JP2550598Y2 - Metal foil container with visible contents - Google Patents

Description

[Detailed description of the invention]

[0001]

Industrial Applicability The present invention can be stored for a long time in oxygen tight, and can be used to view the contents heated by an oven toaster or a microwave oven. For example, distribution and storage for foods such as frozen foods and tsukudani. The present invention relates to a metal foil container suitable for:

[0002]

2. Description of the Related Art Conventionally, an oven container (a heat-resistant metal foil container which can be heat-sealed and which can be heated using an oven toaster or a microwave oven, etc.) which is sold with food or the like is used. These are mainly made by baking and coating a metal foil with a polypropylene resin graft-modified with an epoxy resin and maleic anhydride, and then cold-drawn deeply.) To withstand, a metal foil composite laminated sheet whose sealing surface is made of a polyolefin-based resin or hot melt is used to enhance oxygen barrier properties and block moisture intrusion. Since the lid is also made of metal foil, it has excellent properties for long-term storage, oxygen barrier properties, and prevention of moisture infiltration. A problem arises in that it is not possible to know the status of the contents until the process is completed.

[0003]

SUMMARY OF THE INVENTION The present invention relates to an oven in which the contents of a container are visible while maintaining the excellent retort resistance, long-term storage, oxygen barrier properties, and moisture penetration resistance of the conventional metal foil container. The purpose is to develop a container that can be heated in a toaster or microwave oven.

[0004]

Means for Solving the Problems The present invention achieves the above object,
A container body made of metal foil by deep drawing with a flange for sealing, and a CPP of 100 to 300 μm from the surface
A lid consisting of a flange capable of heat-sealing a composite laminated sheet composed of / adhesive / oxygen-barrier film / adhesive / olefin-based sealant to the flange of the container body and a flat portion fitted into the upper opening of the container. We succeeded by developing a container that can see the contents characterized by combining the body.

Hereinafter, the present invention will be described with reference to the drawings. FIG. 1 is an external view of a metal foil container according to the present invention, and FIG. 2 is a sectional view of a lid. That is, in the present invention, the container body 2 made of metal foil is mainly formed by baking and coating an aluminum foil having a thickness of about 80 to 150 μm with polypropylene that has been graft-modified with an epoxy resin and maleic anhydride, so that the acid or alkali of the food to be the contents is obtained. Alternatively, the container is a deep-drawing container using a metal foil coated with protection so as not to corrode the metal foil even during storage for a long time with salt or the like even when heated, and provided with a flange portion for sealing. The outer surface of the container is usually printed with heat-resistant ink.

The lid 3 is made by processing a composite sheet comprising CPP (casting polypropylene film) 11 / adhesive 12 / oxygen barrier film 13 / adhesive 14 / olefin sealant 15. Surface CPP1
1 has a thickness of 100 to 300 μm, and adhesives 12 and 14
Is mainly a urethane-based adhesive having a thickness of 3 to 6 μm, and a barrier film 13 of a polyvinylidene chloride film or a saponified ethylene vinyl acetate copolymer film having a thickness of 1 μm.
A composite sheet in which a film having a thickness of about 5 to 40 μm, preferably about 15 to 25 μm, and an olefin-based sealant 15 having a thickness of 20 to 60 μm via an adhesive 14 is further used. As shown in FIG. 2, this composite laminated sheet is formed into a lid 3 having a flange portion 5 capable of being heat-sealed with the flange portion of the container body 2 and a flat portion 4 fitted into the container upper opening portion as shown in FIG.

Although there is no particular limitation on the method of manufacturing the composite sheet, CPP 11 lacks adhesion to the barrier film 13 and must be bonded by dry lamination. Performing a pre-treatment such as a discharge treatment or a primer treatment on the CPP film prior to the bonding is advantageous in the subsequent processing since the bonding strength is improved.

The adhesives 12 and 14 should be selected according to the use of the metal foil container 1. The adhesives 12 and 14 are used for boiling when sterilized by heating at 70 to 100 ° C., for retort when used at 100 to 130 ° C., If a higher temperature is required, it is necessary to use an adhesive for high retort.

The oxygen barrier film is used to prevent the contents of the package from being oxidized or deteriorated by oxygen in the atmosphere or by moisture, so that the transparent but oxygen-barrier vinylidene chloride or ethylene-vinyl acetate copolymer is used. A combined saponified product is used. However, when hot water or steam is used for heat sterilization, a normal ethylene-vinyl acetate copolymer saponified material has a high risk of causing a decrease in barrier properties due to water absorption and whitening of the film. Vinylidene film or heat resistant,
It is preferable to use a saponified ethylene-vinyl acetate copolymer film having excellent retort resistance and transparency (for example, EVAL RT-Grade Kuraray Co., Ltd.).

