JPWO2020203346A1 - Compositions for overcoating and adhesives for paper, and coatings using the compositions, water and oil resistant paper laminates, paper straws and paper tableware. - Google Patents

Abstract

The present invention comprises an emulsion containing a resin containing a styrene-acrylic copolymer of styrene, α-methylstyrene and (meth) acrylate, and having a minimum film-forming temperature in the range of −30 ° C. to 30 ° C., and an aqueous medium. The present invention relates to a composition for overcoating and an adhesive for paper, which is characterized by containing the composition, and a coated paper having a resin layer of the composition, water and oil resistant paper, and a laminate such as a paper cup and a paper straw. The present invention has both a function as an adhesive for adhering a paper base material and a paper base material or a plastic film, and a water resistance and oil resistance function desired for an overcoat agent on the surface of the paper base material. It can be recycled without sorting when paper is recycled. Therefore, the overcoating and adhesive compositions of the present invention are useful as a substitute for polyethylene in paper containers and the like.

Description

The present invention relates to a composition for overcoating and an adhesive for paper, which imparts water resistance, oil resistance and oil repellency to paper and further has an adhesive function.

Packaging materials for fast foods such as donuts and hamburgers and cooked foods such as prepared foods need to be water and oil resistant so that the water and oil in the contents do not soak into them. Appropriate moisture permeability is required so that the water vapor generated does not damage the contents and spoil the flavor. As a method of imparting such a function to paper as a packaging material, a method of coating a composition using a fluorine-based compound such as an acrylate or a phosphoric acid ester of a perfluorinated hydrocarbon has been conventionally performed. However, it has been pointed out that in the fluorine-based composition, when heated, the fluorine-based compound existing in the paper is thermally decomposed to generate "persistent" fluorine-based hydrocarbon in the natural world, and problems such as environmental pollution are pointed out.

On the other hand, for example, in Patent Document 1, an oil-resistant paper having excellent oil resistance and air permeability is produced by providing a coating layer of cellulose nanofibers having a carboxyl group on a paper base material. However, since the cellulose nanofibers obtained by the production method of Patent Document 1 have a salt-type carboxyl group on the surface of the crystalline cellulose nanofibers, they are easily swollen and disintegrated by water. Many prepared foods and fast foods contain more water than oil, and the water in the contents may cause the cellulose nanofiber coating layer to collapse, leading to contamination of the contents and penetration of water and oil. is there. Therefore, there is a demand for a highly safe coating agent having water resistance and oil resistance.

Furthermore, in recent years, the problem of marine plastic waste such as microplastics has been highlighted, and as one of the materials with functions such as "reusable" and "biodegradable", it is a renewable resource. There is increasing interest in "paper" made from a certain "wood".

Paper cups, which are one of the widely used paper containers for foods, are made of paper, but polyethylene film, which reduces recycling efficiency, is used as a part of the raw material. A normal paper cup is obtained by sticking a polyethylene film, a polypropylene film, or the like obtained by extruding a polyethylene resin, a polypropylene resin, or the like melted by heat into a film shape to a paper substrate. When molding a paper cup, the polyethylene film acts as an adhesive by heat melting under indirect heating such as a burner or hot air, and since the polyethylene film exists inside the paper cup, the paper base material does not come into direct contact with the contents and is waterproof. Gender and strength are given.
However, the bonded polyethylene film does not dissolve in the alkaline solution used in the paper recycling process at the time of paper recycling, so it must be physically removed, which leads to a decrease in recycling efficiency. In addition, marine pollution caused by the outflow of plastic waste into the ocean has become a global problem. The target of the Sustainable Development Goals (SDGs) is "By 2025, prevent and significantly reduce all types of marine pollution, including marine debris and eutrophication, especially pollution from land activities." The reduction of plastic waste has become an important theme worldwide, as it was raised and it was agreed to strengthen efforts at the summit (summit of major countries). Therefore, there is a need for a polyethylene film substitute that can be applied to these applications and does not reduce the paper recycling efficiency. There is also a demand for paper containers that do not use plastic films.

With regard to paper straws, the movement to abolish the use of plastic straws is rapidly spreading all over the world, triggered by the discovery of a sea turtle with a straw stuck in its nose in 2015 off the coast of Costa Rica in South America. Attention is increasing, with major US hamburger chain stores gradually discontinuing the use of plastic straws in some parts of the European market and planning to introduce paper straws instead.

In the spring of 2018, the British government also announced that it would aim to ban the sale of disposable plastic straws, and at the same time, the European Union (EU) proposed a ban on plastic straws. In addition, the Indian government has announced a policy to ban disposable plastic products by 2022, and the spread to the Asian region is becoming a reality.

Under these circumstances, the movement to switch to paper straws is gradually accelerating in some food service industries in Japan as well.

On the other hand, paper straws are made by laminating two or more sheets of thin paper.
Smoothness when bonded and water resistance associated with water supply when using straws are required, and paper straws using conventionally used polyvinyl alcohol-based adhesives and paper laminates using starch-based adhesives. In reality, the water resistance is particularly insufficient, and the strength of plastic straws cannot be maintained.

On the other hand, for example, in Patent Document 2, for the purpose of improving the adhesiveness with paper, an invention of an aqueous adhesive for paper in which an aqueous dispersion composed of a specific polyolefin resin and an organic amine compound are blended in a specific ratio has been made. However, it cannot be said that it is sufficient in terms of smoothness and water resistance when bonded, and it is insufficient in strength as a laminate for paper tableware.

Japanese Unexamined Patent Publication No. 2011-74535 Japanese Unexamined Patent Publication No. 2003-213233

An object to be solved by the present invention is to provide an overcoating composition for paper that does not contain a fluorine-based compound and imparts water resistance, oil resistance and oil repellency to paper only by coating. Further, the problem to be solved by the present invention is an adhesive for adhering a paper base material to a paper base material or a plastic film, which is desired as a substitute for a paper container such as a paper cup or a polyethylene film used for a paper straw. For overcoating and adhesives for paper, which has both the function as a paper base material and the functions of water resistance and oil resistance desired for the overcoating agent on the surface of the paper base material, and can be recycled without sorting at the time of paper recycling. It is an object of the present invention to provide a composition, a coated product using the composition, a water- and oil-resistant paper laminate, a paper straw, and a paper tableware.

