JP2002370307A - Laminated packaging material and paper container for liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated packaging material of which the lamination thickness is reduced by reducing the use amount of the adhesive resin between laminated layers while keeping good adhesiveness between the laminated layers, and a paper container for a liquid manufactured from the laminated packaging material. SOLUTION: The laminated packaging material includes a metal vapor deposition film layer, a first resin layer, a coated paper layer and a second resin layer successively from an outer surface side and the appearance thereof from the outer surface side has metal gloss due to the metal vapor deposition film layer. The first resin layer is cured by heating or irradiation with energy beam and the metal surface of the metal vapor deposition film layer and the coated surface of the coated paper layer are bonded.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated packaging material in which the thickness of a laminate is reduced and the amount of an adhesive resin used is reduced, and a liquid paper container made from the material.

[0002]

2. Description of the Related Art Paper containers have been widely used for filling and storing liquids such as beverages and toiletries. The liquid paper container is generally made of a laminated packaging material in which a main paper, a liquid impermeable resin such as polyethylene, polypropylene, or polyvinyl chloride, and other materials are laminated as necessary. For example, a gable-top type container with a gable roof is obtained by cutting a laminated packaging material into a predetermined shape, obtaining blanks joined (sealed) in the vertical direction of the container, sealing the bottom of the blanks in a filling device, and then opening the upper opening. And filled with liquid content and sealed at the top. The laminated packaging material used for the gable-top type container generally has the following laminated structure in order from the side that becomes the outer surface of the packaging. Similarly, the following laminated structure is also described from the side to be the outer surface of the package (hereinafter, referred to as the outer surface side). Printing ink layer / Low density polyethylene / Paper layer / Low density polyethylene

A rectangular brick, polygonal prism, and tetrahedral type container is formed by laminating a laminated packaging material into a tube with a longitudinal vertical line seal, and filling a liquid content from an upper opening of the tube. It is obtained by applying a horizontal line seal in the transverse direction of the tube, forming it into a primary shape, cutting it into individual pieces, folding it, and forming it into a final shape such as a rectangular parallelepiped. The laminated packaging material used for the brick type container generally has the following laminated structure. Low-density polyethylene / printing ink layer / paper layer / low-density polyethylene In general, necessary information such as a product name, a manufacturer, and components, and an image of the contents are printed by the ink of the printing ink layer. .

[0004] The above-mentioned paper containers have been widely used in place of conventional bottles and cans because they are lightweight and inexpensive. And quality changes such as deterioration. In order to solve this, a laminated packaging material including an aluminum foil or an aluminum vapor-deposited film having a barrier property has been used. Further, a laminated packaging material having the following structure has been used in which the appearance of a paper container is distinguished by the metallic luster of an aluminum-deposited film so that the appearance of the paper container is noticeable to consumers. Low-density polyethylene / printing ink layer / aluminized film / low-density polyethylene / paper layer or coated paper layer / low-density or high-density polyethylene / aluminum foil or aluminum-deposited film / low-density polyethylene

[0005]

However, since the above-mentioned laminated packaging materials are generally laminated by the extrusion lamination method, the laminated packaging material is placed between an aluminum vapor-deposited film for metallic luster and a paper layer or a coated paper layer. Was bonded via a molten and extruded thermoplastic bonding resin. For example, by extrusion lamination, low-density polyethylene is melted as an adhesive resin, extruded and sandwiched between an aluminum-deposited film and paper. Suitably, the thickness is about 15 to 25 μm.
If it is less than 0 μm, there is a problem that the adhesiveness is reduced. This requires a certain amount or more of the adhesive resin to be used, which is one of the factors that hinders a reduction in raw material costs.

The present invention has been made in view of the above problems, and a laminated packaging material in which the thickness of a laminate is reduced and the amount of an adhesive resin used is reduced while maintaining good adhesiveness between laminates. It is an object of the present invention to provide a lightweight liquid paper container manufactured from the laminated packaging material.

