JP2586427Y2 - Food containers - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a food container mainly used for selling food such as natto.

[0002]

2. Description of the Related Art In recent years, it has become mainstream that fresh foods such as meat and fish and cooked foods such as prepared foods are sold in synthetic resin trays or lidded containers. ing. Above all, there are many molded articles made of foamed sheets of polystyrene resin from the viewpoints of moldability, heat insulation and low cost.

[0003] These containers are usually discarded as they are after use, but there is a problem that, for example, when odorous foods such as natto or perishable foods are contained therein, if they are discarded as they are, a bad odor drifts from a trash box or the like. . In addition, in the case of natto or the like, it is difficult to wash the container. Therefore, it is troublesome to prepare a separate bag or the like and seal it. Especially when a large number of used containers appear, the treatment is often troublesome.

[0004] Recently, since effective use of resources has been demanded, these containers are also being collected and recycled. However, in this case, the quality of the recycled resin deteriorates due to the dirt remaining in the container, and there is a problem in that the value of the recycled resin is low even if the resin is recycled.

Therefore, in order to solve these problems,
It has been considered that a film layer made of a releasable resin film or the like is laminated on the surface of a base material layer constituting a container, and a soiled film layer is peeled and removed at the time of disposal or collection.

In this case, the adhesive between the film layer such as a film and the substrate layer is an important element. Depending on the type of the adhesive, the adhesive is insufficient or, on the contrary, the adhesive is strong and cannot be peeled off. Disappears. For example, when a solvent-type or emulsion-type adhesive having low adhesive strength is used, bubbles may be generated at the interface during molding from a sheet, and partial peeling such as floating may easily occur. In addition, most of the hot-melt type adhesives generally used generally have a high adhesive strength and cannot be easily peeled off.

In particular, in the case of using a polystyrene-based resin as the base material layer, since the material has good adhesiveness with the adhesive, even if the surface coating layer can be peeled off, the adhesive itself may be used. Are easily left on the surface of the base material, which deteriorates the quality when the base resin is recycled.

[0008] The present invention has been made in view of the above, and as a result of intensive studies on the case of providing a peelable coating layer in a container made of a polystyrene-based resin as a base layer, as a result, the film used for the coating layer By using a specific adhesive in relation to the material, it forms a surface film layer that retains adhesive strength without forming problems and that can be peeled off with an appropriate force without leaving the adhesive itself on the base layer surface This led to the development of an improved food container.

[0009]

In order to solve the above-mentioned problems, the food container of the present invention is obtained by laminating a resin film on the surface of a base material layer made of a polystyrene resin via an adhesive layer and peeling the resin film. A food container formed by forming a surface coating layer as a possible surface and forming the surface coating layer inside, wherein the base material layer and the olefin film or polyester film as the surface coating layer are formed of a hot melt type. When the surface coating layer is peeled off from the base layer,
It is assumed that the adhesive layer is peeled off while being adhered to the surface coating layer, and the peel strength is in the range of 50 to 500 g / 15 mm width.

[0010]

According to the food container having the above structure, the adhesive layer for bonding the substrate layer of the polystyrene resin and the film layer on the surface is a hot-melt type olefin adhesive. It has a moderate adhesive force that does not generate bubbles in the adhesive layer part, and when reuse of the base resin after use, applies a moderate force to the stained surface film layer It can be easily peeled from the layer.

In particular, in the case of the present invention, in addition to using a polyolefin-based film or a polyester-based film as the film layer of the surface coating layer, the olefin-based adhesive is used as the adhesive layer as described above, The agent layer adheres more strongly to the film layer to the substrate layer, and thus, when the surface coating layer is peeled from the substrate layer,
The adhesive layer is peeled off while adhering to the film layer side,
It does not remain in the substrate layer.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a food container according to the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a food container A according to an embodiment of the present invention, and FIG. 2 is a partial sectional view thereof.

In the illustrated food container A, a storage portion 10 having a flange-like edge portion 11 at an opening edge and a corresponding lid portion 20 are integrally connected via a hinge portion 30 such as a V-shaped groove formed by heating and pressing. The cover 20 is provided so as to bend and fit into the opening of the storage unit 10. When this food container A is used for a natto container, small holes 21 for ventilation are provided at required places such as the lid portion 20 and a protective film (not shown) with a ventilation hole is placed on the stored natto. I will

As shown in the figure, the food container A has a polyolefin resin film layer c and a hot melt type olefin adhesive layer b on the surface of a base material layer a made of a polystyrene resin foam sheet. A surface coating layer 1 that can be peeled off by lamination is formed from the laminated sheet material into a container with the surface coating layer 1 inside by means of vacuum, press molding or the like.

The adhesive strength of the olefin-based adhesive layer b is such that the surface coating layer 1 does not partially float or peel during use and molding, but can be peeled off by applying a certain peeling force. The adhesive strength is usually 50 to 500 (g).
/ 15 mm width), preferably 100 to 200 (g / 15 mm
Width). If the peel strength is larger than the above range, it becomes difficult to peel off, and if it is smaller than the above range, in use as a container, floating or peeling is likely to occur, and the commercial value is reduced. Is good.

