-styrene block copolymer (SEEPS), or styrene-butadiene copolymer (SB) and their acid modified products, acid anhydride modified products, and amine modified products A water vapor barrier composition comprising one or more of: The hydrocarbon wax (B) has a melting point of 30° C. to 80° C., and contains 80% by mass or more of the hydrocarbon wax (b1) having a linear structure without branches in the hydrocarbon wax (B). The water vapor barrier composition according to claim 1, characterized by: