JP2019163080A - Bag and method for manufacturing bag - Google Patents

Abstract

To suppress damaging of a laminate that constitutes a bag.SOLUTION: The bag having a storage part comprises: a laminate that is positioned in the inner surface of the bag and includes a sealant film having a single layer and at least one plastic film positioned closer to an outer surface side than the sealant film; and a seal part that joins the inner surfaces of a pair of laminates. The seal part has an outer edge seal positioned at the outer edge of the bag, and a steam vent seal positioned closer to the center point side of the storage part than the outer edge seal and peeled by a pressure increase in the storage part. The sealing strength of the seal part at 25°C is equal to or lower than 60N, and the sealing strength of the seal part at 100°C is equal to or lower than 23N.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a bag having a vapor vent seal portion that peels off due to an increase in internal pressure and a method for manufacturing the bag.

  Conventionally, many cooked or semi-cooked liquids, viscous bodies, or contents in which liquid and solid are mixed are filled and sealed in bags made of plastic laminates. In the bag, the non-seal part to which the laminated bodies are not joined constitutes an accommodation part in which the contents are accommodated. Moreover, the sealing part to which the laminated bodies are joined has sealed the accommodating part. The contents are, for example, cooked foods such as curry, stew, and soup. The contents are heated by a microwave oven or the like while being contained in a bag.

  By the way, if the contents accommodated in the sealed bag are heated using a microwave oven, the moisture contained in the contents evaporates with the heating, and the pressure in the accommodating portion increases. When the pressure in the bag storage portion increases, the bag may rupture and the contents may be scattered to contaminate the inside of the microwave oven. In consideration of such problems, for example, Patent Document 1 proposes to provide a mechanism for automatically communicating the housing portion with the outside when the pressure in the housing portion increases and releasing the vapor in the housing portion to the outside. ing. The mechanism includes a steam release seal that peels off as the pressure in the housing increases.

JP2015-120550A

  As a result of extensive research conducted by the present inventors, in the conventional bag, the pressure and temperature of the housing part when the steam release seal part peels off become excessively high, so that holes and wrinkles are formed in the laminate constituting the bag. It was found that damage such as

  An object of this invention is to provide the bag which can solve such a subject effectively.

  The present invention is a bag having a housing portion, and includes a sealant film that is located on the inner surface of the bag and is formed of a single layer, and at least one plastic film that is located on the outer surface side of the sealant film. A laminate, and a seal portion that joins the inner surfaces of the pair of laminates, the seal portion being an outer edge seal portion located at an outer edge of the bag, and the center of the housing portion more than the outer edge seal portion A steam release seal portion that is located on the point side and peels off due to an increase in the pressure of the housing portion, and the seal strength of the seal portion at 25 ° C. is 60 N or less, and the seal at 100 ° C. This is a bag having a seal strength of 23 N or less.

  In the bag according to the present invention, the product of the tensile elastic modulus (MPa) of the sealant film and the thickness (μm) of the sealant film in the flow direction may be 35000 or more.

  In the bag according to the present invention, a seal strength of the seal portion at 25 ° C. may be 55 N or less.

  In the bag according to the present invention, the seal strength of the seal portion at 25 ° C. may be 40 N or more, or 45 N or more.

  In the bag according to the present invention, the sealant film may contain a propylene / ethylene block copolymer as a main component.

  In the bag according to the present invention, the sealant film may contain a propylene / ethylene block copolymer as a main component and an α-olefin copolymer.

  The bag according to the present invention further includes a non-seal part separated from the housing part by the steam release seal part, and the non-seal part is located at a position closer to a center point of the housing part than the outer edge seal part. It may spread to reach the outer edge of.

  In the bag according to the present invention, the peeling pressure of the steam release seal portion may be 133 kPa or less, or 130 kPa or less.

  A method for manufacturing a bag according to the present invention is a method for manufacturing a bag having a housing portion, and includes a sealant film positioned on an inner surface of the bag, and at least one plastic film positioned on an outer surface side of the sealant film. A step of preparing a laminate including the heat sealing of the inner surfaces of the pair of laminates at a predetermined sealing temperature, and an outer edge seal portion positioned on an outer edge of the bag; A sealing step of forming a seal portion having a steam release seal portion that is located on the center point side and peels off due to an increase in the pressure of the housing portion; and cutting the laminate in which the seal portion is formed to cut a plurality of A step of obtaining the bag, and the sealing temperature of the sealing step is set so that a sealing strength of the seal portion at 100 ° C. is 23 N or less. It is a production method.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that damage, such as a hole, arises in the laminated body which comprises a bag.

It is a front view which shows the bag in embodiment of this invention. It is sectional drawing which shows the case where the bag shown in FIG. 1 is seen along II-II line. It is sectional drawing which shows an example of the laminated constitution of the laminated body which comprises a bag. It is a front view which shows the bag of the state by which the upper part was sealed. It is sectional drawing which shows the test piece for measuring seal strength. It is a figure which shows an example of the measuring method of seal strength. It is a figure which shows the change of the tensile stress with respect to the space | interval between a pair of grips which pulls a test piece in order to measure seal strength. It is a figure which shows an example of the method of measuring the pressure of a accommodating part. It is a front view which shows one modification of a bag. It is a front view which shows one modification of a bag. It is a front view which shows one modification of a bag. It is a front view which shows one modification of a bag. It is a table | surface which shows the evaluation result of the relationship between seal temperature and seal strength. It is a graph which shows the evaluation result of the relationship between seal temperature and seal strength. It is a table | surface which shows the evaluation result of an Example and a comparative example.

  An embodiment of the present invention will be described with reference to FIGS. Note that, in the drawings attached to the present specification, for convenience of illustration and understanding, the scale and vertical / horizontal dimension ratios are appropriately changed and exaggerated from those of the actual ones.

  In addition, as used in this specification, the shape and geometric conditions and the degree thereof are specified, for example, terms such as “parallel”, “orthogonal”, “identical”, length and angle values, etc. are strictly Without being bound by meaning, it should be interpreted including the extent to which similar functions can be expected.

  FIG. 1 is a front view showing a bag 10 according to the present embodiment. The bag 10 includes a storage portion 17 that stores the contents. In addition, in FIG. 1, the bag 10 of the state before the contents are accommodated is shown. The bag 10 by this Embodiment is comprised so that it can be conveniently used as a pouch for microwave ovens in which the contents are heated with a microwave oven.

  As shown in FIG. 1, the bag 10 according to the present embodiment includes a steam release mechanism 20 for escaping steam generated when the contents contained in the bag 10 are heated to the outside. The steam release mechanism 20 allows the inside and the outside of the bag 10 to communicate with each other when the pressure of the steam reaches a predetermined value or more to escape the steam, and suppresses the steam from being released from a place other than the steam release mechanism 20. ,It is configured. Hereinafter, the configuration of the bag 10 will be described.

In the present embodiment, the bag 10 is a gusseted bag configured to be able to stand on its own. The bag 10 includes an upper portion 11, a lower portion 12, and a pair of side portions 13, and has a substantially rectangular outline in a front view. It should be noted that names such as “upper”, “lower” and “side”, and terms such as “upper” and “lower” refer to a bag based on the state in which the bag 10 is self-supporting with the gusset portion down. It is only a relative representation of the position and direction of 10 and its components. The attitude | position at the time of transport of the bag 10 or use is not limited by the name and terminology in this specification.

  In the present embodiment, the width direction of the bag 10 is also referred to as a first direction D1. The pair of side portions 13 described above face each other in the first direction D1. A direction orthogonal to the first direction D1 is also referred to as a second direction D2. In the bag 10 of the present embodiment, a usage pattern is assumed in which, after the contents of the bag 10 are heated by a microwave oven, the bag 10 is opened by the consumer tearing the bag 10 along the first direction D1. Has been.

  As shown in FIG. 1, the bag 10 includes a surface film 14 that constitutes the front surface, a back film 15 that constitutes the back surface, and a lower film 16 that constitutes the lower portion 12. The lower film 16 is disposed between the front film 14 and the back film 15 in a state where the lower film 16 is folded at the folded portion 16f.

  In addition, the term “surface film”, “back film” and “lower film” described above is merely a partition of each film according to the positional relationship, and the method of providing a film when manufacturing the bag 10 It is not limited by the above terms. For example, the bag 10 may be manufactured using one film in which the front film 14, the back film 15, and the lower film 16 are continuously provided, or one sheet in which the front film 14 and the lower film 16 are continuously provided. It may be manufactured using a total of two films, a film and one back film 15, and a total of three films, one surface film 14, one back film 15, and one lower film 16. May be used.

  As for the surface film 14, the back film 15, and the lower film 16, inner surfaces are joined by the seal part. In the plan view of the bag 10 shown in FIG. 1 and the like, the seal portion is hatched.

  As shown in FIG. 1, the seal portion includes an outer edge seal portion extending along the outer edge of the bag 10 and a steam vent seal portion 20 a constituting the steam vent mechanism 20. The outer edge seal portion includes a lower seal portion 12 a extending in the lower portion 12 and a pair of side seal portions 13 a extending along the pair of side portions 13. In addition, in the bag 10 in a state before the contents are accommodated, as shown in FIG. 1, the upper portion 11 of the bag 10 is an opening 11b. After the contents are stored in the bag 10, the inner surface of the front film 14 and the inner surface of the back film 15 are joined at the upper portion 11, whereby an upper seal portion is formed and the bag 10 is sealed.

  The side seal portion 13a, the steam release seal portion 20a, and the upper seal portion are seal portions configured by joining the inner surface of the front film 14 and the inner surface of the back film 15. On the other hand, the lower seal portion 12a is formed by bonding the inner surface of the surface film 14 and the inner surface of the lower film 16, and by bonding the inner surface of the back film 15 and the inner surface of the lower film 16. Including a configured seal.

  As long as the opposing films can be bonded to each other and the bag 10 can be sealed, the method for forming the seal portion is not particularly limited. For example, the sealing portion may be formed by melting the inner surfaces of the film by heating or the like and welding the inner surfaces, that is, by heat sealing. Or you may form a seal | sticker part by adhere | attaching the inner surfaces of the opposing film using an adhesive agent etc.

Venting mechanism following describes the structure of venting mechanism 20. FIG. 2 is a cross-sectional view showing a case where the vapor venting mechanism 20 of the bag 10 shown in FIG. 1 is viewed along the line II-II.

  The steam release seal portion 20 a of the steam release mechanism 20 has a shape that is easily peeled off as the pressure in the housing portion 17 increases. For example, the steam release seal portion 20 a has a shape protruding from the side seal portion 13 a toward the inside of the bag 10. Thereby, when the pressure of the accommodating part 17 increases, the force added to the steam release seal part 20a can be made larger than the force applied to the side seal part 13a. Moreover, the width | variety of the steam release seal | sticker part 20a is smaller than the width | variety of the side part seal | sticker part 13a. Moreover, as shown in FIG.1 and FIG.2, the non-seal part 20b isolated from the accommodating part 17 by the steam release seal part 20a is formed between the steam release seal part 20a and the outer edge of the side part 13. Yes.

