JP2626781B2 - Packaging material with excellent fragrance retention properties - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a packaging material which is mainly formed into a box-shaped container such as a goebel top-type container, a brick-type container, or a packaging bag.

[Prior Art] Conventional packaging materials used for containers and packaging bags for storing various liquid foods and drinks, tea leaves, spices, etc. are made of a polyolefin-based resin layer on the side to be the inner peripheral layer of the obtained package. It is formed into containers and packaging bags of various shapes by utilizing the thermal bonding performance of the polyolefin-based resin layer.

[Problems to be Solved by the Invention] By the way, a container or a packaging bag obtained by using a packaging material in which the conventional inner peripheral surface layer is composed of a polyolefin-based resin layer is a polyolefin for obtaining the packaging material. The polyolefin-based resin undergoes thermal decomposition to generate volatile components such as aliphatic hydrocarbons when forming the resin-based resin layer or forming a container or a packaging bag using the packaging material.

For this reason, this volatile component migrates into the filling contained in the container or the packaging bag, and has the adverse effect that the filling becomes unpleasant or unpleasant, and is obtained by the packaging material. Since the polyolefin-based resin layer serving as the inner peripheral surface layer of the package easily absorbs or permeates the flavoring component in the filling, the flavor of the filling is easily changed and deteriorated.

In order to eliminate the disadvantages of the conventional packaging materials,
Packaging materials have been proposed in which an inner peripheral layer is formed by a resin layer of an ethylene-vinyl alcohol copolymer instead of a polyolefin resin, but the ethylene-vinyl alcohol copolymer layer is a polyolefin resin. In addition to having a high tensile modulus in comparison with the layer, not only having a disadvantage in impact resistance, but also when molding a molded article having the ethylene-vinyl alcohol-based copolymer layer as a heat sealant layer, a high temperature for the heat sealing temperature is required. Because of the necessity, high-temperature heating at the time of heat sealing causes scorching or peeling due to generation of air bubbles particularly in the paper composite layer portion in the packaging material.

On the other hand, the present invention relates to a method for obtaining a package in which a resin layer serving as an inner peripheral layer of the package has a heat sealant layer in which the fragrance retention performance of various packages obtained using the same is good. Packaging material with good formability that can be easily formed into various kinds of high-quality packages in an orderly condition because the heat-sealing conditions are appropriate and have excellent properties with respect to bending properties I will provide a.

[Means for Solving the Problems] The packaging material of the present invention having the above-mentioned various properties has the following constitution.

That is, the packaging material of the present invention having excellent fragrance retention properties is a first resin layer of an ethylene-vinyl alcohol copolymer and an adhesive polyolefin directly laminated on the first resin layer. A second resin layer made of a base resin, a third resin layer made of a polyolefin resin directly stacked on the second resin layer, and a third resin layer stacked on the third resin layer via an adhesive layer. And a fourth resin layer of a biaxially stretched saturated polyester resin film, wherein the heat sealant layer comprises a first resin layer and a fourth resin layer. Are laminated via an adhesive layer such that the resin layer of the above becomes the outermost layer.

In the packaging material having excellent properties of perfume retention performance of the present invention, the ethylene-vinyl alcohol copolymer forming the first resin layer in the laminated resin layer forming the heat sealant layer has an ethylene content of 40. If less than mol%,
It is not practical because the temperature required for heat sealing becomes high, and when the ethylene content exceeds 60 mol%,
The tendency of the flavoring component to be adsorbed in the filling is increased.

Therefore, the first resin layer in the laminated resin layer constituting the heat sealant layer is preferably formed of an ethylene-vinyl alcohol-based copolymer having an ethylene content of 40 to 60 mol%.

When the thickness of the first resin layer made of an ethylene-vinyl alcohol copolymer is less than 5 μm, the stability of the resin layer is reduced. When the thickness exceeds 40 μm, the impact resistance of the laminated resin layer is reduced. Is further reduced. For this purpose, the first
Is preferably in the range of 5 to 40 μm.

The adhesive polyolefin-based resin layer laminated on the first resin layer is made of, for example, polyethylene, ethylene-α-olefin copolymer, polypropylene, polybutene, polyα-polyolefin such as polyisobutylene, and polybutadiene, polyisoprene. A polydiolefin or a copolymer thereof, and a carbonyl group (—CO—) based on, for example, carboxylic acid, carboxylate, carboxylic anhydride, carboxylic ester, carboxylic amide or imide, aldehyde, ketone, etc. are used alone. Or a cyano group (—C≡N); a hydroxy group; an ether group; an oxirane ring And a copolymer with one or more ethylenically unsaturated monomers.

