JP2001322624A - Liquid paper container - Google Patents

Abstract

(57) [Summary] [Problem] To have strength and excellent heat resistance, etc.
Excellent barrier properties against oxygen gas, water vapor, etc., for example,
It is an object of the present invention to provide a liquid paper container useful for filling and packaging various liquid drinks such as milk, lactic acid bacteria drinks, liquid soups, fruit juice drinks, barley tea, green tea, oolong tea, alcoholic beverages, and others. SOLUTION: A polyolefin-based resin layer is laminated on one side of a paper base layer, and at least a polyolefin-based resin layer, an adhesive resin layer, and a barrier property are formed on the other side of the paper base layer. A resin layer composed of a resin layer, an adhesive resin layer, and a polyolefin resin layer is directly coextruded and melt-extruded and laminated to form a laminated material. The present invention relates to a liquid paper container characterized by the following.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid paper container, and more particularly, to a liquid paper container having strength and excellent heat resistance.
Furthermore, it has excellent barrier properties against oxygen gas, water vapor and the like, and is filled with various liquid drinks such as milk, lactic acid bacteria drink, liquid soup, fruit juice drink, barley tea, green tea, urong tea, liquor, etc. The present invention relates to a liquid paper container which is useful for:

[0002]

2. Description of the Related Art Conventionally, various types of liquid paper containers have been developed and proposed. However, in general, permeation of oxygen gas, water vapor and the like is prevented in a laminated material constituting the container, and the content is reduced. In order to protect etc., a laminated material is constituted by further interposing a barrier material such as aluminum foil, and then the laminated material is used to make a box to produce liquid paper containers of various forms. ing. Thus, such liquid paper containers are usually single use disposable containers. However, in recent years,
In response to a request for resource reuse, containers that can be collected after use, separated by material, and reused have been demanded. However, in a liquid paper container made of a laminated material using an aluminum foil as described above, it is extremely difficult to separate and collect various materials such as a resin film, a paper base material, an aluminum foil, and others. In fact, the fact is that re-use is virtually impossible.

For this reason, various liquid paper containers having good barrier properties without using a barrier material such as aluminum foil have been developed and proposed. For example, from the outer side to the inner side of the paper container, (1) a paper container formed of a laminated material having a five-layer structure of polyethylene resin layer / paper layer / polyethylene resin layer / biaxially stretched polyamide film layer / polyethylene resin layer (JP-A-63-22624) or (2) polyethylene resin layer / paper layer / polyethylene resin layer / saponified layer of ethylene-vinyl acetate copolymer / A paper container (Japanese Patent Application Laid-Open No. 63-212143) formed of a laminated material having a five-layer structure of a polyethylene resin layer, or, similarly, from the outside to the inside of the paper container,
(3) A paper container formed of a laminated material having a six-layer structure of polyethylene resin layer / paper layer / polyethylene resin layer / saponified layer of ethylene-vinyl acetate copolymer / biaxially stretched polyamide film layer / polyethylene resin layer. (Japanese Unexamined Patent Application Publication No.
No. 160551) have been developed and proposed.

[0004]

However, the paper container as described above is excellent in one aspect, but is not satisfactory in the other aspect. There is a demand for the development of new products and technologies. For example, in the paper container of the above (1), there is a problem that the function is insufficient and the gas barrier property by the biaxially stretched polyamide film layer is insufficient. Further, in the paper container of the above (2), the barrier property of the ethylene-vinyl acetate copolymer due to the saponified layer exhibits a sufficient barrier function in an absolutely dry state, but a significant barrier property in a wet state. However, there is a problem in that the sexual function is lost and the strength as a paper container is lacking. Furthermore, in the paper container of the above (3), since the paper base material layer is provided outside the saponified layer of the ethylene-vinyl acetate copolymer and the biaxially stretched polyamide film layer, an excellent barrier is provided. Although it is possible to have both properties and sufficient strength, since it has both a saponified layer of an ethylene-vinyl acetate copolymer and a biaxially stretched polyamide film layer, on the contrary, the production cost is reduced. There is a problem of remarkable increase, and it is not practical. As described above, the conventional liquid paper container has many advantages, some of which are currently used, but are still not fully satisfactory, and further proposals for new paper containers have been made. It is what is desired. Therefore, the present invention has strength, and is excellent in heat resistance and the like,
Furthermore, it is excellent in barrier properties against oxygen gas, water vapor, etc., and is filled with various liquid drinks such as milk, lactic acid bacteria drink, liquid soup, fruit juice drink, barley tea, green tea, urong tea, liquor, etc. The purpose of the present invention is to provide a useful liquid paper container.