[0007]

Means for Solving the Problems The present inventors, instead of a thermoplastic resin which is melted and laminated by an extrusion lamination method, is laminated on an adhesive resin layer without using an extrusion lamination method and a thin layer is formed. However, the above problem was solved by using a resin capable of maintaining sufficient adhesiveness. That is, the laminated packaging material of the present invention includes a metal-deposited film layer, a first resin layer, a coated paper layer, and a second resin layer in order from the outer surface side of the package, and the appearance from the outer surface side is based on the metal-deposited film layer. A laminated packaging material having a metallic luster, wherein the first resin layer is cured by heating or irradiation with energy rays, and adheres the metal surface of the metal deposition film layer and the coated surface of the coated paper layer. Make a summary. In particular, the first resin layer has a thickness of 5 μm.
m or less.

[0008] The liquid paper container of the present invention is characterized in that, from the laminated packaging material, the surface on the second resin layer side is a liquid contact surface,
It is characterized by being produced at least by molding, joining, and cutting.

[0009]

Embodiments of the present invention will be described below. The coated paper layer, which is the main layer in the laminated packaging material of the present invention, preferably has an inorganic powder or resin coated on one side of the paper. The coated surface in the case of one side is the side in contact with the first resin layer of the paper in the laminated packaging material, that is, the outer surface side of the packaging. Since the coated surface of the coated paper is excellent in smoothness, a liquid resin (hereinafter, referred to as a first resin composition) to be a first resin layer described later is more thinly and uniformly applied on the coated surface. Can be. Further, inorganic powder, resin, and the like are less likely to adsorb liquid resin than paper and have less adsorption loss, so that a smaller amount of the first resin composition can be thinly and uniformly applied. The thickness of a coating material such as an inorganic powder or a resin coated on paper is preferably 2 to 5 μm for an inorganic powder and 10 to 20 μm for a resin, but can be appropriately changed as necessary.

The paper used for the coated paper layer is usually made from kraft pulp and requires excellent strength and low water absorption. Available paper materials are bleached paper (bleached paper, FBL), unbleached paper (UBL), and bleached and unbleached paper (DUPLE)
X), clay-coated paper, multilayer laminated paper (MB) and the like. Usually, a paper having a thickness of about 200 to 400 gsm is used. The above-mentioned clay-coated paper includes a paper in which clay is coated on one side of the paper by a blade coater in a paper making process and surface smoothness is imparted by a casting method, and has a smooth coated surface. As the inorganic powder used for coating the coated paper layer, an inorganic filler such as calcium carbonate can be used in addition to the above-mentioned clay.
Further, a sizing agent for adhering to the paper is added to the inorganic powder as required.

[0011] The resin used for coating the coated paper layer is preferably polyethylene (hereinafter, referred to as PE), and among PEs, low-density PE (hereinafter, referred to as LDPE) is more preferable in terms of processability. A branched LDPE is preferred from the viewpoint of properties. LDPE coated paper is generally obtained by extruding molten LDPE onto paper with an extruder, sandwiching the both with nip rolls or the like, and cooling.

In the metal-deposited film layer, metal is deposited on one side of the resin film, and the surface in contact with the first resin layer, that is, the inner surface side of the laminated packaging material is the deposited surface. It can be used by appropriately selecting from metal deposition films obtained by a conventionally known method. Examples of the material of the resin film include polyester and polypropylene, and a polyester PET film is particularly preferable. Examples of the metal to be deposited include aluminum and silver, and aluminum is particularly preferable. Due to the metal of the metallized film layer, the appearance from the outer surface of the laminated packaging material of the present invention has a metallic luster.
The deposition thickness is preferably 200 to 400 °.