  When the contents of the bag 10 are heated, when the water contained in the contents evaporates and the pressure in the container 17 increases, the bag 10 expands around the center point C of the container 17. In this case, a force in a direction from the center point C toward the seal portion is applied to the seal portions such as the side seal portion 13a and the steam release seal portion 20a. The force applied to each position of the seal portion increases as the distance from the center point C decreases. The above-mentioned steam vent seal portion 20a protrudes from the side seal portion 13a toward the accommodating portion 17 side. Therefore, the force applied to the steam vent seal portion 20a is larger than the force applied to the side seal portion 13a. . Therefore, compared with the side seal part 13a, in the steam release seal part 20a, it is possible to easily cause communication between the housing part 17 and the outside due to peeling of the seal part.

  In the example shown in FIGS. 1 and 2, the non-seal portion 20 b of the steam release mechanism 20 extends so as to reach the side edge of the bag 10. Therefore, the part which overlaps with the non-seal part 20b among the side edges of the bag 10 is opened. In this case, the steam that has flowed into the non-seal portion 20b from the housing portion 17 through the peeled portion of the steam release seal portion 20a may smoothly escape to the outside of the bag 10 through the opening portion 20p on the side edge of the bag 10. it can. In the following description, a bag of a type in which the non-seal portion 20b of the steam release mechanism 20 extends to the outer edge such as the side edge of the bag 10 as shown in FIGS. Also referred to as a type 1 bag.

  By the way, when the contents of the bag 10 are heated using a microwave oven or the like, a part of the contents may jump up and reach the inner surface of the laminate constituting the bag 10. When the contents attached to the inner surface of the laminate contain moisture, the contents attached to the inner surface of the laminate are further heated by the microwave oven. In this case, it is conceivable that the temperature of the laminated body in contact with the contents also rises, and holes are formed in the laminated body or wrinkles are formed in the laminated body.

  In consideration of such a problem, in the present embodiment, the seal portion is configured so that the seal strength of the seal portion of the bag 10 heated to a high temperature has a moderately low value. For example, the seal portion is configured such that the seal strength (hereinafter also referred to as hot seal strength) of the seal portion of the bag 10 at 100 ° C. is 23 N or less. In this case, when the contents of the bag 10 are heated using a microwave oven or the like, the vapor vent seal portion 20a of the seal portion is easily peeled based on the force received from the pressure of water vapor generated in the storage portion 17. That is, the steam release seal portion 20a is peeled off at a lower pressure. Thereby, before the temperature of the contents attached to the inner surface of the bag 10 becomes excessively high, the steam release seal part 20a is peeled off to release the steam in the storage part 17 to the outside, and the pressure of the storage part 17 and The temperature can be lowered. Thereby, it is possible to suppress the occurrence of damage such as holes and wrinkles in the laminated body of the bags 10. In the following description, the pressure of the housing portion 17 when the steam release seal portion 20a peels and the housing portion 17 communicates with the outside of the bag 10 is also referred to as a peeling pressure.

  As a method for configuring the seal portion so that the hot seal strength of the seal portion of the bag 10 is 23 N or less, in this embodiment, the seal of the seal portion of the bag 10 at a low temperature, for example, at 25 ° C. A method of appropriately managing strength (hereinafter also referred to as room temperature seal strength) is adopted. As a result of intensive research by the present inventors, in the bag 10 of the present embodiment, the hot seal strength of the seal portion is 23 N or less by configuring the seal portion so that the normal temperature seal strength is 60 N or less. Found that it can be. Based on such knowledge, in this embodiment, the bag 10 having a seal portion having a hot seal strength of 23 N or less is set by setting the configuration conditions of the seal portion so that the normal temperature seal strength is 60 N or less. Can be manufactured. For this reason, the bag 10 in which the occurrence of damage such as holes and wrinkles is suppressed can be stably provided.

  Factors that determine the normal temperature seal strength of the seal portion include mechanical properties and thickness of a sealant film, which will be described later, located on the inner surface of the laminate. Moreover, when forming seal parts, such as the steam removal seal part 20a, by the heat seal process, the seal strength of the seal part of the bag 10 can be changed depending on the conditions of the heat seal process such as temperature. Moreover, the sealing strength of the seal part of the bag 10 can also be changed by a sterilization process such as a boil process or a retort process. In the present embodiment, by appropriately adjusting and considering these factors, a seal portion having a normal temperature seal strength of 60 N or less is formed. When the bag 10 is subjected to processing such as boil processing or retort processing, the sealing strength of the sealing portion of the bag 10 is the sealing strength of the sealing portion of the bag 10 after processing unless otherwise specified. Means.

  The retort process is a process of filling the bag 10 with the contents and sealing the bag 10 and then heating the bag 10 in a pressurized state using steam or heated hot water. The temperature of retort processing is 120 degreeC or more, for example. The boil process is a process of filling the bag 10 with the contents and sealing the bag 10 and then bathing the bag 10 under atmospheric pressure. The temperature of boil processing is 90 degreeC or more and 100 degrees C or less, for example.

  Moreover, as a factor which determines the peeling pressure of the steam release seal | sticker part 20a, the shape of a steam release seal | sticker part 20a, a dimension, hot seal strength, etc. can be mentioned. The peeling pressure of the steam release seal portion 20a is preferably 133 kPa or less, more preferably 130 kPa or less, and still more preferably 126 kPa or less.

  If the peeling pressure of the vapor vent seal part 20a is too low, the vapor vent seal part 20a peels off before the contents are sufficiently heated and pressurized, and the pressure and temperature of the housing part 17 decrease. It is possible to end up. Considering this point, the peeling pressure of the steam release seal portion 20a is preferably 105 kPa or more, more preferably 110 kPa or more.

Next, the layer structure of the front film 14 and the back film 15 will be described. FIG. 3 is a cross-sectional view showing an example of the layer configuration of the laminate 30 that constitutes the front film 14 and the back film 15.

  As shown in FIG. 3, the laminate 30 includes at least a first plastic film 40, a first adhesive layer 45, a second plastic film 50, a second adhesive layer 55, and a sealant film 70 in this order. The first plastic film 40 is located on the outer surface 30y side, and the sealant film 70 is located on the inner surface 30x side opposite to the outer surface 30y. The inner surface 30x is a surface located on the accommodating portion 17 side.

  Hereinafter, each layer of the laminate 30 will be described in detail.

(First plastic film)
The first plastic film 40 is, for example, a stretched plastic film that is stretched in a predetermined direction. The first plastic film 40 functions as a base material layer for giving the laminate 30 a predetermined strength. The first plastic film 40 may be a uniaxially stretched film stretched in a predetermined direction, or may be a biaxially stretched film stretched in a predetermined two directions. The extending direction of the first plastic film 40 is not particularly limited. For example, the 1st plastic film 40 may be extended | stretched in the direction where the side part 13 is extended, and may be extended | stretched in the direction orthogonal to the direction where the side part 13 is extended. The draw ratio of the first plastic film 40 is, for example, 1.05 times or more.

  The first plastic film 40 includes, for example, polyester as a main component. For example, the first plastic film 40 includes 51% by mass or more of polyester. Examples of the polyester include polyethylene terephthalate (hereinafter also referred to as PET), polybutylene terephthalate (hereinafter also referred to as PBT), and the like. In addition, 51 mass% or more polyester in the 1st plastic film 40 may be comprised by one type of polyester, and may be comprised by two or more types of polyester.

  When the 1st plastic film 40 contains polyester as a main component, the thickness of the 1st plastic film 40 becomes like this. Preferably it is 9 micrometers or more, More preferably, it is 12 micrometers or more. Moreover, when the 1st plastic film 40 contains polyester as a main component, the thickness of the 1st plastic film 40 becomes like this. Preferably it is 25 micrometers or less, More preferably, it is 20 micrometers or less. By setting the thickness of the first plastic film 40 to 9 μm or more, the first plastic film 40 has sufficient strength. Moreover, the 1st plastic film 40 comes to show the outstanding moldability by making the thickness of the 1st plastic film 40 into 25 micrometers or less. For this reason, the process which processes the laminated body 30 and manufactures the bag 10 can be implemented efficiently.

  The first plastic film 40 may contain polyamide as a main component. For example, the first plastic film 40 includes 51% by mass or more of polyamide. Examples of polyamide systems include aliphatic polyamides or aromatic polyamides. Examples of the aliphatic polyamide include nylon-6, nylon-6,6, and nylon such as a copolymer of nylon 6 and nylon 6,6. Examples of the aromatic polyamide include polymetaxylene adipamide ( MXD6). When the first plastic film 40 includes polyamide as a main component, the puncture strength of the laminate 30 including the first plastic film 40 can be increased.

  When the 1st plastic film 40 contains a polyamide as a main component, the thickness of the 1st plastic film 40 becomes like this. Preferably it is 12 micrometers or more, More preferably, it is 15 micrometers or more. Moreover, when the 1st plastic film 40 contains a polyamide as a main component, the thickness of the 1st plastic film 40 becomes like this. Preferably it is 25 micrometers or less, More preferably, it is 20 micrometers or less.

  The 1st plastic film 40 may be comprised by the single layer, and may be comprised by the some layer. When the first plastic film 40 includes a plurality of layers, the first plastic film 40 is a co-extruded film produced by co-extrusion, for example. The first plastic film 40 produced by coextrusion is, for example, a first layer made of polyester such as PET, a second layer made of polyamide such as nylon, and a third layer made of polyester such as PET, which are sequentially laminated. including. When the mass of the second layer made of polyamide such as nylon is 51% or more of the mass of the entire first plastic film 40, the main component of the first plastic film 40 produced by co-extrusion is polyamide. I can say that.

(First adhesive layer)
The first adhesive layer 45 includes an adhesive for bonding the first plastic film 40 and the second plastic film 50 by a dry laminating method. The adhesive which comprises the 1st adhesive bond layer 45 is produced | generated from the adhesive composition produced by mixing the 1st composition containing a main ingredient and a solvent, and the 2nd composition containing a hardening | curing agent and a solvent. Specifically, an adhesive contains the hardened | cured material produced | generated by the reaction of the main ingredient and solvent in an adhesive composition.

  Examples of the adhesive include polyurethane. Polyurethane is a cured product produced by a reaction between a polyol as a main agent and an isocyanate compound as a curing agent. Examples of polyurethane include polyether polyurethane and polyester polyurethane. The polyether polyurethane is a cured product produced by a reaction between a polyether polyol as a main agent and an isocyanate compound as a curing agent. Polyester polyurethane is a cured product produced by a reaction between a polyester polyol as a main agent and an isocyanate compound as a curing agent.

  As isocyanate compounds, aromatic isocyanate compounds such as tolylene diisocyanate (TDI), 4,4′-diphenylmethane diisocyanate (MDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), etc. Aliphatic isocyanate compounds, or adducts or multimers of the above-mentioned various isocyanate compounds can be used.

