JP7352342B2 - container - Google Patents

Description

The present invention relates to containers.

When the moist contents of a container are cooked in a microwave, steam is generated and the internal pressure causes the container to burst. To avoid this, there is a known technique for automatic steam ventilation, in which when a certain internal pressure is applied, a hole is automatically opened to communicate the inside and outside of the container, and the steam is discharged. As one of the mechanisms of this automatic steaming, the joint strength between the container body and the lid in the steaming section is made lower than the joint strength other than the steaming section (so that the joint strength is low). Some devices use sealing to selectively destroy the joints of the ventilation portions when the internal pressure rises to create ventilation holes. A technique using such a vapor passage section is described in, for example, Patent Document 1.

JP2017-085983A

However, once the strength reaches a certain value, the bonding strength between resin materials remains almost constant even if the sealing conditions are changed; however, in the region where the strength is low, the bonding strength changes depending on the sealing conditions, such as the sealing temperature in the case of heat sealing. sensitive to Therefore, when attempting to form a vapor passage part with low bonding strength as described above, the bonding strength changes greatly due to errors in sealing conditions caused by manufacturing equipment and environmental factors during manufacturing, making vapor passage unstable. There is a possibility that it will become.

Therefore, as in the example shown in FIG. 7, a technique has also been proposed in which the vapor passage portion 941 is formed by a knurled seal formed using a seal disk in which square pyramid-shaped convex portions are arranged. In this case, the bonding strength is lower in the region 941B corresponding to the slope of the protrusion than in the region 941A corresponding to the apex of the protrusion formed on the seal disc, thereby stably achieving low bonding strength. I can do it.

However, in the above-described vapor passage portion 941, there is a possibility that unsealed portions may occur due to the bonding strength further decreasing in the region 941C corresponding to the valley portion between the convex portions formed on the seal disk. If the unsealed portion of the region 941C continues from the inside of the container to the outside, seal leakage will occur and the sealing performance of the container will be impaired.

In view of the above, an object of the present invention is to provide a container that can stably form a vapor passage portion with a desired sealing strength and maintain the sealing performance of the container.

According to one aspect of the present invention, the first container body includes a first container body, and the second container body is joined to the first container body at a joining area located at the periphery of an internal space formed by the first container body, and A container is provided in which a plurality of mutually isolated non-bonded regions are formed in a portion of the region in the circumferential direction.
According to the above configuration, a part of the circumferential direction of the joint area is made into a ventilation part, and by forming a plurality of non-joint areas in this part, it is possible to stably form a ventilation part with a desired sealing strength. I can do it. Furthermore, since the non-bonded regions are isolated from each other, seal leakage can be prevented and the sealing performance of the container can be maintained.

In the above container, the area of each non-bonded region may be 0.1 mm ² or more. Further, the first container body includes a cup-shaped recess forming an internal space and a flange formed at the peripheral edge of the recess, and the second container main body is connected to the first container at a joining area located in the flange. It may also be a film-like lid that is joined to the main body.

In the above container, the first container body is made of a laminate including at least a first layer and a second layer, and includes a recess and a flange formed at a peripheral edge of the recess, and the joining region is formed in the flange, The bonding strength between the second container body and the second layer is stronger than the interlayer bonding strength between the second layer and the first layer, and the missing portion of the second layer is formed closer to the recess than the bonding area. It's okay.

In the above container, the first container body includes a recess and a flange formed at a peripheral edge of the recess, the joint region is formed in the flange, and the first container body includes a first layer and a flange formed at a peripheral edge of the recess. The second container body is composed of a laminate including at least a second layer that is bonded and faces the bonding area, and the second container body is a laminate that includes at least a third layer that faces the bonding area and a fourth layer that is bonded to the third layer. Either the second layer or the third layer is a cohesive failure layer, and the cohesive strength of the cohesive failure layer is the bonding strength between the lid body and the container body, the first to fourth layers. It may be weaker than the cohesive strength of each layer other than the cohesive failure layer and the interlayer bonding strength between the first layer and the second layer and between the third layer and the fourth layer. In this case, at the edge of the joint region on the concave side, there is a first resin reservoir part made of the resin forming the first layer and the second layer and having a knob-shaped cross section tilted toward the concave side, and a third layer of the resin. A second resin reservoir may be formed of resin and have a knob-shaped cross section and be located closer to the recess than the first resin reservoir.

According to the present invention, it is possible to stably form a vapor passage portion with a desired sealing strength and maintain the sealing performance of the container.

FIG. 1 is a perspective view of a container according to an embodiment of the present invention. FIG. 2 is an enlarged view showing the steam passage section of the container shown in FIG. 1. FIG. FIG. 7 is an enlarged view showing a vapor passage portion of a container according to a modified example. FIG. 3 is a partial cross-sectional view of a container according to a second embodiment of the present invention. FIG. 7 is a partial cross-sectional view of a container according to a third embodiment of the present invention. It is a graph showing the relationship between puncture pressure strength and seal temperature in Examples and Comparative Examples. FIG. 3 is a diagram showing an example of a knurled seal according to the prior art.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Note that, in this specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals and redundant explanation will be omitted.

FIG. 1 is a perspective view of a container according to a first embodiment of the invention. As shown in FIG. 1, the container 100 includes a container body 110 and a lid 130. The container body 110 has, for example, a substantially circular planar shape as shown, and includes a cup-shaped recess 111 and a flange 112 formed at the periphery of the recess 111. The lid body 130 is a film-like member that covers the opening of the recess 111, and is bonded to the container body 110 using heat sealing, ultrasonic sealing, or the like at an annular bonding area 140 formed in the flange portion 112. An internal space SP is formed between the concave portion 111 and the concave portion 111 . That is, the joining region 140 is located at the periphery of the internal space formed by the container body 110. A vapor passage portion 141 as described later is formed in a portion of the bonding region 140 in the circumferential direction. In this embodiment, the container body 110 and the lid 130 are formed of various resin materials that can be used as containers, or a laminate of resin materials. Additives such as inorganic materials may be added to the resin material as necessary.

FIG. 2 is an enlarged view of the steam passage section of the container shown in FIG. 1. As shown in the figure, in the vapor passage section 141, approximately circular non-bonded regions 141A each having a diameter φ are arranged in the bonding region 140 at a center spacing d. Here, an array means that it is formed in a regular positional relationship. The respective non-bonded regions 141A are isolated without contacting each other (that is, d>φ). The non-bonded region 141A is formed, for example, by forming a concave portion of the same shape in the seal disc and not applying heat or ultrasonic waves to the concave portion. By forming the non-bonded region 141A, the bonding strength in the vapor passage section 141 is made lower than that in other parts, or the rate of change of the bond strength with respect to the sealing temperature (or the intensity of ultrasonic waves) is made gentler in the vapor passage section 141. It can be done.

FIG. 3 is an enlarged view of a vapor passage portion of a container according to a modified example. As illustrated, in the vapor passage section 141 of the container according to the modified example, non-bonded regions 141B having a rounded V-shape are arranged. Also in this modification, the non-bonded regions 141B are isolated without contacting each other. The non-bonded region 141B is also formed, for example, by forming a concave portion of the same shape in the seal disk and not applying heat or ultrasonic waves to the concave portion. When forming the non-bonded region 141B, the bonding strength is made lower in the vapor passage part 141 than in other parts, or the rate of change of the bond strength with respect to the sealing temperature (or the intensity of ultrasonic waves) is made gentler in the vapor passage part 141. It can be done.

As shown in the example of FIG. 3 above, in this embodiment, it is possible to arrange the non-bonding regions in various shapes, not just a substantially circular shape, in the vapor passage section 141. In addition to the shape shown in the example of FIG. 3, the non-bonded regions may be arranged in a polygonal shape, an elliptical shape, or the like. Further, the shapes of the non-bonded regions may not all be the same; for example, the vapor passage portion 141 may be formed by arranging non-bonded regions having a plurality of types of shapes. In either case, since the non-bonded regions are isolated without contacting each other, the occurrence of seal leakage that communicates the inside and outside of the container 100 is prevented.

(Second embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. 4. Note that, except for the points described below, the configuration of this embodiment is the same as the configuration of the above-described first embodiment including the steaming section 141, so a duplicate explanation will be omitted.

