JPH0958689A - Container made of styrene-based resin foam sheet with mouth covered - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a safe container made of a styrene-based resin foam sheet by heat-molding the styrene-based resin foam sheet wherein a sharp edge of a mouth cut part of the container punched with the mouth left may not be in direct contact with lips or the like, while a surface of a seal lid can be prevented from being split at the time of unsealing the lid, that is, injury of the lips or fingers can be prevented and fitness to the lips is good. SOLUTION: A container 10 is formed in a manner that after a container body 11 is molded by heat-molding a styrene-based resin foam sheet, the sheet is cut with a mouth 13 swelling outward around an opening of the container body left, wherein at least an upper face 15 and a cut face 14 of the mouth are covered by a heat-shrinkable film 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container made of a styrenic resin foam sheet having a mouth portion used for food packaging or tableware when eating. More specifically, the container body is heat-molded using a styrene resin foam sheet or a laminated styrene resin foam sheet obtained by laminating a styrene resin foam sheet and a thermoplastic resin film, and the cut mouth portion of the styrene resin foam sheet is heat-shrinkable. It relates to a container covered with a film.

[0002]

2. Description of the Related Art A container produced by thermoforming a styrene resin foam sheet or a laminated styrene resin foam sheet obtained by laminating a non-foamed thermoplastic resin film on a styrene resin foam sheet has excellent heat insulation and light weight. In addition to its cleanliness and low cost, when the thermoplastic resin film is molded to the outer surface, container strength is improved and the surface becomes smooth, enabling curved surface printing. It is used in large quantities in instant ramen containers, etc., taking into account such features as

A container made of a styrene-based resin foam sheet is formed by heating a styrene-based resin foam sheet and sending it between male and female molds of a molding machine to heat-mold the container body, and then to apply the container around the opening of the container body. It is punched out with a trimming blade, leaving the mouth protruding toward one side, and made into individual containers as products. That is, in such a container, the punching cut surface is the end surface of the mouth.

However, when the mouth of the container is punched out with a trimming blade, the end face of the mouth, which is the cut surface, has sharp corners.
Therefore, it cannot be denied that not only the mouth feels uncomfortable when touching the mouth of the container, but also the lip may be lacerated at the edge of the cut surface when the lip is intentionally rubbed strongly against the mouth by mistake. In addition, the possibility of hurting fingers when handling a container cannot be denied. In particular, a container formed by molding a laminated styrene resin foam sheet has a styrene-based resin film layer with a hard cut surface (container mouth) due to the difference in hardness between the styrene resin foam sheet layer and the laminated thermoplastic resin film layer. The above-mentioned problem is serious because the resin foam sheet layer is projected to the outside and the cut surface of the resin film becomes sharper.

Further, when a seal lid is attached to the seal surface on the upper surface of the mouth of the container such as an instant ramen container, when the seal lid is turned over, the surface cells of the container are peeled off from the cut surface side by the seal lid and the surface is bamboo grass. There is a case that it bounces and becomes unsightly. This tendency is more likely to occur because the drawing ratio represented by the depth of the container / inner diameter of the mouth is as high as 0.8 or more, and the deeper the container, the more the styrene-based resin foam sheet is stretched and weakened during molding. Of.

[0006]

SUMMARY OF THE INVENTION In view of the above situation, the present invention prevents the sharp edge of the mouth cut portion of the container from directly touching the lips or the like, and prevents the surface of the seal lid from blistering when the seal lid is turned over. As a result of diligent studies on an industrially easy method, it is possible to prevent tears on the lips and fingers by covering the mouth with a heat-shrinkable film, and to make a safe styrenic resin foam sheet with a pleasant texture. The purpose is to provide a container.

[0007]

In order to solve the above-mentioned problems, according to the present invention, a styrene resin foam sheet is heat-molded to mold a container body, and then the container body is projected outwardly around the opening. A container formed by cutting and leaving the mouth or a laminated styrene resin foam sheet in which a styrene resin foam sheet and a thermoplastic resin film are laminated is heat-molded so that the resin film is the outer surface to mold the container body. After that, the container is formed by cutting while leaving an outwardly projecting mouth around the opening of the container body, and a mouth formed by coating at least the upper surface and the cut surface of the mouth with a heat-shrinkable film. A container made of a styrene-based resin foam sheet having a coated portion is provided. Thus, by covering at least the upper surface and the cut surface of the mouth of the container with the heat-shrinkable film, the edge of the cut surface is covered with the heat-shrinkable film, so that the edge directly touches the lips and the like. It is possible to prevent tears on the lips and the like, and to improve the mouth feel, and also to prevent blistering even if the seal lid attached to the upper surface of the mouth, which is the seal surface, is flipped over.