  The thickness of the 1st adhesive bond layer 45 becomes like this. Preferably it is 2 micrometers or more, More preferably, it is 3 micrometers or more. Moreover, the thickness of the 1st adhesive bond layer 45 becomes like this. Preferably it is 6 micrometers or less, More preferably, it is 5 micrometers or less.

(Second plastic film)
The second plastic film 50 is, for example, a plastic film that is stretched in a predetermined direction, like the first plastic film 40. Similar to the first plastic film 40, the second plastic film 50 also functions as a base material layer for giving the laminate 30 a predetermined strength. The extending direction of the second plastic film 50 is not particularly limited as in the case of the first plastic film 40.

  Similar to the first plastic film 40, the second plastic film 50 contains polyester or polyamide as a main component. In addition, in order to give the laminated body 30 heat resistance, it is preferable that at least one of the first plastic film 40 and the second plastic film 50 contains polyester as a main component. Therefore, when the first plastic film 40 includes polyamide as a main component, the second plastic film 50 includes polyester as a main component. When the 1st plastic film 40 contains polyester as a main component, the 2nd plastic film 50 may contain polyester as a main component, and may contain polyamide as a main component.

  When the second plastic film 50 contains polyester as a main component, for example, when it contains 51% by mass or more of polyester, examples of polyester include PET, PBT, etc., as in the case of the first plastic film 40. Can do. The thickness of the second plastic film 50 is preferably 9 μm or more, and more preferably 12 μm or more. Moreover, when the 2nd plastic film 50 contains polyester as a main component, the thickness of the 2nd plastic film 50 becomes like this. Preferably it is 25 micrometers or less, More preferably, it is 20 micrometers or less. When the second plastic film 50 contains polyester as a main component, the second plastic film 50 has the same thermal conductivity, melting point, and the like as those of the first plastic film 40 containing polyester as a main component.

  When the second plastic film 50 contains polyamide as a main component, for example, when it contains 51% by mass or more of polyamide, examples of polyamide are aliphatic polyamide or aromatic polyamide as in the case of the first plastic film 40. Can be mentioned. The thickness of the 2nd plastic film 50 becomes like this. Preferably it is 12 micrometers or more, More preferably, it is 15 micrometers or more. Moreover, when the 2nd plastic film 50 contains a polyamide as a main component, the thickness of the 2nd plastic film 50 becomes like this. Preferably it is 25 micrometers or less, More preferably, it is 20 micrometers or less.

(Second adhesive layer)
The second adhesive layer 55 includes an adhesive for bonding the second plastic film 50 and the sealant film 70 by a dry laminating method. As an example of the adhesive of the second adhesive layer 55, as in the case of the first adhesive layer 45, polyurethane or the like can be used. In addition to the configuration, materials, and characteristics described below, the configuration, material, and characteristics of the second adhesive layer 55 can be the same as those of the first adhesive layer 45.

  The thickness of the second adhesive layer 55 is preferably 2 μm or more, and more preferably 3 μm or more. The thickness of the second adhesive layer 55 is preferably 6 μm or less, more preferably 5 μm or less.

  By the way, as an isocyanate compound which comprises the hardening | curing agent of an adhesive agent, as mentioned above, an aromatic isocyanate compound and an aliphatic isocyanate compound exist. Among these, aromatic isocyanate compounds elute components that cannot be used in food applications under high-temperature environments such as heat sterilization. By the way, the second adhesive layer 55 is in contact with the sealant film 70. For this reason, when the 2nd adhesive bond layer 55 contains an aromatic isocyanate compound, the component eluted from the aromatic isocyanate compound adheres to the content accommodated in the accommodating part 17 which contact | connects the sealant film 70. FIG. There is.

  In consideration of such problems, preferably, a cured product produced by a reaction between a polyol as a main agent and an aliphatic isocyanate compound as a curing agent as an adhesive constituting the second adhesive layer 55. Is used. Thereby, it can prevent that the component which cannot be used for the food use resulting from the 2nd adhesive bond layer 55 adheres to the content.

(Sealant film)
Next, the sealant film 70 will be described. As a material constituting the sealant film 70, one or more resins selected from polyethylene such as low density polyethylene and linear low density polyethylene, and polypropylene can be used. The sealant film 70 may be a single layer or a multilayer. The sealant film 70 is preferably made of an unstretched film. “Unstretched” is a concept that includes not only a film that is not stretched at all, but also a film that is slightly stretched due to the tension applied during film formation.

  A sterilization process such as a boil process or a retort process is performed at a high temperature on the bag 10 formed of the laminate 30. Therefore, the sealant film 70 having heat resistance that can withstand the processing at these high temperatures is used.

  The melting point of the material constituting the sealant film 70 is preferably 150 ° C. or higher, and more preferably 160 ° C. or higher. By increasing the melting point of the sealant film 70, the bag 10 can be retorted at a high temperature, and therefore the time required for the retort processing can be shortened. The melting point of the material constituting the sealant film 70 is lower than the melting point of the resin constituting the plastic films 40 and 50.

  When considering from the viewpoint of retort processing, a material mainly composed of propylene can be used as a material constituting the sealant film 70. Here, the “material mainly composed of propylene” means a material having a propylene content of 90% by mass or more. Specific examples of the material mainly composed of propylene include propylene / ethylene block copolymer, propylene / ethylene random copolymer, polypropylene such as homopolypropylene, or a mixture of polypropylene and polyethylene. Can do. Here, the “propylene / ethylene block copolymer” means a material having a structural formula represented by the following formula (I). The “propylene / ethylene random copolymer” means a material having a structural formula represented by the following formula (II). “Homopolypropylene” means a material having the structural formula shown in the following formula (III).

  When a material containing propylene as a main component and a mixture of polypropylene and polyethylene is used, the material may have a sea-island structure. Here, the “sea-island structure” means a structure in which polyethylene is discontinuously dispersed in a region where polypropylene is continuous.

When considered from the viewpoint of boil processing, examples of the material constituting the sealant film 70 include polyethylene, polypropylene, or a combination thereof. Examples of polyethylene include medium density polyethylene, linear low density polyethylene, and combinations thereof. For example, it is also possible to use the materials mentioned as the material constituting the sealant film 70 from the viewpoint of the above retort processing. The material constituting the sealant film 70 has a melting point of, for example, 100 ° C. or higher, more preferably 105 ° C. or higher, and still more preferably 110 ° C. or higher. When polyethylene is used as the material constituting the sealant film 70, a melting point of 100 ° C. or higher can be realized, for example, when the density of polyethylene is 0.920 g / cm ³ or higher. Specific examples of the sealant film 70 having a melting point of 100 ° C. or higher include TUX-HC manufactured by Mitsui Chemicals Tosero, L6101 manufactured by Toyobo, and LS700C manufactured by Idemitsu Unitech. Specific examples of the sealant film 70 having a melting point of 105 ° C. or higher include NB-1 manufactured by Tamapoli. Specific examples of the sealant film 70 having a melting point of 110 ° C. or higher include LS760C manufactured by Idemitsu Unitech, TUX-HZ manufactured by Mitsui Chemicals Tosero, and the like.

  Preferably, the sealant film 70 is a single layer film containing a propylene / ethylene block copolymer. For example, the sealant film 70 is a single-layer unstretched film whose main component is a propylene / ethylene block copolymer. By using the propylene / ethylene block copolymer, the impact resistance of the sealant film 70 can be increased, and thereby the bag 10 can be prevented from being broken due to the impact at the time of dropping. Moreover, the puncture resistance of the laminated body 30 can be improved.

  Further, by using the propylene / ethylene block copolymer, the strength of the seal portion constituted by the sealant film 70 at a high temperature, for example, 100 ° C., that is, the above-mentioned hot seal strength is low, for example, 25 It becomes smaller than the sealing strength at the time of ° C., that is, the above-mentioned normal temperature sealing strength. Since the hot seal strength is low, when the bag 10 is heated using a microwave oven, the steam release seal portion 20a is easily peeled off, and the steam in the housing portion 17 is easily released to the outside of the bag 10. For this reason, it can suppress that the internal pressure of the accommodating part 17 becomes excessive, and it can suppress that the laminated body 30 is damaged by this by heating.

  The hot seal strength at 15 mm width at 100 ° C. of the seal portion of the bag 10 is preferably 23 N or less, more preferably 20 N or less, and further preferably 15 N or less. Further, the hot seal strength of the seal portion of the bag 10 may be 11 N or less or 10 N or less. In addition, when the hot seal strength is too low, it is considered that the steam vent seal portion 20a is peeled off before the contents are sufficiently heated and pressurized, and the pressure and temperature of the housing portion 17 are lowered. It is done. Considering this point, the hot seal strength of the seal portion of the bag 10 is preferably 4N or more, more preferably 5N or more.

  Moreover, the normal temperature seal strength in a 15 mm width at 25 ° C. of the seal portion of the bag 10 is preferably 60 N or less, more preferably 55 N or less, and may be 50 N or less. By forming the seal portion so that the normal temperature seal strength is 60 N or less, the hot seal strength of the seal portion can be 23 N or less. Moreover, the normal temperature seal strength in a 15 mm width at 25 ° C. of the seal portion of the bag 10 is preferably 35 N or more, more preferably 40 N or more, and may be 45 N or more, or 50 N or more. By forming the seal portion so that the normal temperature seal strength is 35 N or more, it is possible to prevent the seal portion of the bag 10 from being peeled off due to the force received by the bag 10 during transportation or the like. In addition, by forming the seal portion so that the normal temperature seal strength is 40 N or more, it is possible to suppress variations in the normal temperature seal strength due to variations in the seal temperature, as shown in examples described later. .

  The propylene / ethylene block copolymer includes, for example, a sea component made of polypropylene and an island component made of an ethylene / propylene copolymer rubber component. The sea component can contribute to enhancing the blocking resistance, heat resistance, rigidity, seal strength and the like of the propylene / ethylene block copolymer. In addition, the island component can contribute to enhancing the impact resistance of the propylene / ethylene block copolymer. Therefore, the mechanical properties of the sealant film 70 containing the propylene / ethylene block copolymer can be adjusted by adjusting the ratio of the sea component and the island component.

  In the propylene / ethylene block copolymer, the mass ratio of the sea component made of polypropylene is higher than the mass ratio of the island component made of the ethylene / propylene copolymer rubber component. For example, in the propylene / ethylene block copolymer, the mass ratio of the sea component made of polypropylene is at least 51% by mass, preferably 60% by mass or more, and more preferably 70% by mass or more.

  The single-layer sealant film 70 may further contain a second thermoplastic resin in addition to the first thermoplastic resin made of a propylene / ethylene block copolymer. Examples of the second thermoplastic resin include an α-olefin copolymer and polyethylene. The α-olefin copolymer is, for example, linear low density polyethylene. Examples of polyethylene include low density polyethylene, medium density polyethylene, and high density polyethylene. The second thermoplastic resin can contribute to improving the impact resistance of the sealant film 70.

