JP6476511B2 - Packaging bag - Google Patents

Description

  The present invention relates to a packaging bag.

  In recent years, the use of microwave ovens has become essential for eating habits. In the packaging bag for food for microwave heating mainly made of solid matter such as pizza and hot apple pie, sufficient sealing property is required to maintain the quality until the product reaches the consumer. Furthermore, recently, it is required to be able to heat with a microwave as it is without opening the packaging bag in advance. If the packaging bag can be heated as it is in the microwave without opening it, the loss of moisture and aroma of the food can be suppressed as compared to the case where it is opened in advance and heated in the microwave, so the food can be tasted more .

As a packaging bag which has sufficient sealing property and can be heated by a microwave oven, without requiring preliminary operations, such as opening beforehand, the thing shown below, for example is known.
(1) A bag in which a laminated film consisting of an inner layer (low density polyethylene etc.), an intermediate layer (polyurethane adhesive etc.) and an outer layer (polyamide etc.) is sealed by heat sealing at the periphery so that the inner layers are joined. A packaging bag provided with a small hole zone in which a through hole penetrating the inner layer or a non-through hole not formed is formed in an inner layer near the edge of the bag (Patent Document 1).

  In the packaging bag of (1), when heated in a microwave oven, the vapor generated inside the bag forms a gap between the outer layer and the intermediate layer of the small pore zone, and the vapor is discharged from the edge of the bag through the gap Released. Therefore, even if the packaging bag is not opened before heating with a microwave oven, the steam is sufficiently released at the time of heating, and problems such as bursting of the bag at the time of heating and scattering of contents are prevented.

Patent No. 4785356

  However, in the conventional packaging bag like (1), when the film is softened by heating with a microwave, the force at the time of opening may be dispersed, and opening of the packaging bag may be difficult. If you try to open a packaging bag that can not be opened easily by force, it is important to be able to easily open the packaging bag after heating, as the contents may be splattered when the bag is opened. In particular, it is required to be able to be opened easily by hand without using tools such as scissors, for reasons such as an increase in consumers seeking convenience and barrier-free.

  An object of the present invention is to provide a packaging bag which is excellent in sealing property, allows sufficient steam to be released at the time of heating by a microwave without being opened in advance, and is easy to open after heating.

In the packaging bag of the present invention, the laminated film in which the base material and the sealant material are laminated is stacked such that the sealant materials face each other, and the sealant materials are fused to form a bag. An outer layer, wherein the sealant material is the innermost layer and has a back portion on the back side , it has a rectangular shape in plan view with one extending longitudinally, and the tensile strength of the sealant material is 8 to 20 N / 15 mm The tensile elastic modulus of the substrate is 550 MPa or more, and the sealant material is not penetrated only from the outer surface of the substrate to the laminated film only on the front side opposite to the backing portion easily openable portion is provided with a plurality of V-shape of the notch is extending in the longitudinal direction formed Nde parallel, the easily openable portion, on the front side, and the central portion in the width direction, the side end side of the both widthwise And formed respectively To have.

  The packaging bag of the present invention is excellent in sealing property, and the steam is sufficiently released at the time of heating by a microwave oven without being opened in advance, and the opening after heating is easy.

It is the top view which showed an example of the packaging bag of this invention. It is the enlarged plan view which expanded the easily openable part in the packaging bag of FIG. It is sectional drawing of the laminated film of the part which formed the easily openable part in the packaging bag of FIG.

Hereinafter, an example of the packaging bag of this invention is shown and demonstrated.
As shown in FIG. 1, the packaging bag 1 of the present embodiment is formed into a tubular shape by the back end portion 16 being formed by bonding both side end portions 12 and 14 of the laminated film 10 on the back surface. The upper end portion and the lower end portion are respectively heat-sealed to form an upper end seal portion 18 and a lower end seal portion 20, thereby forming a pillow-shaped packaging bag.

The shape of the packaging bag 1 in this example is a rectangular shape in plan view, in which the longitudinal direction of the backing portion 16, that is, the longitudinal direction, is longitudinal.
On the front face 1a of the packaging bag 1, as shown in FIG. 1, the first easy opening part 28, the second easy opening part 30, and the third easy opening part 32 (hereinafter, these may be collectively referred to as an easy opening part) ) Are formed to extend in the longitudinal direction from the upper end to the lower end of the packaging bag 1, respectively.
In the pillow-shaped packaging bag 1, the MD direction of the laminated film 10 is the length direction of the backing portion 16, that is, the longitudinal direction of the packaging bag 1 in the manufacturing process.