FIG. 4 is a partial cross-sectional view of a container according to a second embodiment of the invention. In this embodiment, as shown in FIG. 4, the container body 110 is formed by forming a laminate 114 including a base layer 114A and a surface layer 114B into a shape including a recess 111 and a flange 112 by vacuum forming or pressure forming. It is molded. The base layer 114A is located on the outside of the container body 110 and exhibits the rigidity required to maintain the shape of the container body 110. The surface layer 114B is located inside the container body 110, that is, on the side facing the internal space SP. In the bonding region 140, the lid 130 is bonded to the surface layer 114B of the laminate 114. As will be described later, the bonding strength between the lid 130 and the surface layer 114B in the bonding region 140 is stronger than the interlayer bonding strength between the base layer 114A and the surface layer 114B in the laminate 114.

Here, the base material layer 114A of the laminate 114 is formed of, for example, a resin containing at least one of the group consisting of an olefin resin, a polystyrene resin, and a polyester resin. Examples of the olefin resin include polypropylene and polyethylene. An example of the polyester resin is polyethylene terephthalate (PET). An inorganic filler such as talc may be added to the base layer 114A to improve rigidity.

On the other hand, the surface layer 114B of the laminate 114 is made of, for example, a polyolefin resin. Examples of polyolefin resins include polypropylene resins such as homopolypropylene (HPP), random polypropylene (RPP), and block polypropylene; polyethylene resins such as high density polyethylene (HDPE) and low density polyethylene (LDPE); Examples include linear ethylene-α-olefin copolymers.

Note that in the illustrated example, the laminate 114 includes two layers, a base layer 114A and a surface layer 114B, but in other examples, the laminate 114 may include additional layers. For example, when high rigidity is required, the laminate 114 may include a plurality of base material layers and an adhesive layer that adheres the base material layers to each other. The adhesive layer is formed of, for example, a urethane-based elastomer, a styrene-based elastomer, maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, ethylene vinyl acetate (EVA), or the like. Further, the stacked body 114 may include a gas barrier layer that blocks oxygen and the like. The gas barrier layer is formed of, for example, saponified ethylene-vinyl acetate copolymer (EVOH), polyvinylidene chloride (PVDC), or polyacrylonitrile (PAN).

Furthermore, in this embodiment, a cut 115 is formed in the flange portion 112 of the container body 110 along the joining region 140. The cut 115 is formed in at least the surface layer 114B of the laminate 114 at the flange portion 112 closer to the recess 111 than the bonding region 140. As will be described later, the notch 115 is an example of a missing portion of the surface layer 114B. In the illustrated example, the cut 115 just penetrates only the surface layer 114B and does not reach the base layer 114A, but the cut 115 may reach a part of the base layer 114A. Alternatively, the cuts 115 may not penetrate the surface layer 114B, but may remain thick enough that the surface layer 114B can be easily broken when the container is opened. Note that although the cross-sectional shape of the cut 115 is V-shaped in the illustrated example, it may be other shapes such as U-shape or I-shape.

The lid body 130 consists of a film-like laminate 131 including an outer layer 131A and a sealing layer 131B. The outer layer 131A is located on the front side of the lid 130, that is, on the side not facing the container body 110, and exhibits the flexibility and tensile strength required for the lid 130. The sealing layer 131B is located on the back side of the lid 130, that is, on the side facing the container body 110, and is bonded to the surface layer 114B of the laminate 114 forming the container body 110 in the bonding region 140. Here, the outer layer 131A of the laminate 131 is formed of, for example, a polyethylene terephthalate (PET) film or a biaxially stretched nylon film (O-Ny). Further, the seal layer 131B of the laminate 131 is formed of a resin composition such as random polypropylene (RPP), block polypropylene (BPP), linear low density polyethylene (LLDPE), or polyethylene.

In addition, in other examples, the laminate 131 constituting the lid body 130 does not necessarily have to be in the form of a film, but may be a sheet-like laminate formed into a predetermined shape similarly to the laminate 114 constituting the container body 110. It may be. In this case, the container can be said to include a first container body and a second container body that are compatible. The laminate that constitutes the first container body includes a first layer and a second layer, and by forming a missing part in the second layer, the container can be assembled by utilizing delamination between the first layer and the second layer. Can be opened. In the above example, the first container body is the container body 110 and the second container body is the lid 130, but the lid 130 is configured by using the first container body as the lid 130 and the second container body as the container body 110. It is also possible to form a cutout in the second layer of the laminate. Similar configurations are also possible in other embodiments described below.