The first resin composition which is cured by heating or irradiation with energy rays may be blended by appropriately combining conventionally known resin compositions and additives. Examples of the main component of the first resin composition include monomers or oligomers of an energy ray-curable resin that is cured by irradiating an energy ray such as an electron beam, ultraviolet ray, or X-ray, and specifically, an acrylate compound or a methacrylate compound. And unsaturated polyester compounds, etc., and acrylate compounds such as polyester acrylate, epoxy acrylate and urethane acrylate are particularly preferable. Further, as the main agent,
A thermosetting resin that is cured by heating can also be used, and examples thereof include a phenol resin, an epoxy resin, a urea resin, and a melamine resin. The first resin composition is obtained by appropriately combining additives such as a polymerization initiator, a reactive diluent, an antifoaming agent, a light-shielding filler, and the like, with one or two or more of these main ingredients. The first resin composition may have both heat curability and energy ray curability.

In general, an energy-ray-curable resin is a viscous liquid, easy to handle, and can be handled without applying a solvent, so that it does not generate a volatile solvent gas at the time of curing. It is preferably used as a main agent in the first resin composition. The first resin layer is formed by a beam curing method (hereinafter, referred to as E) in which the first resin composition is irradiated with an electron beam.
It is called Method B. ) Is preferred in terms of workability and productivity. In the case of the EB method, the electron beam irradiating apparatus can be used in any system such as an electro curtain system and a scan beam system. The electron beam irradiation dose is 10
It is preferably about 50 kGy, and is selected in consideration of the influence on the adhesive strength, film characteristics, and the like. In addition to the EB method, curing by ultraviolet irradiation is preferable.

A method of laminating a metal-deposited film and a coated paper layer with the first resin composition is described below. Depending on the viscosity of the first resin composition, after uniformly applying the first resin composition on the coated surface of the coated paper with a roll or the like, the metal-deposited film and the coated paper coated, the metal-deposited film The deposition surface is laminated with a nip roll or the like facing the application surface of the first resin composition. Then, when an electron beam, ultraviolet rays, heat rays, etc. are irradiated from the resin film side of the metallized film from the irradiation device, the first resin composition is cured and the vapor-deposited surface of the metal-deposited film adheres to the coated surface of the coated paper layer. Is done. After the irradiation, heating may be performed as needed.

The thickness of the first resin layer is preferably 5 μm or less, and more preferably 3 μm or more from the viewpoint of maintaining the adhesive strength and the workability of coating.

In the present invention, the composition of the resin used for the second resin layer is preferably PE, and is high-density PE, LDPE prepared by a high-pressure method, and resistance to contents when formed into a paper container (water resistance, oil resistance, acid resistance). Linear low-density PE (L)
LDPE), metallocene PE (mLLDPE) and the like. In addition to PE, resins that can be used for the second resin layer include polypropylene, PET, polyamide, ethylene vinyl alcohol copolymer, polyvinylidene chloride, and the like.

The second resin layer may be a single layer or may be composed of a plurality of laminated layers. The plurality of layers of the second resin layer may include two or more layers of resin of the same material. Further, the second resin layer may include one or more layers of aluminum foil and a barrier auxiliary layer described later. Further, in the extrusion lamination method, if a resin having high adhesiveness (hereinafter referred to as an adhesive resin) is laminated via a resin layer extruded by melting, the adhesive strength between the layers is improved. Examples of the adhesive resin include thermoplastic resins such as EAA (ethylene-acrylic acid copolymer) and IO (ionomer). The second resin layer composed of a plurality of layers has, for example, the following laminated structure. Low density polyethylene / low density polyethylene,
Low density polyethylene / Aluminum foil / Low density polyethylene /
Low density polyethylene, polyamide / adhesive resin / low density polyethylene, adhesive resin / PET, adhesive resin / PE
T / adhesive resin / low density polyethylene.

The laminated packaging material of the present invention may be printed on a part of the outer surface side of the metallized film layer with a printing ink in accordance with the design for the appearance. Examples of the type of ink include water-based or oil-based ink for flexographic printing, oil-based ink for gravure printing, curable ink for offset printing, digital printing ink, and UV flexographic ink. As a printing method, for example, flexo, offset, or gravure printing is used. The colors of the inks are generally four colors of cyan, yellow, magenta and black.