Specific examples of ethylenically unsaturated monomers include: A. Ethylenically unsaturated carboxylic acids: acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, citraconic acid, 5-norbornene-2,3- B. Ethylene-based unsaturated carboxylic anhydride: Maleic anhydride, citraconic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, tetrahydrophthalic anhydride, etc. C. Ethylene-based unsaturated ester: Ethyl acrylate , Methyl methacrylate, acrylic acid 2
-Ethylhexyl, mono or diethyl maleate, vinyl acetate, vinyl propionate, γ-hydroxy methacrylate, β-hydroxyhydroxy acrylate, glycidyl acrylate, glycidyl methacrylate, β
D. Ethylene unsaturated amide or imide: acrylamide, methacrylamide, maleimide, etc. E. Ethylene unsaturated aldehyde or ketone: macrolein, methacrolein, vinyl methyl ketone,
And vinyl butyl ketone.

It is sufficient that the adhesive polyolefin-based resin layer is formed to a thickness of about 10 μm.

In the packaging material having excellent fragrance retention properties of the present invention, the heat sealant layer laminated on the packaging material substrate is, as described above, a first resin made of an ethylene-vinyl alcohol copolymer. A second resin layer of an adhesive polyolefin resin directly laminated to the first resin layer and the third resin layer of a polyolefin resin directly laminated to the second resin layer And a fourth resin layer of a biaxially stretched saturated polyester resin film laminated to the third resin layer via an adhesive layer.

Since the third resin layer made of a polyolefin resin and the fourth resin layer made of a biaxially stretched saturated polyester resin film are interposed in the laminated resin layer forming the heat sealant layer, this packaging material is used. In the bending step of forming a container or packaging material, cracking of the ethylene-vinyl alcohol-based copolymer resin layer, aluminum foil layer or the like in the packaging material is suppressed.
Thereby, the packaging material of the present invention has excellent properties with respect to bending workability.

The laminated resin layer that forms the heat sealant layer in the packaging material of the present invention includes a first resin layer, a second resin layer, and a third resin layer.
After obtaining a three-layer resin layer by a co-extrusion molding method,
The biaxially stretched saturated polyester resin film is easily bonded to the multilayer resin layer by co-extrusion using an adhesive, for example, an adhesive polyolefin resin, an adhesive saturated polyester resin, an isocyanate adhesive, or the like. can get.

In the packaging material of the present invention, the laminated resin layer is bonded to another packaging material base material using, for example, an adhesive polyolefin resin, an adhesive saturated polyester resin, an isocyanate adhesive, or the like. Easily obtained by:

As the biaxially stretched saturated polyester resin film in the laminated resin layer constituting the heat sealant layer, a polyethylene terephthalate film is most common, and
The polyolefin resin layer forming the resin layer of, for example, polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-α-olefin copolymer (L-LDP
E) and the like.

In the packaging material of the present invention, when the packaging material is used as a packaging material for a flexible packaging container such as a stand pouch, the Al foil is used as a packaging material base material for laminating the laminated resin layer forming the heat sealant layer. Laminated sheets such as biaxially oriented polyester film, biaxially oriented polypropylene film, etc., and when used as packaging materials for containers such as goebel top type paper containers and brick type paper containers, Al foil, paper layer, polyolefin resin layer And the like.

EXAMPLES Hereinafter, a specific configuration of a packaging material having excellent fragrance retention properties of the present invention will be described with reference to production examples.

Example 1 Ethylene-vinyl alcohol copolymer “ethylene content 47 mol%, EVAL G: Kuraray Co., Ltd.] layer (10 μm)
/ Adhesive polyolefin resin [Novatec AP220L: Mitsubishi Kasei Co., Ltd.] layer (10 μm) / Ethylene-α-olefin copolymer resin [Ultzex 2020L: Mitsui Petrochemical Industry Co., Ltd.] layer (40 μm) After forming the co-extruded laminated resin film by the inflation method, a 12 μm-thick biaxially stretched polyethylene terephthalate film [Toray Co., Ltd .: Lumirror] is coated on the ethylene-α-olefin copolymer resin layer surface of the laminated resin film. By bonding with an isocyanate-based adhesive, a laminated resin layer for forming a heat sealant layer was obtained.