Next, the operation of opening the container shown in FIG. 4 will be explained. As shown in FIGS. 4(A) and 4(B), the user can begin opening the container by grasping the extended end of the lid 130 and peeling off the lid 130 from there. can.

Here, as described above, the bonding strength between the lid 130 and the surface layer 114B in the bonding region 140 is stronger than the interlayer bonding strength between the base layer 114A and the surface layer 114B of the laminate 114. Therefore, when the user peels off the lid 130 as described above, the surface layer 114B bonded to the lid 130 in the bonding region 140 near the end of the laminate 114 is peeled off together with the lid 130, while the There is delamination between the base layer 114A and the surface layer 114B of the body 114.

When the user further peels off the lid 130, the surface layer 114B separates from the lid 130 at the cut 115, and from there on, only the lid 130 is peeled off. This is because, as described above, the cut 115 is formed to penetrate the surface layer 114B, or the cut 115 has a thickness such that the surface layer 114B can be easily broken.

The container according to this embodiment is opened according to the procedure described above. If the interlayer bonding strength between the base layer 114A and the surface layer 114B of the laminate 114 is weakened, the force required by the user to peel off the lid 130 when opening the package will be small, making the package easier to open. On the other hand, before opening, when the container body 110 and the lid body 130 are joined to each other, the internal pressure of the internal space SP is applied to the joining region 140, more specifically, to the edge of the joining region 140 on the recess 111 side. concentrate. Since the cut 115 is spaced apart from the edge of the bonding region 140, concentrated internal pressure is prevented from acting to cause delamination of the laminate 114 starting from the cut 115. Therefore, even if opening is made easier by weakening the interlayer bonding strength as described above, it is possible to resist high internal pressure by increasing the bonding strength between the lid 130 and the surface layer 114B. can. In this way, the container according to this embodiment can achieve both ease of opening and resistance to internal pressure. In order to maintain sealing performance, the thickness of the surface layer for delamination (surface layer 114B in the above example) is preferably 10 μm to 200 μm, more preferably 50 μm to 150 μm.

(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG. Note that, except for the points described below, the configuration of this embodiment is the same as the configuration of the above-described first embodiment including the steaming section 141, so a duplicate explanation will be omitted. Note that in the description of the second embodiment and this embodiment above, the constituent elements are independently numbered, so the numbers do not correspond between the second embodiment and the third embodiment. The components that are used do not necessarily match.

FIG. 5 is a partial cross-sectional view of a container according to a third embodiment of the present invention. In this embodiment, as shown in FIG. 5, the container body 110 is constructed by forming a laminate 114 including a base layer 114A, a lower surface layer 114B, and a surface layer 114C into a recess 111 and a flange 112 by vacuum forming or pressure forming. It is molded into a shape that includes. The base layer 114A is located on the outside of the container body 110 and exhibits the rigidity required to maintain the shape of the container body 110. The lower surface layer 114B is located between the base layer 114A and the surface layer 114C, and is bonded to each layer. The surface layer 114C is located inside the container body 110, that is, on the side facing the internal space SP, and faces the joining region 140 formed in the flange portion 112.

Here, the base material layer 114A and the lower surface layer 114B of the laminate 114 are formed of, for example, a resin containing at least one of the group consisting of an olefin resin, a polystyrene resin, and a polyester resin. Examples of the olefin resin include polypropylene and polyethylene. An example of the polyester resin is polyethylene terephthalate (PET). For example, the rigidity is different between the base layer 114A and the lower surface layer 114B. An inorganic filler such as talc may be added to the base layer 114A to improve rigidity.

On the other hand, the surface layer 114C of the laminate 114 is formed of a resin composition obtained by blending at least one of an ethylene-acrylic acid ester-maleic anhydride copolymer or a styrene-grafted propylene resin with a polypropylene resin, for example. be done. In this case, the ethylene-acrylic acid ester-maleic anhydride copolymer or styrene-grafted propylene resin is preferably 10 to 50 parts by weight, particularly preferably 15 to 40 parts by weight, based on 100 parts by weight of the polypropylene resin. It is sufficient to add about 1 part by mass.