The low-density polyethylene, density of 0.910 g / cm ³ or more and 0.925 g / cm ³ or less of polyethylene. Medium density polyethylene is polyethylene having a density of 0.926 g / cm ³ or more and 0.940 g / cm ³ or less. The high density polyethylene is polyethylene having a density of 0.941 g / cm ³ or more and 0.965 g / cm ³ or less. Low density polyethylene is obtained, for example, by polymerizing ethylene at a high pressure of 1000 atm or more and less than 2000 atm. The medium density polyethylene and the high density polyethylene are obtained, for example, by polymerizing ethylene at a medium pressure or low pressure of 1 atm or more and less than 1000 atm.

The medium density polyethylene and the high density polyethylene may partially contain a copolymer of ethylene and α-olefin. Even when ethylene is polymerized at medium or low pressure, medium density or low density polyethylene can be produced when a copolymer of ethylene and α-olefin is included. Such polyethylene is referred to as the above-mentioned linear low density polyethylene. Linear low density polyethylene is obtained by introducing a short chain branch by copolymerizing an α-olefin with a linear polymer obtained by polymerizing ethylene at medium or low pressure. Examples of the α-olefin include 1-butene (C ₄ ), 1-hexene (C ₆ ), 4-methylpentene (C ₆ ), 1-octene (C ₈ ) and the like. The density of the linear low density polyethylene is, for example, 0.915 g / cm ³ or more and 0.945 g / cm ³ or less.

  The α-olefin copolymer constituting the second thermoplastic resin of the propylene / ethylene block copolymer is not limited to the above-mentioned linear low density polyethylene. The α-olefin copolymer means a material having a structural formula represented by the following formula (IV).

R ₁ and R ₂ are both H (hydrogen atom) or an alkyl group such as CH ₃ or C ₂ H ₅ . J and k are both integers of 1 or more. J is larger than k. That is, in the α-olefin copolymer represented by the formula (IV), the left side structure including R ₁ is the base. R ₁ is, for example, H, and R ₂ is, for example, C ₂ H ₅ .

  In the sealant film 70, the mass ratio of the first thermoplastic resin made of the propylene / ethylene block copolymer is higher than the mass ratio of the second thermoplastic resin containing at least the α-olefin copolymer or polyethylene. For example, in the single-layer sealant film 70, the mass ratio of the first thermoplastic resin made of propylene / ethylene block copolymer is at least 51% by mass, preferably 60% by mass or more, and more preferably 70% by mass or more.

  As described above, the second thermoplastic resin can contribute to enhancing the impact resistance of the sealant film 70. Therefore, the mechanical properties of the sealant film 70 can be adjusted by adjusting the mass ratio of the second thermoplastic resin containing at least the α-olefin copolymer or polyethylene in the single-layer sealant film 70.

  The sealant film 70 may further contain a thermoplastic elastomer. By using a thermoplastic elastomer, the impact resistance and puncture resistance of the sealant film 70 can be further enhanced.

  The thermoplastic elastomer is, for example, a hydrogenated styrene thermoplastic elastomer. The hydrogenated styrene-based thermoplastic elastomer has a structure comprising a polymer block A mainly composed of at least one vinyl aromatic compound and a polymer block B mainly composed of at least one hydrogenated conjugated diene compound. . The thermoplastic elastomer may be an ethylene / α-olefin elastomer. The ethylene / α-olefin elastomer is a low crystalline or amorphous copolymer elastomer, and is a random copolymer of 50 to 90% by mass of ethylene as a main component and α-olefin as a copolymerization monomer. is there.

  The content of the propylene / ethylene block copolymer in the sealant film 70 is, for example, 80% by mass or more, and preferably 90% by mass or more.

  Examples of the method for producing a propylene / ethylene block copolymer include a method of polymerizing propylene, ethylene, and the like as raw materials using a catalyst. As the catalyst, Ziegler-Natta type or metallocene catalyst can be used.

  The thickness of the sealant film 70 is preferably 30 μm or more, more preferably 40 μm or more. Moreover, the thickness of the sealant film 70 is preferably 100 μm or less, and more preferably 80 μm or less.

Hereinafter, preferable mechanical properties of the single-layer sealant film 70 containing a propylene / ethylene block copolymer will be described.
The tensile elastic modulus (MPa) at 25 ° C. of the sealant film 70 in the flow direction (MD) is preferably 500 MPa or more, more preferably 600 MPa or more, and may be 650 MPa or more, or 700 MPa or more. Further, the product of the tensile modulus (MPa) of the sealant film 70 and the thickness (μm) of the sealant film 70 in the flow direction (MD) is preferably 35000 or more, more preferably 38000 or more, and further preferably 45000. That's it. Further, the tensile elastic modulus (MPa) at 25 ° C. of the sealant film 70 in the vertical direction (TD) is preferably 450 MPa or more, more preferably 500 MPa or more, and may be 550 MPa or more, or 600 MPa or more. . The product of the tensile modulus (MPa) of the sealant film 70 and the thickness (μm) of the sealant film 70 in the vertical direction (TD) is preferably 25000 or more, more preferably 30000 or more, and further preferably 35000. It is above and may be 38000 or more. When the sealant film 70 has a high tensile elastic modulus, the tearability when the bag 10 is opened can be improved.

  Further, the tensile elongation (%) at 25 ° C. of the sealant film 70 in the flow direction (MD) is preferably 1100 (%) or less, more preferably 1000 (%) or less, and 900 (%) or less. Or 800 (%) or less. The product of the tensile elongation (%) of the sealant film 70 and the thickness (μm) of the sealant film 70 in the flow direction (MD) is preferably 55000 or less, more preferably 50000 or less. Further, the tensile elongation (%) at 25 ° C. of the sealant film 70 in the vertical direction (TD) is preferably 1200 (%) or less, more preferably 1100 (%) or less, and 1000 (%) or less. Or 900 (%) or less. The product of the tensile elongation (%) of the sealant film 70 and the thickness (μm) of the sealant film 70 in the vertical direction (TD) is preferably 60000 or less, more preferably 55000 or less.

  The tensile modulus and tensile elongation can be measured according to JIS K7127. As a measuring device, a tensile tester RTC-1310A with a constant temperature bath manufactured by Orientec Co., Ltd. can be used. In the bag 10 shown in FIG. 1, the direction in which the upper portion 11 and the lower portion 12 extend is the flow direction of the film constituting the bag 10 such as the sealant film 70, and the direction in which the side portion 13 extends is the sealant film 70. Or the like, in the vertical direction of the film constituting the bag 10. Although not shown, the bag 10 may be configured such that the direction in which the upper portion 11 and the lower portion 12 extend is the vertical direction of the film, and the direction in which the side portion 13 extends is the flow direction of the film.

(Other layers)
The laminate 30 may further include a layer not shown in FIG. In the following, examples of further layers are described.

  The laminate 30 may further include a printing layer. The printed layer is a layer provided on the laminated body 30 in order to show product information or give aesthetics to the bag 10, and is printed on the first plastic film 40, for example. The print layer expresses letters, numbers, symbols, figures, patterns, and the like. As a material constituting the printing layer, gravure printing ink or flexographic printing ink can be used. As a specific example of the ink for gravure printing, FINAT manufactured by DIC Graphics Corporation can be given.

  Moreover, the laminated body 30 may further include a transparent gas barrier layer. The transparent gas barrier layer is formed on the surface of the plastic films 40 and 50 and includes at least a transparent vapor deposition layer made of an inorganic material having transparency. The transparent gas barrier layer may further include a transparent gas barrier coating film formed on the surface of the transparent vapor deposition layer and having transparency.

  The transparent vapor deposition layer functions as a layer having a gas barrier function that prevents permeation of oxygen gas and water vapor. Two or more transparent vapor deposition layers may be provided. When it has two or more transparent vapor deposition layers, each may have the same composition or different compositions. As a method for forming a transparent vapor deposition layer, for example, a physical vapor deposition method (Physical Vapor Deposition method, PVD method) such as a vacuum vapor deposition method, a sputtering method, and an ion plating method, a plasma chemical vapor deposition method, a heat Examples include chemical vapor deposition and chemical vapor deposition (chemical vapor deposition, CVD) such as photochemical vapor deposition. Specifically, a vapor deposition layer can be formed on a film formation roller using a roller-type vapor deposition film forming apparatus. Examples of the inorganic material constituting the transparent vapor deposition layer include aluminum oxide (aluminum oxide) and silicon oxide. The thickness of the transparent vapor deposition layer is preferably 40 mm or more and 130 mm or less, more preferably 50 mm or more and 120 mm or less.

The transparent gas barrier coating film is a layer that functions as a layer that suppresses permeation of oxygen gas, water vapor, and the like. The transparent gas barrier coating film 37 has a general formula R ¹ _n M (OR ² ) _m (wherein R ¹ and R ² represent an organic group having 1 to 8 carbon atoms, and M represents a metal atom). , N represents an integer of 0 or more, m represents an integer of 1 or more, and n + m represents a valence of M), and a polyvinyl alcohol as described above A transparent gas barrier composition containing a benzene-based resin and / or an ethylene / vinyl alcohol copolymer, and further polycondensed by a sol-gel method in the presence of a sol-gel method catalyst, acid, water, and an organic solvent. can get.

  In addition, as long as the normal temperature seal strength can be 60 N or less, the layer configuration of the stacked body 30 is not limited to the above-described one. For example, the laminate 30 may include only one plastic film.

Next, the layer structure of the lower film 16 will be described.

  As long as it has the inner surface which can be joined with the inner surface of the surface film 14 and the inner surface of the back surface film 15, the layer structure of the lower film 16 is arbitrary. For example, similar to the front film 14 and the back film 15, the above-described laminate 30 may be used as the lower film 16. Alternatively, a film having an inner surface constituted by a sealant layer and a configuration different from that of the laminate 30 may be used as the lower film 16.

Method for producing a laminate Next, an example of a method for producing a laminate 30.

  First, the first stretched plastic film 40 and the second stretched plastic film 50 described above are prepared. Subsequently, the first stretched plastic film 40 and the second stretched plastic film 50 are laminated via the first adhesive layer 45 by a dry laminating method. Thereafter, the laminate including the first stretched plastic film 40 and the second stretched plastic film 50 and the sealant film 70 are laminated via the second adhesive layer 55 by a dry laminating method. Thereby, the laminated body 30 provided with the 1st stretched plastic film 40, the 2nd stretched plastic film 50, and the sealant film 70 can be obtained.

  Alternatively, the second stretched plastic film 50 and the sealant film 70 are first laminated by the dry laminating method via the second adhesive layer 55, and then the first stretched plastic film 40, the second stretched plastic film 50, and the sealant film. The laminated body 30 may be manufactured by laminating the laminated body including 70 via the first adhesive layer 45 by a dry laminating method.

