JP2019094082A - Bag-like packaging body - Google Patents

Abstract

To provide a packaging body for heating contents in a sealed state in a microwave oven and the like and releasing steam, in which an adhesive layer and a printing ink layer are not exposed even in the case where a separation seal line is peeled by heating and a content storage room and a steam releasing part are communicated with each other, and, therefore, which has no risk of the contents coming into contact with the adhesive layer and the printing ink layer.SOLUTION: A sealant film 13 is made to be a three-layer structure, and an intermediate layer 13b is made to be a layer which can be peeled by cohesive failure. When heated by a microwave oven and the like, the intermediate layer is subject to cohesion failure by an internal pressure. At this time, as an adhesive layer 12 and a printing ink layer are coated by an outside layer 13a, there is no risk of the contents coming into contact with them.SELECTED DRAWING: Figure 1

Description

  The present invention relates to, for example, a bag-like package which seals a food content and cooks it with a microwave oven or the like in the sealed state.

  A bag-like package which is cooked by microwave heating while the food content is sealed is known. In such a package, water vapor is generated from the food contents along with microwave heating and the internal pressure is increased. Therefore, in order to prevent the bag from being broken by the internal pressure, a technique for releasing the water vapor to the outside of the package Various devices are piled up.

  For example, in Patent Documents 1 and 2, a vapor discharge part B is provided in a part of the bag-like package, and further, an isolation seal line b separating the vapor discharge part B and the contents storage chamber A from each other. Are provided (see FIG. 4). The cross section in the periphery of the vapor | steam discharge part B of this package body, ie, the XX in FIG. 4, is shown to Fig.5 (a).

  As can be seen from FIG. 5 (a), the front and back films 10, 20 constituting the package 100 have the sealant film 13 on the inner surface side of the base films 11, 21 via the adhesive layers 12, 22. The separating seal line b is formed by heat-sealing the sealant films 13 'and 23' of these front and back films. In addition, the vapor discharge portion B is configured by a through hole that penetrates the front side film 10.

  Then, when microwave heating is performed, water vapor is generated from the contents and the internal pressure of the content storage chamber A is increased. Therefore, as shown in FIG. 5B, the sealant film 13 'at the position of the isolation seal line b due to the internal pressure. Is broken and peeled off from the adhesive layer 12, and the content storage chamber A and the vapor discharge part B communicate with each other. The water vapor in the content storage chamber A is discharged to the outside of the package through the communication portion and the vapor discharge portion B.

JP, 2002-249176, A JP 2003-192042 A

  However, in this package, the base film 1 and the adhesive layer 12 peel off during microwave heating, so the adhesive layer 12 is exposed on the inner surface of the package as shown in FIG. 5 (b). And there was a risk of contact with the contents. Moreover, when printing is given to the inner surface of the base film 1, this printing ink layer may be taken up by the adhesive layer 12, and it may peel between a printing ink layer and the base film 1. . In this case, the printing ink layer may be exposed to the inner surface of the package and may come in contact with the contents.

  In addition, the sealant film 13 ′ and the adhesive layer 112 may peel off, and in this case, the adhesive layer 12 may be exposed to the inner surface of the package and may be in contact with the contents.

The present invention has been made based on the above circumstances, and the adhesive layer and the printing ink layer are exposed even when the content storage chamber and the vapor discharge portion communicate with each other because the separation seal line is peeled off by heating. It is therefore an object of the present invention to provide a package which does not cause contact between the adhesive layer or the printing ink layer and the contents.

That is, according to the first aspect of the present invention, the content storage chamber is sealed by overlapping the front and back films and sealing at the periphery thereof, and a vapor discharge part is partially provided, and these content storage chambers A separation seal line for separating the two from each other, and the separation seal line is peeled off by internal pressure due to heating to communicate the content storage chamber with the steam discharge portion, and the content storage chamber In the package which discharges the water vapor generated in the outside from the steam discharge part,
The front and back films are formed by laminating a base film and a sealant film,
The sealant film has a three-layer structure, and the intermediate layer is composed of a layer capable of cohesive failure.

  Next, invention of Claim 2 is a package body of Claim 1 in which the said base film and sealant film are laminated | stacked through an adhesive bond layer.

  Next, the invention according to claim 3 is the package according to claim 1 or 2, wherein printing is applied to the inner surface side of the base film.

  Next, the invention according to claim 4 is characterized in that the vapor discharge part is one in which the separation seal line seals sealant films of the films on the front and back sides. It is a package body described in.

  Next, the invention according to claim 5 is the package according to any one of claims 1 to 4, characterized in that the vapor discharge part comprises a through hole penetrating at least one of the front and back films. It is a body.