[0005] The applicant has first prepared a base layer of a two-layer laminate in which a polyolefin resin layer is formed on one side of a paper base, and further exposed the paper of the base layer. While melting and extruding low density polyethylene resin on one side
Low density polyethylene (10 μm) / adhesive polyethylene (5 μm) / polyamide (nylon MXD) (10 μm)
m) / adhesive polyethylene (5 μm) / low-density polyethylene (10 μm) to produce a laminated material obtained by laminating a five-layer coextruded laminated film by a polysandramine method.
Furthermore, using the laminated material, a blank plate capable of manufacturing a paper container is manufactured in accordance with a conventional method, and then a liquid paper container is manufactured by using the blank plate. 4-179543). The present inventor has further studied the above-described liquid paper container in various ways, and as a result, laminated a polyolefin-based resin layer on one surface of a paper base material layer,
At least five resin layers of a polyolefin resin layer, an adhesive resin layer, a barrier resin layer, an adhesive resin layer, and a polyolefin resin layer are directly formed on the other surface of the paper base layer. Extrusion and melt extrusion lamination to produce a laminated material, and further using the laminated material, according to a conventional method,
Producing a blank plate capable of producing a liquid paper container, and then
Using this to make a box to make a liquid paper container,
For the liquid paper container proposed above, the manufacturing process can be significantly simplified, and the laminated material can be manufactured very easily and easily without going through complicated work operations and steps, and the cost is significantly reduced. Has reduced strength and strength, and is excellent in heat resistance, and is also excellent in gas barrier properties such as preventing oxygen gas and water vapor from permeating, for example, milk, lactic acid beverage,
Suitable for filling and packaging various liquid drinks such as liquid soup, fruit juice drink, barley tea, green tea, oolong tea, liquor, etc., excellent in storage and storage properties, and environmentally friendly The present invention has been accomplished by finding that a very good packaged product suitable for the present invention can be produced.

That is, according to the present invention, a polyolefin resin layer is laminated on one surface of a paper base layer, and at least a polyolefin resin layer and an adhesive layer are formed on the other surface of the paper base layer. Resin layer, barrier resin layer, adhesive resin layer,
And, a resin material consisting of five layers of a polyolefin-based resin layer is directly co-extruded and melt-extruded to form a laminated material,
Further, the present invention relates to a liquid paper container obtained by using the laminated material and forming the same in a box.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below. First, in the present invention, an example of the liquid paper container according to the present invention will be exemplified and described with reference to the drawings. FIG. 1 is a schematic diagram showing an example of the layer configuration of the laminated material constituting the liquid paper container according to the present invention. FIG. 2 is a schematic plan view showing the configuration of a liquid paper container forming blank plate manufactured using the laminated material shown in FIG. 1, and FIG. 3 is a liquid paper sheet shown in FIG. FIG. 4 is a schematic perspective view showing the configuration of a body for forming a liquid paper container formed using a blank plate for forming a container, and FIG. FIG. 5 is a schematic perspective view showing the configuration of a liquid paper container with a box, and FIG. 5 is a schematic perspective view showing the configuration of a filled and packaged product in which contents are packed using the liquid paper container shown in FIG. .

First, in the present invention, as an example of the laminated material constituting the liquid paper container according to the present invention, the laminated material A constituting the liquid paper container according to the present invention will be exemplified.
As shown in FIG. 1, a polyolefin-based resin layer 2 is laminated on one surface of a paper base material layer 1, and at least a polyolefin-based resin layer is formed on the other surface of the paper base material layer 1. 3. Basically, a resin layer 8 composed of five layers of an adhesive resin layer 4, a barrier resin layer 5, an adhesive resin layer 6, and a polyolefin resin layer 7 is directly co-extruded and melt-extruded and laminated. It has a structure. Although not shown, in the present invention, one side or both sides of the above-mentioned paper base material layer may be subjected to, for example, corona treatment, ozone treatment, plasma treatment, chemical treatment, frame treatment, etc. Surface pretreatment, or a coating treatment with an anchor coating agent or the like, and further a surface pretreatment such as a surface treatment combining the both.