  In the dry laminating method, first, an adhesive composition is applied to one of two laminated films. Subsequently, the applied adhesive composition is dried to volatilize the solvent. Then, two films are laminated | stacked through the adhesive composition after drying. Subsequently, aging is performed for 24 hours or more in an environment of 20 ° C. or higher, for example, in a state where the two laminated films are wound up.

Method for producing a bag Next, a method for producing the bag 10 with the laminate 30 described above. First, the front film 14 and the back film 15 made of the laminate 30 are prepared. In addition, the lower film 16 in a folded state is inserted between the front film 14 and the back film 15. Subsequently, the inner surfaces of the films are heat-sealed at a predetermined sealing temperature to form seal portions such as the lower seal portion 12a, the side seal portion 13a, and the steam release seal portion 20a. The conditions of the heat seal process are set according to the material of the sealant film 70 so that the normal temperature seal strength of the seal portion is 60 N or less, and therefore the hot seal strength is 23 N or less.

  Subsequently, the films bonded to each other by heat sealing are cut into an appropriate shape to obtain a bag 10 shown in FIG. Subsequently, the contents 18 are filled into the bag 10 through the opening 11 b of the upper portion 11. The contents 18 are cooked foods containing moisture, such as curry, stew, and soup. The contents 18 may have a material containing a large amount of oil, such as meat and fish and seasonings for them. In addition to food, items that can be heated by hot water can be stored in the bag 10 as contents. Thereafter, the upper part 11 is heat-sealed to form an upper seal part. Thus, as shown in FIG. 4, the bag 10 in which the contents 18 are accommodated and sealed can be obtained. Thereafter, a sterilization process such as a boil process or a retort process is performed on the bag 10 containing the contents 18 as necessary.

  In FIG. 4, symbol H <b> 1 represents the distance in the second direction D <b> 2 from the upper seal portion 11 a to the center point C of the housing portion 17. Further, the symbol H2 represents the shortest distance from the steam release seal portion 20a to the center point C of the housing portion 17. In the type 1 bag as shown in FIG. 4, the ratio of the distance H2 to the distance H1 is, for example, 1.05 or more and 4.0 or less. By setting the distance H2 in this way, it is possible to prevent the upper seal portion 11a from being peeled before the steam release seal portion 20a when the bag 10 is heated. The center point C of the accommodating portion 17 is defined as the midpoint of a line segment connecting the midpoint Y1 of the inner edge of the upper seal portion 11a and the midpoint Y2 of the inner edge of the lower seal portion 12a.

Method of measuring the seal strength will be described method of measuring the seal strength of the seal portion of the bag 10. The seal strength can be measured according to JIS Z1707 7.5. As a measuring instrument, for example, a tensile tester RTC-1310A with a constant temperature bath manufactured by Orientec Co., Ltd. can be used.

  First, a test piece 90 for measuring the seal strength of the seal portion is prepared. For example, as shown by a dashed-dotted line frame denoted by reference numeral V in FIG. 4, a portion including the side seal portion 13a is cut out from the front film 14 and the back film 15 of the bag 10 along the first direction D1. A test piece 90 is obtained. The width W of the test piece 90 in the second direction D2 orthogonal to the first direction D1 is 15 mm.

  FIG. 5 is a cross-sectional view showing the test piece 90. The test piece 90 includes a seal portion 95 such as a side seal portion where the sealant film 70 of the front film 14 and the sealant film 70 of the back film 15 are joined, and the sealant film 70 and the back film 15 of the front film 14. And a non-seal portion 96 to which the sealant film 70 is not joined.

  FIG. 6 is a diagram showing how the seal strength is measured using the test piece 90. First, the front film 14 and the back film 15 are gripped by the gripping tool 91 and the gripping tool 92 of the measuring instrument in the non-sealing portion 96, respectively. Further, each of the grips 91 and 92 is pulled at a speed of 300 mm / min in directions opposite to each other in the direction perpendicular to the surface direction of the seal portion 95 of the test piece 90, and the maximum value of the tensile stress (see FIG. 7). Measure. FIG. 7 is a diagram showing changes in tensile stress with respect to the spacing S. FIG.

  About the some test piece 90, the maximum value of a tensile stress can be measured and the average value can be made into seal strength. The distance S between the grippers 91 and 92 when starting the pulling is, for example, 20, and the distance S between the grippers 91 and 92 when the pulling is finished is, for example, 40 mm. When measuring the above-mentioned normal temperature seal strength, the environment at the time of measurement is, for example, a temperature of 25 ° C. and a relative humidity of 50%. Moreover, when measuring the above-mentioned hot seal strength, the environment at the time of measurement is, for example, a temperature of 100 ° C. and a relative humidity of 50%.

Method for Measuring Peel Pressure Next, a method for measuring the peel pressure of the steam release seal portion 20a will be described with reference to FIG. FIG. 8 is a longitudinal sectional view showing the bag 10 in which the sensor 81 for measuring the peeling pressure is provided in the housing portion 17.

  First, as shown in FIG. 1 described above, a bag 10 in a partially opened state is prepared. Subsequently, a data logger sensor 81 capable of measuring pressure is provided inside the bag 10. For example, the sensor 81 is attached to the inner surface of the bag 10. Further, a predetermined amount of water, for example, 100 ml of water is filled in the storage portion 17 of the bag 10. Thereafter, a seal portion is formed in the opening of the bag 10 to seal the bag 10. As the data logger, for example, PICAVACQ PT made by TMI-ORION can be used. PicoVACQ PT can also measure temperature in addition to pressure.

  Subsequently, the water in the bag 10 is heated using a microwave oven or the like while measuring the pressure of the housing portion 17 at predetermined time intervals using the sensor 81. As a microwave oven, the arbitrary things in the range whose output is 500W-1500W can be used. The time interval is, for example, not less than 0.1 seconds and not more than 10 seconds, for example, 1.0 seconds.

  When water evaporates and the pressure in the accommodating portion 17 increases, the steam release seal portion 20a begins to peel off. When the peeling of the steam release seal portion 20a proceeds to the outer edge of the bag 10 and the accommodating portion 17 communicates with the non-sealed portion 20b and the outside of the bag 10, the pressure of the accommodating portion 17 measured by the sensor 81 rapidly decreases. To do. The pressure of the storage part 17 measured immediately before the pressure starts to drop rapidly is recorded as the peeling pressure of the steam release seal part 20a. The temperature of the housing part 17 immediately before the pressure starts to drop rapidly is, for example, 80 ° C. or more and 120 ° C. or less.

Heating method of the contents Next, an example of a method for heating the contents 18 contained in the bag 10.

  First, the bag 10 is placed inside the microwave oven in a state where the bag 10 is self-supporting with the lower portion 12 facing down. Next, the contents are heated using a microwave oven. As a result, the temperature of the contents 18 increases, and accordingly, the water contained in the contents 18 evaporates and the pressure in the accommodating portion 17 increases.

  When the pressure in the housing part 17 increases, the surface film 14 and the back film 15 bulge outward by the force received from the housing part 17. Here, in the present embodiment, the seal portion is configured so that the normal temperature seal strength is 60 N or less. Thereby, the bag 10 provided with the seal part which has a hot seal part of 23 N or less can be obtained. For this reason, before the temperature of the content 18 accommodated in the bag 10 becomes excessively high or the pressure of the content 18 becomes excessively high, the steam release seal portion 20a can be peeled off. . Accordingly, it is possible to suppress the formation of a hole in the laminated body 30 of the bag 10 or the formation of wrinkles in the laminated body 30 during heating.

  Note that various modifications can be made to the above-described embodiment. Hereinafter, modified examples will be described with reference to the drawings as necessary. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding parts in the above embodiment are used for the parts that can be configured in the same manner as in the above embodiment. A duplicate description is omitted. In addition, when it is clear that the operational effects obtained in the above-described embodiment can be obtained in the modified example, the description thereof may be omitted.

(First variation of bag)
In the steam release mechanism 20 of the present embodiment described above, the portion of the edge of the non-seal portion 20b that faces the opening 20p on the side edge in the first direction D1 is orthogonal to the first direction D1. The example extended in parallel with 2 directions D2 was shown. However, the present invention is not limited to this, and as shown in FIG. 9, the portion of the edge of the non-seal portion 20b that faces the opening 20p on the side edge in the first direction D1 is in the second direction D2. You may extend in the direction which inclines with respect. In the following description, the portion of the edge portion of the non-seal portion 20b that faces the side edge opening 20p in the first direction D1 is also referred to as a first edge portion 20b1. Of the edge of the non-seal part 20b, the part connected to the lower end of the first edge 20b1 via the connecting part 20b3 and extending toward the side edge of the bag 10 is also referred to as the second edge 20b2. Called.

  In the example shown in FIG. 9, the first edge 20b1 extends in a direction inclined with respect to the second direction D2 so as to be displaced toward the opening 20p side of the side edge toward the upper portion 11 side. Thereby, the vapor | steam which flowed into the non-seal part 20b through the position of the connection part 20b3 from the accommodating part 17 can be guide | induced smoothly to the opening part 20p. The angle θ1 formed by the direction in which the first edge portion 20b1 extends and the second direction D2 is, for example, 1 degree or more, preferably 10 degrees or more, or 20 degrees or more, and more preferably 30 degrees or more. Further, an angle θ1 formed by the direction in which the first edge portion 20b1 extends and the second direction D2 is, for example, 70 degrees or less, and may be 60 degrees or less. In the following description, the bag 10 in which the first edge portion 20b1 extends in the direction inclined with respect to the second direction D2 is also referred to as a type 1 (inclined) bag.

  In the example shown in FIG. 9, reference numeral 20a1 denotes an inner edge of a portion corresponding to the first edge portion 20b1 of the non-seal portion 20b in the steam release seal portion 20a, and is also referred to as a first inner edge in the following description. Reference numeral 20a2 denotes an inner edge of a portion corresponding to the second edge portion 20b2 of the non-seal portion 20b in the steam release seal portion 20a, and is also referred to as a second inner edge in the following description. Reference numeral 20a1 is a connecting portion 20a3 to which the first inner edge 20a1 and the second inner edge 20a2 are connected.

  In the example shown in FIG. 9, the angle θ2 formed by the direction in which the first inner edge 20a1 extends and the direction in which the second inner edge 20a2 extends is less than 90 degrees. Thereby, when the pressure of the accommodating part 17 increases, it will become easy to apply force to the connection part 20a3. This facilitates the peeling of the steam release seal portion 20a from the connection portion 20a3 to the position of the connection portion 20b3 of the non-seal portion 20b. The angle θ2 formed by the direction in which the first inner edge 20a1 extends and the direction in which the second inner edge 20a2 extends is preferably 89 degrees or less, more preferably 80 degrees or less or 70 degrees or less.

