JPH072242A - Synthetic resin container for food packaging and its manufacture - Google Patents

Abstract

PURPOSE:To provide a novel synthetic resin container and a method for manufacturing it for which waste materials are considerably utilized and yet and inside of the container is visible from outside and special consideration is given to the joining part between the lid and the holding part. CONSTITUTION:A container consists of a lid A having projections and hollows three-dimensionally as required and a holding part B having projections and hollows three-dimensionally as required with a joining part C integrally joining the lid A and the holding part B. The lid A is formed of a sheet of synthetic resin (1) which is formed of a new material and has a high transparency. The holding part B is formed of a sheet of synthetic resin 2 which is formed from waste materials and whose transparency is low. The joining part C consists of flat marginal parts 5a, 5b by which the synthetic resin 1 and the synthetic resin 2 forming the lid A and the holding part B adjoin and are made to adhere to each other by polymerization. Contiguously to the two side parts along the joining part C bending ribs 6, 6 are formed in the lid A and the holding part B respectively to make these bendable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is for packaging foods such as eggs, tofu, meats and seafood for transportation and distribution such as exhibition and sale. Is a container in which a lid and a body of the container are formed so as to be openable and closable, and the lid is formed of a highly transparent synthetic resin sheet formed of a new material, and the body is a waste material. TECHNICAL FIELD The present invention relates to a synthetic resin container for food packaging, which is formed of a synthetic resin sheet having low transparency formed by using, and allows the inside of the container to be seen through from a lid portion, and a manufacturing method thereof.

[0002]

2. Description of the Related Art From the viewpoint of waste disposal and effective use of resources,
It has been demanded to collect and recycle the synthetic resin food container, and the applicant of the present invention responded to this by first taking into account
The invention disclosed in Japanese Patent No. 43132 is proposed.
However, in this prior invention, the synthetic resin sheet made of waste material has a low transparency due to the inclusion of foreign matters and printing ink, and also has a slightly colored opaque property, so that the content see-through effect is Has the drawback of being bad. Therefore, in consideration of this point, the applicant has formed the lid part of the container with an opaque sheet material, the body part with a transparent sheet material, and both of them are polymer-welded so that they can be folded at the flange part. A proposed container was proposed in Japanese Examined Patent Publication No. 39745. In this container, the joint portion of the lid portion and the body portion, which are welded together by polymerization, is formed thin and curved so as to be bendable.

[0003]

However, in such a prior invention, the fusion head must be pressed until the connecting portion becomes thin enough to be bendable, so that it takes time and the flow of the production line is increased. Since the lid part is opened and closed with this thinned connecting part as it is slowed down, it is peeled off to the unfused edge part of the flange piece polymerized by the pulling or bending action that occurs during opening and closing. There is a problem that a phenomenon occurs and the appearance becomes ugly.

In view of the above-mentioned conventional technique, a first object of the present invention is to form a synthetic resin sheet material of a new material having a high transparency only on the lid, and to make the body a synthetic resin having a low transparency due to a waste material. By forming it with a sheet, it is possible to easily check the state of the food stored inside the container from the outside while aiming to effectively use the waste material, and at the connecting part between the lid part and the body part. It is an object of the present invention to provide a container in which the manufacturing time can be shortened, the flow of the production line can be smoothly advanced, and the appearance of the container is not damaged by adding consideration.

Further, a second object of the present invention is such a container, but in the production thereof, the efficiency is the same as in the case of producing the container by using a raw material sheet made of only a new material for the entire container. An object of the present invention is to provide a novel manufacturing method that can be manufactured well.

[0006]

In order to achieve the above-mentioned first object, a synthetic resin container for food packaging according to the present invention has a lid (A) having a required uneven three-dimensional shape and a required three-dimensional shape. A container in which a body (B) having an uneven three-dimensional shape is integrally connected by a connecting part (C), and the lid part (A) is made of a new material and has a high transparency. (1), the body (B) is made of a low transparency synthetic resin sheet material (2) formed by using waste material, and the connecting portion (C) is a lid portion.
(A) and the synthetic resin material forming the body (B) (1), formed by polymerizing and adhering adjacent flat side edge portions (5a), (5b) of (2), the connecting portion ( The structure is such that the lid (A) and the body (B) are formed with folding ribs (6) and (6) which are bendable adjacent to both sides along the width direction of (C). is there.