Next, in the present invention, using the laminated material A as described above, as shown in FIG. 9, a blank board B for forming a liquid paper container having a sticking part 10 forming a bottom part, a sticking part 11 forming a top part, and the like is manufactured by punching. Next, in the present invention, as shown in FIG. 3, the liquid paper container forming blank plate B manufactured as described above is used, and the sticking portion 9 constituting the body is attached to the other side end 1.
2 (shown in FIG. 2). Thereafter, the overlapped portion is heat-sealed to form side end seal portions 13 (9, 12) to form the liquid paper container forming body C. To manufacture. Thereafter, in the present invention, as shown in FIG. 4, the liquid paper container forming body part C manufactured above is used, and the sticking part 10 (shown in FIG. 2) constituting the bottom of the lower part is used. The folded portion is heat-sealed according to a conventional method, and the polymerized portion is heat-sealed to form the bottom portion 14 to produce the liquid paper container D according to the present invention. Thus, in the present invention, as shown in FIG. 5, the contents 15 are filled from the opening in the upper part of the liquid paper container D according to the present invention manufactured as described above, and then the opening is hit. The sticking part 11 (shown in FIG. 2) constituting the top part of the upper part is folded in accordance with a conventional method, and then the overlapped part is heat-sealed, for example, from the roof-type seal part. The top part 16 is formed to manufacture a filled and packaged product E using the liquid paper container according to the present invention.

[0010] The examples shown and illustrated above are merely examples, and it goes without saying that the present invention is not limited to these examples. Laminated material in the form, a liquid paper container and the like can be manufactured, for example, instead of the above-mentioned gabelle top type, for example, brick type, flat top type,
Various other types of liquid paper containers and the like can be manufactured. Further, in the above, when manufacturing the laminated material according to the present invention, a liquid paper container and the like, a trunk, a bottom,
Or, when attaching the top part, etc.
Needless to say, a seal system such as a seal or a hot air seal can be adopted. Furthermore, in the above-mentioned pasting, if necessary, in order to protect the end face of the blank plate, for example, a folding hemming method of simply folding, a skive hemming method of cutting the end face and folding, a plastic film on the end face Various end face processing methods, such as a tape bonding method of bonding together, etc., can be adopted. Furthermore, in the present invention, a blanking method for producing a blank for forming a liquid paper container from a laminated material,
A method of manufacturing a liquid paper container forming body from the liquid paper container forming blank plate, and further, a method of manufacturing the liquid paper container forming body by manufacturing a liquid paper container is the same as the conventional method. In addition, it can be carried out according to an ordinary method by a crease applying method, a blanking method, a box making method, or the like.

Next, in the present invention, the materials constituting the laminated material, the liquid paper container and the like according to the present invention as described above, and the manufacturing method thereof will be described. Can be adopted. First, in the present invention, as a paper base layer constituting the liquid paper container according to the present invention, this is a basic material constituting the liquid paper container, and has moldability, bending resistance, rigidity, stiffness, strength, etc. For example, a strongly sized bleached or unbleached paper substrate, or a paper substrate such as pure white roll paper, kraft paper, paperboard, or processed paper, or the like can be used. In the above description, the paper base material constituting the paper base layer has a basis weight of about 80 to 600 g / m ² , preferably a basis weight of about 1 g / m ^2.
It is desirable to use one having a size of about 00 to 450 g / m ² . In the present invention, for example, a desired printing pattern such as a character, a figure, a symbol, a picture, a pattern, and the like may be applied to the paper base material by a normal printing method. is there.

Next, in the present invention, the polyolefin resin layer which is laminated on one surface of the paper base material layer and which is the outermost layer as a liquid paper container may be, for example, a material which is used for producing a liquid paper container. Since it plays a role of bonding with the polyolefin resin layer constituting the innermost layer, it is possible to use a polyolefin resin layer that can be melted and fused to each other by heat. polyethylene,
Medium-density polyethylene, high-density polyethylene, linear (linear) low-density polyethylene, ethylene-α-olefin copolymer copolymerized using metallocene catalyst (single-site catalyst), polypropylene, ethylene-vinyl acetate Copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, methyl Acid-modified polyolefin resin, polyvinyl acetate resin, poly (meth) obtained by modifying pentene polymer, polybutene polymer, polyethylene or polypropylene with an unsaturated carboxylic acid such as acrylic acid, methacrylic acid, fumaric acid, etc. Acrylic resin and other resins can be used Thus, in the present invention, as a method of laminating a polyolefin-based resin layer on one surface of a paper base layer using the above resin, for example, one or more of the above resins may be used. A method of melt-extruding and laminating one side of a paper base layer while extruding it, or using a film or sheet made of the above resin, It can be laminated by a method of dry laminating via an adhesive layer for use. In the above, the thickness of the polyolefin resin layer is, for example, 10 μm to 200 μm.
The m-position is preferably 20 μm to 100 μm
The position is the desired one. In the present invention, a desired printing pattern such as a character, a figure, a symbol, a picture, and a pattern may be applied to the polyolefin-based resin layer by a normal printing method.