That is, the present invention contains an emulsion containing a styrene-acrylic copolymer of styrene, α-methylstyrene and (meth) acrylate, and having a minimum film-forming temperature in the range of −30 ° C. to 30 ° C., and an aqueous medium. The present invention relates to a composition for overcoating for paper and for an adhesive.

Since the composition for paper overcoating and the adhesive of the present invention does not contain a fluorine-based compound, "persistent" fluorine-based hydrocarbons are not generated even when heated. Further, since good water resistance, oil resistance, and oil repellency can be given to paper only by coating, the coated product obtained by applying the composition for overcoating for paper and the adhesive for paper of the present invention to paper is a food product. Can be safely used for packaging materials, containers, straws, etc. Further, since the composition for overcoating for paper and the composition for adhesive of the present invention also has a function as an adhesive, paper is desired as a substitute for a paper container such as a paper cup or a polyethylene film used for a paper straw. It can have both a function as an adhesive for adhering a base material to a paper base material or a plastic film and a water resistance and oil resistance function desired for an overcoat agent on the surface of the paper base material, and also has paper. It can be recycled without sorting at the time of recycling. Therefore, the overcoating and adhesive compositions of the present invention are useful as a substitute for polyethylene in paper containers and the like.

(Emulsion)
The emulsion used in the present invention contains a resin containing at least a styrene-acrylic copolymer of styrene, α-methylstyrene and (meth) acrylate, and the minimum film-forming temperature is in the range of −30 ° C. to 30 ° C.

The overcoating composition for paper using the emulsion of the present invention has excellent water resistance and oil resistance because it has a dense film-forming property without defects such as pinholes. Further, since the emulsion of the present invention also has adhesiveness, it can be used as an adhesive composition for adhering paper to paper or paper to film.
(Styrene-acrylic copolymer of styrene, α-methylstyrene and (meth) acrylate)
The styrene-acrylic copolymer (hereinafter sometimes referred to as styrene-acrylic copolymer (A)) of styrene, α-methylstyrene and (meth) acrylate used in the present invention is styrene, α-methylstyrene and (meth) acrylate. It is a copolymer with.

In the present invention, (meth) acrylate represents a general term for acrylate and methacrylate, and (meth) acrylic acid represents a general term for acrylic acid and methacrylic acid.

In the present invention, α-methylstyrene represents any or a mixture of o-methylstyrene, m-methylstyrene, and p-methylstyrene. Since the composition of the present invention contains the styrene-acrylic copolymer (A), the heat resistance is improved.

In addition, styrene derivatives other than the styrene and the α-methylstyrene (p-dimethylsilylstyxystyrene, p-tert-butyldimethylsiloxystyrene, p-tert-butylstyrene), vinylnaphthalene, vinylanthracene, 1,1-diphenyl. Ethylene et al. May be partially used as long as the scope of the present invention is not impaired.

The (meth) acrylate is not particularly limited, and for example, methyl (meth) acrylate, ethyl (meth) acrylate, iso-propyl (meth) acrylate, allyl (meth) acrylate, n- (meth) acrylate. Butyl, iso-butyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, n-amyl (meth) acrylate, iso-amyl (meth) acrylate, (meth) N-hexyl acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-lauryl (meth) acrylate, n-tridecyl (meth) acrylate, n-stearyl (meth) acrylate , (Meta) phenyl acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, 4-tert-butylcyclohexyl (meth) acrylate, isobornyl (meth) acrylate, tricyclodecanyl (meth) acrylate , (Meta) dicyclopentadienyl acrylate, (meth) adamantyl acrylate, (meth) glycidyl acrylate, tetrahydrofurfuryl (meth) acrylate, 2-methoxyethyl (meth) acrylate, (meth) acrylate 2-ethoxyethyl, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, trifluoroethyl methacrylate, tetrafluoropropyl methacrylate, pentafluoropropyl methacrylate, octafluoropentyl methacrylate, pentadeca methacrylate Fluorooctyl, heptadecafluorodecyl methacrylate, N, N-dimethyl (meth) acrylamide, acryloylmorpholine, (meth) acrylonitrile, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, polyethylene glycol-polypropylene glycol (meth) Acrylate, polyethylene glycol-polybutylene glycol (meth) acrylate, polypropylene glycol-polybutylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, ethoxypolyethylene glycol (meth) acrylate, butoxypolyethylene glycol (meth) acrylate, octoxy Polyethylene glycol (meth) acrylate, lauroxy polyethylene glycol (meth) acrylate, stearoxy polyethylene glycol (meth) acrylic General purpose (meth) such as rate, polyalkylene oxide group-containing (meth) acrylic monomer such as phenoxypolyethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, octoxypolyethylene glycol-polypropylene glycol (meth) acrylate. Acrylate can be used. Among them, a homopolymer having an acrylate is preferable because it exhibits a lower glass transition temperature, and an acrylate having an alkyl group having 1 to 20 carbon atoms is preferably used as a main component, and an alkyl group having 1 to 12 carbon atoms is used as a main component. It is preferable to use the acrylate as the main component. Examples of such an acrylate having an alkyl group having 1 to 12 carbon atoms include methyl acrylate, ethyl acrylate, iso-propyl acrylate, allyl acrylate, n-butyl acrylate, and iso-butyl acrylate. Meta) sec-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, iso-amyl acrylate, n-hexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, n (meth) acrylate -Lauryl etc. can be mentioned. The (meth) acrylate used as a constituent component of the styrene-acrylic copolymer (A) of the present invention may be one type or two or more types, but two or more types of (meth) acrylates should be used. Of these, it is preferable to use two or more types of acrylates having an alkyl group having 1 to 12 carbon atoms as the main component.

The emulsion used in the present invention preferably further contains a copolymer of (meth) acrylic acid and (meth) acrylate. The copolymer of (meth) acrylic acid and (meth) acrylate is a copolymer of (meth) acrylic acid and the (meth) acrylate (hereinafter, may be referred to as acrylic copolymer (B)). .. The (meth) acrylate is not particularly limited, but among them, an acrylate having an alkyl group having 1 to 20 carbon atoms is preferable, and a homopolymer having an acrylate exhibits a lower glass transition temperature, so that carbon is preferable. It is preferable to use an acrylate having an alkyl group having 1 to 20 atoms as a main component, and it is preferable to use an acrylate having an alkyl group having 1 to 12 carbon atoms as a main component. Examples of such an acrylate having an alkyl group having 1 to 12 carbon atoms include methyl acrylate, ethyl acrylate, iso-propyl acrylate, allyl acrylate, n-butyl acrylate, and iso-butyl acrylate. Meta) sec-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, iso-amyl acrylate, n-hexyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, n (meth) acrylate -Lauryl etc. can be mentioned.