The manufacturing method of the present invention for achieving the second object is a belt-shaped synthetic resin sheet material (1) having a high transparency formed by using a new material and a low transparency formed by using a waste material. A step of aligning and pulling out the strip-shaped synthetic resin sheet material (2) in parallel, and forming the required concavo-convex shape on these synthetic resin sheet materials (1) and (2) and flat sides along side edges adjacent to each other. Edges (5a), (5b) and this flat side edge
(5a), a step of forming bending ribs (6), (6) along the lengthwise direction of the side edge portions at the base end portions of (5b), and a synthetic resin sheet material (1), (2) ) Flat side edge portions (5a), (5b) are polymerized and adhered to each other, and the uncut container forming strip (8) continuously molded in this manner is cut into a single container (K). And the steps of:

The synthetic resin sheet material (1) using new material and the synthetic resin sheet material (2) using waste material according to the present invention are formed separately or by extrusion from one synthetic resin extruder. Are continuously transferred to the processing step, or those formed in advance are supplied to the processing step. The sheet-shaped material extruded from the extruder can be made into a material having high strength for its thickness by adding a stretching step and stretching. In this case, it is preferable to make the extrusion thickness from the die in the extruder thicker in consideration of the fact that the original sheet becomes thinner in the stretching step.

[0009]

[Function] In the container constructed as described above, only the lid portion (A) is made of a new synthetic resin sheet material having a high transparency, and the body portion (B) is made of a low transparency synthetic resin sheet made of a waste material. As a result, it is possible to obtain a container similar to the new material, which enables effective utilization of the waste material and allows the state of the stored food inside the container to be easily seen through from the outside. Also, the connecting part (C) between the lid part (A) and the body part (B)
Bending ribs (6) and (6) are formed on the lid part (A) and the body part (B) adjacent to both side parts along the width direction of
The lid (A) is opened and closed via the bending ribs (6) and (6) so that the pulling force and the bending repulsive force generated during the rotation are not directly applied to the connecting portion (C). There is no possibility that the overlapping edge portion or the unbonded portion of the connecting portion (C) peels off and the appearance of the container is impaired. In addition, according to the present invention, the manufacturing process described above allows the manufacturing time to be shortened and the flow of the production line to proceed smoothly.

[0010]

EXAMPLES A method for manufacturing a container according to the present invention will be described below based on the examples shown in FIGS. From the two horizontal die (D1) (D1) of the synthetic resin extruder, molten colorless transparent new material polystyrene resin is extruded, and two unstretched new synthetic resin sheet materials with a small width and high transparency (1) (1) is extruded into a strip shape. From another wide die (D2) arranged between these dies (D1) (D1), molten opaque waste material polystyrene resin is extruded, and wide and opaque unstretched waste material synthetic resin sheet material (2 ) Is extruded into a strip shape. In this example, the new synthetic resin sheet material (1)
The width of (1) is 1 in the length direction when the lid (A) of the molded container is
The width of the waste synthetic resin sheet material (2) is set so that it can be molded sequentially in a line, and the width of the container body (B) to be molded
Are set to a dimension that allows them to be sequentially molded in a state of being arranged in two rows in the length direction. The sheet materials (1) and (2) extruded from these dies are drawn by the drawing rollers (3a) and (3b) to a predetermined thickness, for example, a thickness of about 0.25 mm, and sent to the molding machine (4).