Here, if the container is a deep-type container having a drawing ratio of 0.8 or more, which is expressed by depth / inner diameter, the styrene resin foam sheet is stretched and weakened at the time of molding. The effect of covering the part becomes more remarkable.

Further, the heat-shrinkable film has a uniaxial heat-shrinkability, the shrinking direction is set along the circumference of the mouth, and the non-shrinking direction is set across the mouth. More preferably. By setting the shrinking direction of the heat-shrinkable film in this manner, the width in the direction crossing the mouth of the heat-shrinkable film does not change significantly before and after heat shrinking, so that the upper surface and the cut surface of the mouth are surely secured. It is possible to coat. Further, the heat-shrinkable film heat-shrinks in the direction along the periphery of the mouth portion, and the film tightens the mouth portion, so that it also has a function of reinforcing the mouth portion.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The container made of a styrene resin foam sheet according to the present invention means that a styrene resin foam sheet is heat-molded to mold a container body, and then outwardly around the opening of the container body. It is a container formed by cutting with the protruding mouth remaining. Further, after using a laminated styrene resin foam sheet obtained by laminating a styrene resin foam sheet and a non-foamed thermoplastic resin film, the resin film is heat-molded so that the outer surface is formed to mold the container body, The same applies to a container formed by cutting while leaving an opening protruding outward around the opening of the container body.

The styrene-based resin foamed sheet is a polystyrene resin, a copolymer resin of styrene and maleic anhydride, methacrylic acid or the like, a mixed resin of these resins, or a mixture of these polystyrene-based resins and polyphenylene oxide or the like. The resin is kneaded with a foaming agent such as butane or freon by an extruder and then extruded and foamed to form a sheet. In addition, the laminated styrene resin foam sheet includes polystyrene resin, polystyrene resin such as high-impact styrene resin, olefin resin such as polyethylene and polypropylene, polyvinylidene chloride, polyvinyl alcohol, etc. It is a laminate of thermoplastic resin films such as the gas barrier resin. Here, as a method of laminating and laminating a thermoplastic resin film on a styrene-based resin foam sheet, a method of hanging and laminating a film resin on a styrene-based resin foam sheet, a method of directly laminating a resin film by heat, and There is a method of laminating a resin film via an adhesive or the like.

The heat-shrinkable film used in the present invention may be a commonly used one, and the material is a stretched thermoplastic resin such as polystyrene, polyethylene, polypropylene, vinyl chloride, polyethylene terephthalate or nylon. It is preferable that the heat shrinkability in one axis direction (X axis direction) is large and the heat shrinkability in the other axis direction (Y axis direction) is small. The thickness is not particularly limited, but is 15 to 50 μm
Is appropriate.

A method of manufacturing the container 10 from the styrene resin foam sheet will be briefly described with reference to FIG.
First, a styrene resin foam sheet 1 wound in a roll shape
Is heated in the heating furnace 2 to be secondarily foamed, and then the container body 11 is molded by the male and female molds 3. At the time of this molding, the inside of the male and female mold 3 is decompressed by the vacuum evacuation means 4 to enhance the transferability of the mold shape. After this container body 11 is molded, the mouth 13 protruding outward from the opening 12 of the container body 11 is left with an automatic punching machine 5 equipped with a punching blade or a Thomson blade or the like from the styrene resin foam sheet 1. Punching out into individual containers 10. An example of the container 10 thus obtained is shown in FIG. 2, and reference numeral 14 in the drawing denotes a cut surface punched by the automatic punching machine 5. The container 10 shown in FIG. 2 is a deep container having a drawing ratio of 0.8 or more, which is represented by the depth of the opening 12 / the inner diameter, and is a shape in which the effects of the present invention are most effectively exhibited.

Therefore, according to the present invention, as shown in FIGS. 3 to 5, at least the upper surface 15 and the cutting surface 14 of the mouth portion including the mouth 13 are covered with the heat-shrinkable film 16.
The aspect of coating the mouth of the heat-shrinkable film 16 is
There are the following. One is to cover only the upper surface 15 and the cutting surface 14 of the mouth 13 as shown in FIG. 3, and to cover the entire upper surface 15 (FIG. 3 (a)).
And a part of the upper surface 15 is covered (FIG. 3 (b)). The second one covers the upper surface 15 of the mouth 13 and the cut surface 14 and the lower surface 17 as shown in FIG. 4, and covers the entire upper surface 15 and the lower surface 17 (FIG. 4 (a)).
And a part of the upper surface 15 and the lower surface 17 (FIG. 4 (b)). The third is the mouth 13 as shown in FIG.
Upper surface 15, cutting surface 14 and lower surface 17 of the container body 11
The outer surface 18 and the inner surface 19 are continuously coated over the upper ends thereof. For the purpose of coating the cut surface 14 with the heat-shrinkable film 16, the coating mode shown in FIG. 3 is sufficient, but in terms of the peel strength of the heat-shrinkable film 16, the coating shown in FIG. 4 or FIG. Is preferable. Here, in the present invention, the “mouth portion” means a range including the mouth 13 and the upper end portion of the container body 11.