The emulsion used in the present invention preferably contains the styrene-acrylic copolymer (A) and the acrylic copolymer (B), but this is a known aqueous medium such as emulsion polymerization or transfer emulsion. The emulsion of the styrene-acrylic copolymer (A) polymerized by the polymerization method used and the emulsion of the acrylic copolymer (B) polymerized by a polymerization method using a known aqueous medium such as emulsion polymerization or transfer emulsion. May be an emulsion in which the above-mentioned styrene-acrylic copolymer (A) and the above-mentioned acrylic copolymer (B) are appropriately mixed, or an emulsion of a resin in which the styrene-acrylic copolymer (A) and the acrylic copolymer (B) form a core-shell structure. The "resin containing the styrene-acrylic copolymer (A)" may be a resin made of the styrene-acrylic copolymer (A), or the styrene-acrylic copolymer (A) and the acrylic copolymer weight. The coalescence (B) may be a resin that forms a core-shell structure.
(Emulsion manufacturing method)
In the present invention, the emulsion can be obtained by polymerization by a polymerization method using a known aqueous medium such as known emulsion polymerization or transfer emulsification without particular limitation. Further, there are various expressions such as emulsion, dispersion, suspension, etc. in the form in which the polymer is dispersed in an aqueous medium, but in the present invention, it is unified as an emulsion.

For example, a monomer mixture is supplied in an aqueous medium and the monomer mixture is polymerized in the presence of an initiator to polymerize an emulsion.

In the case of an emulsion in which the emulsion of the styrene-acrylic copolymer (A) and the emulsion of the acrylic copolymer (B) are appropriately mixed, it is obtained by mixing an emulsion obtained by polymerizing each monomer mixture.

Further, in the case of an emulsion forming a core-shell structure, a step (1) of supplying a monomer mixture forming a core polymer and polymerizing the monomer mixture in the presence of an initiator to form a core polymer, and a shell polymer. It is obtained by the step (2) of supplying the monomer mixture forming the above to the core polymer of the step (1) and polymerizing the monomer mixture in the presence of an initiator to form a shell on the core polymer. Further, a step (i) of supplying a monomer mixture forming a shell polymer and polymerizing the monomer mixture to form a shell polymer in the presence of an initiator, and a step (i) of forming a core polymer. It is obtained by the step (ii) of feeding the shell polymer of the above and polymerizing this monomer mixture in the presence of an initiator to form a shell on the core polymer.

The initiator is not particularly limited, and a peroxide, a persulfate, an azo compound, a redox type, or a mixture thereof used in an emulsion polymerization method or the like may be used. Peroxides include, for example, hydrogen peroxide, ammonium peroxide, sodium peroxide, or potassium peroxide, t-butyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, and benzene peroxide. Examples of the persulfate include ammonium persulfate, sodium persulfate, and potassium persulfate. Examples of the azo compound include 2,2-azobisisobutyronitrile and 4,4'-(4-cyanovaleric acid). The redox system is composed of an oxidizing agent and a reducing agent, and the oxidizing agent is, for example, one of the above-mentioned peroxides, persulfates, or azo compounds, or sodium chloride or potassium chloride, or sodium bromide or Examples include potassium bromide. Examples of the reducing agent include ascorbic acid, glucose, ammonium, sodium hydrogensulfate or potassium hydrogensulfate, sodium hydrogensulfite or potassium hydrogensulfite, sodium thiosulfate or potassium thiosulfate, or sodium sulfide or potassium sulfide, or iron (II). ) Ammonium sulfate can be mentioned.
Of these, persulfate, more preferably ammonium persulfate, is preferable.

The polymerization of the monomer mixture can be carried out, for example, in the presence of additives such as surfactants, chain transfer agents and chelating agents, for example in the presence of surfactants and chain transfer agents. These additives may be added in advance to the aqueous medium used in the step (1), or may be mixed with the monomer mixture supplied in the step (1) or the step (2).

The surfactant is not particularly limited, and examples thereof include disodium dodecyldiphenyl oxide and disulfonate. The chain transfer agent is also not particularly limited, and examples thereof include α-methylstyrene dimer, thioglycolic acid, sodium hydrogen phosphate, 2-mercaptoethanol, N-dodecyl mercaptan, and t-dodecyl mercaptan. The chelating agent is not particularly limited, and examples thereof include ethylenediaminetetraacetic acid.

When forming a core-shell structure, in order to enhance stability in an aqueous medium, it is preferable that the acrylic copolymer (B) having an acidic group becomes a shell, but all the acrylic copolymers during synthesis. There is no problem even if the emulsion has a structure in which (B) is not a shell and the styrene-acrylic copolymer (A) is partially a shell.

When neutralization is required, bases such as ammonia, triethylamine, aminomethylpropanol, monoethanolamine, diethylaminoethanol, sodium hydroxide and potassium hydroxide can be used as the neutralizing agent.
(Minimum film formation temperature)
The minimum film-forming temperature of the emulsion is in the range of −30 ° C. to 30 ° C.
In the present invention, the minimum film-forming temperature is the minimum temperature required for a continuous film to be formed when the water content of the synthetic rubber latex evaporates and dries, and is obtained by the temperature gradient plate method. Among them, the range of −10 to 25 ° C. is preferable, and the range of −5 to 20 ° C. is more preferable.

The glass transition temperature of the emulsion (hereinafter sometimes referred to as Tg) is preferably in the range of -40 ° C to 30 ° C, particularly preferably in the range of 35 to 25 ° C, and in the range of -30 to 23 ° C. Is more preferable.
In the present invention, the glass transition temperature is obtained by measurement with a differential scanning calorimeter.

The acid value of the emulsion is preferably in the range of 30 to 80 mgKOH / g, particularly preferably in the range of 40 to 75 mgKOH / g, and more preferably in the range of 50 to 70 mgKOH / g.