The sheet materials (1), (1) and (2) sent to the molding machine (4) are formed with irregular shapes corresponding to the lid (A) and body (B) of the container, respectively. At the same time as this molding, the sheet material
A connecting portion at the side edges where (1) and the sheet material (2) face each other.
(C) forming a flat side edge portion (5a) (5b), and bending along the length direction of the flat side edge portion (5a) (5b) at the base end thereof. Possible folding ribs (6) (6) are formed. The molding machine (4) consists of a pair of upper and lower molds (4a) (4b) for vacuum forming or blow molding, and both molds open and close while moving synchronously along the sheet material advancing direction. The molding operation is performed by repeating the operation of returning to the original position.

Next, the sheet materials (1), (1) and (2) on which the required unevenness was formed were polymerized between the adjacent flat side edge portions (5a) and (5b) and heated appropriately. It is passed between the upper and lower joining rollers (7a) and (7b), and the two are fused and joined to form a joint (C). In this embodiment, the upper joining roller
By forming (7a) by two thin flat gears, fusion welding is performed by an array of intermittent dot joining in two rows, but by changing the shape of the upper joining roller (7a), For example, it is possible to perform fusion splicing in a staggered arrangement as shown in FIG. 6, an arrangement of continuous horizontal lines as shown in FIG. 7, or an arrangement of two rows in a line, and further to make the upper and lower joining rollers flat. It may be possible to adhere the entire surface by forming it on the surface.

Finally, the thus-formed uncut container strip (8) is transferred to the cutting machine (9) to cut between the individual containers of the container group connected in the transverse direction and the traveling direction. And separate it into a single container (K). The cutting machine (9) is composed of a blade die and a receiving die, but may be a high-frequency fusing type or other type. Separated individual container (K)
Are sent to a packing device through a chute, a transfer conveyor, and the like (not shown), and are packed in a predetermined number of boxes.

In this embodiment, two rows of containers are shown as being molded at the same time. However, the number of molding rows of containers is two.
It does not have to be a row at all, it may be at least one row, 2
Needless to say, the molding can be performed in an appropriate number of rows or more, for example, three rows or five rows, which corresponds to the size of the manufacturing apparatus.

3 and 4 show an example of a container manufactured by the above method. The container of the embodiment shown here is shaped to accommodate 3 eggs × 2 rows = 6 eggs, but of course the number is not specified. The container is made of a new material and has a high transparency synthetic resin sheet material (1)
The lid portion (A) formed by (1) and the body portion (B) formed of a synthetic resin sheet material (2) having low transparency formed by using a waste material are connected by a connecting portion (C). This connecting part (C) has flat side edge parts (5a) (5b) adjacent to each other of the synthetic resin materials (1) and (2) forming the lid part (A) and the body part (B) with an appropriate width. Bending ribs (6) (6) which are formed by polymerizing and adhering to each other, and are foldable to the lid part (A) and the body part (B) adjacent to both side parts along the width direction of the connecting part (C). 6) has been formed.

In the container constructed as described above, the lid portion
By forming only (A) with a new synthetic resin sheet material with high transparency and forming the body (B) with a synthetic resin sheet with low transparency due to waste material, it is possible to effectively use the waste material. It is possible to obtain a container similar to the new material that allows the state of the food contained in the container to be easily seen from the outside. Further, the lid portion is adjacent to both side portions along the width direction of the connecting portion (C) between the lid portion (A) and the body portion (B).
Since the bending ribs (6) and (6) are formed on (A) and the body (B), the lid can be opened and closed to rotate via the bending ribs (6) and (6). The pulling force and bending repulsive force that occur at the time of joining
(C) is not directly loaded and therefore the joint (C)
The polymerized edge portion and the non-adhered portion do not peel off and impair the appearance of the container.

The container shown in FIGS. 3 and 4 is formed so that when the lid (A) is closed to the body (B), the tip end of the container is tilted so that it is inclined downward. However, as shown in FIG. 9 and FIG. 10, for example, the lid (A) and the body
The contacting step portions (10) and (10) may be formed on the contact surface of (B) so that the contacting step portions (10) and (10) are closed in a parallel posture.