Next, in the present invention, at least a polyolefin-based resin layer, an adhesive resin layer, a barrier resin layer, and an adhesive resin layer are directly co-extruded and melt-extruded and laminated on the other surface of the paper base material layer. And a resin layer composed of five layers of a polyolefin-based resin layer. First, at least a polyolefin-based resin layer, an adhesive resin layer, a barrier resin layer, an adhesive resin layer,
As a method of directly co-extruding and melt-extruding a resin layer composed of five polyolefin resin layers, for example, a feed block method or a multi-manifold resin layer is used.
It can be performed by using a multilayer T die casting molding method such as a molding method or other molding methods. Specifically, for example, three types of resins, such as a polyethylene resin, an acid-modified polyolefin resin, an MXD6 nylon resin, or an ethylene-vinyl alcohol copolymer, which will be described later, are used as a molding material. For example, a first polyolefin-based resin layer composed of a polyethylene-based resin / acid-modified on the other surface of the paper base layer by using a multiblock T die-casting method such as a multiblock method or a multi-manifold method. First adhesive resin layer made of polyolefin resin / MX
Three types such as a barrier resin layer composed of D6 nylon resin or ethylene-vinyl alcohol copolymer / a second adhesive resin layer composed of an acid-modified polyolefin resin / a second polyolefin resin layer composed of a polyethylene resin 5
These resin layers are directly co-extruded and melt co-extruded and laminated to form a resin layer of three types and five layers on the other surface of the paper base material layer.

In the present invention, the thickness of each of the resin layers constituting the three types of five resin layers laminated on the other surface of the paper base material layer may be, for example, a first or second polyolefin-based resin layer. As the thickness of the resin layer, about 1 to 200 μm,
Preferably, the thickness is about 5 to 100 μm, and the thickness of the barrier resin layer is about 1 to 100 μm, preferably about 5 to 50 μm. The thickness of the adhesive resin layer is about 1
A thickness of about 100 μm, preferably about 5 to 50 μm is desirable.

In the above, as the first and second polyolefin resin layers made of polyethylene resin or the like, one of the polyolefin resin layers is laminated on the surface of the paper base material layer. It is necessary to have adhesiveness to the substrate layer. Further, since the other polyolefin-based resin layer constitutes the innermost layer of the liquid paper container according to the present invention, it has adhesiveness when producing the liquid paper container, and is directly applied to the contents. Since it is a layer that comes into contact, it is desirable that the layer has fragrance retention and the like in order to protect contents and the like. Further, the first and second polyolefin-based resin layers need to be capable of being co-extruded and have an adhesive property with the first and second adhesive resin layers made of an acid-modified polyolefin-based resin. Things. Thus, in the present invention, the first and second polyolefin-based resin layers as described above include:
Specifically, for example, a mixture of one or more polyolefin-based resins that can be melted by heat and adhere to each other and that are rich in the fragrance retention of the contents and the like can be used.

The above polyolefin resin layer includes:
Specifically, for example, low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear (linear) low-density polyethylene, ethylene-α-olefin polymerized using a metallocene catalyst (single-site catalyst) Copolymer, polypropylene, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-
Methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, methylpentene polymer, polybutene polymer, polyethylene or polypropylene, etc., for acrylic acid, methacrylic acid, fumaric acid, etc. Use of resin such as acid-modified polyolefin resin modified with unsaturated carboxylic acid, ethylene-vinyl alcohol copolymer, polyvinyl acetate resin, poly (meth) acrylic resin, polyvinyl chloride resin, etc. Can be. In the present invention, if the content requires fragrance retention, for example, as an acid component,
A heat-sealable polyester resin such as polyethylene terephthalate-isophthalate copolymer obtained by polycondensing terephthalic acid and isophthalic acid with ethylene glycol, Tosealable ethylene-vinyl alcohol copolymers can be used.