In the present invention, the acid value is obtained by a measuring method based on the JIS test method K0070-1992.
(Other resins)
The overcoating composition for paper of the present invention may contain a resin other than the styrene-acrylic copolymer (A) and the acrylic copolymer (B).

For example, when the overcoating composition for paper of the present invention is referred to as a resin having a glass transition temperature higher than the glass transition temperature of the resin containing the styrene-acrylic copolymer (A) (hereinafter referred to as a resin (C) having a high glass transition temperature). There is), it is preferable to further contain. By containing the resin (C) having a high glass transition temperature, it is possible to improve the blocking resistance and the slipperiness when the coated paper coated with the coating composition of the present invention is laminated. it can. The glass transition temperature of the resin (C) is preferably 20 ° C. or higher, more preferably 30 ° C. or higher, higher than the glass transition temperature of the resin containing the styrene-acrylic copolymer (A). The glass transition temperature of the resin (C) is preferably in the range of 0 ° C. to 85 ° C. so as not to impair the effect of the coating composition of the present invention. Specifically, the glass transition temperature of the resin containing the styrene-acrylic copolymer (A) is preferably in the range of −40 ° C. to 0 ° C., whereas the resin (C) is preferably in the range of 0 ° C. to 40 ° C. ..

The material of the resin (C) having a high glass transition temperature is not particularly limited, but it must be a styrene-acrylic copolymer so as not to impair the properties such as oil resistance and heat resistance of the coating composition of the present invention. Is preferable, and it is more preferable that the material is the same as the resin containing the styrene-acrylic copolymer (A). The content of the resin (C) can be appropriately adjusted according to the desired blocking resistance and stacking property, but the weight ratio of the resin containing the styrene-acrylic copolymer (A) to the resin (C) (styrene acrylic). The copolymer (A) / resin (C)) is preferably 90/10 to 20/80, and preferably 80/20 to 30/70.

The emulsion used in the present invention containing the resin (C) having a high glass transition temperature includes, for example, an emulsion containing the resin containing the styrene-acrylic copolymer (A) and known aqueous emulsions such as emulsion polymerization and transfer emulsification. It is obtained by appropriately mixing with an emulsion of the resin (C) polymerized by a polymerization method using a medium.
(Other additives)
The paper overcoating composition of the present invention may also contain silica, alumina, polyethylene wax, defoaming agents, leveling agents, tackifiers, preservatives, antibacterial agents, rust preventives and the like.

By containing wax, the emulsion used in the present invention can improve the slipperiness when the coated paper coated with the coating composition of the present invention is laminated, so that the workability can be improved. Examples of the wax include waxes such as fatty acid amide wax, carnauba wax, polyolefin wax, paraffin wax, Fisher Tropsch wax, mitsuro, microcrystallin wax, polyethylene oxide-wax, and amido wax. These may be used alone or in combination.

Of these, fatty acid amide wax, carnauba wax, Fisher Tropsch wax, polyolefin wax, and paraffin wax are preferably used, and carnauba wax, polyolefin wax, and paraffin wax are particularly preferable.

Specific examples of the fatty acid amide wax include pelargonic acid amide, capric acid amide, undecyl acid amide, lauric acid amide, tridecyl acid amide, myristic acid amide, pentadecyl acid amide, palmitic acid amide, heptadecyl acid amide, and stearic acid amide. , Nonadecanic acid amide, araquinic acid amide, bechenic acid amide, lignoseric acid amide, oleic acid amide, setreic acid amide, linoleic acid amide, linolenic acid amide, mixtures thereof, animal and vegetable fat and oil fatty acid amides and the like.
Specific examples of the carnauba wax include MICROKLEAR 418 (manufactured by Micro Powerers, Inc.), purified carnauba wax No. 1 powder (Nippon Wax Co., Ltd.) and the like.

Specific examples of the olefin wax include polyethylene wax and polypropylene wax, and examples thereof include MPP-635VF (Micro Powerers, Inc.) and MP-620VF XF (Micro Powerers, Inc.).

Specific examples of the paraffin wax include MP-28C, MP-22XF, MP-28C (Micro Powerers, Inc.) and the like.

The total amount of the wax blended is preferably 1.5 to 20% by mass with respect to the total amount of 100% by mass of the solid content in the composition of the present invention. If the total amount of wax is 3% by mass or more with respect to the total amount of 100% solid content in the composition of the present invention, the blocking resistance tends to be maintained, and the total amount of wax is 15% by mass with respect to the total amount of 100% solid content of the aqueous heat sealant. If it is less than%, the heat sealability tends to be maintained.

The melting point of the wax is preferably in the range of 80 ° C. to 130 ° C. from the viewpoint of oil resistance and heat resistance. The wax is directly added to and mixed with the emulsion of the resin containing the styrene-acrylic copolymer (A). It may be dispersed, or a wax dispersion may be prepared and then mixed with an emulsion. As a dispersion method, a known method, for example, a paint shaker, a ball mill, an attritor, a basket mill, a sand mill, a sand grinder, a dyno mill, a dispermat, an SC mill, a spike mill, an agitator mill or the like is used as a dispersion device using a medium. It can be dispersed by an ultrasonic homogenizer, a high-pressure homogenizer, a nanomizer, a resolver, a disper, a high-speed impeller disperser, or the like without using a medium.

When powdered wax is used, it is preferable to knead the meat with a medium or to mix the wax after preparing the wax dispersion in order to uniformly disperse the wax. The kneading method can be carried out by a known method.

When a plurality of types of waxes are used in combination, a plurality of types of waxes may be added at the same time, or may be added separately in a plurality of steps.

In addition, the composition for paper overcoating and adhesive of the present invention is a polymer-based defoaming agent, a silicone-based defoaming agent, in order to prevent the composition from foaming when coated using various coaters. A fluorofoaming agent is preferably used. As these antifoaming agents, both emulsified dispersion type and solubilized type can be used. Of these, polymer-based defoamers are preferable.
The amount of the defoaming agent added is preferably 0.005% by weight to 0.1% by weight based on the total amount of the overcoating composition for paper.