[Laminated film]
As shown in FIG. 3, the laminated film 10 is formed by bonding the base material 22 and the sealant material 24 via the adhesive layer 26.
In the packaging bag 1, in the backing portion 16, the sealants 24 are stacked so as to face each other, and the sealants 24 are fused. Also in the upper end seal portion 18 and the lower end seal portion 20, the sealants 24 are stacked so as to face each other, and the sealants 24 are fused.
In the packaging bag 1, the base material 22 is the outermost layer, and the sealant material 24 is the innermost layer.

The tensile modulus of elasticity of the base material 22 is 550 MPa or more. By the base material 22 having a high rigidity such as a tensile elastic modulus of 550 MPa or more, the internal pressure by the steam generated at the time of heating in the microwave oven is easily concentrated on the easy opening portion (in this example, particularly the second easy opening portion 30) Become. As a result, the base material 22 and the sealant material 24 are partially torn by the internal pressure in the easily opened portion to form a through hole, and the vapor can be released through the through hole. In addition, when the tensile modulus of elasticity of the substrate 22 is 550 MPa or more, the laminated film 10 can maintain sufficient rigidity even after being heated by the microwave oven. As a result, since it becomes difficult to disperse the force when opening the packaging bag 1 after heating, the packaging bag 1 can be easily opened using the easy-to-open part.

The tensile elastic modulus in the MD direction of the substrate 22 is 550 MPa or more, preferably 550 MPa to 1,500 MPa , and more preferably 600 MPa to 1,000 MPa . When the tensile elastic modulus in the MD direction of the base material 22 is equal to or more than the lower limit value, the packaging bag 1 can be easily opened. When the tensile elastic modulus in the MD direction of the base material 22 is equal to or less than the upper limit value, it is difficult to cause bending pinholes when the packaging bag 1 is handled.
The tensile elastic modulus in the TD direction of the base material 22 is 550 MPa or more, preferably 600 MPa to 2,500 MPa , and more preferably 750 MPa to 1,500 MPa , for the same reason as the tensile elastic modulus in the MD direction. .
In addition, the tensile elasticity modulus of MD direction of the base material 22 means the tensile elasticity modulus of MD direction (flow direction) of the base material 22 at the time of manufacture of the packaging bag 1. Further, the tensile elastic modulus in the TD direction of the base material 22 means the tensile elastic modulus in the TD direction (the direction perpendicular to the flow direction) of the base material 22 when the packaging bag 1 is manufactured.

  20 micrometers-40 micrometers are preferable, and, as for the thickness of the base material 22, 25 micrometers-30 micrometers are more preferable. When the thickness of the substrate 22 is equal to or more than the lower limit value, the packaging bag 1 can be easily opened. If the thickness of the base material 22 is equal to or less than the above-described upper limit value, bending pin holes are less likely to occur when the packaging bag 1 is handled.

  Specific examples of the substrate 22 include, for example, a biaxially stretched polyethylene terephthalate (PET) film, a biaxially stretched nylon (NYLON) film, a biaxially stretched polypropylene (PP) film, and a condition satisfying the tensile elastic modulus. Stretched vapor-deposited PET films, biaxially stretched vapor-deposited PP films, etc. may be mentioned. Among them, a biaxially stretched PP film which is less susceptible to physical properties due to heating steam due to its hydrophobicity and is also excellent in economy is preferable.

  The tensile strength of the sealant material 24 is 8 N / 15 mm to 20 N / 15 mm, preferably 10 N / 15 mm to 18 N / 15 mm, and more preferably 12 N / 15 mm to 15 N / 15 mm. If the tensile strength of the sealant 24 is equal to or more than the lower limit value, excellent sealing performance can be obtained. If the tensile strength of the sealant 24 is equal to or less than the upper limit, the cohesive force of the sealant 24 is sufficiently small, so the through hole is formed in the easily opened portion by the internal pressure by the steam generated at the time of heating in the microwave It becomes possible to withdraw.

  10 micrometers-30 micrometers are preferable, and, as for the thickness of the sealant material 24, 15 micrometers-20 micrometers are more preferable. If the thickness of the sealant 24 is equal to or more than the lower limit value, excellent sealing performance can be easily obtained. If the thickness of the sealant 24 is equal to or less than the upper limit value, vapor removal at the time of heating in a microwave oven becomes easy.