In the present invention, among the above resins, it is particularly preferable to use an ethylene-α-olefin copolymer polymerized using a metallocene catalyst (single-site catalyst). It is. The above resin has the advantage of improving the impact resistance with less propagation of breakage due to having tackiness,
In addition, since the inner layer is in constant contact with the contents, it is also effective for preventing deterioration of environmental stress cracking resistance. Examples of the ethylene-α-olefin copolymer polymerized using the above metallocene catalyst include, for example, a catalyst obtained by combining a metallocene complex and alumoxane such as a catalyst obtained by combining zirconocene dichloride and methylalumoxane, that is, a metallocene-based catalyst. An ethylene-α-olefin copolymer obtained by polymerization using a catalyst can be used. The metallocene catalyst has a non-uniform active site and is called a multi-site catalyst, whereas the existing catalyst is called a single-site catalyst because the active site is uniform. Specifically, the product name "Kernel" manufactured by Mitsubishi Chemical Corporation, the product name "Evolu" manufactured by Mitsui Petrochemical Industry Co., Ltd., the product name "EXACT" manufactured by EXXON CHEMICAL, USA (EXACT) ", a product name" AFFINITY ", a product name" ENGE- "manufactured by DOW CHEMICAL, USA
An ethylene-α-olefin copolymer polymerized using a metallocene catalyst such as “ENGAGE” can be used. In the present invention, when an ethylene-α-olefin copolymer polymerized using the above-mentioned metallocene catalyst is used, low-temperature heat-sealing properties are possible when a liquid paper container is manufactured. It has advantages.

In the above, the barrier resin layer made of MXD6 nylon resin or ethylene-vinyl alcohol copolymer has a property of preventing permeation of oxygen gas, water vapor and the like, and is co-extrusion molded. And a resin having an adhesive property with the first and second adhesive resin layers can be used. Specifically, for example, an MXD6 nylon resin, an ethylene-vinyl alcohol resin,
Resins such as copolymers, polyvinyl alcohol resins, polyacrylonitrile resins, and others can be used. Thus, in the present invention, among the above resins, it is preferable to use an MXD6 nylon-based resin which has a barrier property against oxygen gas or water vapor and is excellent in co-extrusion moldability. . As the above MXD6 nylon resin, more specifically,
For example, meta-xylene diamine, aromatic diamine such as para-xylene diamine, and adipic acid, suberic acid, sebacic acid, cyclohexanedicarboxylic acid, terephthalic acid,
A crystalline aromatic polyamide-based resin obtained by a polycondensation reaction with a dicarboxylic acid such as isophthalic acid or a derivative thereof can be used. Specifically, for example, nylon MXD6 (trade name, manufactured by Mitsubishi Gas Chemical Co., Ltd.) can be used.

In the present invention, in order to improve the extrusion suitability or the adhesion to the paper substrate,
As the barrier resin layer, for example, one or two or more aliphatic polyamide resins are added to the above-described crystalline aromatic polyamide resin, and the barrier resin layer is formed from both of them. Can be configured. Examples of the aliphatic polyamide resin include hexamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4- or 2,4,4-trimethylhexamethylenediamine, 1,3- Or 1,4-
Aliphatic and alicyclic diamines such as bis (aminomethyl) cyclohexane and bis (p-aminocyclohexylmethane) and dicarboxylic acids such as adipic acid, suberic acid, sebacic acid, cyclohexanedicarboxylic acid, terephthalic acid, and isophthalic acid Aliphatic polyamide obtained by a polycondensation reaction with an acid or a derivative thereof, ε-aminocaproic acid,
A polyamide resin obtained by condensation of 1-aminoundecanoic acid or the like, a polyamide resin obtained from a lactam compound such as ε-caprolactam, ω-laurolactam, or a mixture thereof can be used. Specifically, for example, nylon 6, nylon 66, nylon 9, nylon 11, nylon 12, nylon 6/66,
An aliphatic polyamide resin such as nylon 66/610 can be used. As the compounding ratio of the crystalline aromatic polyamide-based resin and the aliphatic polyamide-based resin,
It can be used by mixing at a mixing ratio of about 0 to 40% by weight of the aliphatic polyamide-based resin with respect to 60 to 100% by weight of the crystalline aromatic polyamide-based resin.

