JPH06286765A - Easy-to-open container - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Providing a container that can be opened neatly when the lid material is to be peeled off and opened by using a barrier film that is transparent and has a thin layer of an inorganic substance with excellent oxygen barrier properties. To do. [Structure] A tray-shaped container body obtained by vacuum forming a multilayer film 5 having a structure of PP / EVOH / PP, an easily peelable heat-adhesive resin layer 3, and a stretched Ny film 7 or 2 having a thickness of 30 μm or more. Barrier film 5, PE formed by vacuum deposition of a thin film of silicon oxide on an axially stretched PET film
The lid member 2 in which T films are sequentially laminated is heat-sealed and hermetically sealed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flange member formed at the opening edge of a plastic container body, in which a lid member is heat-sealed to make it more sealed. Regarding a container that can be opened neatly.

[0002]

2. Description of the Related Art Conventionally, a plastic container body formed by molding a single plastic material or a laminated material mainly made of plastic to form a storage portion for contents and a flange portion at an opening edge, and a heat treatment for the flange portion. A container including a lid member that seals and seals the container body is widely used.

[0003] In this container, contents such as foods and chemicals that are easily affected by oxygen are often stored, and a material having an oxygen barrier property is generally used as a constituent material of the container. For example, as the container body, a saponified product of polypropylene (PP) / ethylene-vinyl acetate copolymer (E
A VOH) / PP multilayer film formed by a method such as vacuum forming is used.
Further, as the lid material, one having a structure of a heat adhesive resin / stretched nylon film (ONy) / polyvinylidene chloride (PVDC) / polyethylene terephthalate (PET) is known. EVOH and PVDC described above are widely used as plastic films having an oxygen barrier property. In addition, as a material having an oxygen barrier property, a metal foil such as an aluminum foil or a vapor deposition film having an aluminum vapor deposition layer formed thereon is used. However, depending on the content, it is required that the inside can be seen through. It may not be possible to use an opaque material such as. In particular, aluminum foil becomes a lump when incinerated, is difficult to dispose of, and is not used because of damage to the incinerator.

Further, the lid material needs to be easily and cleanly peeled off from the container when opened, and a special resin is used as the heat-adhesive resin or the structure for adhering to the container is carefully devised. Many things have been proposed. However, in general, a heat-adhesive resin having an appropriate heat-sealing property and peeling property is used.

By the way, in recent years, since polyvinylidene chloride contains chlorine, when it is incinerated, chlorine gas is released to pollute the atmosphere, so that a material having a structure not using polyvinylidene chloride has been desired.

On the other hand, a barrier film in which a thin film layer of an inorganic substance such as silicon oxide is formed on a base material film such as polyester or nylon has started to be used as a material which is transparent and has an excellent oxygen barrier property.

[0007]

Therefore, it was considered that a lid material satisfying the requirements could be obtained by using the above barrier film instead of PVDC of the conventional lid material. However, as a result of the study conducted by the present inventors, if a barrier film is simply used instead of PVDC, the adhesion strength between the thin film layer of the inorganic substance and the base film is insufficient.
It was found that the thin film layer and the base film may be peeled off from each other, and the opening during use may not be performed properly.

Therefore, the present invention provides a container which can be opened neatly when a lid material is desired to be peeled off and opened by using a barrier film having a thin film layer of an inorganic substance which is transparent and has an excellent oxygen barrier property.

[0009]

Means for Solving the Problems That is, the present invention provides a lid material including an easily peelable heat-adhesive resin layer and a barrier film formed by forming a thin film layer of an inorganic substance on a base film, and a plastic material. A container obtained by heat-sealing a container body to a flange portion formed on the container body, wherein the container body has a thickness of 30 μm between the barrier film and the easily peelable heat-adhesive resin layer.
It is an easy-to-open container characterized by arranging the above stretched nylon film.

[0010]

In the container of the present invention described above, the thin film layer of the inorganic material exhibits an excellent oxygen barrier property, and imparts the oxygen barrier property to the lid member. Since a stretched nylon film of 30 μm or more is arranged between the barrier film of the lid material and the easily peelable heat-adhesive resin layer, the lid material can be cleaned without peeling between the base film and the thin film layer. Can be peeled off.