(Second modification of bag)
In the steam venting mechanism 20 of the present embodiment and the first modification described above, the non-seal portion 20b isolated from the housing portion 17 by the steam vent seal portion 20a extends to reach the outer edge of the bag 10. An example is shown. However, the present invention is not limited to this, and as shown in FIG. 10, the non-seal portion 20b may be surrounded by the steam release seal portion 20a and the side seal portion 13a. In this case, a through-hole 20c that penetrates at least one of the front film 14 or the back film 15 is formed in the non-seal portion 20b. In this case, the steam that has flowed into the non-seal portion 20b from the housing portion 17 through the peeled portion of the steam release seal portion 20a passes through the through hole 20c and escapes to the outside of the bag 10. In the following description, a bag of the type in which the non-seal part 20b of the steam release mechanism 20 is surrounded by the steam release seal part 20a and the side seal part 13a as shown in FIG. Also called.

  In the bag 10 shown in FIG. 10, the non-seal part 20b is located in the accommodating part 17 side rather than the side part seal part 13a. For this reason, when the width of the non-seal portion 20b in the first direction D1 is the same, the distance H2 from the steam release seal portion 20a of the bag 10 of type 2 of this modification to the center point C is as shown in FIGS. The distance H2 from the steam release seal portion 20a of the type 1 bag 10 to the center point C is shorter than the distance H2. For this reason, when the contents of the bag 10 are heated using a microwave oven or the like, a force is easily applied to the vapor vent seal portion 20a, and the peeling pressure of the vapor vent seal portion 20a tends to be low. In the type 2 bag as shown in FIG. 10, the ratio of the distance H2 to the distance H1 is, for example, 1.05 or more and 5.0 or less.

  Also in this modification, the seal portion is configured so that the normal temperature seal strength is 60 N or less. Thereby, the bag 10 provided with the seal part which has a hot seal part of 23 N or less can be obtained. For this reason, before the temperature of the content 18 accommodated in the bag 10 becomes excessively high or the pressure of the content 18 becomes excessively high, the steam release seal portion 20a can be peeled off. . Accordingly, it is possible to suppress the formation of a hole in the laminated body 30 of the bag 10 or the formation of wrinkles in the laminated body 30 during heating.

(Third modification of bag)
In the steam venting mechanism 20 according to the present embodiment and the first modification described above, the steam vent seal portion 20a is connected to the side seal portion 13a. However, the present invention is not limited to this, and as shown in FIG. 11, the steam release seal portion 20a may be separated from the side seal portion 13a. In this case, a through-hole 20c penetrating at least one of the front film 14 or the back film 15 is formed in the non-seal part 20b surrounded by the steam release seal part 20a. Similarly to the case of the first modification, the steam that has flowed into the non-seal portion 20b from the housing portion 17 through the peeled portion of the steam release seal portion 20a passes through the through hole 20c and escapes to the outside of the bag 10. In the following description, the type of bag in which the steam release seal portion 20a of the steam release mechanism 20 is spaced from the side seal portion 13a as shown in FIG. 11 is also referred to as a type 3 bag.

  In the bag 10 shown in FIG. 11, the non-seal portion 20b is separated from the side seal portion 13a. For this reason, when the width of the non-seal portion 20b in the first direction D1 is the same, the distance H2 from the steam release seal portion 20a of the bag 10 of type 3 of this modification to the center point C is the type shown in FIG. It is shorter than the distance H2 from the steam release seal portion 20a of the second bag 10 to the center point C. For this reason, when the contents of the bag 10 are heated using a microwave oven or the like, a force is more likely to be applied to the steam release seal portion 20a, and the peeling pressure of the steam release seal portion 20a is likely to be lower. In the type 3 bag as shown in FIG. 11, the ratio of the distance H2 to the distance H1 is, for example, not less than 1.05 and not more than 6.0.

  Also in this modification, the seal portion is configured so that the normal temperature seal strength is 60 N or less. Thereby, the bag 10 provided with the seal part which has a hot seal part of 23 N or less can be obtained. For this reason, before the temperature of the content 18 accommodated in the bag 10 becomes excessively high or the pressure of the content 18 becomes excessively high, the steam release seal portion 20a can be peeled off. . Accordingly, it is possible to suppress the formation of a hole in the laminated body 30 of the bag 10 or the formation of wrinkles in the laminated body 30 during heating.

  Note that when the distance H2 from the steam vent seal portion 20a to the center point C is shortened, a force is easily applied to the steam vent seal portion 20a other than when the contents of the bag 10 are heated using a microwave oven or the like. For example, when transporting the bag 10 in a state where a plurality of bags 10 are stacked, a force is easily applied to the steam release seal portion 20a, and unintentional release of the steam release seal portion 20a is likely to occur. In other words, the shorter the distance H2 from the steam release seal portion 20a to the center point C, the lower the load resistance of the bag 10. Therefore, in view of the load resistance of the bag 10, the type 2 bag 10 is preferable to the type 3 bag 10, and the type 1 bag 10 is more preferable.

(Fourth modification of bag)
FIG. 12 is a front view showing a modified example of the bag 10. As shown in FIG. 12, the surface film 14 may include a palm portion 14a in which the inner surfaces of the surface film 14 are partially overlapped. The palm portion 14a can be configured, for example, by folding back with a folding portion 14f so as to form a pleat on one surface film 14. Further, the palm portion 14a may be configured by overlapping a part of the two surface films 14.

  In the palm portion 14a, a palm seal portion 14b extending from one side seal portion 13a to the other side seal portion 13a is formed. In this case, the steam release mechanism 20 includes, for example, a steam release seal part 20a that protrudes from the palm seal part 14b toward the housing part 17, and a non-seal part 20b that is surrounded by the steam release seal part 20a and the joint seal part 14b. And a through hole 20c formed in the surface film 14 in the non-seal portion 20b.

  Also in this modification, when the pressure of the accommodating part 17 increases, the steam release seal part 20a peels and the accommodating part 17 and the non-seal part 20b communicate. The steam that has flowed into the non-seal portion 20b from the housing portion 17 through the peeled portion of the steam release seal portion 20a passes through the through hole 20c and escapes to the outside of the bag 10. In the following description, a bag of the type in which the steam release mechanism 20 is provided in the palm portion 14a as shown in FIG. In the type 4 bag as shown in FIG. 12, the ratio of the distance H2 to the distance H1 is, for example, 1.10 or more and 6.0 or less.

  Also in this modification, the seal portion is configured so that the normal temperature seal strength is 60 N or less. Thereby, the bag 10 provided with the seal part which has a hot seal part of 23 N or less can be obtained. For this reason, before the temperature of the content 18 accommodated in the bag 10 becomes excessively high or the pressure of the content 18 becomes excessively high, the steam release seal portion 20a can be peeled off. . Accordingly, it is possible to suppress the formation of a hole in the laminated body 30 of the bag 10 or the formation of wrinkles in the laminated body 30 during heating.

  EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited to description of a following example, unless the summary is exceeded.

(Example A1)
A stretched PET film having a thickness of 12 μm was prepared as the first plastic film 40. In addition, a stretched PET film having a thickness of 12 μm was prepared as the second plastic film 50. Further, as the sealant film 70, an unstretched polypropylene film ZK207 manufactured by Toray Film Processing Co., Ltd. was prepared. ZK207 contains the above-mentioned propylene / ethylene block copolymer. The thickness of the sealant film 70 was 70 μm.

  ZK207 has a high tensile elastic modulus. Specifically, the tensile modulus of elasticity of ZK207 in the flow direction (MD) is 780 MPa when the thickness is 50 μm and 680 MPa when the thickness is 60 μm. Further, the tensile modulus of elasticity of ZK207 in the vertical direction (TD) is 630 MPa when the thickness is 50 μm and 560 MPa when the thickness is 60 μm. Therefore, the product of the tensile modulus (MPa) and the thickness (μm) of ZK207 in the flow direction is 39000 when the thickness is 50 μm and 40800 when the thickness is 60 μm. The product of the tensile modulus (MPa) and thickness (μm) of ZK207 in the vertical direction is 31500 when the thickness is 50 μm and 33600 when the thickness is 60 μm.

  ZK207 has a low tensile elongation. Specifically, the tensile elongation of ZK207 in the flow direction (MD) is 790% when the thickness is 50 μm and 730% when the thickness is 60 μm. The tensile elongation of ZK207 in the vertical direction (TD) is 1020% when the thickness is 50 μm, and 870% when the thickness is 60 μm. Therefore, the product of the tensile elongation (%) and thickness (μm) of ZK207 in the flow direction is 39500 when the thickness is 50 μm and 43800 when the thickness is 60 μm. The product of the tensile elongation (%) and the thickness (μm) of ZK207 in the vertical direction is 51000 when the thickness is 50 μm and 52200 when the thickness is 60 μm.

  Then, the 1st plastic film 40, the 2nd plastic film 50, and the sealant film 70 were laminated | stacked by the dry lamination method, and the laminated body 30 was produced. As the first adhesive layer 45 and the second adhesive layer 55, a two-component polyurethane adhesive (main agent: RU-40, curing agent: H-4) manufactured by Rock Paint Co., Ltd. was used. In addition, RU-40 of the main ingredient is a polyester polyol. The thickness of the 1st adhesive bond layer 45 and the 2nd adhesive bond layer 55 was 3.5 micrometers.

  Subsequently, the inner surfaces 30x of the two laminates 30 were partially heat sealed to form a seal portion. The temperature during the heat sealing process (hereinafter also referred to as the sealing temperature) was 170 ° C. Subsequently, a portion including the seal portion of the two laminates 30 was cut out, and the above-described test piece 90 for measuring the seal strength was produced. Thereafter, the normal temperature seal strength of the laminate 30 was measured in an environment of a temperature of 25 ° C. and a relative humidity of 50% in accordance with JIS 1707 7.5. As a measuring device, a tensile tester RTC-1310A with a constant temperature bath manufactured by Orientec Co., Ltd. was used.

  In this example, heat for simulating treatment such as retort treatment and boil treatment was not applied to the test piece 90 before measuring the seal strength. In the following description, the state of the laminated body 30 and the test piece 90 to which heat that simulates processing such as retort processing and boil processing is not applied is also referred to as before retort processing.

  Moreover, the test piece 90 produced with different sealing temperature was prepared, and normal temperature sealing intensity | strength was measured, respectively. Here, a test piece 90 having different sealing temperatures from 175 ° C. to 220 ° C. in increments of 5 ° C. was prepared. The results are shown in the row of “room temperature seal strength (before retort treatment)” in FIG. FIG. 14 shows a graph obtained by plotting the seal strength against the seal temperature.

(Example A2)
The room temperature seal strength of the test piece 90 was measured in the same manner as in Example A1 except that the test piece 90 was produced using the laminate 30 to which heat that simulated retort treatment was applied. The results are shown in the row of “room temperature seal strength (after retort treatment)” in FIG. FIG. 14 shows a graph obtained by plotting the seal strength against the seal temperature.

