JPH10139032A - Cylindrical paper container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the barrier property and the strength of a paper container to use the paper container as a substitutive container for metal can by a method wherein on the internal side of a paper layer on the surface of which a heat-sealable resin layer is provided, a barrier material comprising an inorganic compound deposited film, and a heat-sealable resin layer are provided to form a laminated material, and the body part of this paper container is formed of the laminated material. SOLUTION: A laminated material which is used for the body part of this paper container has heat-sealable resin layers 1, 9, a paper layer 2, a film 3, an inorganic compound deposited layer 4, a barrier material 7 for which two sheets or more of an inorganic compound deposit film 5 are arranged, and an bonding layer 6. For the barrier material 7, a material for which on aqueous coating layer is formed on the deposited surface of the inorganic compound deposited film 5, may be used, and the water soluable coating layer is formed of a coating layer containing a water soluble high molecule and a metal-alkoxide or its hydrolyzed substance, or a coating agent containing a water soluble high molecule and stannic chloride. Also, for the barrier material 7, it is preferable to arrange the deposited surfaces of the inorganic compound deposited films 5 in a manner to be confronted to each other, and by doing so, a cylindrical paper container which is excellent in barrier property can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylindrical paper container having a paper layer as a main component. More specifically, the present invention relates to a method using a vapor deposited film provided with a vapor deposited layer of an inorganic compound such as silicon oxide or aluminum oxide as a barrier material. The present invention relates to a cylindrical paper container.

[0002]

2. Description of the Related Art A paper container using a paper laminated material mainly composed of a paper layer and provided with a heat-sealable resin layer on an innermost layer and an outermost layer has been used as a container instead of a can or a bottle. In order to enhance the preservability of the contents of these paper containers, a configuration is adopted in which a barrier material is arranged in a laminated configuration. A representative material of the barrier material is an aluminum foil. However, when an aluminum foil is included in the laminated structure, there are problems such as difficulty in sorting after use, and inability to perform incineration as it is. A vapor deposition film provided with a vapor deposition layer of an inorganic compound such as silicon oxide or aluminum oxide has been used as a barrier material instead of the aluminum foil.

[0003] On the other hand, cylindrical metal cans are widely used as easy beverage containers, and these cylindrical metal cans are often used in vending machines. For this purpose, a strong drop strength is required. I have. However, since cylindrical metal cans must be treated as incombustibles after use, they must be treated separately from general waste. As a paper container replacing this cylindrical metal can, a cylindrical paper container has been proposed. However, compared to the cylindrical metal can, the cylindrical paper container was inferior in strength, and thus could not be used directly as a substitute for the cylindrical metal can. In addition to the strength, a certain barrier property is required for preserving the contents, and in this respect, there is a point to be improved.

[0004]

The cylindrical paper container described above is not only inferior in the barrier property but also in the strength of the cylindrical paper can, such as the body being deformed by dropping or the like, as compared with the cylindrical metal can. Because it was inferior, it did not come to practical use. It is an object of the present invention to provide a cylindrical paper container which has improved barrier properties and strength and can be practically used as a container instead of a cylindrical metal can.

[0005]

According to the present invention, there is provided a barrier material comprising, as a base material, a paper layer provided with a heat-sealing resin layer on its surface, and two or more inorganic compound vapor-deposited films disposed inside the base material; A cylindrical paper container using a body formed by molding a laminated material having a heat-sealing resin layer inside the barrier material into a cylindrical shape. A second invention is a cylindrical paper container in which the barrier material is made of a material in which an aqueous coating layer is formed on the evaporation surface of an inorganic compound evaporation film. According to a third or fourth invention, the aqueous coating layer formed on the deposition surface is a coating agent containing a water-soluble polymer and a metal alkoxide or a hydrolyzate thereof, or a coating agent containing a water-soluble polymer and tin chloride. And a cylindrical paper container.

A fifth invention is a cylindrical paper container in which a barrier material using the above-mentioned inorganic compound vapor-deposited film is disposed so that the vapor-deposited surfaces of the inorganic compound vapor-deposited film face each other.