  As a material of the sealant 24, it is possible to use one having a function (easy peelability) that can be heat sealed and can be easily peeled off manually. Specifically, for example, polyolefin (low density polyethylene (LDPE), linear LDPE (LLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), PP, etc.), ethylene-vinyl acetate copolymer (EVA) And ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EMAA), ethylene-ethyl acrylate copolymer (EEA), ionomers, and mixtures of two or more of these. Among them, LDPE is preferable in terms of tensile strength and heat sealability.

The adhesive layer 26 is a layer that adheres the base material 22 and the sealant material 24.
As an adhesive component for forming the adhesive layer 26, a resin material having an adhesive function can be used. For example, an adhesive such as polyurethane, polyester, epoxy, polyvinyl acetate, etc .; acid-modified polyolefin, LDPE, LLDPE, modified The resin etc. which have heat adhesiveness, such as LDPE, are mentioned.

  The thickness of the adhesive layer 26 is preferably 1 μm to 4 μm, and more preferably 1 μm to 3 μm. When the thickness of the adhesive layer 26 is not less than the lower limit value, the adhesion between the base material 22 and the sealant 24 is sufficient. If the thickness of the adhesive layer 26 is equal to or less than the upper limit value, a through hole is easily formed at the time of heating in a microwave oven, and vapor removal becomes easy.

[Easy-to-open part]
The first easy opening part 28, the second easy opening part 30, and the third easy opening part 32 have a trigger for forming a through hole through which the vapor is released in the laminated film 10 by the internal pressure generated by the vapor generated at the time of heating by the microwave. Become. Also, it plays a role of inducing the cleavage of the laminated film 10 when the packaging bag 1 is opened after heating with a microwave oven.
In the present invention, as in the case of the packaging bag 1 of this example, it is preferable that the easy-to-open portion is formed to extend in the longitudinal direction of the packaging bag. As a result, the through hole is more easily formed in the easily opened portion by the steam at the time of heating by the microwave oven, and the steam escape becomes easier.

  As shown in FIGS. 1 to 3, in the laminated film 10 on the front surface 1 a of the packaging bag 1, the first easy-to-open part 28 is a plurality of cuts not penetrating the sealant material 24 from the outer surface of the base material 22 inward. 34 is formed by being linearly aligned in the longitudinal direction from the upper end to the lower end of the packaging bag 1. By forming each notch 34 so as not to penetrate the sealant material 24, sufficient sealing performance can be obtained.

In the first easy opening portion 28, a plurality of notches 34 having a C shape in plan view are formed in a straight line in parallel in three rows. Similarly, in the second easy opening section 30 and the third easy opening section 32 as well, a plurality of three-dimensional notches 34 are formed in a straight line in parallel. In the first easy-open section 28, a plurality of incisions 34 may be linearly formed in one line or two lines, and in a mode in which the plurality of incisions 34 are linearly formed in four or more lines It may be. Moreover, the 1st easily openable part 28 is not limited to the aspect extended linearly, For example, the aspect extended in a wavy line may be sufficient.
The same applies to the second easy opening section 30 and the third easy opening section 32.

  1.0 mm-2.5 mm are preferable and, as for length d 1 (length in the length direction of an easy-open part, FIG. 2) of the notch 34, 1.5 mm-2.0 mm are more preferable. If the length d1 of the notches 34 is equal to or more than the lower limit value, steam escape upon heating with a microwave oven becomes better, and opening after heating becomes easy. If the length d1 of the incision 34 is equal to or less than the upper limit value, the arrangement width of the incision can be narrowed, and it is easy to obtain straightness during opening.

The ratio (d2 / D) of the depth d2 (FIG. 3) of the notches 34 to the thickness D (FIG. 3) of the base material 22 is preferably 1/10 to 10/10, more preferably 4/10 to 10/10. Preferably, 6/10 to 10/10 is more preferable. If the ratio ratio (d 2 / D) is equal to or more than the lower limit value, vapor removal upon heating with a microwave oven becomes better, and opening after heating becomes easy.
In terms of the sealing property of the packaging bag 1, it is preferable that the cut 34 does not enter the sealant 24. In addition, as long as sufficient sealing performance can be ensured, the cut 34 may be included in the sealant 24.

  (FIG. 2) of the notch 34 of planar view V-shape is 45 degrees-85 degrees, and 60 degrees-80 degrees is more preferable. If the angle θ of the incision 34 is equal to or more than the lower limit value, cleavage propagation of the incision at the time of opening is easy to be continued, and opening becomes easy. If the angle θ of the incision 34 is equal to or less than the upper limit value, the incision is likely to be cleaved when heated by a microwave oven, and the vapor escapement becomes good.