In the laminated packaging material, it is preferable to provide another resin layer (hereinafter referred to as an outer surface resin layer) mainly for waterproofing on the outer surface side of the metal-deposited film layer. When the packaging material is used for a brick type container, it is preferably provided on the outer surface side of the ink layer. A single layer is sufficient for the outer surface resin layer, and the preferred composition is the same as the composition of the resin layer.

The laminated packaging material of the present invention includes an adhesive layer (dry laminating agent layer) and an anchor coating agent layer applied for laminating the layers as necessary. The adhesive and the anchor coating agent may be those commonly used for laminated packaging materials. Examples of the adhesive include one- or two-part adhesives such as polyether, vinyl, epoxy, and acrylic. Can be Examples of the anchor coating agent include a polyacrylamine-based anchor coating agent such as a polyurethane-based anchor coating agent. The layered packaging material of the present invention may appropriately contain, as necessary, a layer made of the above-described material or another material in addition to the above-described layer. Further, a quality maintaining agent, an antioxidant, a heat stabilizer, a weather resistance imparting agent, a lubricant and the like can be appropriately added to the laminated packaging material of the present invention as needed.

If the layered packaging material of the present invention contains one or more layers having a barrier property (hereinafter referred to as a barrier auxiliary layer) in addition to the metal-deposited film, the barrier property can be further improved. it can. The barrier auxiliary layer is preferably a layer having at least one of a layer having a light barrier property and a gas barrier property. The light barrier property of the laminated packaging material is such that the whole laminated packaging material has an ultraviolet transmittance of 200 to 4
Preferably less than 20% in the range of 00 nm, 5%
Less than is particularly preferred. The gas barrier properties are, for example, 23
An oxygen permeability of less than 10 cc / m ² 24 hr · atm is preferred under the conditions of ° C. and 85% RH, particularly less than 1 cc / m ² 24 hr · atm.

The barrier auxiliary layer is a thin film layer composed of an organic substance, an inorganic oxide or an inorganic salt; a layer composed of an ethylene vinyl alcohol copolymer, polyamide (nylon), polyvinylidene chloride, polyester, or the like; an inorganic oxide or an inorganic salt Is dispersed in a resin. The barrier auxiliary layer is preferably contained between the coated paper layer and the second resin layer or in a plurality of second resin layers from the viewpoint of maintaining barrier properties and the like.

The thin film layer made of an organic substance, an inorganic oxide or an inorganic salt is prepared by adhering to one or both sides of a resin film. The thin film layer made of an inorganic oxide or an inorganic salt is deposited in a thickness of, for example, about 100 to 5000 ° by a conventionally known means such as vacuum deposition and sputtering. The inorganic oxides or inorganic salts, titanium oxide, silicon oxide (SiO _x), silicates such as magnesium silicate, and alumina. The thin film layer made of an organic material is produced by coating a gas barrier resin such as an acrylate with a thickness of usually 0.3 to 5 μm. In the layer in which the inorganic oxide or the inorganic salt is dispersed in the resin, the same material as the thin film layer can be used for the inorganic oxide or the inorganic salt. The resin to be dispersed is preferably the same resin as the layer made of the ethylene vinyl alcohol copolymer or the like, but may be dispersed in a resin layer of another material. Among the inorganic oxides or inorganic salts, silicon oxide and alumina are particularly excellent in gas barrier properties, and the barrier auxiliary layer is, for example, silicon oxide and alumina deposited and adhered to the polyester film surface, for example, from the viewpoint of improving the barrier properties against humidity. Are preferred.

