Packaging container and method of using the same

Abstract

To provide a packaging container having load-bearing properties suitable for load-prone portions such as flange portion and side wall portion, and a method of using the packaging container.SOLUTION: The packaging container has a flange portion outwardly extending continuously from the upper edge of the portion for accommodating the contents. The flange portion has a flange straight portion formed in a straight line and a flange corner portion formed in an arc shape continuing from the flange straight portion, and the width of the flange corner portion is narrower than the width of the flange straight portion in plan view.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a packaging container having a load-bearing capacity suitable for attaching a lid, for example. [Background technology]

[0002] Conventionally, foods such as boxed lunches and side dishes sold in supermarkets and convenience stores have been packaged with a designated container body and a lid material. Most container bodies for packaging food are molded, but lid materials are not limited to molded ones, and include sheet-like materials and plastic wrap. The lid material is selected based on packaging conditions such as the type of food and container body, how the food is eaten, and the storage period.

[0003] A typical container body has various parts including a side wall part that surrounds food placed on the bottom from the sides and a flange part to which a lid material that covers the food from above is attached, and the correlations and causal relationships (hereinafter simply referred to as "relationships") between each part vary. For example, a packaging container equivalent to the container body disclosed in Patent Document 1 has corner parts that bulge outward from the flat part of the side wall parts (see "EE end view"), but the relationship between the above corner parts and each part is not disclosed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Design Registration No. 1635583 Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, by improving the relationship between the above-mentioned parts, it may be possible to provide a packaging container suitable for a lid material selected based on a specified packaging condition. Furthermore, the selection of a lid material suitable for a packaging container is expected to have a direct effect on improving not only the quality of the food to be packaged, but also the value of the entire product. For example, plastic wrap has a cost advantage over molded lid materials, making it suitable for the current era of rising raw material prices.

[0006] However, since the wrap is placed over the packaging container and is stretched by being hooked on the flange, there is a risk that the flange and the side wall may be damaged by the load when the lid is attached. In response to this problem, the inventors have come to the conclusion that a packaging container having a load-bearing capacity suitable for the above-mentioned attachment can be invented by reviewing, for example, the relationship between the flange and the side wall and the relationship between each part including these.

[0007] The flanges and side walls are required to have a certain strength because they are loaded not only when the lid is attached but also when the packaging containers are stacked together. In general, packaging containers made of thermoplastic resins, the strength increases as the sheet basis weight (mass per unit area) increases during molding, but conversely, there is a risk that the cost will increase and moldability will decrease. Therefore, there is a demand to improve the strength of packaging containers, including the flanges and side walls, without increasing the sheet basis weight.

[0008] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide a packaging container having a load-bearing capacity suitable for portions that are easily subjected to load, such as flanges and side walls, and a method for using the packaging container. [Means for solving the problem]

[0009] In other words, the packaging container of the present invention has a flange portion extending outwardly continuously from the upper edge of the content storage section, and the flange portion has a flange linear portion formed in a straight line and a flange corner portion formed in an arc shape continuous with the flange linear portion, and is characterized in that the width of the flange corner portion in a plan view is narrower than the width of the flange linear portion.

[0010] It is also preferable that the end of the straight portion of the flange be formed into an arc shape so as to be continuous with the flange corner portion.

[0011] Moreover, it is preferable that the flange linear portion is formed in a stepped shape in the height direction.

[0012] In addition, it is desirable that the storage section has a bottom and a side wall section rising upward from the peripheral edge of the bottom, the side wall section having a side wall planar section formed in a flat shape and a side wall corner section formed in an arc shape continuous with the side wall planar section, and the side wall corner section protruding outward from the side wall planar section.

[0013] Moreover, it is preferable that the side wall corner portion protrudes outwardly to a position 10 to 15 mm downward from the flange corner portion.

[0014] The method of using the packaging container of the present invention is characterized in that the opening of the packaging container is wrapped with plastic wrap. Effect of the Invention

