JPH01240463A - Easily openable vessel and lid therefor - Google Patents

Abstract

PURPOSE:To obtain an easily openable vessel and a lid, by giving an easibly separable adhesive force on unsealing to one of respective inter-layers among an opening periphery of the vessel and a sealing layer, mutual sealing layers and a sealing layer and a lid member and by giving a difficultly separable adhesive force to the rest and by providing a ring-shape non-adhesive part with the size more than a specified dimensions from the inner end at one of the rest inner layer. CONSTITUTION:A vessel flange 1, a lid member 2 and sealing layers 3, 4 are sealed by bonding after contents are filled in the vessel. One of adhesive forces among an inter-layer adhesive force between the periphery 1 of the vessel opening and the sealing layer 4, that between sealing layers 3, 4 and that between the sealing layer 3 and the lid member 5 is designed in an easily separable degree on unsealing. And the rest inter-layers are designed in difficultly separable degrees than the above. Further, a ring type non-adhesive part 6 with the width (t) more than 0.5mm from the inner end is provided in one of the rest inner layers. When an internal pressure acts on the lid member, a stress is centralized at the outer end of the non-adhesive part and separation from separable inter layers becomes difficult inside the vessel and it can be sealed better and easily unsealed because of peeling off from the separable inter layer when a tongue 5 is raised.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an easy-to-open container with excellent sealing and opening properties for storing and packaging foods, medicines, cosmetics, etc., and a lid used therefor. .

[Prior Art] Packaging containers with high sealability and easy opening are desired in many fields such as food packaging (retort food), pharmaceuticals, and agricultural chemicals. Instead of peeling off the lid material from the heat-sealed part as in the past, we have strengthened the heat seal and improved its tightness, and it is now easier to peel it off between the layers of the multilayer container body, which has appropriate interlayer adhesive strength. An easy-to-open multi-layer container was proposed (Japanese Patent Laid-Open No. 1983-1978)
(Japanese Patent Application Laid-Open No. 63-25037), processing such as weakening lines and cuts is required to cut the peeling layer when peeling the layers of a multilayer container, and performance may vary depending on the position of the seal when sealing. There were also problems in that it could not be applied to any container such as a single-layer container or a blow-molded container.

[Problem to be solved by the invention]

The present invention provides an easy-to-open container that has pressure-resistant sealing properties, good unsealability, simple structure, and a wide range of applications that can be applied to various types of containers other than thermoformed containers, and a lid used therefor. The purpose is to provide.

[Means to solve the problem]

The invention according to claim 1 is a packaging container formed by adhering a container opening periphery, a lid material, and a bonding layer consisting of at least two layers, the interlayer adhesive strength between the container opening periphery and the bonding layer formed by these. , one of the interlayer adhesion between the bonding layers and the interlayer adhesion between the bonding layer and the lid material is set to a size that makes it easy to peel off when the lid material is opened, and the remaining interlayer adhesive strength is set to a level that makes it difficult to peel off. The present invention provides an easy-to-open packaging container, which is characterized in that it has an adhesive strength of a certain magnitude and that an annular non-adhesive part of 0.5 ma or more from the inner edge is provided between one of the remaining layers. Yes, the invention according to claim 2 relates to a lid used for the easy-to-open container according to claim 1, and is a lid formed by adhering a lid material and a bonding layer consisting of at least two layers. One of the interlayer adhesive force between the bonding layers formed and the adhesive force between the bonding layer and the lid material is such that it is easy to peel off when the lid material is opened, and the other is an adhesive force that is difficult to peel off. In addition, an easy-to-open lid characterized in that an annular non-adhesive part of 0.5 ata or more from the inner edge is provided between the layers having high adhesive strength, and the bonding layer can be fixed to the periphery of the opening of the container. It provides:

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a front view showing an embodiment of the easy-to-open container of the present invention, with a portion thereof being shown in cross-section.

Figures 2(a), 2(b), and 2(C) are partial sectional views showing the state of adhesion between the lid and container flange in Figure 1;
Figure (a) shows the lid sealed, Figure 20)) shows the sealed container under internal pressure, and Figure 2 (C) shows the container being opened. There is.