The method for producing the laminated packaging material and the liquid paper container of the present invention may be a conventionally known production method, and the number of laminating steps and the number of layers laminated at one time are not particularly limited. For example, the following manufacturing method is preferable in terms of workability. First, the metal surface of the metal-deposited film layer and the coated surface of the coated paper layer are overlapped with each other via the viscous liquid first resin composition and pressed with a roller, and then the first resin composition is irradiated with energy rays. Upon curing, an intermediate is obtained that includes a first resin layer bonding the metallized film layer and the coated paper layer. One or more second resin layers in a molten state extruded from an extruder through a die by an extrusion lamination method, and then printed with an ink on the metallized film layer of the intermediate, if necessary, and the intermediate And, if necessary, an aluminum foil and a barrier auxiliary layer, etc., and are laminated by pressing and heating with a roller.

In the step of laminating the intermediate with the second resin layer or the like, the intermediate and a resin film or another film prepared in advance by a stretching method or a non-stretching method are laminated by applying an adhesive. (Lamination) or an extrusion lamination method, which is appropriately selected as needed. For example, in the case of a second resin layer in which an inorganic oxide or the like is deposited on a resin film, dry lamination is preferably used.

As an example of producing the laminated packaging material of the present invention for a gable-top type paper container, first, aluminum is vapor-deposited on one side of a resin film by a vacuum vapor deposition method to obtain a metal-deposited film. Next, between the metal-deposited film and the clay or LDPE-coated paper, a first resin composition mainly composed of an acrylic resin is laminated with a gravure coat, and the first resin composition is cured by EB irradiation so that both are cured. To obtain an intermediate (metallized film layer / first resin layer / clay or LDPE coated paper layer). In addition,
The first resin layer is in contact with the metal surface of the metallized film and the coated surface of the coated paper.

On the other side of the obtained intermediate coated paper, one layer of molten LDPE is extruded and laminated as a second resin layer. After lamination, the appearance design is printed on the resin film surface of the metallized film with printing ink and laminated packaging material for gable-top paper containers: ink layer / metallized film layer / first resin layer / clay or LDPE coated paper layer / An LDPE layer (second resin layer) is obtained. Here, if the coated paper is double-sided coated paper and the coating material on the inner surface is, for example, LDPE, the intermediate and the second resin layer (LDP
The lamination step with E) can be omitted.

Further, as an example of producing a laminated packaging material for a brick type paper container, an external design is printed with a printing ink on the resin film surface of the above-mentioned intermediate metal-deposited film. Next, one layer of the melted LDPE is used as a second resin layer, and one layer of the melted LDPE is used as an outer surface resin layer. (Resin layer) / ink layer / metal deposited film layer / first resin layer / clay or LDPE coated paper layer / LDPE layer (second resin layer).

The liquid paper container of the present invention is subjected to at least each processing of molding, bonding and cutting from the above-mentioned laminated packaging material, so that the surface of the laminated packaging material on the resin layer side is in contact with the liquid surface of the liquid paper container. (A surface in contact with the liquid that is the content). Furthermore, processing such as sterilization, sticking of a straw hole label or a quality indication label, and printing / engraving of the expiration date can be appropriately added. For example, the packaging material for the above-mentioned gable-top type paper container is cut into a predetermined shape to obtain a blank joined (sealed) in the longitudinal direction of the container, and after sealing the bottom of the blank in a filling device, the liquid content is removed from the upper opening. The gable-top type liquid paper container is manufactured by filling and sealing the upper part. Also, the laminated packaging material for brick-type paper containers is formed into a tube by means of a longitudinal vertical line seal, filled with a liquid content from the upper opening of the tube, and subjected to a horizontal line seal in the transverse direction of the tube to form a primary shape. After molding, the individual pieces are cut, folded and formed into a rectangular parallelepiped to obtain a brick type liquid paper container. By appropriately changing the molding, a polygonal prism type or tetrahedral type liquid paper container such as a hexagonal prism or an octagonal prism having a square end face can be obtained by this manufacturing method. Similarly, other types of liquid paper containers can also be arbitrarily manufactured from the laminated packaging material of the present invention by performing various processes.