[0015] According to the present invention, it is expected to have an effect of providing load resistance suitable for parts that are easily subjected to load, such as flanges and side walls. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a perspective view of a packaging container according to one embodiment of the present invention. [Figure 2A] FIG. 2 is a plan view of the packaging container. [Figure 2B] FIG. [Figure 2C] FIG. 2 is a reference diagram for clarifying a cross-sectional portion or an end surface portion using the above plan view. [Diagram 3] FIG. 2 is an enlarged cross-sectional view of the CC portion of the above reference diagram. [Figure 4] FIG. 2 is a front view of the packaging container. [Diagram 5]2 is an end view of the AA and DD portions of the reference diagram and the EE portion of the front diagram. FIG. [Figure 6] FIG. 2 is a bottom view of the packaging container. [Figure 7] FIG. 2 is a rear view of the packaging container. [Figure 8] FIG. 2 is a left side view of the packaging container. [Figure 9] FIG. 2 is an enlarged cross-sectional view of the AA portion in the DD portion of the above reference figure. [Figure 10] FIG. 1 is an enlarged cross-sectional view of the BB portion in the CC portion of the reference diagram. [Figure 11] FIG. 2 is a shaded top perspective view of a packaging container according to another embodiment of the present invention. [Figure 12] FIG. 2 is a shaded bottom perspective view of the packaging container. [Figure 13] FIG. 2 is an enlarged plan view of a packaging container according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, a packaging container according to one embodiment of the present invention (hereinafter also referred to as "this packaging container") will be described with reference to Figs. 1 to 5. In these figures, some parts where there are a plurality of identical parts are numbered only for one part. In the description, terms indicating directions such as upward, downward, lateral, vertical, horizontal, inward, outward, central, and circumferential directions are basically based on the packaging container installed in the normal orientation, and will be explained appropriately when other directions are used as the reference. A plan view means that the packaging container is viewed from directly above. A cross-sectional view or end view means that a cut part is viewed from the front. A right side view of this packaging container is omitted because it appears the same as the left side view. Figures 6 to 12 are based on Figs. 1 to 5, so numbering is omitted.

[0018] <Basic composition of this packaging container> This packaging container is used to package foods such as prepared foods, bento lunches, sushi, sashimi, and salads to be sold in supermarkets and other retail stores, and comprises a container body T that contains the food, and a lid material (not shown) (hereinafter simply referred to as "lid material") that is attached to the container body T. This packaging container is square in plan view, but it may be triangular, rectangular, or polygonal with pentagons or more, and there are no limitations on dimensions such as length, width, and height as long as it is large enough to be placed on a display shelf in a retail store.

[0019] <Overview of container body T> 1, the container body T includes a storage section T1 composed of a bottom 1 on which food is placed, a side wall section 2 that rises upward continuously from the peripheral edge of the bottom section 1, and a flange section 3 that extends outward continuously from the upper edge of the side wall section 2 that corresponds to the upper edge of the storage section T1. The container body T is square in plan view, but may be triangular or rectangular, or may be a polygonal shape with pentagons or more sides as long as a lid can be attached.

[0020] When the container body T has a rectangular shape in plan view, the lengths of the longitudinal and lateral directions of the container body T may be 80 to 450 mm, and more preferably 100 to 300 mm. Regardless of whether the container body T has a rectangular shape in plan view or not, the height from the lowermost end of the bottom portion 1 to the uppermost end of the flange portion 3, which corresponds to the height of the container body T, may be 10 to 100 mm, and more preferably 30 to 70 mm.

[0021] <Details of flange part 3> 1, 2A, and 2B, the flange portion 3 has a flange straight portion 31 formed in a straight line and a flange corner portion 32 formed in an arc shape continuous with the flange straight portion 31, and the width W1 of the flange corner portion 32 is narrower than the width W2 of the flange straight portion 31 in a plan view. With this configuration, a step is formed between the flange straight portion 31 and the flange corner portion 32 in a plan view, so that the strength of the flange corner portion 32 and the side wall corner portion 22 formed downwardly continuous with the flange corner portion 32 against a load from above can be improved, and the silhouette can be prevented from being distorted by recessing the inside to the outside. The height of the flange portion 3 is the same all around the circumference, but may be partially different by, for example, having a recess (not shown) recessed downward around the center of the flange straight portion 31.

[0022] 2B is 4 to 20 mm, preferably 6 to 15 mm, and more preferably 8 to 12 mm, and if it is narrower than 4 mm it is difficult to attach a lid, and if it is wider than 20 mm it may break or bend. The ratio of the width W1 of the flange corner portion 32 to the width W2 of the flange straight portion 31 is 1:1 to 1:3, and if W1 is smaller than 1:1 it is difficult to increase the strength of the side wall corner portion 22, and if W2 is larger than 1:3 it may result in a distorted outer shape and reduce the strength of the side wall corner portion 22.