  According to the present invention, since the sealant film has a three-layer structure and the intermediate layer is formed of a layer capable of cohesive failure, when the package in a sealed state is heated by a microwave oven or the like, the internal pressure is The middle layer cohesively breaks and opens the water vapor discharge path. And since the inside of this discharge way is covered with the outside layer located in the substrate film side among the three layers which constitute the sealant film, the adhesive layer between the substrate film and the sealant film and the printing ink The layers are not exposed, and therefore there is no risk of contact between the adhesive layer and the printing ink layer and the contents.

FIG. 1 is a cross-sectional view of an essential part according to a specific example of the package of the present invention. FIG. 2 is a sectional view of an essential part showing a heated state of the specific example of the package of the present invention. FIG. 3 is a plan view showing a specific example of the package. FIG. 4 is a plan view showing a specific example of the package. FIG. 5 relates to a conventional package, and FIG. 5 (a) is a cross-sectional view of the main part thereof, and FIG. 5 (b) is a cross-sectional view of the main part showing a heated state of the package.

  The package of the present invention may be any form of package. For example, a four-way seal bag, a three-way seal bag, a standing pouch, a gusset bag, etc. In any case, the package of the present invention has a front side film and a back side film, and it is necessary to form and seal a content storage chamber by sealing at the periphery thereof.

In the case of a four-sided sealed bag, as shown in FIG. 4, its appearance is similar to that of a conventional package.
As can be seen from FIG. 4, the front film 10 and the back film 20 are superimposed on one another, and the content storage chamber A is sealed by sealing them together at their peripheries. In the figure, a indicates a peripheral seal line.

  Further, the package 100 of the present invention is provided with a vapor discharge part B separately from the content storage chamber A, and an isolation seal line b is provided between the content storage chamber A and the vapor discharge part B. It is provided. The isolation seal line b is a line formed by heat sealing the front side film 10 and the back side film 20 to each other, and the content storage room A and the vapor discharge part B are isolated from each other by the isolation seal line b. There is. In addition, in this example, it is comprised by the annular | circular shaped line surrounding the vapor | steam discharge part B. As shown in FIG. Also, in this example, the isolation seal line b is provided at a position away from the peripheral seal line a, but the isolation seal line b is provided adjacent to the inside of the peripheral seal line a so that both are continuous. It is also good. Moreover, as described below, it is also possible to use a part of the peripheral seal line a as the isolation seal line b.

  The vapor | steam discharge | release part B can be comprised by the through-hole which penetrates the one or both of the front side film 10 and the back side film 20, for example. Further, the steam discharge portion B can be configured by a weakening line such as a perforation which is broken by the pressure of the steam generated at the time of heating. When the vapor discharge portion B is configured by a weakening line, it is desirable that the weakening line has a closed curve shape.

  Moreover, as shown in FIG. 3, it is also possible to provide the steam discharge part B in a part of peripheral seal line a. In this case, the steam discharging portion B can be configured by a notch or a cut provided on the peripheral seal line a from the outer periphery of the package 100. And, in this case, it is possible to use a part of the peripheral seal line a which is adjacent to the vapor discharge part B as the isolation seal line b.

  By the way, as shown in FIG. 1, the front side film 10 is configured by adhesively laminating the sealant film 13 on the inner surface of the base film 11 via the adhesive layer 12. The back film 20 is also the same, and is configured by adhesively laminating the sealant film 23 on the inner surface of the base film 21 via the adhesive layer 22.

  As the base film 11, a film having mechanical strength and dimensional stability can be preferably used. For example, various biaxially stretched films. Examples of the material include polyester, polypropylene, polystyrene, nylon, polycarbonate, polyacrylonitrile, polyimide and the like. Moreover, the film of these various materials may be laminated | stacked, and the film of the multilayer structure which laminated | stacked the other film may be sufficient, and it is good also considering the film which provided the inorganic vapor deposition layer as the base film 11. As the inorganic substance used for the inorganic vapor deposition layer, oxidized metals such as silicon oxide, aluminum oxide, magnesium oxide, calcium oxide, potassium oxide, tin oxide, sodium oxide, boron oxide, titanium oxide, lead oxide, zirconium oxide, yttrium oxide and the like Things can be used. Among them, silicon oxide, aluminum oxide and magnesium oxide are preferable in terms of productivity and cost. The base film 11 containing the metal deposition layer or the inorganic deposition layer in the layer configuration is also excellent in barrier properties such as water vapor and oxygen gas.

  The base film 11 can also be printed. The printing ink layer is preferably provided on the inner surface side of the bag-like package 100 in order to prevent abrasion of the printing ink layer.

  The sealant films 13 and 23 need to have a three-layer structure. Further, among these three layers, the intermediate layers 13b and 23b located in the middle need to be capable of cohesive failure. The other two layers, ie, the outer layers 13a and 23a located on the base film 11 side and the inner layers 13c and 23c exposed to the inner surface of the package 100 do not have to be capable of cohesive failure, but rather, do not be cohesive failure. Is desirable.