In FIG. 2(a), 1 is a container opening peripheral portion (flange), 2 is a lid material, 3.4 is a bonding layer between the container flange and the lid material, and 5 is a grip portion. The container flange, lid material, and bonding layer are adhered and sealed after filling the container with the contents.

In the case shown in Fig. 2(a), N3 and layer 4 are releasably bonded, layers 2 and 3 are strongly bonded from the inside with a width L left, and flange l and layer 4 are bonded tightly. is strongly adhered over almost the entire surface, but as long as the interlayer adhesion between the three layers has such a relationship, any layer may be releasably adhered. The same applies to layers that are strongly bonded and layers that have non-bonded parts.

The material of the container body used in the present invention is not particularly limited, and may include polyolefin resins such as polyethylene and polypropylene, polystyrene resins, polyamide resins, polyester resins, polycarbonate resins,
Ethylene-vinyl alcohol copolymer, polyvinylidene chloride resin, polyacrylonitrile, or a mixture thereof, or a resin containing 5 to 70% by weight of a thermoplastic elastomer, various additives, or inorganic filler.
There are metals, paper, etc.

For the container body of the present invention, a multilayer material having two or more layers of other materials may be used for the purpose of improving gas barrier properties and reducing deformation when used as a container. Examples of layers made of other materials include resin layers such as ethylene-vinyl alcohol copolymer, polyvinylidene chloride, nylon, and polyethylene terephthalate; aluminum vapor-deposited layers; and materials with excellent gas barrier properties such as aluminum foil, aluminum, iron, and copper. There are many things that can be mentioned. The layer made of these other materials may be one layer, a multilayer body consisting of two or more layers, or a resin layer containing 10 to 80% by weight of an inorganic filler. Furthermore, it may be a composite material with metal, paper, etc.

The container body of the resin layer can be formed by molding a plastic sheet, coextrusion multilayer sheet, or laminate sheet obtained using the above-mentioned resin by vacuum forming, pressure forming, press molding, injection molding, injection blow molding, etc. It can be obtained by molding by blow molding or the like. Furthermore, it can also be obtained by thermoforming a multilayer film on the inside of a container such as paper.

As the lamination process, methods such as extrusion lamination, hot melt lamination, dry lamination, and wet lamination can be used.

Moreover, a composite container of paper, metal, or these and resin can be obtained by forming a container body by press molding, adhesion, seaming, etc.

The lid material used in the present invention is a plastic monomer such as polypropylene, polyolefin resin containing 20 to 80% by weight of an inorganic filler, polycarbonate resin, polyester resin, ethylene-vinyl alcohol copolymer, polyvinylidene chloride resin, polyamide resin, etc. layer film,
Or a multilayer film of these plastics, paper, aluminum foil, aluminum, iron, copper, or a composite material thereof.

In the present invention, the opening periphery of the container as described above and the lid material are bonded together through a bonding layer having approximately the same shape as the opening periphery, which consists of two layers, and the contents are sealed. The adhesive force between the three layers formed by the material of each layer, that is, the interlayer adhesive force between the container opening periphery and the bonding layer, the interlayer adhesive force between the bonding layers, and the interlayer adhesive force between the bonding layer and the lid material,
By appropriately selecting the formation method, the adhesive strength of one of these layers is set to a level that makes it easy to peel off when the lid material is opened, and the adhesive strength of the remaining layers is set to a level that makes it difficult to peel off. do. Furthermore, between one of these layers, 0 from the inner edge
．． An annular non-bonded part 6 having a width of 5M or more, preferably 0.5 to 10 IIn, more preferably 0.5 to 5 IIn.
will be established. By providing a non-adhesive part, when internal pressure is applied to the lid material, stress is concentrated at point A at the outer edge of the non-adhesive part, as shown in Figure 2(b), and peeling from the separable layer is prevented. This prevents this from happening from the inside and improves the sealing performance of the container. When opening packaging containers, please refer to Section 2 (C).
As shown in the figure, by lifting the grip portion 5, the peelable layers are separated and the package can be opened easily.

In the bonding layer of the present invention, it is also possible to further provide another layer in the bonding layer consisting of two layers.