Specific examples of the composition for overcoating and adhesive for paper of the present invention include, for example, a roll coater, a gravure coater, a flexo coater, an air doctor coater, a blade coater, an air knife coater, a squeeze coater, and impregnation. A coater, a transfer coater, a kiss coater, a curtain coater, a cast coater, a spray coater, a die coater, an offset printing machine, a screen printing machine, etc. can be appropriately adopted, and the obtained printed matter is post-processed according to various uses. And used for packaging products such as food.
(Coating process of applying the overcoating composition for paper on a paper substrate)
The paper base material used in the present invention is produced by a known paper machine using natural fibers for papermaking such as wood pulp, but the papermaking conditions are not particularly specified. Examples of natural fibers for papermaking include wood pulp such as coniferous tree pulp and broadleaf tree pulp, non-wood pulp such as Manila hemp pulp, sisal hemp pulp, and flax pulp, and pulp obtained by chemically modifying these pulps. As the type of pulp, chemical pulp, gland pulp, chemigrand pulp, thermomechanical pulp and the like obtained by a sulfate cooking method, an acidic / neutral / alkaline sulfite cooking method, a soda salt cooking method and the like can be used.
Further, various commercially available high-quality papers, coated papers, backing papers, impregnated papers, cardboards, paperboards and the like can also be used.
As a method for applying the dispersion liquid of the present invention on a paper substrate, a comma coater, a roll coater, a reverse roll coater, a direct gravure coater, a reverse gravure coater, an offset gravure coater, a roll kiss coater, a reverse kiss coater, and a kiss Gravure coater, reverse kiss gravure coater, air doctor coater, knife coater, bar coater, wire bar coater, die coater, lip coater, dip coater, blade coater, brush coater, curtain coater, die slot coater, etc. The above coating methods can be used in combination.

Further, a resin layer may be provided on the paper base material by impregnating the paper base material with the composition for overcoating and adhesive of the present invention.

The film thickness of the composition for paper overcoating and adhesive of the present invention at the time of coating depends on the application, but when used for a food paper container, for example, if it is in the range of ^{2 to 10 g / m 2.} The effect of the present invention can be sufficiently obtained. Above all, the range is more preferably 6 to 10 g / m ^2.

The coated product obtained by applying the composition for paper overcoating and adhesive of the present invention to a paper base material has water resistance, oil resistance, and oil repellency, and therefore was used as an overcoating agent for paper. In the case, it can be used as water resistant and / or oil resistant paper. The coated products of the present invention include paper cups, cup noodles, various beverages, desserts such as ice cream, pudding and jelly, snacks such as rice confectionery, potato chips, chocolate confectionery and biscuits, hamburger and hot dock wrapping paper, and pizza. It is widely used for take-out containers such as, hot snack containers such as fried chicken and potatoes, food paper containers such as cups for delicatessen such as natto, and paper straws.
(Manufacturing method of paper container)
As a specific embodiment for producing a paper container using the composition for paper overcoating and adhesive of the present invention, at least a laminate in which a paper base material and a paper base material or a plastic film are adhered, and the paper base is used. A method for producing a paper cup-like paper container using a laminate having the resin layer of the composition for overcoating and adhesive for paper of the present invention on at least one surface of the material will be specifically described. In addition, in this specification, a "laminate body" means a paper and a paper or a paper and a plastic film having a part which overlaps with each other even a part. In the present invention, the present invention is not limited to the specific embodiment, and can be applied to all coatable paper containers.

The paper cup using the laminated body of the present invention is bonded to the body member (1), which is bonded by laminating the bonded surfaces of both ends of the rolled paper base material, and to the lower end of the body member (1). It has a plate-shaped bottom member (2). The paper cup is provided with a resin layer on the inner surface of the container and the bonding surface when the container is assembled, and the composition for paper overcoating and adhesive of the present invention is used for this resin layer.

Both the tubular body member (1) and the plate-shaped bottom member (2) are made by cutting out a paper base material provided with a resin layer into a desired shape.
First, in the paper base material, at least a part of the inner surface (inner side surface of the hump) of the paper container and / or at least a part of the surface to be the bonding surface of the present invention is used for the paper overcoating and the adhesive of the present invention. Apply the composition. As the coating method, the above-mentioned coating method can be appropriately used. After coating, the aqueous solvent on the coated surface is removed with a dryer or the like, and then printing is performed as necessary. The printed surface is often applied to the surface opposite to the coated surface.
Next, in the paper base material provided with the resin layer by coating, the tubular body member (1) is cut out in a fan shape, and the plate-shaped bottom member (2) is cut out in a circular shape. The order of the steps of providing the resin layer on the paper base material and the step of cutting out the paper base material is not particularly limited, and the resin layer may be provided after cutting out the paper base material in a fan shape or a circular shape.

After coating the composition of the present invention on a paper base material, the bonded surfaces at both ends of the tubular body member (1) cut out in a fan shape in a dry state to the extent that the composition has adhesiveness and adhesiveness. Are overlapped and crimped or thermocompression bonded. The method of thermocompression bonding is not particularly limited, but a heat source such as a burner or hot air can be used. The order of heating, laminating, and crimping is not particularly limited, but if the bonded surfaces are superposed on each other and then heated with a heat source while crimping, the coated composition does not dry due to heating, so that the adhesiveness is improved. It is preferable because it can be adhered more firmly without being damaged. The heating temperature at this time is preferably 200 to 450 ° C., and the heat crimping time is preferably 0.5 to 3 seconds.

On the other hand, the bottom member (2) cut out in a circular shape is installed on the inside of the tubular body member so that the surface coated with the composition of the present invention is inside the cup, and then the bottom member and the body. The contact portion with the member is adhered by crimping or thermocompression bonding the resin layers on the bottom member side and the body member side in the same manner as described above. At this time, since the resin layer fills the gap between the bottom member and the body member, water leakage or the like does not occur.

After that, the aqueous solvent of the resin layer on the inner surface of the paper container may be removed by a dryer or the like.
In the production of the paper cup, a paper cup can be obtained by a known process, for example, a method in which the lower end of the bottom side of the body member is folded inward and crimped with a rotating circular mold to finish the bottom of the paper cup. Finally, the portion corresponding to the spout at the upper end of the body member is subjected to a molding process called curling, in which the tool is rolled around the outside of the paper cup as needed.
The paper container of the specific embodiment is mainly a cup-shaped container having a disc-shaped bottom member, but the shape is not limited to this, for example, a rectangular parallelepiped or polygonal bottom member having a rectangular plate shape. Alternatively, it may be a cube-shaped container. Further, if necessary, the container is sealed with a separately manufactured lid material or the like, and for example, when heating in a microwave oven or the like, the lid material is removed or a part of the container is opened and used. May be good.