  All of the intermediate layers 13b and 23b, the outer layers 13a and 23a, and the inner layers 13c and 23c can be mainly composed of a polyolefin resin.

  The intermediate layers 13b and 23b can be configured by mixing two types of polyolefin resins which are mutually incompatible. For example, a mixture of low density polyethylene and polypropylene. It can also be composed of a mixture of low density polyethylene and polybutene. Or it can also be comprised by the composition which mix | blended inorganic powder with polyolefin resin. In any case, when the package 100 is heated, the heat and the internal pressure cause cohesive failure at the interface between the components which are less compatible with each other.

  On the other hand, it is desirable that the outer layers 13a and 23a and the inner layers 13c and 23c be formed of a single polyolefin resin. The outer layers 13a and 23a and the inner layers 13c and 23c can be formed by mixing a plurality of types of polyolefin resins, but the resins constituting these layers 13a, 23a, 13c and 23c are excellent in mutual compatibility, It is desirable that it does not cause cohesive failure. Examples of polyolefin resins that can be used for the outer layers 13a and 23a and the inner layers 13c and 23c include, for example, low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, ethylene-vinyl acetate copolymer (EVA And ethylene-methacrylic acid copolymer (EMAA), ethylene-ethyl acrylate copolymer (EAA), ionomer, polypropylene and the like.

  It is desirable that the outer layer 13a, the intermediate layer 13b, and the inner layer 13c be stacked without using an adhesive. For example, a sealant film 13 in which the three layers 13a, 13b and 13c are in direct contact with each other can be manufactured by a three-layer coextrusion film forming method without an adhesive. The sealant film 23 is also the same.

  Next, the base film 11 and the sealant film 13 can be adhesively laminated by, for example, a dry lamination method. The adhesive may be a known one, for example, a two-component urethane adhesive for dry lamination. Similarly, the back film 20 can be manufactured by adhesively laminating the base film 21 and the sealant film 23.

  And the method of making the package 100 into a bag using the front side film 10 and the back side film 20 which were manufactured in this way is well-known. That is, first, for example, after forming the vapor discharge portion B on the front side film 10, the front side film 10 and the back side film 20 are overlapped and heat sealed to form a peripheral seal line excluding an opening for content storage It is sufficient to form a and the isolated seal line b. The peripheral seal line a and the isolation seal line b are both formed by heat sealing the inner layer 13 c of the front film 10 and the inner layer 23 c of the back film 20. The peripheral seal line a and the isolation seal line b can be simultaneously formed by a single sealing process. Finally, the contents can be stored in the content storage unit A from the opening, and the opening can be sealed by heat sealing. The package 100 shown in FIG. 1 is a four-way seal bag manufactured through such a process.

  In addition, it is also possible to form the vapor | steam discharge | release part B after formation of the peripheral seal line a and the isolation seal line b. That is, first, the front side film 10 and the back side film 20 are overlapped and heat sealed to form the peripheral seal line a and the isolation seal line b, and then the through holes are formed in the portion surrounded by the isolation seal line b By providing a weakening line such as a perforation, the steam discharge portion B can be formed. Further, in the case where the vapor discharge part B is provided at the end edge of the package 100 as shown in FIG. 3, after forming the peripheral seal line a, it is sufficient to provide a notch or a cut at the outer part of the peripheral seal line a. . In addition, it is also possible to form the steam discharge part B simultaneously with the formation of the peripheral seal line a and the isolation seal line b.

  When the package 100 manufactured in this manner is heated in, for example, a microwave oven while the contents are sealed in the content storage unit A, as shown in FIG. 2, the inner layer 13c is located at the position of the isolation seal line b. The fracture occurs, and the intermediate layer 13 b is cohesively fractured, and the content storage chamber A and the vapor discharge part B communicate with each other. The water vapor in the content storage chamber A is discharged to the outside of the package through the communication portion and the vapor discharge portion B. At this time, since the adhesive layer 12 is covered with the outer layer 13a and a part of the cohesively broken intermediate layer 13b, the adhesive layer 12 does not touch the released water vapor, and the contents The adhesive layer 12 does not touch. Moreover, even when printing is performed on the base film 11, the printing ink layer does not come in contact with water vapor or contents.

Example 1
A 25 μm thick polyamide film was used as the base film 11, 21 and printing was performed in a pattern on the inner surface side.

  In addition, polypropylene is used as a resin forming the outer layers 13a and 23a and the inner layers 13c and 23c, and a mixed resin of polyethylene and polypropylene is used as a resin forming the intermediate layers 13b and 23b. A three-layered sealant film 13 was produced by the membrane method. The thickness of the sealant film 13 is 50 μm, and the thickness ratio of the outer layers 13a and 23a, the intermediate layers 13b and 23b, and the inner layers 13c and 23c is 1: 1: 1.