Next, as shown in Figures 2 (a) to (C), when the adhesive force between the two layers of the bonding layer is set to a level that allows easy peeling, the material of the bonding layer is There are those that utilize interlayer peeling, those that utilize adhesive peeling, and those that utilize adhesive peeling that has an appropriate adhesive strength.

An example of the former is a bonding layer in which one layer is a high-density polyethylene resin layer, the other layer is a resin mixture layer of polypropylene resin and polyethylene resin, and these are coextruded to form a bonding layer. It will be done.

In addition to ethylene homopolymer, the high-density polyethylene resin used in the high-density polyethylene resin layer includes propylene, α-1, butene-1, pentene-1,3-methylbutene-1,4-methylpentene-1, etc. Examples include copolymers with olefins. In this copolymer, the proportion of copolymerizable monomers is preferably 10 mol% or less.

This high-density polyethylene resin has a density of 0.940 to O
', 975 g/cJ, and may be a mixture of different densities and molecular weight distributions.

In addition to highly crystalline propylene homopolymer, the polypropylene resin used in the resin mixture layer includes ethylene, butene-11pentene-1,3-methylbutene-1
, 4-methylpentene-1, and mixtures thereof.

Random copolymers include mixtures with homopropylene obtained by multistage polymerization. In the copolymer,
It is preferable that the proportion of the copolymerized monomer is 10 mol% or less. Further, these polypropylene resins preferably have a melt index in the range of 0.1 to 20. Further, as the polyethylene resin used for the resin mixture layer, any of low density (high pressure low density polyethylene, linear low density polyethylene, etc.), medium density and high density polyethylene can be used, and In addition to ethylene homopolymer, propylene, butene-1,
Copolymers with α-olefins such as pentene-1,3-methylbutene-1,4-methylpentene-1 or vinyl acetate, or mixtures thereof can also be used. In the copolymer, the proportion of copolymerizable monomers is preferably 10 mol% or less. In addition, these polyethylene resins have a melt index of 0.02.
~50 and the density is 0.900 to 0.97
A range of 5 g/crA is preferred.

The ratio of the polypropylene resin to the polyethylene resin is preferably 50:50 to 97: by weight.
3, more preferably in the range of 60:40 to 95:5.

Furthermore, a third resin component can be added to this resin mixture, if desired, in order to improve its compatibility. Such third resin components include, for example, modified polyolefins modified with unsaturated carboxylic acids or derivatives thereof, ethylene-hinyl acetate copolymers, ethylene-acrylate copolymers, ethylene-propylene rubber,
Ethylene-propylene-diene rubber, polybutene, polyisobutylene, polybutadiene rubber, polyisoprene rubber, acidic poly-4-methylpentene-1
, styrene-butadiene rubber, acrylonitrile-butadiene rubber, and ionically crosslinked olefin copolymers (ionomers), each of which may be used alone or in combination of two or more. These third components are preferably used in an amount of 30 parts by weight or less per 100 parts by weight of the polypropylene resin.

Examples of the latter include polyethylene such as low-density polyethylene or high-density polyethylene; polypropylene; ethylene-α-olefin copolymer with a density of 0.86 to 0.96; ethylene-vinyl acetate copolymer. metal salts such as zinc, sodium, and calcium salts of ethylene-ethyl acrylate copolymer, ethylene-ethyl acrylate copolymer, ethylene-maleic anhydride copolymer, and ethylene-acrylic acid copolymer ) and other ethylene-unsaturated carboxylic acid copolymers; the resin layer is easily heat-sealable to the container opening periphery and lid material, and the other side layer is natural rubber, styrene-butadiene rubber, neoprene rubber, etc. Butyl rubber, polyisobutylene, polyacrylic ester, polyvinyl acetate,
Resins such as polyvinyl ether, coumaron resin, terpene resin, petroleum hydrocarbon resin (synthetic polyterpene resin, aromatic hydrocarbon resin, alicyclic hydrocarbon resin, unsaturated hydrocarbon resin, polybutene resin, Examples include those using an adhesive layer in which a tackifier is blended with a general resin such as a liquid rubber (liquid rubber, etc.) or a rosin resin.