The treatment applied to the laminate 30 constituting the test piece 90 is as follows.
・ Heating temperature: 121 ° C
・ Heating time: 40 minutes ・ Pressure: 0.2 MPa

(Example A3)
The hot seal strength of the test piece 90 was measured in the same manner as in Example A1, except that the seal strength was measured under an environment of a temperature of 100 ° C. and a relative humidity of 50%. The results are shown in the row of “Hot seal strength (before retort treatment)” in FIG. FIG. 14 shows a graph obtained by plotting the seal strength against the seal temperature.

(Example A4)
The hot seal strength of the test piece 90 was measured in the same manner as in Example A2 except that the test piece 90 was produced using the laminate 30 to which heat that simulated retort treatment was applied. The results are shown in the row of “Hot seal strength (after retort treatment)” in FIG. FIG. 14 shows a graph obtained by plotting the seal strength against the seal temperature.

  As shown in FIGS. 13 and 14, there was a tendency that the normal temperature seal strength increased as the seal temperature increased. In particular, when the normal temperature seal strength after retorting was less than 40 N, the dependency of the normal temperature seal strength on the seal temperature was large. Therefore, from the viewpoint of stability of the normal temperature seal strength, the normal temperature seal strength after the retort treatment is preferably 40 N or more, more preferably 45 N or more, and even more preferably 50 N or more. Thereby, it can suppress that the normal temperature seal | sticker intensity | strength after a retort process varies due to the dispersion | variation in seal temperature.

  As in the case of the normal temperature seal strength, the hot seal strength tended to increase as the seal temperature increased.

  As shown in FIGS. 13 and 14, the room temperature seal strength of the test piece 90 after the retort treatment tended to be smaller than the room temperature seal strength of the test piece 90 before the retort treatment. The difference between the normal temperature seal strength of the test piece 90 after the retort treatment and the normal temperature seal strength of the test piece 90 before the retort treatment was in the range of 5N to 13N. On the other hand, the difference between the hot seal strength of the test piece 90 after the retort treatment and the hot seal strength of the test piece 90 before the retort treatment was smaller than that of the normal temperature seal strength and was 3N or less.

(Example B1)
A stretched PET film having a thickness of 12 μm was prepared as the first plastic film 40. In addition, a stretched PET film having a thickness of 12 μm was prepared as the second plastic film 50. Further, as the sealant film 70, an unstretched polypropylene film ZK207 manufactured by Toray Film Processing Co., Ltd. was prepared. ZK207 contains the above-mentioned propylene / ethylene block copolymer. The thickness of the sealant film 70 was 70 μm.

  Then, the 1st plastic film 40, the 2nd plastic film 50, and the sealant film 70 were laminated | stacked by the dry lamination method, and the laminated body 30 was produced. As the first adhesive layer 45 and the second adhesive layer 55, a two-component polyurethane adhesive (main agent: RU-40, curing agent: H-4) manufactured by Rock Paint Co., Ltd. was used. In addition, RU-40 of the main ingredient is a polyester polyol. The thickness of the 1st adhesive bond layer 45 and the 2nd adhesive bond layer 55 was 3.5 micrometers.

[Evaluation of seal strength]
Subsequently, the inner surfaces 30x of the two laminates 30 were heat-sealed at the first sealing temperature to form a seal portion. Then, the test piece 90 for measuring the seal | sticker intensity | strength by cutting out the part containing a seal | sticker part among the two laminated bodies 30 was produced. Here, a plurality of test pieces 90 before retorting treatment as in Example A1 and a plurality of test pieces 90 after retorting treatment as in Example A2 were prepared. Subsequently, the normal temperature seal strength and the hot seal strength were measured using the test piece 90 before the retort treatment. As a result, the normal temperature seal strength and the hot seal strength were 65 N and 23 N, respectively. Moreover, the normal temperature seal strength and the hot seal strength were measured using the test piece 90 after the retort treatment. As a result, the normal temperature seal strength and the hot seal strength were 60 N and 23 N, respectively.

[Evaluation of peeling pressure]
Then, the bag 10 provided with the type 1 steam release mechanism 20 shown in FIG.1 and FIG.4 using the laminated body 30 was produced. The height S1 of the bag 10 was 145 mm, and the width S2 was 140 mm. Further, the height S3 of the folded lower film 16, that is, the height from the lower end portion of the bag 10 to the folded portion 16f was 40 mm. In the following description, the bag 10 having a height S1 of 145 mm, a width S2 of 140 mm, and a height S3 of 40 mm is also referred to as an S-size bag 10. Subsequently, 100 ml of water was filled into the bag 10, and a data logger sensor 81 was placed inside the bag 10, and the upper portion 11 of the bag 10 was heat sealed to form an upper seal portion 11 a.

  Then, the water in the bag 10 was heated using the microwave oven of output 500W, measuring the pressure of the accommodating part 17 every second using the sensor 81. FIG. As a microwave oven with an output of 500 W, NE-MS261 manufactured by Panasonic was used. When the pressure of the storage part 17 increases and the peeling of the steam release seal part 20a reaches the outer edge of the bag 10, the steam in the storage part 17 begins to be discharged to the outside of the bag 10, and the pressure of the storage part 17 rapidly decreases. . The peeling pressure, which is the pressure in the housing portion 17 immediately before the pressure starts to drop rapidly, was 130.7 kPa.

[Evaluation of heat resistance]
Similarly to the evaluation of the peeling pressure, an S size bag 10 was produced using the laminate 30. Subsequently, 100 g of a content containing a large amount of oil was filled into the S-size bag 10, and the upper part 11 was heat-sealed to form the upper seal part 11a.

  Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. The test was performed on 10 bags 10. As a result, it was confirmed that the laminated body 30 did not have a hole in 7 of 10 bags 10.

(Example B2)
Type 1 bag 10 was produced using the same laminate 30 as in Example B1. The height S1 of the bag 10 was 145 mm, the width S2 was 150 mm, and the height S3 of the folded lower film 16 was 43 mm. In the following description, the bag 10 having a height S1 of 145 mm, a width S2 of 150 mm, and a height S3 of 43 mm is also referred to as an M size bag 10.

  Subsequently, as in Example B1, 100 ml of water was filled into the bag 10, and the upper part 11 was heat-sealed to form an upper seal part. Thereafter, as in the case of Example B1, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 132.5 kPa.

  Further, similarly to Example B1, 100 g of a content containing a large amount of oil was filled into the inside of the M-size bag 10, and the upper part 11 was heat-sealed to form the upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Example B3)
Using the same laminate 30 as in Example B1, an S size type 10 (inclined) bag 10 shown in FIG. 9 was produced. The angle θ1 formed by the direction in which the first edge 20b1 extends and the second direction D2 was 30 degrees. The angle θ2 formed by the direction in which the first inner edge 20a1 extends and the direction in which the second inner edge 20a2 extends was 70 degrees.

  Subsequently, as in Example B1, 100 ml of water was filled into the bag 10, and the upper part 11 was heat-sealed to form an upper seal part. Thereafter, as in the case of Example B1, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 129.4 kPa.

  Further, similarly to Example B1, 100 g of a content containing a large amount of oil was filled into the S-sized bag 10, and the upper part 11 was heat-sealed to form the upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Example B4)
Seal strength was measured using a test piece 90 produced by heat-sealing the same laminate 30 as in Example B1 at a second seal temperature lower than the first seal temperature described above. In the test piece 90 before the retort treatment, the normal temperature seal strength and the hot seal strength were 60 N and 15 N, respectively. Moreover, in the test piece 90 after the retort treatment, the normal temperature seal strength and the hot seal strength were 55N and 15N, respectively.

  In addition, an S size type 1 bag 10 was produced in the same manner as in Example B1 except that the sealing temperature was the second sealing temperature described above. Thereafter, as in the case of Example B1, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 127.3 kPa.

  Further, 100 g of a content containing a large amount of oil is filled into the inside of the S-size type 1 bag 10 in the same manner as in Example B1, except that the sealing temperature is the second sealing temperature described above. The upper part 11 was heat-sealed to form an upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Example B5)
Using the test piece 90 produced by heat-sealing the same laminate 30 as in Example B1 at a third seal temperature lower than the second seal temperature in Example 4, the seal strength was increased. It was measured. In the test piece 90 before the retort treatment, the normal temperature seal strength and the hot seal strength were 55 N and 10 N, respectively. Moreover, in the test piece 90 after the retort treatment, the normal temperature seal strength and the hot seal strength were 45 N and 9 N, respectively.

  Further, an S size type 1 bag 10 was produced in the same manner as in Example B1 except that the seal temperature was the above-described third seal temperature. Thereafter, as in the case of Example B1, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 124.9 kPa.

  Further, 100 g of a content containing a large amount of oil was filled into the inside of the S-size type 1 bag 10 in the same manner as in Example B1, except that the seal temperature was the third seal temperature described above. The upper part 11 was heat-sealed to form an upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Example B6)
An M size type 1 bag 10 was produced in the same manner as in Example B2, except that the temperature of the heat sealing treatment was set to the third sealing temperature as in Example B5. Thereafter, as in the case of Example B1, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 125.5 kPa.

  Further, as in the case of Example B2, except that the temperature of the heat sealing process was set to the third sealing temperature as in Example B5, 100 g of the content containing a large amount of oil was added to the M size bag. 10 was filled, and the upper part 11 was heat-sealed to form an upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Example B7)
The same laminated body 30 as in Example B5 was heat-sealed at the above-described third sealing temperature, thereby producing an M size type 1 bag 10 similar to that in Example B6. Subsequently, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 1600 W, and the peeling pressure was measured. A NE-1801 manufactured by Panasonic was used as the microwave oven with an output of 1600 W. As a result, the peeling pressure was 124.8 kPa.

  Further, the same laminate 30 as in Example B5 was heat-sealed at the above-described third sealing temperature, thereby producing an M size type 1 bag 10 similar to that in Example B6. Subsequently, 100 g of a content containing a large amount of oil was filled into the inside of the M size type 1 bag 10, and the upper part 11 was heat-sealed to form the upper seal part 11a. Thereafter, the water in the bag 10 was heated for 40 seconds using a microwave oven with an output of 1600 W, and it was confirmed whether or not the laminate 30 constituting the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Example B8)
A stretched PET film having a thickness of 12 μm was prepared as the first plastic film 40. In addition, a stretched nylon film having a thickness of 15 μm was prepared as the second plastic film 50. Further, as the sealant film 70, an unstretched polypropylene film ZK207 manufactured by Toray Film Processing Co., Ltd. was prepared. The thickness of the sealant film 70 was 70 μm.

  Subsequently, using the test piece 90 produced by partially heat-sealing the inner surfaces 30x of the two laminated bodies 30 at the fourth sealing temperature, the laminated body 30 in the same manner as in Example B1. The sealing strength between them was measured. In the test piece 90 before the retort treatment, the normal temperature seal strength and the hot seal strength were 58N and 11N, respectively. Moreover, in the test piece 90 after the retort treatment, the normal temperature seal strength and the hot seal strength were 50 N and 11 N, respectively.

  In addition, an S size type 1 bag 10 was produced using the laminate 30 at the fourth sealing temperature. Thereafter, as in the case of Example B1, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 125.9 kPa.