Note that in the illustrated example, the laminate 114 includes three layers: a base layer 114A, a lower surface layer 114B, and a surface layer 114C, but in other examples, the laminate 114 may include additional layers. For example, when high rigidity is required, the laminate 114 may include a plurality of base material layers and an adhesive layer that adheres the base material layers to each other. The adhesive layer is formed of, for example, a urethane-based elastomer, a styrene-based elastomer, maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, ethylene vinyl acetate (EVA), or the like. Further, the stacked body 114 may include a gas barrier layer that blocks oxygen and the like. The gas barrier layer is formed of, for example, saponified ethylene-vinyl acetate copolymer (EVOH), polyvinylidene chloride (PVDC), or polyacrylonitrile (PAN).

The lid body 130 consists of a film-like laminate 131 including an outer layer 131A and a sealing layer 131B. The outer layer 131A is located on the front side of the lid 130, that is, on the side not facing the container body 110, and exhibits the flexibility and tensile strength required for the lid 130. The outer layer 131A is formed of, for example, a polyethylene terephthalate (PET) film or a biaxially stretched nylon film (O-Ny). On the other hand, the sealing layer 131B is located on the back side of the lid 130, that is, on the side facing the container body 110, and faces the joining region 140 formed in the flange portion 112. The seal layer 131B is formed of a resin composition such as random polypropylene (RPP), block polypropylene (BPP), linear low density polyethylene (LLDPE), or polyethylene. In this embodiment, the outer layer 131A and the seal layer 131B are joined to each other. Note that in other embodiments, the laminate 131 may also include additional layers.

Here, in this embodiment, the cohesive strength of the surface layer 114C of the laminate 114 is weaker than the bonding strength between the lid 130 and the container body 110 in the bonding region 140, and the laminate 114 and the laminate 131 are It is weaker than the cohesive strength of each layer other than the surface layer 114C, and is also weaker than the interlayer bonding strength between the layers of the laminate 114 and the laminate 131. In other words, when the lower surface layer 114B is the first layer, the surface layer 114C is the second layer, the seal layer 131B is the third layer, and the outer layer 131A is the fourth layer, the cohesive strength of the second layer is the same as that of the lid 130 and the container. The bonding strength with the main body 110, the cohesive strength of the first layer, the third layer, and the fourth layer, and the interlayer bonding strength between the first layer and the second layer and between the third layer and the fourth layer. weaker than Accordingly, as will be described later, in this embodiment, the surface layer 114C is a cohesive failure layer, so that the container can be easily opened. In addition, in this specification, the cohesive strength means the strength exerted by the intermolecular force (cohesive force) that binds the resins forming each layer of the laminate.

Furthermore, in this embodiment, as shown in FIG. 5, a first resin reservoir 121 and a second resin reservoir 122 are formed at the edge of the bonding region 140 on the recess 111 side. The first resin reservoir 121 is made of resin that forms the lower surface layer 114B and the surface layer 114C of the laminate 114, and has a knob-shaped cross section inclined toward the recess 111. The second resin reservoir 122 is made of resin that forms the seal layer 131B of the lid 130, and has a knob-shaped cross section located closer to the recess 111 than the first resin reservoir 121. As illustrated, the surface layer 114C is formed along the surface of the first resin reservoir 121 and through the gap between the first resin reservoir 121 and the second resin reservoir 122. In the following description of this embodiment, the first resin reservoir 121 and the second resin reservoir 122 are also collectively referred to as the resin reservoir 120.

Next, the operation of opening the container shown in FIG. 5 will be explained. As shown in FIGS. 5(A) and 5(B), the user can begin opening the container by grasping the extended end of the lid 130 and peeling off the lid 130 from there. can.

Here, as described above, the cohesive strength of the surface layer 114C is the bonding strength between the lid 130 and the surface layer 114C in the bonding region 140, the cohesiveness of each layer other than the surface layer 114C of the laminate 114 and the laminate 131. It is weaker than the strength and the interlayer bonding strength between each layer of the laminate 114 and the laminate 131. Therefore, when the user peels off the lid 130, the surface layer 114C pulled by the lid 130 undergoes cohesive failure at a position corresponding to the bonding region 140. As a result, a portion of the surface layer 114C is peeled off together with the lid 130, and the remaining portion of the surface layer 114C remains on the lower surface layer 114B side.