In the case of the drawing, the flange-like edge 1 of the storage section 10 is shown.
In one corner, a peeling assisting portion 12 having a substantially triangular planar shape and separated by a cutting line 13 is provided. This cut line 13
Is formed with a V-groove or perforated cut or thin portion in the base material layer a so that only the base material layer a can be easily cut by hand along the cut line a. In addition to the above, a part of the edge portion 11 where the film layer c is not adhered may be left, or the film layer c may protrude from the base material layer a.

After the food container A is used, the soiled surface film layer 1 can be peeled off by, for example, the above-mentioned peeling assisting section 1.
2 and cut only the base material layer a along the perforated line 13;
The surface film layer 1 may be peeled off by peeling the film layer c connected to the inner side of the storage portion 10 from the base material layer a, and thereby the film layer c of the surface film layer 1 and the adhesive layer b are peeled off together.

That is, since the polyolefin-based resin film layer c and the olefin-based adhesive layer b are made of the same type of resin, the adhesive layer b is easily bonded and integrated with the film layer c, and the polystyrene-based adhesive layer b is made of polystyrene. Base resin layer a
Therefore, if the film layer c is peeled off, the adhesive layer b adhered thereto is also peeled off and does not remain on the base material layer a.

As the base layer a of the polystyrene resin, a foamed sheet of polystyrene resin alone or styrene such as styrene-maleic anhydride, styrene-acrylic acid, styrene-acrylonitrile, styrene-methyl methacrylate, etc. A foamed sheet or a non-foamed sheet of a heat-resistant polystyrene resin such as a copolymer containing 5 to 40% of other components can be used.

As the olefin-based adhesive layer b, for example, an ethylene-vinyl acetate copolymer is particularly preferably used, but is not limited to this.

As the film layer c, a film of polyethylene such as high-density polyethylene or low-density polyethylene, polypropylene such as unstretched polypropylene or stretched polypropylene, or a polyolefin resin film such as a copolymer mainly composed of ethylene is preferably used. be able to.

As the film layer c of the surface coating layer 1, a film of a polyester resin such as polyethylene terephthalate or polybutylene terephthalate can be used instead of the above-mentioned polyolefin resin film.

Also in this case, the polyester film is
Since it has properties close to those of the olefin-based resin and has good adhesion to the olefin-based adhesive layer b, the film layer c
At the same time, the adhesive layer b can be peeled off without remaining on the base material layer a.

A polyethylene film is adhered to the expanded polystyrene sheet using a hot-melt type ethylene-vinyl acetate copolymer adhesive under the following pressure bonding conditions.
When a peeling test was performed to check whether the adhesive layer remained on the base material layer, no adhesive layer remained at any of the pressure bonding temperatures.

Crimping conditions Temperature: 130 ° C., 135 ° C., 140 ° C., 145 ° C., 15
0 ° C. Time: 0.5 seconds, pressure: 2.0 kg / cm ² .

The form of the container is not limited to that of the illustrated embodiment. For example, the surface coating layer 1 may be provided only on the side of the storage section 10, and the storage section 10 and the lid section 20 may be formed separately. You can also keep.

FIG. 3 shows the bonding of a polyolefin-based film c on which a pattern, a trademark or the like is printed to a base layer a of a polystyrene foam sheet via the olefin-based adhesive layer b with the printing surface side inside. FIG. 2 is a partially enlarged cross-sectional view when the surface coating layer 1 is formed.

In the case of this embodiment, as shown in this figure, since the printing ink layer d is attached to the film layer c and covered with the adhesive layer b, the surface coating layer 1 is peeled off. At this time, it is removed together with the film layer c and the adhesive layer b, and does not remain on the base material layer a at all. Therefore, when the container is collected and regenerated, no impurities remain and a high-quality regenerated resin can be obtained.

[0030]

As described above, according to the food container of the present invention, the film and the adhesive are easily peeled off and removed integrally.

The container after peeling the film is
Since it is easy to collect and regenerate and no impurities such as adhesives and ink remain, a high-quality regenerated resin can be obtained by using this.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing an embodiment of the present invention.

FIG. 2 is a sectional view of the same.

FIG. 3 is a partially enlarged cross-sectional view when a surface film layer is formed using a printed film.

[Explanation of symbols]

 A: Food container a: Base layer b: Adhesive layer c: Film layer d: Ink 1: Surface coating layer 10: Storage section 11: Edge section 12: Peeling auxiliary section 13 ... Cut-off line 20 ... Lid 21 ... Small hole for ventilation 30 ... Hinge

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 4-112028 (JP, U) JP-A 54-149502 (JP, U) JP-A 53-20212 (JP, U) (58) Survey Field (Int.Cl. ⁶ , DB name) B65D 25/14 B65D 1 / 00,1 / 26-1/28

Claims (1)

(57) [Scope of request for utility model registration] 1. A food product obtained by laminating a resin film on the surface of a base material layer made of a polystyrene resin via an adhesive layer to form a peelable surface film layer, and molding the surface film layer inside. A container, wherein the substrate layer and an olefin-based film or a polyester-based film as the surface coating layer are adhered over substantially the entire surface by a hot-melt type olefin-based adhesive, A food container in which the adhesive layer is peeled off while being adhered to the surface coating layer when peeled from the layer, and the peel strength is in the range of 50 to 500 g / 15 mm width.