[0023] As shown in Fig. 1 and Fig. 2A, the width W1 of the flange corner portion 32 may vary depending on the cutting process of the molding method of the container body T, in which an acrylic plate or the like is placed on the molded flange portion 3 and cut it. The cutting process may be, for example, a method in which the plate is placed on the lower side (rear side) of the flange portion 3 and a cutting blade is moved from top to bottom from the upper side (front side) to cut it, or a method in which the plate is placed on the upper side (front side) of the flange portion 3 and a cutting blade is moved from bottom to top from the lower side (rear side) to cut it (so-called "edge cutting method"). The edge cutting method has the effect of narrowing the width W1 of the flange corner portion 32 to easily increase the sharpness, and in this case, the width W1 may be 4 to 12.5 mm.

[0024] <Details of the flange straight portion 31> 2A and 2B, the flange straight portion 31 has a flange straight inner edge portion 31a corresponding to the upper edge of the side wall portion 2, and the end of the flange straight inner edge portion 31a is formed in an arc shape curved toward the inside of the container body and is continuous with the flange corner portion 32, in other words, the flange straight inner edge portion 31a has a flange straight inner edge end portion 31ax adjacent to the flange corner portion 32. With this configuration, it can be expected that stress will be less likely to concentrate on the flange corner portion 32, compared to when the end of the flange straight inner edge portion 31a is formed in a straight line.

[0025] The radius of curvature of the linear inner flange edge 31ax shown in Fig. 2B is 5 to 500 mm, preferably 10 to 300 mm, and more preferably 30 to 100 mm. If it is less than 5 mm, the difference between the width W1 and the width W2 becomes too small, and molding becomes difficult. If it is more than 500 mm, the radius of curvature of the flange corner portion 32 may become too large and the flange strength may be weakened.

[0026] 2B and 3, the flange straight portion 31 is stepped in the height direction, specifically, the flange straight step portion 31b is formed stepwise from the flange straight inner edge portion 31a outward and upward. This configuration not only improves the strength of the flange straight portion 31, but also makes the width appear narrower. The flange straight portion 31 has a flange straight outer edge 31c that corresponds to the outermost end of the container body T, and has a generally arc-shaped portion in end view between the upper edge of the flange straight step portion 31b and the flange straight outer edge 31c.

[0027] The flange straight line portion 31 may be not only straight, but also arcuately curved toward the outside of the container body T. The flange straight line portion 31 may be formed continuously from the flange straight line inner edge portion 31a to the flange straight line outer edge portion 31c without the flange straight line step portion 31b, the flange straight line inner edge portion 31a and the flange straight line outer edge portion 31c may be at the same height or at different heights, and may have a flat portion or a semi-cylindrical portion in end view between the flange straight line inner edge portion 31a and the flange straight line outer edge portion 31c.

[0028] <Details of flange corner part 32> As shown in FIG. 2B, the radius of curvature of the flange corner inner edge 32a, which is continuous with the flange linear inner edge 31a, and the radius of curvature of the flange corner outer edge 32b, which is continuous with the flange linear outer edge 31c, are 3 to 30 mm, preferably 4 to 20 mm, and more preferably 5 to 15 mm. If it is less than 3 mm, it is difficult to mold, and if it is more than 30 mm, the strength of the side wall corner 22 may be reduced, and the effect of this function may be reduced. The ratio of the radius of curvature of the flange corner inner edge 32a to the radius of curvature of the flange corner outer edge 32b is 1:1 to 1:10. If the flange corner inner edge 32a is larger than 1:1, the container body T becomes too thin, and the flange becomes wide and easily bent. If the flange corner outer edge 32b is larger than 1:10, the container body T may become too thick and it may be difficult to form the shape.

[0029] <Details of side wall portion 2> 1, 2C, 4, and 5, the sidewall portion 2 has a sidewall planar portion 21 formed in a flat shape, and a sidewall corner portion 22 formed in an arc shape continuous with the sidewall planar portion 21, and the sidewall corner portion 22 protrudes outward from the sidewall planar portion 21. According to this configuration, a step is generated between the sidewall planar portion 21 and the sidewall corner portion 22, so that the strength of the sidewall corner portion 22 can be expected to be improved.

[0030] <Details of the side wall flat portion 21> The sidewall flat portion 21 shown in FIG. 5 is continuous with the sidewall corner portion 21 through a gentle curve, in other words, has a sidewall flat curved end portion 21a adjacent to the sidewall corner portion 22. The upper edge of the sidewall flat curved end portion 21a corresponds to the flange linear inner end portion 31ax, in other words, the flange linear inner end portion 31ax is formed by the formation of the sidewall flat curved end portion 21a. The center of the sidewall flat portion 21 may be curved toward the inside or outside of the container body T, and may be formed in one or more steps in the height direction and / or circumferential direction of the container body T. The angle of the sidewall flat portion 21 with respect to the horizontal plane is not particularly limited, and is preferably 20° to 80°, more preferably 30° to 60°.