The container 10 according to the present invention contains food such as instant noodles inside the container body 11, and a seal lid (not shown) on the surface (sealing surface) of the heat-shrinkable film 16 corresponding to the upper surface 15 of the mouth 13. To be used as a packaging container by pasting it with an adhesive or the like. Then, when eating the food inside, the container 10 is used as tableware by flipping the above-mentioned seal lid, and the lips are applied to the mouth 13 as needed. Therefore, in the present invention, since the heat-shrinkable film 16 covers the mouth of the container 10, the material itself of the styrene-based resin foam sheet 14 does not crumble when flipping the seal lid, and the lip Since it hits the heat-shrinkable film 16, the mouth feels good, and the lips are not torn at the edge of the cut surface 14.

In the container 10 of the present invention, the container 10a may be formed in the same manner as described above by using the laminated styrene resin foam sheet 1a in which the non-foamed thermoplastic resin film 20 is laminated on the styrene resin foam sheet 1. It is possible, and in that case, the thermoplastic resin film 20 is molded so as to be the outer surface of the container 10a. 6 to 8 show a mode in which the mouth portion of the container 10a is covered with the heat-shrinkable film 16, and FIG. 6 covers only the upper surface 15 and the cut surface 14 of the mouth 13, What covers the entire upper surface 15 (FIG. 6 (a)) and that covers a part of the upper surface 15 (FIG. 6 (b)). FIG. 7 shows the upper surface 15 of the mouth 13 and the cut surface 14 and the lower surface. 17 (the lower surface of the thermoplastic resin film 20 corresponding to the mouth 13) and covering the entire upper surface 15 and the lower surface 17 (FIG. 7 (a))
And a part of the upper surface 15 and the lower surface 17 (FIG. 7 (b)). FIG. 8 shows the upper surface 15, the cutting surface 14 and the lower surface 17 of the mouth 13, and the outer surface 18 of the container body 11 (the container body). 11
The surface of the thermoplastic resin film 20) and the upper end of the inner surface 19 are continuously coated. In this case, the embodiment shown in FIGS. 7 and 8 is more preferable because the cut edge of the hard and sharp thermoplastic resin film 20 is covered.

In the method of covering the mouth portion with the heat-shrinkable film 16, the shrinking direction of the heat-shrinkable film 16 is set to the direction along the circumference of the mouth portion, and the non-shrinking direction is set to the direction crossing the mouth portion. Set, wrap around the mouth of the container 10,
Indirect heating such as hot air or radiant heat from a heater or direct heating in which a hot platen is brought into direct contact with a heat-shrinkable film to apply heat to the film for shrink-coating, a ring-shaped film is attached to the upper surface of the mouth, and the film is similarly heated Examples of the method include shrink coating, and various known methods can be applied depending on the shape of the mouth of the container to be coated, the material of the heat-shrinkable film used, the degree of coating, and the like.

In the coating, the coating due to heat shrinkage may not be sufficiently removed, but in some cases, it is more workable to apply the adhesive to the heat shrinkable film and perform the coating operation while adhering it to the mouth of the container. good. Also, in the case of a container that requires gas barrier properties such as moisture permeability, gas may pass through the gap between the container and the covered heat-shrinkable film. Is preferred.

[0019]

[Example] Using a commercially available polypropylene heat-shrinkable film (thickness 30 μm), a cylinder (width 12 mm, applied in the Y-axis direction of the film) adapted to the outer diameter of the container was prepared,
The container was fitted into the mouth of the container and passed through a heating furnace for blowing hot air of 150 ° C. from the side for 5 seconds while rotating the container in the circumferential direction.

The container discharged from the heating furnace had no deformation,
The mouth portion shown in FIG. 4 or FIG.
A container 10 (10a) coated with was obtained. The mouth of the obtained container was rubbed against the lips while rotating, but it did not feel pain in the lips like the container before coating, and slipped smoothly over the lips.