[0011]

The present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic explanatory view of a container of the present invention, and FIG. 2 is a sectional view showing an example of a lid material used in the present invention.

As shown in FIG. 1, the container A of the present invention comprises a container body 1 and a lid member 2, and the lid member 2 is heat-sealed to a flange portion 11 formed at the opening edge of the container body 1. The container is sealed. The formed storage portion 12 generally stores contents such as foods and chemicals that are easily affected by oxygen. The contents may be directly stored in the container A or may be stored as a package in another packaging container.

As the container body 1 used in the present invention, a commonly used plastic one can be used.
In order to prevent the influence of oxygen on the contents, it is desirable to include a material having an oxygen barrier property. For example, the EVO mentioned above
H is a preferable material because it has excellent oxygen barrier properties and transparency. More specifically, PP / EVOH / PP
It is possible to use those obtained by forming a laminated material such as the above into a tray shape by vacuum forming or the like.

The lid member 2 used in the present invention comprises an easily peelable heat-adhesive resin layer 3, a base film 51 and a thin film layer 4 of an inorganic substance.
And a barrier film 5 formed by forming a stretched nylon film having a thickness of 30 μm or more between them.

The easily peelable heat-adhesive resin layer 3 is a layer that enables the lid member 2 to be heat-sealed to the container body 1, and can be easily peeled from the flange portion 11 when the container is opened. is necessary. As the easily peelable heat-adhesive resin layer 3, a multilayer film that can be opened by delamination or cohesive failure (for example, “CMPS having a three-layer structure of polypropylene”) is used.
-013C ", manufactured by Tohcello Chemical Co., Ltd.) can be used.
The above-mentioned "CMPS-013C" causes cohesive failure between the layers at the time of opening, so that the lid material can be peeled off. In the present invention, the "CMPS-013C" having a thickness of 30 to 50 μm can be preferably used.

A barrier film 5 used in the present invention, which is formed by forming a thin film layer 4 of an inorganic substance on a base film 51.
Is known as a packaging material having excellent oxygen barrier properties and water vapor barrier properties. For example, Japanese Patent Publication No. 53-1295
Japanese Patent Publication No. 3 discloses a barrier film in which a thin film layer of silicon oxide having a thickness of about 1000Å is formed on a polyester film by vacuum vapor deposition. Also in the present invention, a conventionally known barrier film 5 having a thin film layer 4 of an inorganic substance formed thereon can be used.

Base film 51 of barrier film 5
As the film (that is, a film forming a thin film layer of an inorganic substance), a film having a suitability for forming a thin film layer such as polyester, polypropylene, saponified ethylene-vinyl acetate copolymer, nylon, or polyvinyl alcohol can be used. In particular, in the present invention, it is preferable to use a biaxially stretched polyester film or a stretched nylon film as the base material film 51 in order to give the lid member strength (elasticity). The thickness of the base film 51 is usually 10 to 10.
It is 40 μm.

The inorganic substance thin film layer 4 formed on the base film 51 may be any one capable of obtaining an oxygen barrier property, and known inorganic substances such as silicon oxide, magnesium oxide and aluminum oxide are vacuum-deposited. A film having a thickness of 400 to 2000 Å can be used by a method such as sputtering, ion plating, or plasma CVD. The above-mentioned inorganic substances are suitable because they are generally excellent in transparency and oxygen barrier property. Among them, silicon oxide is particularly preferable from the viewpoint of easy thinning, transparency, cost, and safety.

The lid member 2 used in the present invention comprises the above-mentioned easily peelable heat-adhesive resin layer 3 and the barrier film 5, and a stretched nylon film 7 having a thickness of 30 μm or more is arranged between them. is there. That is, by arranging the stretched nylon film 7, the stretched nylon film 7 receives a force applied for peeling, and the base film having the thin film of the inorganic substance formed thereon does not receive an excessive force, that is, The lid member can be peeled off without peeling off the thin film of the inorganic substance and the base film.