When the user further peels off the lid 130, as shown in FIG. 5(B), the cohesive failure of the surface layer 114C is interrupted at the resin pool 120, and from there on, only the lid 130 is peeled off. This is because cohesive failure of the surface layer 114C progresses along the shape of the first resin reservoir 121 in the resin reservoir 120. Near the edge 140E of the joining region 140 where the surface of the first resin reservoir 121 and the surface of the second resin reservoir 122 are separated from each other, the surface layer 114C is pulled from both sides and breaks, separating from the lid 130 side.

The container according to this embodiment is opened according to the procedure described above. If the cohesive strength of the surface layer 114C of the laminate 114 is weakened, the force with which the user peels off the lid 130 at the time of opening is reduced, and the opening becomes easier. On the other hand, before opening, in a state where the container body 110 and the lid 130 are joined to each other, the internal pressure of the internal space SP acts on the joining region 140. The bonding strength between the lid 130 and the container body 110 in the bonding region 140 can be made stronger than the cohesive strength of the surface layer 114C, so by weakening the cohesive strength of the surface layer 114C as described above. Even when opening is facilitated, the bonding strength between the lid 130 and the container body 110 remains strong to withstand high internal pressure. In addition, in the bonding region 140, stress is concentrated near the root of the first resin reservoir 121 on the concave portion 111 side, so that the bonding region 140 is able to withstand higher internal pressure than when no resin reservoir is formed. be. In this way, the container according to this embodiment can achieve both ease of opening and resistance to internal pressure. In order to maintain sealing performance, the thickness of the cohesive and peelable surface layer (surface layer 114C in the above example) is preferably 10 μm to 200 μm, more preferably 15 μm to 80 μm. Furthermore, it is not essential to form the resin reservoir 120 as explained above, and even if the resin reservoir is not formed, if the relationship between the cohesive strength and the interlayer bonding strength as described above holds, then the above example Similarly, it is possible to achieve both ease of opening and resistance to internal pressure.

Next, examples of the present invention will be described. Regarding Examples 1 to 4, Comparative Example 1, and Comparative Example 2 shown in Table 1, RPP (random polypropylene) sealant film was applied to the sheet before it was formed into a container as a lid material while changing the sealing temperature of the heat seal. The puncture pressure strength (maximum pressure at the time of bag rupture) was measured by blowing air between the sheet and the lid material at a predetermined amount. Examples 1 to 3 are examples in which the non-bonded region is made circular and the diameter φ is varied, Example 4 is an example in which the non-bonded region is made into a V-shape with rounded corners, and Comparative Example 1 is an example in which the non-bonded region is not formed. Comparative Example 2 is an example in which the vapor passage portion is formed of a mesh-like knurled seal as shown in FIG. Table 1 also shows the area S per non-bonded region. In addition, the area S in Example 4 was calculated ignoring the rounded corners of the V-shape (assuming that there are corners).

FIG. 6 is a graph showing the relationship between puncture pressure strength and seal temperature in Examples and Comparative Examples. As shown in the graph, in Comparative Example 1, the puncture pressure strength rapidly increases from 0.034 MPa to 0.111 MPa when the seal temperature is between 165°C and 175°C. That is, in the case of Comparative Example 1, if the seal temperature fluctuates within the above-mentioned temperature range of 10° C., the puncture pressure strength changes greatly, so the vaporization stability with respect to the seal temperature is low. On the other hand, in the examples of the present invention, the slope of the puncture pressure strength in the above temperature range is slightly gentler in Example 2 than in Comparative Example 1 (in Table 1, the vapor stability is evaluated as "Δ"). In Examples 1, 3, and 4 in which the diameter φ of the non-bonded region was further increased, the increase in puncture pressure strength after the sealing temperature exceeded 165°C was significantly slower than in Comparative Example 1. , the puncture pressure strength exceeds 0.10 MPa when the sealing temperature is 185°C to 195°C (in Table 1, the vapor stability is evaluated as "○"). In this way, in Examples 1 to 4, the vapor stability with respect to the seal temperature is improved compared to Comparative Example 1, so it is necessary to increase the tolerance of the seal temperature when achieving the desired puncture pressure strength. Can be done. For example, from the results of Example 2 above, in order to improve the vapor stability, the area S of each non-bonded region should be 0.1 mm ² or more, more preferably 0.15 mm ² or more. preferable.