[0031] <Relationship between side wall flat portion 21 and flange linear inner edge portion 31ax> As shown in FIG. 2B, the fact that width W1 of flange corner portion 32 is narrower than width W2 of flange straight portion 31 is related to the fact that sidewall corner portion 22 protrudes outward from sidewall flat portion 21 as shown in FIG. 5. As described above, narrowing width W1 of flange corner portion 32 causes sidewall corner portion 22 to protrude outward, thereby obtaining the desired effect. In other words, even if sidewall corner portion 22 protrudes outward, the desired effect cannot be obtained unless width W1 of flange corner portion 32 is narrowed.

[0032] <Details of the side wall corner portion 22> 3 and 4, the sidewall corner portion 22 may protrude outward from the flange corner portion 32 to a height position P that is 10 to 15 mm downward. With this configuration, the sidewall corner portion 22 does not protrude outward below the height position P, in other words, the sidewall corner portion 22 is continuous with the sidewall flat portion 21 below the height position P without a step at the boundary with the sidewall flat portion 21, which is expected to have the effect of making the sidewall corner portion 22 easier to mold. The height position P may be calculated from the upper edge of the sidewall corner portion 22 that corresponds to the flange corner inner edge portion 32a.

[0033] As shown in FIG. 5, the protrusion amount W3 of the sidewall corner portion 22 relative to the sidewall flat portion 21 is 1 to 15 mm, preferably 1.5 to 10 mm, and more preferably 2 to 6 mm, as the distance between the outer surface of the sidewall flat portion 21 as a reference and an imaginary line that is drawn parallel to the outward direction and contacts the sidewall corner portion 22. If it is less than 1 mm, the sidewall corner portion 22 will not be strong enough, and if it is more than 15 mm, the outer shape will be distorted, which may result in insufficient capacity of the storage portion T1.

[0034] 5 has a radius of curvature of 1 to 15 mm, preferably 2 to 10 mm, and more preferably 4 to 8 mm, and if it is less than 1 mm, molding is difficult, and if it is more than 15 mm, the strength of sidewall corner portion 22 may be reduced. The angle of sidewall corner portion 22 with respect to the horizontal plane may be the same as or different from the angle of sidewall planar portion 21.

[0035] <Details of bottom 1> 1 and 2A, the bottom 1 has an unnumbered raised portion over substantially the entire central portion, which determines the orientation, angle, arrangement, etc. of the contents to be placed thereon, but it may have such a raised portion over a portion of the central portion or outside the central portion, may be flat without the raised portion, or may have groove-like legs (not shown) formed outward from the peripheral edge. The area of ​​the bottom 1 is narrower than the area of ​​the opening of the container body T in a plan view due to the flange portion 3, but it may be wider or substantially equal.

[0036] <Specifications of container body T, including material, forming method, dimensions, etc.> The container body T is molded using a synthetic resin sheet as a base material. The synthetic resin sheet may be made of, for example, an olefin resin such as polyethylene (PE) or polypropylene (PP), polystyrene paper (PSP) made of a polystyrene resin, high impact polystyrene (HIPS) in which an elastic material such as a butadiene copolymer is blended with GP polystyrene to improve impact resistance, or a polyester resin such as polyethylene terephthalate (PET), and may be composed of a single layer or multiple layers, may be colored or colorless transparent, or may be opaque, and may be formed of a material having heat resistance. The synthetic resin sheet is formed into a desired shape of the container body by a thermoforming method such as vacuum molding, hot plate pressure molding, vacuum pressure molding, double-sided vacuum molding, etc. The front and / or back of the synthetic resin sheet may be laminated with a synthetic resin film. The synthetic resin film may be composed of a single layer or multiple layers having heat resistance, oil resistance, lamination suitability with a printed layer, gas barrier property, etc., and may include a printed layer when the surface of the synthetic resin sheet is laminated.

[0037] The synthetic resin sheet may be made of foamed resin or non-foamed resin. There is no particular limit to the thickness of the synthetic resin sheet, but in the case of non-foamed resin, the thickness is 0.15 to 1 mm, preferably 0.16 to 0.8 mm, and more preferably 0.18 to 0.6 mm. In the case of low-foamed resin with an expansion ratio of 1.5 to 3 times, the thickness is 0.5 to 3 mm, and preferably 1 to 2 mm. In the case of high-foamed resin with an expansion ratio of 5 to 15 times, the thickness is 1.5 to 5 mm, preferably 1.8 to 4 mm, and more preferably 2.0 to 3.5 mm. The expansion ratio is calculated by measuring the specific volume (unit: cc / g) of the foamed composition before expansion and the foamed sheet after expansion, and calculating the specific volume after expansion / specific volume before expansion.