Further, in the above, the first and second adhesive resin layers made of an acid-modified polyolefin resin or the like are used for bonding the above-mentioned polyolefin resin layer and the barrier resin layer. It is necessary that both of them have adhesive properties and that they can be co-extruded. Thus, in the present invention, as the first and second adhesive resin layers as described above, specifically, for example, a polyolefin-based resin that can be melted by heat and fused together as described above. Or a mixture of one or more of the above. Specifically, as described above, for example, polymerization was performed using a low-density polyethylene, a medium-density polyethylene, a high-density polyethylene, a linear (linear) low-density polyethylene, and a metallocene-based catalyst (single-site catalyst). Ethylene-α-olefin copolymer, polypropylene, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-
Methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, methyl pentene polymer, polybutene polymer, polyethylene or polypropylene, etc. are converted into acrylic acid, methacrylic acid, fumaric acid, maleic acid, Acid-modified polyolefin resin modified with unsaturated carboxylic acid such as maleic anhydride and others,
Resins such as ethylene-vinyl alcohol copolymer, polyvinyl acetate resin, poly (meth) acrylic resin, polyvinyl chloride resin and others can be used. Thus, in the present invention, among the above-mentioned resins, in particular, polyethylene, polypropylene or the like having strong adhesiveness and co-extrusion properties is used for acrylic acid, methacrylic acid, fumaric acid, It is preferable to use an acid-modified polyolefin resin modified with an unsaturated carboxylic acid such as maleic acid, maleic anhydride, or the like.

In the present invention, since the packaging container is usually subjected to severe physical and chemical conditions, strict packaging suitability is required for the packaging material constituting the packaging container. And various conditions such as deformation prevention strength, drop impact strength, pinhole resistance, heat resistance, sealability, quality maintenance, workability, hygiene, etc. are required. Any material that satisfies the above conditions can be selected and used.Specifically, for example, low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene, Ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid or methacrylic acid copolymer, Chillpentene polymer, polybutene resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinylidene chloride resin, vinyl chloride-vinylidene chloride copolymer, poly (meth) acrylic resin, polyacrylonitrile resin, Polystyrene-based resin, acrylonitrile-styrene copolymer (AS-based resin), acrylonitrile-butadiene-styrene copolymer (ABS-based resin), polyester-based resin, polyamide-based resin, polycarbonate-based resin, polyvinyl alcohol Resin, saponified ethylene-vinyl acetate copolymer, fluororesin,
Known resins such as diene resins, polyacetal resins, polyurethane resins, nitrocellulose, and others can be arbitrarily selected and used in combination.

In the present invention, when the above materials are used, for example, pigments, antioxidants, slip agents, antistatic agents, inorganic fillers, ultraviolet absorbers, etc. And the like can be optionally used.

In the present invention, as the anchor coating agent used in the above-mentioned surface pretreatment, for example, isocyanate type (urethane type), polyethyleneimine type, polybutadiene type, organic titanium type, etc. Anchor anchor
Ting agents and the like can be used.

In the present invention, the liquid paper container according to the present invention produced as described above is suitable for filling and packaging of various articles, for example, liquids such as milk, dairy products, juices, seasonings, etc. It can be used for filling and packaging of foods, chemicals such as adhesives and pressure-sensitive adhesives, miscellaneous goods such as pharmaceuticals, cosmetics, detergents, and others.

[0025]

EXAMPLES The present invention will be described more specifically with reference to examples. Example 1 A paper having a basis weight of 340 g / m ² was used as a support, and a low-density polyethylene resin [density: 0.923
g / cc, melt index (MI) = 3.7, melting point = 111 ° C.] and extruded to form a low-density polyethylene resin layer having a thickness of 20 μm. Next, the other surface of the paper was subjected to a corona treatment, and then a nylon MXD6 resin [trade name, manufactured by Mitsubishi Gas Chemical Company, density, 1.22 g / cc, melt index ( MI) = 7, melting point = 243 ° C.] and a maleic anhydride-modified adhesive polyolefin resin [density: 0.91 g
/ Cc, melt index (MI) = 9.5] and low density polyethylene resin [density, 0.923 g / cc, melt index (MI) = 3.7, melting point = 111 ° C.]
These three types of resins are used, and they are melt co-extruded and laminated while directly co-extruding them using a feed block type multilayer T-die co-extrusion machine, according to the present invention having the following layer constitution. A laminated material was manufactured. Low-density polyethylene resin layer having a thickness of 20 μm / paper having a basis weight of 340 g / m ² / low-density polyethylene resin layer having a thickness of 20 μm / maleic anhydride-modified adhesive polyolefin resin layer having a thickness of 5 μm / nylon having a thickness of 10 μm MXD6 resin layer / maleic anhydride-modified adhesive polyolefin resin layer having a thickness of 5 μm / thickness 2
0 μm low-density polyethylene resin layer