[0031]

Next, the present invention will be described with reference to examples and comparative examples. (Example 1: Laminated packaging material for gable-top type paper container)
The following materials for laminated packaging materials were prepared. Bleached paper (LDPE (15 gsm) / bleached paper / LDPE) coated on both sides with LDPE (low density polyethylene) as coated paper layer
(30 gsm), total thickness 400 μm, total weight 305 gs
m, hereinafter referred to as LDPE coated paper. ). An electron beam curable acrylic resin (product name: EBTP, Nippon Kasei Co., Ltd.) as the first resin composition Metallized film, thickness 12
μm aluminum evaporated PET film. A printing ink of four colors of cyan, yellow, magenta and black manufactured by Dainippon Ink and Chemicals, Inc.

(Preparation of Intermediate) The first resin composition was uniformly applied by gravure coating at 3 gsm to the 15 g / m ² LDPE surface (outside) of the LDPE-coated paper. The aluminum-evaporated PET film and the applied LDPE-coated paper were laminated with a nip roll sandwiching the evaporation surface toward the applied surface. Next, an electron beam was irradiated from an electron beam irradiation apparatus under a nitrogen atmosphere at an acceleration voltage of 125 kV and an electron dose of 3 M.
Irradiation was performed from the PET side of the aluminum-deposited PET film at rad (30 kGy) to cure the first resin composition to obtain an intermediate. The thickness of the first resin (acrylic resin) layer of the intermediate was 3 μm. (Printing) A four-color ink was printed on the PET film surface of the aluminum vapor-deposited film of the intermediate according to the appearance design to obtain a laminated packaging material (hereinafter referred to as packaging material A). The laminated structure of the packaging material A is as follows. Ink layer / aluminum-deposited PET film layer / acrylic resin layer (3 gsm) / LDPE layer (15 gsm) + bleaching paper layer + LDPE layer (30 gsm)

Example 2 Laminated Packaging Material for Brick Paper Container The following materials for a laminated packaging material were prepared. Clay-coated paper (260 μm thick, weight 21
0 gsm). An electron beam curable acrylic resin common to Example 1. Aluminum evaporated PET film common to Example 1. Four printing inks common to the first embodiment. LDPE without additives as the outer surface resin layer and the second resin layer. Aluminum foil (thickness 6.
5 μm).

(Preparation of Intermediate) The first resin composition was applied to the clay surface of the clay-coated paper by gravure coating.
gsm. The aluminum-evaporated PET film and the applied clay-coated paper were laminated with a nip roll between the evaporated surface and the coated surface. Then
An electron beam was irradiated from a PET side of an aluminum vapor-deposited PET film from an electron beam irradiation apparatus under a nitrogen atmosphere at an acceleration voltage of 125 kV and an electron dose of 3 Mrad (30 kGy) to cure the first resin composition to obtain an intermediate. . The thickness of the first resin (acrylic resin) layer of the intermediate was 3 μm. (Printing) Four colors of ink were printed on the PET film surface of the above-deposited aluminum vapor-deposited film in accordance with the appearance design. (Final lamination) The printed intermediate, the aluminum foil, and the melted and extruded three layers of LDPE are laminated by extrusion lamination to form a laminated packaging material (hereinafter referred to as packaging material B). Obtained. The layer configuration of the packaging material B is as follows. LDPE layer (outer surface resin layer: 15 gsm) / ink layer /
Aluminum deposited PET film layer / acrylic resin layer (3gs
m) / Clay-coated paper layer / LDPE layer (25 gsm) Aluminum foil / LDPE layer (30 gsm)

Comparative Example 1 Laminated Packaging Material for Gable-Top Paper Container The following materials for laminated packaging material were prepared.
A double-sided LDPE coated paper common to Example 1. Aluminum evaporated PET film common to Example 1. LDPE without additives common to Example 2. Four printing inks common to the first embodiment. (Preparation of Intermediate) 15 g / m of the above LDPE coated paper
^{2 The} LDPE surface (outside) and the vapor-deposited surface of the aluminum-deposited PET film were bonded together by extrusion lamination using melt-extruded LDPE, and were laminated by being sandwiched between nip rolls. The intermediate LDPE layer was 15 gsm. (Printing) A four-color ink was printed on the PET film surface of the aluminum vapor-deposited film of the intermediate according to the appearance design to obtain a laminated packaging material (hereinafter referred to as packaging material C). The layer configuration of the packaging material C is as follows. Ink layer / Aluminum-deposited PET film layer / LDPE layer (15 gsm) / LDPE layer (15 gsm) + bleaching paper layer + LDPE layer (30 gsm)