  In addition, an S-size bag 10 was produced at the fourth seal temperature using the laminate 30. Subsequently, 100 g of a content containing a large amount of oil was filled into the bag 10, and the upper part 11 was heat-sealed to form an upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 40 seconds using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Example B9)
Seal strength was measured using a test piece 90 produced by heat-sealing the same laminate 30 as in Example B8 at a fifth seal temperature lower than the fourth seal temperature described above. In the test piece 90 before the retort treatment, the normal temperature seal strength and the hot seal strength were 55 N and 10 N, respectively. Moreover, in the test piece 90 after the retort treatment, the normal temperature seal strength and the hot seal strength were 45 N and 9 N, respectively.

  Further, an S size type 1 bag 10 was produced in the same manner as in Example B8, except that the seal temperature was the above-described fifth seal temperature. Thereafter, as in Example B8, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 122.2 kPa.

  Further, 100 g of a content containing a large amount of oil is filled into the inside of the S size type 1 bag 10 in the same manner as in Example B8, except that the seal temperature is the fifth seal temperature described above. The upper part 11 was heat-sealed to form an upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Example B10)
Seal strength was measured using a test piece 90 produced by heat-sealing the same laminate 30 as in Example B8 at a sixth sealing temperature lower than the fifth sealing temperature described above. In the test piece 90 before the retort treatment, the normal temperature seal strength and the hot seal strength were 50 N and 7 N, respectively. Moreover, in the test piece 90 after the retort treatment, the normal temperature seal strength and the hot seal strength were 38N and 7N, respectively.

  Further, an S size type 1 bag 10 was produced in the same manner as in Example B8, except that the sealing temperature was the above-described sixth sealing temperature. Thereafter, as in Example B8, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 120.2 kPa.

  Further, 100 g of a content containing a large amount of oil was filled into the inside of the S-size type 1 bag 10 in the same manner as in Example B8, except that the seal temperature was the above-described sixth seal temperature. The upper part 11 was heat-sealed to form an upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Example B11)
Seal strength was measured using a test piece 90 produced by heat-sealing the same laminate 30 as in Example B8 at a seventh sealing temperature lower than the sixth sealing temperature described above. In the test piece 90 before the retort treatment, the normal temperature seal strength and the hot seal strength were 45 N and 6 N, respectively. Moreover, in the test piece 90 after the retort treatment, the normal temperature seal strength and the hot seal strength were 32N and 6N, respectively.

  Further, an S size type 1 bag 10 was produced in the same manner as in Example B8, except that the seal temperature was the seventh seal temperature described above. Thereafter, as in Example B8, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 118.9 kPa.

  Also, 100 g of the content containing a large amount of oil was filled into the inside of the S size type 1 bag 10 in the same manner as in Example B8, except that the seal temperature was the seventh seal temperature described above. The upper part 11 was heat-sealed to form an upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Comparative Example B1)
Seal strength was measured using a test piece 90 produced by heat-sealing the same laminate 30 as in Example B1 at an eighth seal temperature higher than the first seal temperature described above. In the test piece 90 before the retort treatment, the normal temperature seal strength and the hot seal strength were 70 N and 26 N, respectively. Moreover, in the test piece 90 after the retort treatment, the normal temperature seal strength and the hot seal strength were 65 N and 26 N, respectively.

  Further, an S size type 1 bag 10 was produced in the same manner as in Example B1 except that the sealing temperature was the above-described eighth sealing temperature. Thereafter, as in the case of Example B1, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 133.2 kPa.

  Further, 100 g of a content containing a large amount of oil was filled into the inside of the S-size type 1 bag 10 in the same manner as in Example B1, except that the seal temperature was the third seal temperature described above. The upper part 11 was heat-sealed to form an upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that the laminated body 30 had holes in 6 of 10 bags 10.

(Comparative Example B2)
Seal strength was measured using a test piece 90 produced by heat-sealing the same laminate 30 as in Example B8 at a ninth sealing temperature lower than the seventh sealing temperature described above. In the test piece 90 before the retort treatment, the normal temperature seal strength and the hot seal strength were 35 N and 5 N, respectively. Moreover, in the test piece 90 after the retort treatment, the normal temperature seal strength and the hot seal strength were 25 N and 5 N, respectively.

  Further, an S size type 1 bag 10 was produced in the same manner as in Example B8 except that the seal temperature was the ninth seal temperature described above. Thereafter, as in the case of Example B7, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 1600 W, and the peeling pressure was measured. As a result, the peeling pressure was 115.4 kPa.

  Also, 100 g of the content containing a large amount of oil was filled into the S size type 1 bag 10 in the same manner as in Example B8, except that the seal temperature was the ninth seal temperature described above. The upper part 11 was heat-sealed to form an upper seal part 11a. Thereafter, the bag 10 containing the contents was heated for 40 seconds using a microwave oven with an output of 1600 W, and it was confirmed whether or not the laminate 30 constituting the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Example B12)
Using the same laminate 30 as in Example B1, an S size type 2 bag 10 was produced. Subsequently, as in Example B1, 100 ml of water was filled into the bag 10, and the upper part 11 was heat-sealed to form an upper seal part. Thereafter, as in the case of Example B1, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 124.2 kPa.

  Similarly to the evaluation of the peeling pressure, an S size type 2 bag 10 was produced using the laminate 30. Subsequently, 100 g of a content containing a large amount of oil was filled into the bag 10, and the upper part 11 was heat-sealed to form an upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

(Example B13)
Using the same laminate 30 as in Example B1, an S size type 3 bag 10 was produced. Subsequently, as in Example B1, 100 ml of water was filled into the bag 10, and the upper part 11 was heat-sealed to form an upper seal part. Thereafter, as in the case of Example B1, while measuring the pressure in the container 17 using the sensor 81, the water in the bag 10 was heated using a microwave oven with an output of 500 W, and the peeling pressure was measured. As a result, the peeling pressure was 122.1 kPa.

  Similarly to the evaluation of the peeling pressure, an S size type 3 bag 10 was produced using the laminate 30. Subsequently, 100 g of a content containing a large amount of oil was filled into the bag 10, and the upper part 11 was heat-sealed to form an upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the laminated body 30 which comprises the bag 10 was damaged. As a result, it was confirmed that there were no holes in the laminate 30 in 10 of 10 bags 10.

  The layer structures of the laminates of Examples B1 to B13 and Comparative Examples B1 to B2, the measurement results of seal strength, the measurement results of peeling pressure, the evaluation results of heat resistance, and the like are collectively shown in FIG. In FIG. 15, in the “layer configuration” column, the components of the laminated body are described from the top in order from the outer layer. Moreover, in the column of “heat resistance”, in 10 of 10 bags 10, when there is no hole in the laminated body 30, “great” is described, and in 5 to 9 of 10 bags 10 When there was no hole in the laminated body 30, “good” was written, and in 6 or more of the bags 10, when the laminated body 30 had a hole, “bad” was written.

  As can be seen from the comparison between Examples B1 to B13 and Comparative Example B1, the hot seal strength of the seal portion after the retort treatment is obtained by configuring the seal portion so that the normal temperature seal strength after the retort treatment is 60 N or less. Can be made 23 N or less, and the peeling pressure can be made 133 kPa or less. Further, by configuring the seal portion so that the normal temperature seal strength after retort treatment is 55 N or less, the hot seal strength of the seal portion after retort treatment can be 15 N or less, and the peeling pressure is 130 kPa. I was able to: Further, by configuring the seal portion so that the normal temperature seal strength after retort treatment is 50 N or less, the hot seal strength of the seal portion after retort treatment can be 11 N or less, and the peeling pressure is 126 kPa. I was able to: Thus, by setting the formation conditions of the seal portion and the layer configuration of the laminate 30 so that the normal temperature seal strength after the retort treatment is less than or equal to a predetermined value, the hot seal strength below the desired value is obtained after the retort treatment. It was possible to produce a bag 10 having the same. Thereby, it could suppress that the laminated body 30 of the bag 10 had a hole in the case of a heating.

DESCRIPTION OF SYMBOLS 10 Bag 11 Upper part 11a Upper seal part 12 Lower part 12a Lower seal part 13 Side part 13a Side part seal part 14 Surface film 15 Back surface film 16 Lower film 17 Storage part 18 Contents 20 Vapor release mechanism 20a Vapor release seal part 30 Laminate 40 First plastic film 45 First adhesive layer 50 Second plastic film 55 Second adhesive layer 70 Sealant film 81 Sensor

Claims (11)

A bag having a receiving portion,
A laminate including a sealant film formed on the inner surface of the bag and made of a single layer, and at least one plastic film positioned on the outer surface side of the sealant film;
A seal portion that joins the inner surfaces of the pair of laminates,
The seal part is an outer edge seal part located on the outer edge of the bag, a steam release seal part located closer to the center point of the housing part than the outer edge seal part, and peeled off due to an increase in the pressure of the housing part, Have
The seal strength of the seal part at 25 ° C. is 60 N or less,
The bag whose sealing strength of the said seal part in case of 100 degreeC is 23 N or less.   The bag according to claim 1, wherein a product of a tensile elastic modulus (MPa) of the sealant film and a thickness (μm) of the sealant film in the flow direction is 35000 or more.   The bag according to claim 2, wherein a seal strength of the seal portion at 25 ° C is 55 N or less.   The bag according to claim 2 or 3 whose seal strength of said seal part at 25 ° C is 40 N or more.   The bag according to claim 2 or 3 whose seal strength of said seal part at 25 ° C is 45 N or more.   The bag according to any one of claims 1 to 5, wherein the sealant film contains a propylene / ethylene block copolymer as a main component.   The bag according to claim 6, wherein the sealant film includes a propylene / ethylene block copolymer as a main component and an α-olefin copolymer. A non-seal part isolated from the housing part by the steam release seal part;
The bag according to any one of claims 1 to 7, wherein the non-seal portion extends from a position closer to a center point of the housing portion than the outer edge seal portion to reach the outer edge of the bag.   The bag according to any one of claims 1 to 8, wherein a peeling pressure of the steam release seal portion is 133 kPa or less.   The bag according to any one of claims 1 to 8, wherein a peeling pressure of the steam release seal portion is 130 kPa or less. A method of manufacturing a bag having a storage part,
Preparing a laminate including a sealant film located on the inner surface of the bag and at least one plastic film located on the outer surface side of the sealant film;
The inner surfaces of the pair of laminates are heat-sealed at a predetermined sealing temperature, and the outer edge seal portion located on the outer edge of the bag is positioned closer to the center point side of the housing portion than the outer edge seal portion, and the housing A steam release seal part that peels off due to an increase in the pressure of the part, and a sealing step that forms a seal part,
Cutting the laminate in which the seal portion is formed to obtain a plurality of bags, and
The method for manufacturing a bag, wherein the sealing temperature in the sealing step is set so that the sealing strength of the sealing portion at 100 ° C. is 23 N or less.