JPS6340734B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a food and drink packaging container which is internally deoxygenated so that the food and drink contained therein is protected from the effects of oxygen.

In recent years, oxygen absorbers have come to be used to maintain the freshness of foods. This oxygen scavenger reacts with oxygen in the air and fixes it, and by placing it in a container with food and sealing it, it maintains the inside of the container in an oxygen-free state. Foods kept in such an anoxic environment are then protected from the adverse effects of oxygen.

The present invention provides a food and beverage packaging container with a novel structure that utilizes such an oxygen scavenger.

That is, according to the present invention, an oxygen scavenger layer and a fibrous layer composed of a powdered oxygen scavenger are provided between an air-impermeable film and an air-permeable heat-sealable film, and the fibrous layer includes at least the oxygen scavenger layer. A laminate that is interposed between the agent layer and the breathable film and formed as a whole as a single sheet is used as a lid, and the lid is used for eating and drinking with the breathable film side as the bottom surface. An internal deoxidizer that is made by stacking the heat-sealing film surface of the lid on the open end circumference of an airtight container containing the product and heat-compression bonding between the heat-sealing film surface of the lid and the open end circumference of the airtight container to seal the container. A food and beverage packaging container is provided.

To explain the present invention with reference to the drawings, FIG. 1 is a cross-sectional explanatory view of the packaged food and drink container of the present invention, in which A is the lid, B is the container, and C is the contained food.

The lid A used in the present invention has an oxygen scavenger layer interposed between an air-impermeable base film and an air-permeable heat-sealable film together with a fiber layer, and the whole is formed into an integrated sheet. It is. in this case,
The fibrous layer is arranged to exist at least between the oxygen scavenger layer and the breathable film.

2a to 2d are explanatory diagrams showing the cross-sectional structure of the lid sheet A used in the present invention, in which 1 is a non-breathable base film layer, 2 is an oxygen scavenger layer, and 5 and 6 are fibers. Layer 3 is a breathable film layer.

The non-breathable base film layer 1 may be a plastic film, for example, various thermoplastic resin films such as polyester, nylon, polypropylene, polyethylene, etc., or those films subjected to oxygen blocking treatment (polyvinylidene chloride treatment). In addition to laminates of these films, metal films such as aluminum foil, and laminates of aluminum foil and heat-fusible plastic films such as polyethylene are also used. This film provides mechanical strength to the lid A and blocks oxygen permeation from the outside air into the container.

The oxygen scavenger layer 2 may be made of various conventionally known powder oxygen scavengers, such as metal powders such as iron powder or copper powder, hydrosulfite or hydrogen sulfite, or
Various oxygen scavenging active substances are applied, such as inorganic compounds such as iron compounds and organic compounds such as pyrogallol, alone or in the form of mixtures with other adjuvants. A preferred oxygen scavenger is iron powder. These oxygen scavengers are fine particles with a particle size of 0.5 mm or less, usually 150 μm or less, and easily react with oxygen in the air due to the catalytic action of water vapor permeating from the outside or moisture added in advance.

The fiber layers 5 and 6 include various sheet-like materials formed from natural and synthetic fibers such as paper, nonwoven fabrics, woven fabrics, and net-like materials. Preferably, a highly flexible material with fine voids such as thin paper, rayon paper, or nonwoven fabric is used. This fiber layer relaxes the bond between the breathable film layer 3 and the oxygen scavenger layer 2, forms fine spaces between the breathable film layer 3 and the oxygen scavenger layer 2, and The oxygen absorbing reaction in the oxygen absorbing agent 2 is facilitated by accelerating the diffusion of oxygen passing through the oxygen absorbing layer 3 into the oxygen absorbing agent layer 2.

The heat-sealable breathable film 3 is usually a plastic film made of polyethylene or the like with pores (so-called perforated polyethylene), or a film that has air permeability (oxygen permeability) but does not allow water to pass through, such as porous plastic. Examples include breathable films such as film and paper whose surfaces have been treated to make them water repellent. In the drawings, the breathable film 3 is made of perforated polyester, and 4 indicates the perforated portions thereof. This breathable film layer protects the oxygen scavenger layer and provides mechanical strength and heat sealability to the lid.

In FIG. 2, X indicates a heat-sealed portion that is thermocompression bonded to the circumferential surface of the opening end of the container.

Figure 2a shows an example in which a fiber layer 5 is interposed between the oxygen scavenger layer 2 and the breathable film layer 3;
Figure b shows an example in which fiber layers 6 and 5 are interposed between the non-breathable film layer 1 and the oxygen scavenger layer 2 and between the oxygen scavenger layer 2 and the breathable film layer 3, respectively. Fig. 2c shows an example in which the oxygen scavenger layer 2 is present in a part (center) of the lid sheet surface, and Fig. 2d shows an example in which the oxygen scavenger layer 2 is present in a part (center) of the lid sheet surface. The following is an example where the image is located in the area and the rest of the area is transparent.