As described above, a laminate (paper container) in which the paper base material and the paper base material are adhered to each other by the resin layer of the composition of the present invention is obtained, and the paper base material and the paper base material are laminated. A laminate (paper container) having a resin layer for overcoating can be obtained in a portion not provided.

In the above method, the structure in which the resin layer of the composition of the present invention is provided on both the inner surface (inner side surface of the hump) and / or the surface to be the bonding surface of the paper container has been described. The inner surface of the container may be provided with only a resin layer for overcoating, and the bonded surface may be provided with another adhesive material such as a heat sealant for bonding, or the resin of the present invention may be provided only on the bonded surface. The layer may be used as an adhesive.
(Manufacturing method of paper straws)
Next, a method for producing a paper straw using the laminate of the present invention will be specifically described. The paper straw of the present invention has a tubular structure in which at least one end of one or more sheets of paper is laminated and laminated. The paper straw is provided with a resin layer on the surface (inner surface and outer surface) of the straw and the laminated laminated surface, and the composition for overcoating and adhesive for paper of the present invention is used for this resin layer.

The paper straw may be one in which one sheet of paper is rolled into a cylinder and the edges are bonded to each other, or a plurality of tape-shaped sheets of paper are spirally wound and the papers are bonded to each other to form a cylinder. It may be something to do. Hereinafter, a method for manufacturing a spiral straw will be described.

First, a tape-shaped paper base material is prepared, and resin layers of the composition of the present invention are provided on both sides of the paper base material. As a method for forming the resin layer, the above-mentioned coating method or the method by impregnation can be appropriately used. A sheet-shaped paper base material may be prepared, a resin layer of the composition of the present invention may be provided, and then the tape-shaped paper base material may be cut. From the viewpoint of water resistance and strength of the paper straw, it is preferable to use two or three tape-shaped paper base materials as the paper base material, and when a plurality of tape-shaped papers are spirally wound, the straw is used. The type of paper base material can be changed between the paper material located on the inside and the paper material located on the outside. For example, the inner paper material should be relatively thick to impart strength, and the outermost paper material should be relatively thin to smooth the surface, and printing should be done as needed. May be given. The tape width can be appropriately adjusted according to the desired diameter (width) of the straw, and is preferably about 0.5 cm to 2.0 cm, for example.

After coating the composition of the present invention on a paper base material, a tape-shaped paper is spirally wound around a core material in a dry state to the extent that the composition has adhesiveness and adhesiveness. At this time, while overlapping the edges of the previously wound paper, for example, three sheets of tape paper located at the innermost side of the straw, tape paper located at the center, and tape paper located at the surface are wound in sequence to form a tape. The bonded surface of the paper is crimped or thermocompression bonded. As the heat source and heating temperature at the time of thermocompression bonding, the above-mentioned method of paper container can be appropriately used.

After that, the aqueous solvent of the resin layer on the inner surface and the surface of the paper straw is removed by a dryer or the like, and the core material is pulled out to form a straw on a cylinder in which a cavity is formed.
As described above, a laminate (paper straw) in which the paper base material and the paper base material are adhered to each other by the resin layer of the composition of the present invention is obtained, and the paper base material and the paper base material are laminated. A laminate (paper straw) having a resin layer for overcoating can be obtained in a portion not provided.

In the above method, an example in which a paper base material and a paper base material are laminated has been described, but the paper base material and the plastic film may be bonded to each other using the composition of the present invention, or the surface may be coated. For example, in a paper straw, a laminated body in which a tape-shaped paper and a tape-shaped film are laminated may be used as a straw.

Hereinafter, the present invention will be described in detail based on examples, but the technical scope of the present invention is not limited to these embodiments.

The minimum film-forming temperature was measured using a film-forming temperature tester (Imoto Seisakusho Co., Ltd.) by the temperature gradient plate method.

The glass transition temperature (Tg) is measured using a differential scanning calorimeter (“DSC Q100” manufactured by TA Instruments Co., Ltd.) in a nitrogen atmosphere, using a cooling device, a temperature range of -80 to 450 ° C, and a temperature rise temperature of 10. It was performed by scanning under the condition of ° C./min.

The acid value was measured according to the JIS test method K0070-1992. It was determined by dissolving 0.5 g of the polymer in a tetrahydrofuran (THF) solvent and titrating with a 0.1 M potassium hydroxide alcohol solution using phenolphthalein as an indicator.

(Manufacturing Example 1)
<Synthesis of acrylic emulsion>
First, the core / shell type acrylic emulsion used in Example 1 was synthesized. In the synthesis example, "part" represents "part by weight" and "%" represents "% by weight".
(Synthesis Example 1)
100 parts of isopropyl alcohol was charged into a nitrogen gas-substituted four-necked flask, the temperature was raised to 80 to 82 ° C., and then 1 part of myristyl acrylate, 30 parts of styrene, 10 parts of acrylic acid, and methyl methacrylate 5 were charged in a dropping funnel. A mixture of 1 part and 1 part of benzoyl peroxide was added dropwise over 2 hours. After completion of the dropping, 0.5 part of benzoyl peroxide was added, and the mixture was further reacted for 2 hours. The temperature was lowered to 40 ° C., and dimethylethanolamine and ion-exchanged water were added. Then, the temperature of the reaction flask was raised to 80 to 82 ° C., stripping was performed, and finally a water-soluble resin having a solid content of 30% was obtained.
To the water-soluble resin obtained above, 10 parts of ion-exchanged water was charged into a reaction flask, the temperature was raised to 80 ° C. to 82 ° C., 2 parts of potassium persulfate was added, and 15 parts of styrene and 5 parts of α-methylstyrene were added. , A mixture of 24 parts of 2-ethylhexyl acrylate and 10 parts of butyl acrylate was added dropwise over 2 hours. After completion of the dropping, 0.2 part of potassium persulfate was added and reacted for 2 hours. The solid content of the acrylic emulsion (resin 1) thus obtained was 40%, the minimum film forming temperature was 1 ° C., the glass transition point was −27 ° C., and the acid value of the solid content was 64 mgKOH / g. ..
(Example 1)
85 parts of the acrylic emulsion (resin 1), 0.03 part of the polymer defoamer, and 14.97 parts of ion-exchanged water, a total of 100 parts, are sufficiently stirred at 25 ° C. for 15 minutes with a disper to cover the paper. A coating composition was prepared.