[0007]

The barrier material of the present invention is a vapor-deposited film having an inorganic compound vapor-deposited layer provided on the inside of a substrate, or a coating of a water-soluble polymer and a metal alkoxide or a hydrolyzate thereof on the inorganic compound vapor-deposited layer of the vapor-deposited film. Layer or a coating layer composed of a water-soluble polymer and tin oxide sequentially provided, and a barrier material in which two or more inorganic compound vapor deposited films are arranged. Strength can be improved and barrier properties such as gas barrier can be maintained.

At this time, a cylindrical paper container having more excellent barrier properties can be obtained by arranging the barrier material so that the evaporation surfaces of the inorganic compound evaporation film face each other.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail. FIG. 1 is an explanatory view of a cylindrical paper container of the present invention, FIG. 2 is a cross-sectional view showing one embodiment of a laminated material used for a body of the cylindrical paper container of the present invention, and FIG. 3 is a cylindrical paper container of the present invention. FIG. 10 is a cross-sectional view showing another embodiment of the laminated material used for the body part of FIG.

In FIG. 1, a cylindrical body 10, a circular lid 11 and a bottom 12 above and below the body are arranged.
The folded portion obtained by folding the edges of the lid 11 and the bottom 12 is folded at both ends of the body 10 to overlap each other.
It is a container integrated by heat sealing. Here, the lid 11 is provided with a drinking port 13 at a part, and the drinking port 13 is covered and sealed with a sealing material 14.

In FIG. 2, 1 and 9 are heat-sealing resin layers, 2 is a paper layer, 3 is a film, 4 is an inorganic compound vapor-deposited layer, 5 is a vapor-deposited film, 7 is a barrier material, and 6 is an adhesive layer. It is. Here, the barrier material 7 has two inorganic compound vapor-deposited films 5 arranged thereon.

The film 3 is in the form of a film, and includes polyolefin (polyethylene, polypropylene, etc.), polyester (polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.) and polyamide (nylon-6, nylon-66).
Etc.), polyvinyl chloride, polyimide and the like, or a copolymer of these polymers, etc., can be used as a plastic film usually used as a packaging material. In addition to paper, paper or a laminated material containing paper can be used as the film.

The film 3 includes, for example, an antistatic agent,
Known additives such as an ultraviolet absorber, a plasticizer, a lubricant, and a coloring agent can be added, and are appropriately added as needed.

Further, the surface (deposition surface) of the film 3 may be subjected to a surface modification such as a corona treatment and an anchor coating treatment to improve the adhesion of the deposition layer.

The inorganic compound deposited layer 4 is made of an oxide, nitride, or the like of silicon, aluminum, titanium, zirconium, tin, or the like.
It is composed of a simple substance of fluoride or a composite thereof, and is formed by a vacuum deposition method, a sputtering method, a plasma vapor deposition method (CV).
D method) or the like.

The thickness of the inorganic compound vapor deposited layer 4 is preferably in the range of several tens of degrees to 5000 degrees. However, if it is less than 50 °, there is a problem in the continuity of the thin film, and if it exceeds 3000 °, cracks are liable to occur and the flexibility is lowered.

Further, as a laminated material used for the body of the cylindrical paper container of the present invention, the coating layer 8 is provided on the deposited layer 4 of the deposited film 5 shown in FIG. it can. The coating layer 8 is mainly composed of an aqueous solution containing a water-soluble polymer and at least one of (a) one or more metal alkoxides and hydrolysates thereof, and (b) tin chloride, or a mixed solution of water / alcohol. Consists of a coating agent. A solution in which a water-soluble polymer and tin chloride are dissolved in an aqueous (water or water / alcohol mixture) solvent,
Alternatively, it is formed by coating a solution obtained by mixing a metal alkoxide, which has been subjected to a treatment such as hydrolysis or the like, directly or in advance, on the inorganic compound vapor-deposited layer 4 on the base film 3, and drying by heating.

In the coating agent of the coating layer 8 of the present invention, examples of the water-soluble polymer include polyvinyl alcohol, polyvinylpyrrolidone, starch, methylcellulose, carboxymethylcellulose, and sodium alginate.
In particular, when polyvinyl alcohol (PVA) is used as the coating agent for the gas barrier laminate of the present invention, the gas barrier properties are most excellent. PVA referred to here is generally obtained by saponifying polyvinyl acetate, and has an acetic acid group of several tens%.
It includes, but is not particularly limited to, residual so-called partially saponified PVA to completely saponified PVA in which only a few percent of acetic acid groups remain.