Comparative Example 2 Laminated Packaging Material for Brick Paper Container The following materials for a laminated packaging material were prepared. Clay coated paper common to Example 2. Aluminum evaporated PET film common to Example 1. LDP without additive in common with Example 2
E. Four printing inks common to the first embodiment. Aluminum foil common to Example 2. (Preparation of Intermediate) The clay surface of the clay coated paper described above,
The deposition surface of the aluminum-deposited PET film was adhered to the melt-extruded LDPE by an extrusion lamination method, and laminated by being sandwiched between nip rolls. Intermediate LDPE layer is 15gs
m. (Printing) Four colors of ink were printed on the PET film surface of the above-deposited aluminum vapor-deposited film in accordance with the appearance design. (Final lamination) The printed intermediate, the aluminum foil, and the melted and extruded three layers of LDPE are laminated by extrusion lamination to form a laminated packaging material (hereinafter referred to as packaging material D). Obtained. The layer configuration of the packaging material D is as follows. LDPE layer (15gsm) / ink layer / aluminum-deposited PE
T film layer / LDPE layer (15 gsm) / clay coat paper layer / LDPE layer (25 gsm) aluminum foil / LDPE
Layer (30gsm)

(Evaluation of Adhesion) Five samples each having a width of 25 mm were cut out from the packaging materials A to D obtained in Examples 1 and 2 and Comparative Examples 1 and 2. The adhesiveness between the aluminum-deposited film layer and the coated paper layer of these samples was 50 m
Evaluation was performed using a measuring device (product name: Autograph) manufactured by Shimadzu Corporation by a tensile test at m / min. The average adhesive strength of both packaging materials A and B is 500 g / 25.
mm, but the adhesive strength of both packaging materials C and D was 500 g / 25 mm or less on average.

(Evaluation of Barrier Property) The UV transmittance of the packaging materials A and C was measured and found to be less than 20% in the range of 200 to 400 nm.

[0039]

According to the present invention, a laminated packaging material in which the thickness of the laminate is reduced and the amount of the adhesive resin used is reduced while maintaining good adhesiveness between the laminates, and a lightweight liquid paper container are provided. can get.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) B65D 5/40 B65D 5/40 Z F-term (Reference) 3E060 AA03 AA05 AB04 BA01 BC01 BC04 DA26 DA30 EA03 4F100 AA00C AB01A AB10A AK01B AK01D AK06C AK25B AK41A BA04 BA07 BA10A BA10D CB00 CC00C DE01C DG10C EH46C EH66A EJ53 GB15 GB16 JB14B JN24A

Claims (5)

[Claims] 1. A package includes a metallized film layer, a first resin layer, a coated paper layer, and a second resin layer in order from the outer surface side of the package, and has an appearance from the outer surface side having a metallic luster due to the metallized film layer. A laminated packaging material, wherein the first resin layer is cured by heating or irradiation with energy rays, and the metal surface of the metallized film layer and the coated surface of the coated paper layer are bonded to each other. Packaging material. 2. The laminated packaging material according to claim 1, wherein the thickness of the first resin layer is 5 μm or less. 3. The laminated packaging material according to claim 1, wherein the coated paper layer is formed by coating one side of paper with inorganic powder or low-density polyethylene. 4. The laminated packaging material according to claim 1, wherein the first resin is cured by an electron beam curing method. 5. A liquid paper produced from the laminated packaging material according to claim 1, wherein the surface on the second resin layer side is a liquid contact surface and is formed by at least molding, joining, and cutting. container.