Further, a sealing lid which can be adhered to polypropylene was heat-sealed and sealed to the upper surface of the mouth of the obtained container, and then the sealing lid was turned over.
The seal lid could be turned over without peeling off the upper surface 15 of No. 3.

[0022]

EFFECTS OF THE INVENTION According to the present invention having the above-mentioned contents, by covering the mouth of a container made of a styrenic resin foam sheet with a heat-shrinkable film, the mouth of the container produced in the punching step during manufacturing can be It is possible to provide a safe container in which a sharp cut edge does not directly touch the lips or the like, has a good mouth feel, and does not damage the lips or fingers. When used as a packaging container, a sealing lid is attached to the upper surface of the mouth of the container to close the opening, but when the sealing lid attached to the upper surface of the mouth is turned over, a styrene resin foam sheet layer is formed. The surface cells of No stick to the seal lid and never peel off.

Further, since the mouth of the container is covered with the heat-shrinkable film, the heat-shrinkable film can be applied to the part to cover the container and the film can be easily covered with hot air. No wrinkles are generated on the part and it can be beautifully coated. In addition, colorizing the heat-shrinkable film or using a pattern-printed product can decorate the mouth of a monotonous styrene resin foam sheet container.
It will be a nice looking container.

[Brief description of drawings]

FIG. 1 is a simplified layout view showing a part of a container manufacturing apparatus according to the present invention.

FIG. 2 shows a container according to the present invention, in which (a) is a partially cutaway side view and (b) is a plan view.

FIG. 3 is a partially enlarged cross-sectional view showing a state in which the upper surface and the cut surface of the mouth of a styrene resin foam sheet container are covered with a heat-shrinkable film, (a) shows the entire upper surface,
(b) is a part of the top surface covered.

FIG. 4 is a partially enlarged cross-sectional view showing a state in which the upper surface, the cut surface, and the lower surface of the mouth are covered with a heat-shrinkable film,
(a) covers the entire top and bottom surfaces, and (b) covers a part of the top and bottom surfaces.

FIG. 5 is a partially enlarged cross-sectional view showing a state in which the upper surface, the cut surface and the lower surface of the mouth and the upper ends of the inner and outer surfaces of the container body are covered with a heat-shrinkable film.

FIG. 6 is a partially enlarged cross-sectional view showing a state in which the upper surface and the cut surface of a container made of a laminated styrenic resin foam sheet are covered with a heat-shrinkable film, (a) shows the entire upper surface, In b), a part of the upper surface is covered.

FIG. 7 is a partially enlarged cross-sectional view showing a state in which the upper surface, the cut surface and the lower surface of the mouth are covered with a heat-shrinkable film,
(a) covers the entire top and bottom surfaces, and (b) covers a part of the top and bottom surfaces.

FIG. 8 is a partially enlarged cross-sectional view showing a state in which the upper surface, the cut surface and the lower surface of the mouth and the upper ends of the inner and outer surfaces of the container body are covered with a heat-shrinkable film.

[Explanation of symbols]

 1 Styrene Resin Foam Sheet 1a Laminated Styrene Resin Foam Sheet 2 Heating Furnace 3 Mold 4 Vacuum Evacuation Means 5 Automatic Punching Machine 10, 10a Container 11 Container Body 12 Opening 13 Mouth 14 Cut Surface 15 Upper Surface 16 Heat Shrinkable Film 17 Lower surface 18 Outer surface 19 Inner surface 20 Thermoplastic resin film

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area B29K 105: 02 105: 04 B29L 22:00

Claims (4)

[Claims] 1. A container formed by thermoforming a styrenic resin foam sheet to form a container body, and then cutting the container body while leaving an outwardly projecting mouth around the opening of the container body. A container made of a styrene-based resin foam sheet with a covered mouth, wherein at least the upper surface and the cut surface of the mouth are covered with a heat-shrinkable film. 2. The styrene resin foam sheet coated with a mouth portion according to claim 1, wherein the styrene resin foam sheet is a laminated styrene resin foam sheet having a non-foamed thermoplastic resin film laminated on at least one surface thereof. Container. 3. The styrenic resin coated on the mouth portion according to claim 1 or 2, wherein the shape of the container is a deep container having a drawing ratio of 0.8 or more, which is represented by depth / inner diameter. Foam sheet container. 4. The heat-shrinkable film has a uniaxial heat-shrinkability, the shrinking direction is set along the circumference of the mouth portion, and the non-shrinking direction is set across the mouth portion. A container made of a styrene-based resin foam sheet, which is obtained by coating the mouth portion according to claim 1, 2, or 3.