In addition, tin chloride is prepared from stannous chloride (SnC).
l ₂ ), stannic chloride (SnCl ₄ ), or a mixture thereof, and either an anhydride or a hydrate can be used.

The metal alkoxide is a general formula such as tetraethoxysilane [Si (OC ₂ H ₅ ) ₄ ], triisopropoxy aluminum [Al (O-2′-C ₃ H ₇ ) ₃ ], M (OR) _n (M: metal such as Si, Ti, Ai, Zr, R: CH ₃ ,
(An alkyl group such as C ₂ H ₅ ). Among them, tetraethoxysilane and triisopropoxyaluminum are preferable because they are relatively stable in an aqueous solvent after hydrolysis.

Each of the above-mentioned components can be added to the coating agent alone or in combination of several components. Further, as long as the barrier properties of the coating agent are not impaired, an isocyanate compound, a silane coupling agent, a dispersant, or a stabilizer Known additives such as a viscosity modifier and a colorant can be added.

For example, an isocyanate compound added to a coating agent has two or more isocyanate groups (NCO groups) in its molecule, such as tolylene diisocyanate (TDI), triphenylmethane triisocyanate (TTI), There are monomers such as tetramethylxylene diisocyanate (TMXDI), and polymers and derivatives thereof.

As a method for applying the coating agent, conventionally known means such as a dipping method, a roll coating method, a screen printing method, and a spray method, which are usually used, are used. Although the thickness of the film varies depending on the type of the coating agent, the thickness after drying may be in the range of about 0.01 to 100 μm. It is desirable that the thickness be 50 μm.

If a barrier material is provided with two or more inorganic compound vapor deposited films having the above-described structure, and the coating layers 8 of the barrier material 7 are laminated with the surfaces facing each other, the barrier properties are further enhanced. It is preferred.

[0025]

As described above, according to the present invention, the barrier material is formed by depositing an inorganic compound vapor-deposited layer on a film, or a coating layer of a water-soluble polymer and a metal alkoxide or a hydrolyzate thereof on the inorganic compound vapor-deposited layer. The structure using barrier material in which two or more inorganic compound vapor-deposited films are arranged, in which a coating layer composed of a conductive polymer and tin oxide is sequentially provided, improves the rigidity when formed into a cylindrical container and the drop strength. In addition, it is possible to maintain a barrier property such as a gas barrier, and it is possible to use a container having a certain rigidity and a drop strength like a vending machine.

In addition, by forming the barrier material so that the vapor-deposited surfaces of the inorganic compound vapor-deposited films face each other, a cylindrical paper container having more excellent barrier properties can be obtained, and the storage stability of the contents can be improved. Became an excellent container.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a cylindrical paper container of the present invention.

FIG. 2 is a cross-sectional view showing one embodiment of a laminated material used for the body of the cylindrical paper container of FIG.

FIG. 3 is a sectional view showing another embodiment of the laminated material used for the body of the cylindrical paper container of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 9 ... Heat-sealing resin 2 ... Paper layer 3 ... Film 4 ... Evaporation layer 5 ... Evaporation film 6 ... Adhesive layer 7 ... Barrier material 8 ... Coating layer 10 ... Body part 11 ... Lid body 12 ... Bottom body

Claims (5)

[Claims] 1. A barrier material comprising, as a base material, a paper layer provided with a heat-sealing resin layer on the surface thereof, and two or more inorganic compound vapor-deposited films disposed inside the base material, and a heat seal inside the barrier material. A cylindrical paper container using a body formed by molding a laminated material provided with a conductive resin layer into a cylindrical shape. 2. The method according to claim 1, wherein the barrier material is an inorganic compound vapor-deposited film.
The cylindrical paper container according to claim 1, comprising a material having an aqueous coating layer formed on the vapor deposition surface. 3. The cylindrical paper container according to claim 2, wherein the aqueous coating layer comprises a coating layer containing a water-soluble polymer and a metal alkoxide or a hydrolyzate thereof. 4. The cylindrical paper container according to claim 2, wherein the aqueous coating layer comprises a coating agent containing a water-soluble polymer and tin chloride. 5. The cylindrical paper container according to claim 1, wherein the barrier material is disposed so that the vapor-deposited surfaces of the inorganic compound vapor-deposited film face each other.