[0038] For foamed resin, the basis weight (mass per unit area) is 120 to 220 g / m 2 However, as the material becomes heavier, the amount of resin increases, which is preferable because it is relatively easier to obtain the desired strength, but the material cost increases accordingly, so it is necessary to select a material weight that takes into account this balance. The preferred weight is 130 to 220 g / m 2, and more preferably 140 to 200 g / m 2 , more preferably 150 to 200 g / m 2 It is.

[0039] <Specifications for lid material, forming method, dimensions, etc.> As a lid material, plastic wrap is suitable, but sheet-like or molded products may also be used. For example, plastic wrap is mainly made of polyvinyl chloride, polyethylene, vinyl chloride, polyvinylidene chloride, and polyolefin. Plastic wrap is around 15 microns thick and has a width ranging from about 300 mm in 50 mm increments, and is used according to the size of the container body. Supermarkets and packing centers (food factories) use hand wrap or automatic packaging machines for wrapping.

[0040] <How to use with a wrap> For example, when the container body T shown in Fig. 1 is put into a push-up packaging machine, the wrap covers the opening of the container body T and gets caught on the flange portion 3, generating a load that rolls the side wall portion 2 downward. At this time, the flange corner portion 32 and the side wall corner portion 22 are most heavily loaded, but because the above-mentioned configuration has improved strength, it is possible to prevent bending that occurred in conventional container bodies.

[0041] The packaging container shown in this embodiment is not limited to the above-mentioned contents, and includes the positions, shapes, and dimensions of all parts, the relationships between the parts, and the methods of use as long as the same effects can be obtained.

[0042] With reference to Fig. 13, a packaging container according to another embodiment of the present invention will be described in terms of differences from the packaging container described above, and a description of equivalent parts will be omitted. For ease of reference, parts or portions corresponding to those shown in Fig. 2B are numbered in Fig. 13 with 100 added to the numbers in Fig. 2B.

[0043] The flange straight-line inner edge end portion 131ax connecting the flange straight-line inner edge portion 31a and the flange corner inner edge portion 32a may be a single straight line as shown in Figure 13(A), or may be a straight line inclined outwardly on the flange straight-line inner edge portion 31a side and straight line parallel to the flange straight-line inner edge portion 31a on the flange corner inner edge portion 32a side as shown in Figure 13(B), or may be a curved line bulging outwardly on the flange straight-line inner edge portion 31a side and straight line parallel to the flange straight-line inner edge portion 31a on the flange corner inner edge portion 32a side as shown in Figure 13(C). [Explanation of symbols]

[0044] T Container Body 1 bottom 2 Side wall 21 Side wall planar part 21a Side wall planar curved end 22 Side wall corner 3 Flange 31 Flange straight section 31a Flange straight inner edge 31ax Flange straight inner edge (other, 131ax) 31b Flange linear step portion 31c Flange straight outer edge 32 Flange corner part 32a Flange corner inner edge 32b Flange corner outer edge

Claims

1. A flange portion is provided extending outwardly from an upper end edge of the content storage portion, The flange part is A flange linear portion formed in a linear shape; The flange has a straight flange portion and a flange corner portion formed continuously in an arc shape, In plan view, the width of the flange corner portion is narrower than the width of the flange straight portion A packaging container characterized by:

2. The end of the straight flange section is formed into an arc shape and continues with the flange corner section.

2. The packaging container according to claim 1.

3. The straight flange portion is formed in a stepped shape in the height direction.

3. The packaging container according to claim 1 or 2.

4. The storage section includes a bottom and a side wall section rising upward from a peripheral edge of the bottom. The side wall portion has a side wall planar portion formed in a flat plane and a side wall corner portion formed in an arc shape continuous with the side wall planar portion, The side wall corner portion protrudes outward from the side wall flat portion.

2. The packaging container according to claim 1.

5. The side wall corner portion protrudes outward from the flange corner portion to a position 10 to 15 mm below.

5. The packaging container according to claim 4.

6. The opening of the packaging container according to claim 1 or 2 is wrapped with a plastic wrap. A method for using a packaging container comprising the steps of:

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