Although the representative embodiments of the present invention have been described above, the present invention is not necessarily limited to the structures of the above embodiments. For example, by making the uneven shape of the molding machine (4) different, the lid portion (A) and the body portion (B) can be made into an uneven shape suitable for accommodating other foods. . Further, the joining of the connecting portion (C) is not limited to the method of heat fusion using the joining roller described above, and may be a joining means using high frequency, ultrasonic waves or laser. In addition, it is needless to say that the present invention can be appropriately modified and implemented within a range that has the constituent features and has an effect.

[0019]

As is apparent from the above description, in the container of the present invention, only the lid (A) is made of a highly transparent new synthetic resin sheet material, and the body (B) is made of waste material. By forming a synthetic resin sheet with low transparency, it is possible to effectively utilize the waste material, but to obtain a container similar to the new material that allows the state of food stored inside the container to be easily seen from the outside. be able to. Also, the lid
Bending ribs (6) on the lid (A) and the body (B) adjacent to both sides along the width direction of the joint (C) between the body (A) and the body (B)
Since (6) is formed, the lid (A) is bent rib (6) (6)
The pulling force and bending repulsive force generated during opening and closing via the connector are not directly applied to the connecting part (C), so the overlapping edge part and unbonded part of the connecting part (C) peels off. It does not spoil the appearance of the container. In addition, according to the present invention, the manufacturing process described above has an excellent effect such that the manufacturing time can be shortened and the flow of the production line can be smoothly advanced.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a manufacturing method according to the present invention.

FIG. 2 is an enlarged perspective view showing one step of the manufacturing method.

FIG. 3 is a perspective view showing an example of a container obtained by the manufacturing method of the present invention.

FIG. 4 is a perspective view showing a state in which the container is closed.

FIG. 5 is a front view showing a joining roller portion in the manufacturing method.

FIG. 6 is a partial perspective view showing an example of a connecting portion of the container according to the present invention.

FIG. 7 is a partial perspective view showing another example of the connecting portion.

FIG. 8 is a partial perspective view showing still another example of the connecting portion.

FIG. 9 is a partial large side view showing another example of the container according to the present invention.

10 is an overall perspective view of the container shown in FIG.

[Explanation of symbols]

 (A) Container lid (B) Container body (C) Container joint (K) Single container (D1) (D2) Die (1) Synthetic resin sheet material (2) Synthetic resin sheet material (4) Forming machine (5a) (5b) Flat side edges (6) Bending ribs (9) Cutting machine

Claims (2)

[Claims] 1. A container in which a lid portion (A) having a required uneven three-dimensional shape and a body portion (B) having a required uneven three-dimensional shape are integrally connected by a connecting portion (C), Highly transparent synthetic resin sheet material (1) formed using a new material for the lid part (A)
The body part (B) is made of a low transparency synthetic resin sheet material (2) formed by using waste material, and the connecting part (C) is formed.
Is formed by polymerizing and adhering the adjacent flat side edge portions (5a) and (5b) of the synthetic resin material (1) and (2) forming the lid portion (A) and the body portion (B), Food packaging in which foldable ribs (6), (6) are formed on the lid (A) and the body (B) adjacent to both sides along the width direction of the connecting portion (C). Synthetic resin container. 2. A highly transparent belt-shaped synthetic resin sheet material (1) made of a new material and a highly transparent belt-shaped synthetic resin sheet material (2) made of a waste material are arranged side by side and drawn out. Process and these synthetic resin sheet materials (1), (2)
A flat side edge portion (5a), (5b) along with the side edges adjacent to each other and forming a desired uneven shape on the flat side edge portion (5a), (5b) at the base end portion of the side. Bending ribs along the length direction of the edge portion (6), the step of forming (6), and the flat side edge portions (5a) and (5b) of the synthetic resin sheet materials (1) and (2). A method for producing a synthetic resin container for food packaging, which comprises a step of polymerizing and adhering each other, and a step of cutting the uncut container-forming strip (8) thus continuously molded into a single container (K). .