(Example 2)
A commercially available acrylic emulsion having "styrene-acrylic copolymer (styrene-acrylic copolymer (A)) of styrene, α-methylstyrene, and (meth) acrylate" instead of the acrylic emulsion (resin 1) of Example 1. An overcoating composition for paper was prepared in the same procedure as in Example 1 except that 85 parts of A was used.

The minimum film-forming temperature of the commercially available acrylic emulsion A was 18 ° C., the glass transition point was 21 ° C., and the acid value of the solid content was 55 mgKOH / g.
(Example 3)
A commercially available acrylic emulsion having "styrene-acrylic copolymer (styrene-acrylic copolymer (A)) of styrene, α-methylstyrene, and (meth) acrylate" instead of the acrylic emulsion (resin 1) of Example 1. An overcoating composition for paper was prepared in the same procedure as in Example 1 except that 85 parts of B was used.

The minimum film-forming temperature of the commercially available acrylic emulsion B was 1 ° C., the glass transition point was −9 ° C., and the acid value of the solid content was 61 mgKOH / g.

(Example 4)
A commercially available acrylic emulsion having "styrene-acrylic copolymer (styrene-acrylic copolymer (A)) of styrene, α-methylstyrene, and (meth) acrylate" instead of the acrylic emulsion (resin 1) of Example 1. An overcoating composition for paper was prepared in the same procedure as in Example 1 except that 85 parts of D was used.

The minimum film-forming temperature of the commercially available acrylic emulsion D was 6 ° C., the glass transition point was 8 ° C., and the acid value of the solid content was 55 mgKOH / g.

(Example 5)
An acrylic emulsion (86 parts in total) in which 64 parts of the acrylic emulsion (resin 1) of Example 1 and 22 parts of the acrylic emulsion A of Example 2 were mixed was used, and the ion-exchanged water was 13.97 parts. , An overcoating composition for paper was prepared in the same procedure as in Example 1.

(Example 6)
Acrylic emulsion (86 parts in total), which is a mixture of 43 parts of the acrylic emulsion (resin 1) of Example 1 and 43 parts of acrylic emulsion A of Example 2, was used. A coating composition was prepared.

(Example 7)
Over paper using the same procedure as in Example 5 except that 21 parts of the acrylic emulsion (resin 1) of Example 1 and 65 parts of the acrylic emulsion A of Example 2 were mixed (86 parts in total) were used. A coating composition was prepared.

(Example 8)
In the acrylic emulsion of Example 7, 1.2 parts of carnauba wax (MICROKLEAR 418: Micro Powerers, Inc.) was added, and the overcoating composition for paper containing 12.77 parts of ion-exchanged water was uniformly dispersed. An overcoating composition for paper of Example 8 was prepared.

(Example 9)
Example 9 was uniformly dispersed by the same procedure as in Example 8 except that 1.2 parts of polyethylene wax (MPP-635VF: Micro Papers, Inc.) was added instead of the carnauba wax of Example 8. An overcoating composition for paper was prepared.

(Example 10)
Paper of Example 10 uniformly dispersed by the same procedure as in Example 8 except that 1.2 parts of paraffin wax (MP-28C: Micro Powders, Inc.) was added instead of the carnauba wax of Example 8. An overcoating composition for use was prepared.

(Comparative Example 1)
An overcoating composition for paper was prepared in the same procedure as in Example 1 except that 85 parts of a commercially available acrylic emulsion C was used instead of the acrylic emulsion (resin 1) of Example 1.

The minimum film-forming temperature of the commercially available acrylic emulsion C was 101 ° C., the glass transition point was 99 ° C., and the acid value of the solid content was 49 mgKOH / g.
The overcoating compositions for paper prepared in Examples 1 to 10 and Comparative Example 1 were used on pure white paper (manufactured by Nippon Paper Industries Co., Ltd.) ^{having a basis weight of 40 g / m 2 using a wire bar to increase the thickness of the film.} The coating was applied so as to be 10 g / m ² , and dried at 150 ° C. for 20 seconds using a dryer to prepare coated papers for evaluation.

(Oil resistance evaluation)
The vegetable oil is collected in a dropper, and 0.1 ml is added dropwise to a test piece of coated paper for evaluation.
After dropping the salad oil, after 2 hours at 60 ° C. and 2 hours at 120 ° C., the salad oil is wiped off, and the front surface and the back surface are visually evaluated according to the following evaluation criteria.

◯: There is no trace of dripping on the front surface, and there is no penetration into the back surface.
Δ: There are traces of dripping on the front surface, but there is no penetration into the back surface.
X: There are traces of dripping on the front surface, and there is penetration into the back surface.

(Water resistance evaluation)
Tap water is collected in a dropper, and 0.1 ml is added dropwise to a coated paper test piece for evaluation.
After the tap water is dropped and 30 minutes have passed at 25 ° C., the tap water is wiped off, and the front surface and the back surface are visually evaluated according to the following evaluation criteria.
◯: There is no trace of dripping on the front surface, no swelling due to water, and no penetration into the back surface.
Δ: There are traces of dripping on the front surface, but there is no penetration into the back surface.
X: There are traces of dripping on the front surface and swelling due to water, and there is penetration into the back surface.

(Oil repellency evaluation)
Using the prepared coated paper, Japan TAPPI pulp and paper test method No. The oil repellency was evaluated using the 41 kit method. At the time of evaluation, a case where the oil repellency was 5 or more was passed, and a case where the oil repellency was less than 4 was rejected. The oil repellency of 12 is the maximum and most preferable.
(Blocking resistance)
The coated surface and the coated surface of the prepared coated paper are overlapped so as to be in contact with each other, ^{a load of 10 kgf / cm 2} is applied, and the paper is allowed to elapse in an environment of 40 ° C. for 48 hours. The condition was visually evaluated in the following four stages.
(Evaluation criteria)
⊚: No blocking is seen.
〇: Slight blocking is seen partially.
Δ: Blocking is partially seen.
X: Blocking is seen over the entire surface.

(Sliding angle)
The coated surface of the produced coated paper was superposed so as to be in contact with each other, and the inclination angle at which the coated paper started to slide was measured as the sliding angle by the inclination method. The sliding angle was measured using a sliding angle inclination measuring device (manufactured by HEIDON).