The olefin-based sealant 13 also needs to be properly used depending on heat resistance (operating temperature). For low-temperature use, a sealant based on ethylene-vinyl acetate copolymer, low-density polyethylene, or the like is used. A sealant based on polyethylene, polypropylene or the like is used.

As a result of heat sealing, the easily peelable polypropylene-based or polyethylene-based sealant has a heat sealing strength of 0.5 to 2.0 kg / 15 mm.
Widths are usually preferred. If the width is not more than 0.5 kg / 15 mm, there is a problem in the sealing property. If the width is not less than 2.0 kg / 15 mm, the opening becomes difficult, and the lid 3 or the container body 2 may be damaged.

The thickness of the CPP is preferably within a range of 100 to 300 μm in order to secure the rigidity and dimensional stability of the lid. The total thickness of the laminated film thus composited is processed by pressure forming or vacuum forming to form a lid 3 with proper sealing (pressure and heat buffering property during heat sealing) and dimensional stability. It is preferable that the thickness be 150 to 400 μm.

The composite sheet is formed into a cover material by ordinary pressure forming or vacuum forming. In packaging, the metal foil container 1 can be filled with contents by an ordinary automatic packaging line and packaged by heat sealing.

[0014]

In the present invention, the metal foil container body 2 and the CPP are used.
/ Adhesive / Oxygen-barrier film / Adhesive / Olefin-based sealant is composed of a lid 3 processed, so that the oxygen-barrier film has an oxygen barrier property, a moisture-resistant property, a long-term storage property, and It was possible to obtain a metal foil container that can be heated as a food container and whose contents can be seen without opening.

Since the lid is not a normal heat-sealed flat lid type but a so-called drop lid type comprising a flange portion and a flat portion, punching and trimming after sealing are not required. The application range is wide, and the application range is further expanded. Further, since the container body of the deep drawing type has a large capacity, it is useful as an airtight container for heating.

[0016]

Example 1 (Example 1) 150 μm of CPP (T-TC of Tocelo Co., Ltd.), 5 μm of dry laminating adhesive (Dainippon Ink Co., Ltd., LX
-747A / KX-75), barrier layer polyvinylidene chloride film 15 µm (Aran Kasei Co., Ltd. Saran-U)
B), dry laminating adhesive 5μm, sealant
A lid was formed by air pressure molding using a laminated body having a thickness of 50 μm (Toray Synthetic Co., Ltd., CF-9501A).
The container main body has a flange portion with an inner diameter of 10 cm in which aluminum foil is coated with modified polypropylene by baking. For the test, these were heat-sealed in an automatic packaging line to ensure a smooth seal, and even if this product was subjected to a retort sterilization treatment, it did not whiten and was transparent, and the packaging was complete, and the soil due to dimensional shrinkage etc. Did not get up.

Example 2 A saponified ethylene-vinyl acetate copolymer was used as a barrier layer instead of a polyvinylidene chloride film.
(Kuraray EVAL RT-grade) was used. A temporary whitening phenomenon was observed immediately after the retort sterilization treatment, but transparency was restored in a short time. The packaging was perfect and no problems occurred.

[0018]

[Effect of the Invention] The metal foil container according to the present invention can be produced at a low cost, and since the type of the container can be automatically packaged by an automatic packaging line by heat sealing, the productivity is high.
Not only has good sealing properties, it is also easy to open, and is an extremely excellent packaging container for foods and the like. In particular, the lid has excellent characteristics such as heat resistance (heat sterilization such as retort sterilization and heating with a microwave oven), oxygen barrier properties and long-term storage, which are excellent properties of metal foil containers using metal foil. Yes, it can be widely used as a packaging container for food etc.

[Brief description of the drawings]

FIG. 1 is an external view of one metal foil container according to the present invention.

FIG. 2 is a sectional view of the lid according to the present invention.

[Description of Signs] 1 Metal foil container 2 Container main body 3 Lid 4 Flat part 5 Flange part 11 CPP 12 Adhesive 13 Oxygen barrier film 14 Adhesive 15 Olefin sealant

Claims (3)

(57) [Scope of request for utility model registration] 1. A container body made of metal foil by deep drawing provided with a flange portion for sealing, and a CPP 10
A composite laminate sheet composed of 0 to 300 μm / adhesive / oxygen barrier film / adhesive / olefin sealant in this order can be heat-sealed to the flange of the container body, and the flat part fitted to the upper opening of the container. A container with visible contents characterized by combining a lid made of 2. The metal foil container according to claim 1, wherein the lid is a transparent lid comprising a flat portion fitted into the upper open portion of the container body and a seal portion heat-sealed at the container body flange. 3. The metal foil container according to claim 1, wherein a polyvinylidene chloride film or a saponified ethylene-vinyl acetate copolymer is used as the oxygen barrier film of the lid.