The lid of the present invention according to claim 2 is obtained by removing the container portion from the easy-open container according to claim 1, and has a structure in which the bonding layer can be fixed to the periphery of the opening of the container.

FIG. 3(a) is a plan view of this lid, and FIG. 3(b) is a sectional view of the lid. The layer structure is similar to that shown in FIG. 2(a). FIG. 4 is a sectional view of an example in which the grip portion is separate from the lid member.

FIGS. 5 and 6 are cross-sectional views showing other embodiments of the easy-to-open container and lid of the present invention. In FIG. 5, a bonding layer is formed in advance on the container flange, and the lid material is attached to this without bonding. FIG. 6 is a cross-sectional view showing a case in which a packaging container is formed by providing a portion and strongly adhering it by heat sealing or the like, and FIG.

The container of the present invention has excellent sealing properties, can prevent oxidation, discoloration, and invasion of bacteria, and has excellent moisture-proofing, drying-proofing, fragrance-proofing, and rust-proofing properties, so it can be used for food, medicine, and medicine paper packaging. , tape, disinfectant gauze, agricultural chemicals, medical instruments, packaging for surfboard parts, etc.

〔Example〕

Examples of the present invention will be described below, but the present invention is not limited thereto.

In Figure 2, 5: Polypropylene (manufactured by Idemitsu Petrochemical ■, Idemitsu Polypro ElooG) 80% by weight Low-density polyethylene (manufactured by Toyo Soda Kogyo ■, Petrocene 172) 20% by weight 3: Same as above 4: High-density polyethylene (Idemitsu Petroleum) (manufactured by Kagaku ■, Idemitsu polyethylene 540B) A coextruded sheet consisting of 3.4 layers with an inner diameter of 50 mm so that the layer thickness was 5/3/4 = 200 μ/150 μ and 150 μ.
A lid was manufactured by punching out an annular shape of φ and heat-sealing it to the sheet 5 so that t=2 mm.

Next, a high-density polyethylene container (0.5 L) obtained by blow molding was filled with water, and the lid was attached to the flange of the container by heating from above and below to obtain a sealed packaging container.

(Effects of the Invention) The container and lid of the present invention have excellent unsealability, pressure resistance, and sealability. Furthermore, it can be applied to a variety of containers such as trays, cups, and bottles, and the lid can be standardized.

Furthermore, it does not require special processing and has excellent productivity.

[Brief explanation of the drawing]

FIG. 1 is a front view of an embodiment of the easily openable sealed container of the present invention, with a portion thereof being shown as a sectional view. 2nd (a), 2nd (
b), FIG. 2(C) is a sectional view showing the state of adhesion between the lid and the container flange in FIG. 1, and FIG. 3(a) is a plan view of one embodiment of the lid, and FIG. 3(b) 4 is a sectional view of another embodiment of the lid, FIG. 5 is a sectional view of another embodiment of the container, and the fourth diagram is a sectional view of another embodiment of the lid. Explanation of symbols 1. Container flange 2. Lid material 3, bonding layer 4. bonding layer

Claims (1)

[Scope of Claims] 1. A packaging container formed by adhering a container opening periphery, a lid material, and a bonding layer consisting of at least two layers, wherein a layer bond between the container opening periphery and the bonding layer formed by these is provided. Adhesion strength, interlayer adhesion between the bonding layers, and interlayer adhesion between the bonding layer and the lid material should be set to a size that makes it easy to peel off when the lid material is opened, and the remaining interlayers should be set to a size that is difficult to peel off. At the same time, the adhesion strength is set to 0.0 mm from the inner edge between one of the remaining layers.
An easy-open packaging container characterized by having an annular non-adhesive portion of 5 mm or more. 2. A lid formed by adhering a lid material and a bonding layer consisting of at least two layers, and either one of the interlayer adhesive force between the bonding layers formed by these and the adhesive force between the bonding layer and the lid material. The adhesive strength is such that it is easy to peel off when the lid material is opened, and the other adhesive strength is difficult to peel off, and a ring-shaped non-adhesive part is provided between the layers having high adhesive strength by 0.5 mm or more from the inner edge, An easy-to-open lid characterized in that the bonding layer can be fixed to the periphery of the opening of the container.