In the same manner, the slip angle was measured by superimposing the coated surface and the non-coated surface (back surface) of the prepared coated paper so as to be in contact with each other.

The smaller the value of the sliding angle, the better the slipperiness. Therefore, it becomes easier to take out the coated papers one by one from the laminated coated papers, and the workability is improved.

Tables 1 and 2 show the compositions of the overcoating compositions for each paper of Examples 1 to 10 and Comparative Example 1, and the evaluation results of the coated paper using the coating composition.

The coated paper using the overcoating composition for paper of the present invention has excellent water resistance, oil resistance and oil repellency.

Further, in Examples 5 to 8 in which resins having different glass transition points were mixed and used, the blocking property was improved and the sliding angle was lowered, and in Examples 8 to 10 in which wax was further added, the sliding angle was further lowered. The result was.

[Preparation of paper laminate [I]]
(Example 11)
^{Using the overcoating composition for paper prepared in Example 1 as the adhesive S, a coating amount of 3.0 g / m 2} was applied to a paper straw base paper (with a basis weight of 90 g / m manufactured by Paper Tech Co., Ltd.) with a bar coater. After coating and drying at 80 ° C for -1 minute, two straw base papers are laminated, and then the bonded one side is coated again with a bar coater at a coating amount of 3.0 g / m ² and then applied at 80 ° C-1. It was dried for 1 minute to form a paper laminate in which three straw base papers were laminated, and further cured (aged) at 40 ° C. for 24 hours.
(Examples 12 and 13 and Comparative Example 2)
The paper overcoat compositions prepared in Examples 2 and 3 and Comparative Example 1 were used as adhesives T, U, and V, respectively, and three straw base papers were laminated in the same procedure as in Example 11 to prepare a laminated paper. Then, the curing (aging) was carried out at 40 ° C. for 24 hours in the same manner.

[Preparation of paper / film laminate [II]]
(Example 14)
The overcoating composition for paper prepared in Example 1 was applied as an adhesive S to the corona-treated surface of a PET film (film thickness: 12 μm) with a bar coater at a coating amount of 3.0 g / m ² at 80 ° C. for 1 minute. After drying in, it was bonded to a cup base paper (manufactured by Nippon Paper Industries, Ltd.), and then cured (aged) at 40 ° C. for 3 days.
(Examples 15 and 16 and Comparative Example 3)
The overcoating compositions for paper prepared in Adjustment Examples 2 and 3 and Comparative Example 1 were used as adhesives T, U, and V, respectively, and a PET film (film thickness: 12 μm) and a cup base paper were used in the same procedure as in Example 14. After the bonding, the same curing (aging) was performed at 40 ° C. for 3 days.

[Evaluation]
The laminates of Examples 11-16 and Comparative Examples 2-3 were evaluated as follows, and the results are summarized in Tables 3 and 4.
(Water resistance 1: Paper laminate [I] and paper / film laminate [II])
The prepared paper laminate [I] and paper / film laminate [II] were cut into strips each having a width of 15 mm, and the laminates were immersed in tap water at 25 ° C. for 6 hours. It was evaluated visually in three stages of.
◯: No change in appearance is seen.
Δ: Slight peeling is observed between papers or between papers / films.
X: Peeling between papers or between papers / films is observed.
(Water resistance 2: Paper laminate [I])
With respect to the prepared paper laminate [I], the wet tensile strength of the paper base material was measured according to JIS P8135, and the water resistance was evaluated.
◯: 2.0 kN / m or more.
Δ: 1.5 or more and less than 2.0 kN / m.
X: Less than 1.5 kN / m.
(Adhesion: Paper / film laminate [II])
Cellophane tape (TF-12 manufactured by Nichiban Co., Ltd.) is pressure-bonded to the film surface of the produced paper / film laminate [II], and the degree of film peeling when the tape is peeled off at once is visually evaluated in the following three stages. did.
◯: No change in appearance is seen.
Δ: Floating was observed in a part of the film.
X: The film has peeled off from the paper.

The evaluation results of the laminated bodies of Examples 11 to 16 and Comparative Examples 2 and 3 are shown in Tables 3 and 4.

The paper laminate of the present invention has excellent water resistance and adhesion.

Claims (13)

It contains a resin containing a styrene-acrylic copolymer of styrene, α-methylstyrene, and (meth) acrylate, and contains an emulsion having a minimum film-forming temperature in the range of −30 ° C. to 30 ° C. and an aqueous medium. A characteristic composition for overcoating and adhesives for paper. The composition for paper overcoating and adhesive according to claim 1, wherein the glass transition temperature of the emulsion is in the range of −40 ° C. to 30 ° C. and the acid value is in the range of 30 to 80 mgKOH / g. The composition for overcoating and adhesive for paper according to claim 1 or 2, further containing a copolymer of (meth) acrylic acid and (meth) acrylate. The paper overcoat according to claim 3, wherein the styrene-acrylic copolymer of styrene, α-methylstyrene and (meth) acrylate, and the copolymer of (meth) acrylic acid and (meth) acrylate form a core-shell structure. Compositions for coatings and adhesives. The composition for paper overcoating and adhesive according to any one of claims 2 to 4, further comprising a resin having a glass transition temperature higher than the glass transition temperature of the resin. The composition for paper overcoating and adhesive according to any one of claims 1 to 5, wherein the composition further contains wax. A coated paper having a resin layer of the composition for overcoating for paper and the composition for adhesive according to any one of claims 1 to 6 on a paper base material. A water- and oil-resistant paper having a resin layer of the composition for overcoating and adhesive according to any one of claims 1 to 6 on a paper base material. At least a laminate in which a paper base material and a paper base material or a plastic film are adhered to each other.
A laminate characterized by having a resin layer of the composition for overcoating for paper and the composition for adhesive according to any one of claims 1 to 6 on at least one surface of a paper base material. The laminate according to claim 9, wherein the paper base material and the paper base material or the plastic film are adhered to each other by the resin layer. The laminate according to claim 9 or 10, wherein the resin layer is provided at a portion where the paper substrate and the paper substrate or the plastic film are not laminated. A straw using the laminate according to any one of claims 9 to 11. Tableware using the laminate according to any one of claims 9 to 11.