  And these base films 11 and 21 and the sealant films 13 and 23 were dry-laminated, and the films 10 and 20 of front and back were manufactured. The base films 11 and 21 were disposed such that the printing ink layers faced the sealant films 13 and 23.

  Next, after providing a through hole in the front side film 10 to form the vapor discharge part B, the front side film 10 and the back side film 20 are overlapped, heat sealed at a predetermined position, and the peripheral seal line a excluding the opening and the vapor An annular isolated seal line b surrounding the discharge part B was formed.

  Finally, after 50 g of water was used as a content, the content was stored from the opening, and the opening was heat sealed to seal the content storage portion A to obtain a bag-like package.

(Example 2)
A packaging bag is manufactured in the same manner as in Example 1 except that the thickness ratio of the outer layer 13a, 23a, the intermediate layer 13b, 23b and the inner layer 13c, 23c is 1: 1: 2, and the contents are sealed It was made in the shape of a round package.

(Example 3)
A packaging bag is manufactured in the same manner as in Example 1 except that the thickness ratio of the outer layers 13a and 23a, the intermediate layers 13b and 23b, and the inner layers 13c and 23c is 1: 2: 1, and the contents are sealed It was made in the shape of a round package.

(Example 4)
A packaging bag is manufactured in the same manner as in Example 1 except that the thickness ratio of the outer layers 13a and 23a, the intermediate layers 13b and 23b, and the inner layers 13c and 23c is 2: 1: 1, and the contents are sealed It was made in the shape of a round package.

(Example 5)
The thickness ratio of the outer layers 13a and 23a, the intermediate layers 13b and 23b, and the inner layers 13c and 23c is
A packaging bag was produced in the same manner as in Example 1 except that 1: 2: 2 was used, and the contents were sealed to form a bag-like package.

(Example 6)
A packaging bag is manufactured in the same manner as in Example 1 except that the thickness ratio of the outer layers 13a and 23a, the intermediate layers 13b and 23b, and the inner layers 13c and 23c is 2: 2: 1. It was made in the shape of a round package.

(Comparative example)
A package was manufactured in the same manner as in Example 1 except that a film having a single layer structure was used as the sealant film 13, 23, and the contents were sealed to form a bag-like package. The material of the sealant films 13 and 23 is linear low density polyethylene.

(Evaluation)
After heating the packages of Examples 1 to 6 and Comparative Example with a microwave oven, the peeling position of the vapor discharge part B and the presence or absence of the bag were examined. In addition, heating conditions are 1000 W and 1 minute.

  The results are shown in Table 1. In the table, “Ny / ink” means that peeling has occurred on the boundary surface between the polyamide film constituting the base film 11 and the printing ink layer.

  As can be seen from this result, the packages of Examples 1 to 6 and the Comparative Example had no broken bags, and the generated water vapor was sufficiently released from the steam releasing part B, but in the Comparative Example, printing was performed with the polyamide film Peeling occurred at the interface with the ink layer, and therefore, it was confirmed that the printing ink layer and the adhesive layer 12 were in contact with the contents. On the other hand, in Examples 1 to 6, the peeling is caused by the cohesive failure of the intermediate layer 13b. Therefore, the printing ink layer and the adhesive layer 12 are covered with the outer layer 13a and a part of the cohesively broken intermediate layer 13b. And the printing ink layer did not come into contact with the contents.

100: package 10: front side film 11: base film 12: adhesive layer 13: sealant film 13a: outer layer 13b: middle layer 13c: inner layer 20: back film 21: base film 22: adhesive layer 23: Sealant film 23a: outer layer 23b: middle layer 23c: inner layer A: content storage chamber B: vapor discharge part a: peripheral seal line b: isolated seal line

Claims (5)

The contents storage chamber is sealed by overlapping the front and back films and sealing at the periphery, and a vapor discharge part is provided in part, and both are isolated between the content storage room and the vapor discharge part The separation seal line is peeled off by internal pressure by heating to connect the content storage chamber and the vapor discharge part, and the water vapor generated in the content storage chamber is transferred from the vapor discharge part to the outside In the package to be released,
The front and back films are formed by laminating a base film and a sealant film,
A packaging body characterized in that the sealant film has a three-layer structure, and the intermediate layer is constituted of a layer capable of cohesive failure.   The package according to claim 1, wherein the base film and the sealant film are laminated via an adhesive layer.   The package according to claim 1 or 2, wherein printing is applied to the inner surface side of the base film.   The package according to any one of claims 1 to 3, wherein the separation sealing line seals sealant films of the film on the front and back.   The package according to any one of claims 1 to 4, wherein the vapor discharge part comprises a through hole penetrating at least one of the front and back films.

Images