Example 2 A paper having a basis weight of 340 g / m ² was used as a support, and a low-density polyethylene resin [density: 0.923 g /
cc, melt index (MI) = 3.7, melting point = 1
11 ° C.] to form a low-density polyethylene resin layer having a thickness of 20 μm. Next, the other side of the paper was subjected to corona treatment, and then the ethylene-vinyl alcohol copolymer [ethylene content: 32 mol%, density = 1.19, melt index, MI = 1.3], a maleic anhydride-modified adhesive polyolefin resin [density, 0.91 g / cc, melt index (MI) = 9.5], and a low-density polyethylene resin [density, 0.923 g / cc, Melt index (MI) = 3.7, melting point = 111 ° C.], and using a feed block type multilayer T-die co-extruder to directly extrude them, By extrusion lamination, a laminated material according to the present invention having the following layer constitution was produced. Low-density polyethylene resin layer having a thickness of 20 μm / paper having a basis weight of 340 g / m ² / low-density polyethylene resin layer having a thickness of 20 μm / maleic anhydride-modified adhesive polyolefin resin layer having a thickness of 5 μm / ethylene having a thickness of 10 μm -Vinyl alcohol copolymer resin layer / maleic anhydride modified adhesive polyolefin resin layer having a thickness of 5 μm / low density polyethylene resin layer having a thickness of 20 μm

Example 3 A paper having a basis weight of 340 g / m ² was used as a support, and low-density polyethylene resin [density: 0.923
g / cc, melt index (MI) = 3.7, melting point = 111 ° C.] and extruded to form a low-density polyethylene resin layer having a thickness of 20 μm. Next, the other surface of the paper was subjected to a corona treatment, and then a nylon MXD6 resin [trade name, manufactured by Mitsubishi Gas Chemical Company, density, 1.22 g / cc, melt index ( MI) = 7, melting point = 243 ° C.] A nylon resin mixture consisting of 85 parts by weight and 15 parts by weight of 6 nylon resin, and a maleic anhydride-modified adhesive polyolefin resin [density, 0.91 g / cc, melt index (M
I) = 9.5] and a low-density polyethylene resin [density,
0.923 g / cc, melt index (MI) =
3.7, melting point = 111 ° C.]
These were melt co-extruded and laminated while directly co-extruding them using a feed block type multilayer T-die co-extruder to produce a laminated material according to the present invention having the following layer constitution. Low-density polyethylene resin layer having a thickness of 20 μm / paper having a basis weight of 340 g / m ² / low-density polyethylene resin layer having a thickness of 20 μm / maleic anhydride-modified adhesive polyolefin resin layer having a thickness of 5 μm / nylon having a thickness of 10 μm MXD
Mixed resin layer of 6 resin and 6 nylon resin / maleic anhydride-modified adhesive polyolefin resin layer of 5 μm thickness / low density polyethylene resin layer of 20 μm thickness

Comparative Example 1 In Example 1, the polyamide resin (6 nylon resin) was used as the barrier layer instead of the nylon MXD6 resin, and the other conditions were the same as in Example 1 above. A laminated material having the following layer configuration was manufactured. Thickness 2
0 μm low-density polyethylene resin layer / 340 g of basis weight /
m ² of paper / thickness 20μm low density polyethylene resin layer /
5 μm thick maleic anhydride-modified adhesive polyolefin resin layer / 10 μm thick 6 nylon resin layer / 5 μm thickness
m maleic anhydride modified adhesive polyolefin resin layer / 20 μm thick low density polyethylene resin layer

EXPERIMENTAL EXAMPLE Using the laminated materials manufactured in Examples 1, 2, 3 and Comparative Example 1, a blank plate was punched by a predetermined method, and furthermore, a blanking process was performed by a predetermined box making process. , Bottomed container, 7
A gable-top type liquid paper container having a size of 0 mm × 70 mm and a height of 180 mm was manufactured. Next, using the above-mentioned liquid paper container, liquid foods such as milk and orange juice were filled and packaged by a predetermined filling and packaging machine to produce a filled and packaged product. Next, the oxygen permeability and container strength of the liquid paper container manufactured above were measured under the following measurement conditions. The above oxygen permeability is measured by an oxygen permeability meter [Oxtran, manufactured by Modern Control Co., Ltd.]
And the relative humidity was 90% RH. In addition, the strength of the container, the bottomed container from a height of 90cm, with the lower surface down, once free fall,
The state of liquid leakage was visually observed and measured. The results are shown in Table 1 below.