On the other hand, a 20 μm-thick low-density polyethylene resin [Mirason 16SP] layer is extruded and coated on the surface of an acid-resistant paper weighing 400 g / m ² , and on the back side, a 15 μm-thick ionomer resin [Mitsui Dupont Chemical Co., Ltd .: Himilan 1652]
A base material for a packaging material was prepared by bonding an Al foil having a thickness of 7 μm using an adhesive layer composed of a layer.

Next, the Al foil surface of the base material for packaging material and the biaxially oriented polyethylene terephthalate film surface of the laminated resin layer described above are bonded and laminated with an isocyanate-based adhesive, and a packaging material [F ] Was obtained.

Comparative Example 1 From the packaging material [F] in Example 1, a comparative packaging consisting of a laminated configuration in which the biaxially stretched polyethylene terephthalate film layer having a thickness of 12 μm in the laminated resin layer forming the heat sealant layer is omitted. Material [G] was prepared.

Comparative Example 2 A low-density polyethylene resin having a thickness of 60 μm [Mirason 16SP] was used in place of the three-layer co-extruded laminated resin film having a thickness of 60 μm in the laminated resin layer forming the heat sealant layer in the packaging material [F] of Example 1. A packaging material [H] for comparison having the same configuration as the packaging material [F] was prepared except for using a layer.

[Experiment 1] Using the packaging materials of Example 1 and Comparative Examples 1 and 2,
A brick-type container with a height of 8.5 cm, a width of 6 cm and a depth of 4 cm is molded by a standard method, and orange juice is 200 m inside.
l was hot-filled.

Each of the brick-type containers was obtained by heat sealing so that the surface of the packaging material substrate in the packaging material became the outer peripheral surface of the container.

After storing 100 of each of the resulting brick-type containers in an atmosphere at 20 ° C. for 7 days, a sensory test of the flavor of the orange juice as the filling and a liquid in the container for checking the suitability of the folding process of the packaging material are performed. Observation of the leak state was performed.

 Table 1 shows the results.

[Operation and Effect of the Invention] The packaging material of the present invention is a first resin layer of an ethylene-vinyl alcohol-based copolymer and a first resin layer of an adhesive polyolefin-based resin directly laminated on the first resin layer. A second resin layer and a third resin layer of a polyolefin resin directly laminated on the second resin layer, and a biaxial laminated resin layer on the third resin layer via an adhesive layer It is provided with a heat sealant layer consisting of a laminated resin layer with a fourth resin layer of a stretched saturated polyester resin film, wherein the laminated resin layer forming the heat sealant layer, with respect to the packaging material base material, The first resin layer is laminated via an adhesive layer so as to be the outermost layer.

The packaging material of the present invention having the above-described configuration is formed into various containers, packaging bags, and the like such that the laminated resin layer forming the heat sealant layer in the packaging material is the inner peripheral surface of the package.

Thus, in the packaging material of the present invention having the above configuration, the ethylene-vinyl alcohol copolymer formed on the side of the packaging material that is in contact with the filling in the laminated resin layer forming the heat sealant layer is used. The first resin layer has an excellent effect on the fragrance retention performance, and the second resin layer of the adhesive polyolefin resin directly laminated on the first resin layer has the first resin layer. It acts to compensate for the low impact resistance points, which are the weak points of the layer.

And, in addition to the first resin layer and the second resin layer, a third resin layer made of a polyolefin resin and a fourth resin layer made of a biaxially stretched saturated polyester resin film are interposed. This prevents cracks generated in the ethylene-vinyl alcohol-based copolymer resin layer, aluminum foil layer, and the like in the packaging material by bending when forming a container or packaging material using the packaging material. The action is performed.

Thus, the packaging material of the present invention has excellent properties with respect to bending workability.

Therefore, according to the packaging material of the present invention, by using the laminated resin layer in the packaging material as a heat sealant layer, the packing material does not have a taste or odor, and has excellent gas barrier properties. Thus, a container, a packaging bag, or the like having no pinholes or the like due to bending can be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location B32B 27/36 B32B 27/36

Claims (1)

(57) [Claims] A first resin layer of an ethylene-vinyl alcohol copolymer, a second resin layer of an adhesive polyolefin resin directly laminated on the first resin layer, and a second resin layer of an adhesive polyolefin resin; A third resin layer of a polyolefin resin directly laminated on the resin layer, and a fourth resin of a biaxially stretched saturated polyester resin film laminated on the third resin layer via an adhesive layer. A heat sealant layer formed of a laminated resin layer composed of a resin layer and a base material for a packaging material is laminated via an adhesive layer such that the first resin layer is the outermost layer. A packaging material that has the characteristic of excellent fragrance retention performance.