On the other hand, in Comparative Example 2, although the vapor stability was equivalent to that of the example, the sealing performance was inferior to the example. Here, the sealing performance was evaluated by leakage evaluation (pinhole check) using a penetrating liquid. Specifically, the sealing surface was brought into contact with the penetrating liquid, and the evaluation was made based on whether the penetrating liquid exceeded the sealing surface after a predetermined period of time. Using this method, the sealing performance was evaluated with the puncture pressure strength of the seal set to 0.03 MPa and a predetermined time of 24 hours. In Examples 1 to 5 and Comparative Example 1, there was no leakage of the contents, which was marked with an "〇". Evaluation: In Comparative Example 2, there was leakage of contents and the evaluation was "x".

From the above examples, it can be seen that in the vapor passage section in which the non-bonded region is formed in the embodiment of the present invention, the desired puncture pressure strength, that is, the seal strength can be stably achieved by allowing a large sealing temperature tolerance. Recognize. As explained with reference to FIGS. 2 and 3, in the embodiment of the present invention, the non-bonded regions are isolated without touching each other, so that seal leakage can be prevented and the sealing performance of the container can be maintained. can.

Note that although the above example describes a container in which a film-like lid is joined to a container body having a cup-shaped recess, the present invention can be applied to containers of different shapes in other embodiments. be. For example, in a joining region where a first container main body and a second container main body, both of which have cup-shaped recesses, are joined to each other, a vapor passage portion in which non-joining regions are arranged as described in the above embodiment may be formed. It's okay. Further, for example, a vapor passage portion in which non-bonded regions as described in the above embodiment are arranged may be formed in the bonding region where the first container body and the second container body, both of which are film-like, are bonded to each other. Good too. In this case, the container is shaped like a bag.

Although preferred embodiments of the present invention have been described above in detail with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that those skilled in the art to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims, and these may also be considered. , it is understood that it naturally falls within the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 100... Container, 110... Container main body, 111... Recessed part, 112... Flange part, 130... Lid body, 140... Joining area, 141... Steaming part, 141A... Non-joining area, 141B... Non-joining area.

Claims (6)

comprising a first container main body and a second container main body joined to the first container main body at a joining region located at a peripheral edge of an internal space formed by the first container main body,
A plurality of mutually isolated non-bonded regions are formed in a part of the circumferential direction of the bonded region ,
The first container body is formed by a first laminate, the second container body is formed by a second laminate, and the layer structure in the bonded area and the non-bonded area of the first laminate is and the layer configurations in the bonded region and the non-bonded region of the second laminate are the same . The container according to claim 1, wherein the area of each non-bonded region is 0.1 mm ² or more. The first container body includes a cup-shaped recess forming the internal space, and a flange formed at a peripheral edge of the recess,
The container according to claim 1 or 2, wherein the second container main body is a film-like lid joined to the first container main body at the joining region located at the flange portion. The first container body is made of a laminate including at least a first layer and a second layer, and includes a recess and a flange formed at a peripheral edge of the recess, and the joining region is formed in the flange,
The bonding strength between the second container body and the second layer is stronger than the interlayer bonding strength between the second layer and the first layer,
The container according to claim 1 or 2, wherein the missing portion of the second layer is formed closer to the recess than the bonding region. The first container body includes a recess and a flange formed at a peripheral edge of the recess, the joining region being formed at the flange,
The first container body is made of a laminate including at least a first layer and a second layer bonded to the first layer and facing the bonding area,
The second container body is made of a laminate including at least a third layer facing the bonding area and a fourth layer bonded to the third layer,
Either the second layer or the third layer is a cohesive failure layer, and the cohesive strength of the cohesive failure layer is the bonding strength between the second container body and the first container body, than the cohesive strength of each layer up to the fourth layer other than the cohesive failure layer, and the interlayer bonding strength between the first layer and the second layer and between the third layer and the fourth layer. 3. A container according to claim 1 or claim 2, which is weak. A first resin reservoir part, which is made of the resin forming the first layer and the second layer and has a knob-shaped cross section tilted toward the recess side, is provided at the edge of the joint area on the recess side, and a first resin reservoir part of the third layer 6. The container according to claim 5, wherein a second resin reservoir is formed of resin and has a knob-like cross section and is located closer to the recess than the first resin reservoir.

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