When creating a laminated film for the lid in the present invention, a liquid adhesive can be used to bond each layer. It is preferable to use a polyethylene film or the like for pressure bonding by a dry lamination method. When each layer is joined by such a dry lamination method, the air permeability between each layer is somewhat inhibited by the use of the film, but this film is cast extremely thinly by pressing during lamination, and in some cases Since it becomes a discontinuous film body, its breathability poses no practical problem.

The bonding of the oxygen scavenger layer to the base film 1 is as follows:
In addition to the above-mentioned method, it can also be formed by heating the base film to soften it, dispersing an oxygen scavenger on its surface, and pressing it. Alternatively, the oxygen scavenger layer 2 may be dispersed and bonded in advance on the surface of the fiber layer 5 or between the fiber layers 5 and 6, and then bonded to the impermeable film layer 1 as described above. In this case, the oxygen scavenger is dispersed on the fiber layer surface by dropping dry oxygen scavenger particles directly onto the fiber layer surface, or by mixing the oxygen scavenger particles with a liquid such as water or alcohol together with an appropriate thickener to form a paste. This can be done by applying this paste to the fiber layer surface. If the layer thickness of the oxygen scavenger to be dispersed is too thick, the flexibility of the resulting laminated sheet may be significantly impaired.
In addition, since bonding with the fiber layer becomes difficult, it is necessary to select an appropriate material, but in general, a thin layer, for example, a single particle layer or a thickness of 2 to 3 particles, is formed on the fiber layer. It is better to disperse.

In order to create a packaged food/drink storage container according to the present invention, as shown in FIG. The lid is placed on top with its heat-sealable film 3 side facing down, and the heat-sealed portion X of the periphery of the lid and the peripheral surface Y of the open end of the container are
Thermo-compression bonding is performed between the two. The container in which the lid A is thermocompressed to the opening in this way is completely sealed, and the oxygen inside the container reacts with the deoxidizing action of the oxygen scavenger layer 2 present in the lid A. The substance is immobilized, and the inside of the container is maintained in a substantially anoxic state (oxygen concentration of 1% or less). That is, the oxygen in the container diffuses through the breathable film 3 and the fiber layer 5, comes into contact with the oxygen scavenger layer 2, and is removed by the oxygen scavenger layer 2.

The container B used in the present invention may be of various shapes such as a tray, a cup, or a bottle as long as the peripheral surface of its opening end can be heat-sealed. Also, what to put in the container:
In addition to solid or pasty foods, liquid beverages may be used, and the type thereof is not limited.

Next, the present invention will be explained in more detail with reference to Examples.

Example 1 Oxygen scavenger particles (iron powder treated with dilute hydrochloric acid) with a particle size of about 100 mesh were dispersed on the surface of a nonwoven fabric with a thickness of about 0.2 mm so that the base of the nonwoven fabric was somewhat visible, and then Polyethylene film (thickness
A composite film of 40μ) and a nylon film (thickness 25μ) was stacked with the polyethylene film side facing downward, and the whole was crimped using a hot plate.

Next, a polyethylene film having micropores of 40 μm in thickness was thermocompression bonded to the back surface (nonwoven fabric surface) of the oxygen absorbing sheet thus obtained to obtain a heat-sealable sheet.

Next, prepare a sealed tray whose inner surface has been treated with oxygen-blocking processing (polyvinylidene chloride processing), and after storing the cut rice cakes in this tray, insert the oxygen-absorbing sheet obtained above.
The heat-sealed surface was placed on the open end circumferential surface of the sealing tray, and the circumference was heat-sealed for sealing. After leaving this thing for 40 hours, the oxygen concentration inside it was measured and was confirmed to be 1% or more.

Example 2 For a laminated film of nylon film (thickness 25μ) and polyethylene film (thickness 40μ), an adhesive was applied to the surface of the polyethylene film, and an oxygen scavenger (treated with iron powder and diluted hydrochloric acid) was applied to the coated surface. (dried) were dispersed in a layer and pressed together.

Next, apply adhesive to the perforated polyfilm (polyethylene thickness 50μ) with tissue paper bonded to the surface.
The coated surface was overlapped with the oxygen scavenger surface and pressed together.

The thus obtained laminated film was used as a lid for a food storage container in the same manner as in Example 1, and good results were obtained.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view of the food/beverage storage container of the present invention, FIGS. 2 a to d are cross-sectional explanatory views of the lid, and FIG. 3 is an explanatory cross-sectional view of the sealing container. A...Lid, B...Container, C...Food and drink, 1...
...Non-breathable film layer, 2...Oxygen scavenger layer, 3...
... Heat-sealable breathable film, 4... Holes,
5, 6... fiber layer.

Claims (1)

[Claims] 1. An oxygen scavenger layer and a fibrous layer composed of a powdered oxygen scavenger are placed between a non-breathable film and a breathable, heat-sealable film. A laminate interposed between the film and the whole formed as an integral seal is used as a lid, and
This lid is stacked on the open end circumferential surface of an airtight container containing food or drink with its breathable film surface as the lower surface, and the heat sheet film surface of the lid is placed on the open end circumferential surface of the airtight container. A food and beverage packaging container with internal deoxygenation, which is made by heat-pressing the container and sealing the container.