The stretched nylon film 7 has a thickness of 30.
A single-layer film having a thickness of at least μm may be used, or the film may have a thickness of at least 30 μm by laminating two or more thin stretched nylon films.

Further, the cover material 2 can be formed with other layers as required. For example, on the outer side of the barrier film 5, an outer layer 6 as a printing substrate such as a biaxially stretched polyethylene terephthalate film, a biaxially stretched polypropylene film, a biaxially stretched nylon film, or a barrier film made of a plastic film or a resin coating. A protective layer for the thin film layer 4 of the inorganic substance 5 may be laminated.

The lid member 2 of the present invention obtained as described above
Are laminated by facing the easily peelable heat-adhesive resin layer 3 to the flange portion 11 of the container body 1 and heat-sealed to seal the container body 1.

<Experiment 1> PP (400 μm) / EVOH
A multilayer film composed of (20 μm) / PP (400 μm) is vacuum-formed and punched out, and the inside dimension of the storage section is 30 vertical.
A tray-shaped container body having a size of 0 mm × width 150 mm × depth 80 mm and a flange width of 10 mm was prepared.

In addition, a 50 μm-thick “CMPS-013C” (trade name, manufactured by Tocello Chemical Co., Ltd.) as an easily peelable heat-adhesive resin layer, a 15 μm-thick stretched nylon film (Emblem ONM: trade name, Unitika) (Made by corporation)
Stretched nylon film layer formed by laminating two layers, thickness 12
A barrier film in which a thin film of silicon oxide (thickness 1000 Å) was formed on a μm biaxially stretched polyethylene terephthalate film by a vacuum deposition method was sequentially laminated by a dry lamination method using an adhesive. Seal side ("CMPS-013C" side)
The thin film layer was made to face) and punched out according to the shape of the container body to obtain the lid material of the present invention.

For comparison, a lid material was prepared in the same manner except that the stretched nylon film was a single layer of a stretched 6-nylon film having a thickness of 25 μm (BCRT: trade name, manufactured by Unitika Ltd.).

Sealing condition: 2
Heat sealing was performed at 20 ° C. for 1 second at 4 kg / cm to prepare a container.

In order to open this container, the end of the lid member was picked and peeled off.
"MPS-013C" caused cohesive failure between layers and could be peeled off neatly. However, in the case of the comparative one, the biaxially stretched polyethylene terephthalate film of the barrier film and the thin film layer of silicon oxide were peeled off during the peeling, and the stretched nylon film and the like were torn off, and "C
There was a defect that MPS-013C ”/ ONy / SiO partially remained in the form of a film.

[0028]

As described above, since the container of the present invention has the above-mentioned structure, it is possible to provide a container which can be opened neatly when the lid member is to be peeled off and opened. Further, since the container of the present invention does not use a material that generates harmful chlorine gas, it does not pollute the environment even when incinerated and is easy to dispose. The lid material of the present invention has excellent oxygen barrier properties, and since the container body can also be made to have excellent oxygen barrier properties, a container having excellent oxygen barrier properties as a whole can be obtained. It is possible to provide a container that is easily affected and is suitable for packaging foods and medicines.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of a container of the present invention.

FIG. 2 is a sectional view showing an example of a lid material used in the present invention.

[Explanation of symbols]

 1 ... Container body 2 ... Lid material 3 ... Easy-peelable heat-adhesive resin layer 4 ... Thin film layer of inorganic substance 5 ... Barrier film 51 ... Base film 5 ... Outer layer film 6 ... Outer layer 7 ... … Stretched nylon film A …… Container

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Keiko Yagi 1-5-1 Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd.

Claims (2)

[Claims] 1. A flange formed on a plastic container body with a lid material made of a laminated material including an easily peelable heat-adhesive resin layer and a barrier film formed by forming a thin film layer of an inorganic substance on a base film. A container which is heat-sealed in a portion, wherein a stretched nylon film having a thickness of 30 μm or more is arranged between the barrier film and the easily peelable heat-adhesive resin layer, and the container is easy to open. 2. The container according to claim 1, wherein the thin film layer of the inorganic substance is a thin film layer of silicon oxide.