[0030]

As is evident from the results shown in Table 1 above, those according to Examples 1, 2, and 3 show good oxygen permeability and the container strength can withstand practical use. In the case of Comparative Example 1, the container strength was sufficient, but the oxygen permeability was extremely poor.

[0032]

As is apparent from the above description, the present invention has a structure in which a polyolefin-based resin layer is laminated on one surface of a paper base material layer, and the other surface of the paper base material layer is formed on the other surface. A laminated material is manufactured by directly co-extruding a resin layer composed of at least five layers of a polyolefin-based resin layer, an adhesive resin layer, a barrier resin layer, an adhesive resin layer, and a polyolefin-based resin layer and melt-extruding the resin layer. Further, using the laminated material, according to a conventional method, manufacture a blank plate capable of manufacturing a liquid paper container, and then manufacture a liquid paper container using this to manufacture a liquid paper container. With respect to the liquid paper container proposed by the present applicant, the manufacturing process can be simplified, the laminated material can be manufactured very easily and easily without going through complicated work operations, and the cost can be reduced. Has strength, excellent heat resistance, and Oxygen gas, excellent gas barrier properties to prevent the permeation of water vapor, etc., for example, milk, lactic acid bacteria drink, liquid soup, fruit juice drink, barley tea, green tea, oolong tea, liquor, various liquid drinks such as other It has filling and packaging suitability for filling and packing, and has excellent storage and storage properties, and
An extremely good package product suitable for environmental protection can be manufactured.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a layer configuration of a laminated material constituting a liquid paper container according to the present invention.

FIG. 2 is a schematic plan view showing a configuration of a liquid paper container forming blank plate manufactured using the laminated material shown in FIG.

FIG. 3 is a schematic perspective view showing a configuration of a body portion for forming a liquid paper container manufactured using the blank plate for forming a liquid paper container shown in FIG. 2;

FIG. 4 is a schematic perspective view showing a configuration of a liquid paper container manufactured using the liquid paper container forming body shown in FIG. 3;

FIG. 5 is a schematic perspective view showing a configuration of a filled package product in which contents are filled and packaged using the liquid paper container shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Paper base material layer 2 Polyolefin resin layer 3 Polyolefin resin layer 4 Thermal adhesive resin layer 5 Barrier resin layer 6 Thermal adhesive resin layer 7 Polyolefin resin layer 8 Five-layer resin layer 9 Adhering part 10 Adhesion Attachment part 11 Attachment part 12 Side end part 13 Side end seal part 14 Bottom part 15 Contents 16 Top part consisting of roof type seal part A Laminated material B Blank plate for forming liquid paper container C For forming liquid paper container Body D Liquid paper container E Filled packaging product l Folded crease

 ──────────────────────────────────────────────────の Continuing on the front page F term (reference) 3E060 AA05 AB04 BA03 BC04 CF02 DA11 DA20 DA30 EA03 EA13 4F100 AK03 AK03B AK03C AK03D AK06 AK21C AK64C AK69C AL07 AT00A BA04 BA07 BA10B CB03 DA01 JDG51JE12

Claims (3)

[Claims] 1. A polyolefin resin layer is laminated on one surface of a paper base layer, and at least a polyolefin resin layer, an adhesive resin layer, and a barrier are formed on the other surface of the paper base layer. A resin layer composed of a functional resin layer, an adhesive resin layer, and a polyolefin resin layer is directly coextruded and melt-extruded to form a laminated material. Further, the laminated material is used. A liquid paper container characterized by forming a box. 2. The paper base material layer according to claim 1, wherein the paper base layer has been subjected to a corona treatment or a framing treatment and / or a surface treatment with an anchor coating agent beforehand. The liquid paper container described in the above. 3. The method according to claim 1, wherein the barrier resin layer comprises an MXD6 nylon resin layer, an ethylene-vinyl alcohol copolymer resin layer, or a polyvinyl alcohol resin layer. Liquid paper container to be described.