-1.0 mm-1.0 mm are preferable, and-1.0 mm-0.5 mm are more preferable for the space | interval d3 (FIG. 2) of the notch 34 adjacent to the length direction of an easily opened part. If the interval d3 of the notches 34 is equal to or more than the above lower limit, even if the notches 34 are angled, the laminated film breaking direction at the time of opening can be easily guided in the longitudinal direction of the bag, and the opening of the packaging bag 1 can be facilitated. Become. If the interval d3 of the notches 34 is equal to or less than the upper limit value, the number of notches can be increased, and the vapor removal becomes good when heated by the microwave oven.
The negative value of the distance d3 means that the narrow end portion of the notch 34 in the plan view V shape has a wide width in the next cut 34 in the plan view V shape located on the tip end side Means intruding between the end parts.

  0.5 mm-3.0 mm are preferable and, as for the space | interval d4 (FIG. 2) of the notch 34 which adjoins the width direction in an easy opening part, 1.0 mm-2.0 mm are more preferable. If the interval d4 of the notches 34 is equal to or more than the lower limit value, the film rigidity between the notches can be secured, and the steam escape becomes good when heated by the microwave oven. When the interval d4 of the notches 34 is equal to or less than the upper limit value, the laminated film is easily cleaved along the easy opening portion, so that the opening of the packaging bag 1 is facilitated.

  In the present invention, like the first easily openable portion 28, the second easy openable portion 30 and the third easy openable portion 32 of the packaging bag 1, the center portion in the width direction of the packaging bag and both side ends in the width direction It is preferable that the easy-opened part is formed on each of the two. Thereby, particularly in the easy opening portion formed in the central portion in the width direction, the through hole is easily formed at the time of heating with the microwave oven, and the vapor escape at the time of heating becomes better. In addition, the packaging bag can be easily opened after heating.

  The position in the width direction of the first easy-to-open part 28 in the packaging bag 1 is L on the width of the packaging bag 1 (FIG. 1), and the first side edge 1b (the side close to the first easy-to-open part 28) in the packaging bag 1 When the distance from the side edge) to the center in the width direction of the first easy opening portion 28 is a (FIG. 1), a position where a / L is 1/10 to 6/10 is preferable, and 1/10 to 3 A position of 10 is more preferable. If the position in the width direction of the first easily openable portion 28 is a position where a / L falls within the above range, vapor removal at the time of heating in a microwave oven becomes easier.

The position in the width direction of the second easy-to-open part 30 in the packaging bag 1 is defined as the distance b from the first side edge 1 b of the packaging bag 1 to the center in the width direction of the second easy-to-open part 30 (FIG. 1) When, in the range between the first easy opening part 28 and the third easy opening part 32, a position where b / L is 3/10 to 7/10 is preferable, and a position where 4/10 to 6/10 is More preferable. If the position in the width direction of the second easily openable portion 30 is a position at which b / L falls within the above range, steam removal at the time of heating in a microwave oven becomes easier.
Moreover, the position of the width direction of the 2nd easy opening part 30 is the width of the packaging bag 1 from the point which a penetration hole is easily formed in the 2nd easy opening part 30 at the time of heating in a microwave oven, and vapor removal becomes easier. Preferably it is offset from the center of the direction. That is, as for the position of the width direction of the 2nd easy-to-open part 30, b / L is more preferably 3/10 or more and less than 5/10, or more than 5/10 and 7/10 or less, and b / L is 4 / A position of 10 or more and less than 5/10, or more than 5/10 and 6/10 or less is particularly preferable.

  The position in the width direction of the third easy-to-open part 32 in the packaging bag 1 is c (FIG. 1) the distance from the first side edge 1 b of the packaging bag 1 to the center in the width direction of the third easy-to-open part 32 When c / L is 4/10 to 9/10 within the range of the second side edge (the side edge opposite to the first side edge 1a) of the packaging bag 1 than the first easy opening section 28 Position is preferable, and a position of 7/10 to 9/10 is more preferable. If the position in the width direction of the third easily openable portion 32 is a position at which c / L falls within the above range, steam removal at the time of heating in a microwave oven becomes easier.

  In addition, the number of easy-to-open parts may be one or two, or four or more. In addition, the easy-to-open part is not limited to the aspect formed in a straight line, and may be an aspect formed in a wavy line, for example.

[Production method]
It does not specifically limit as a manufacturing method of laminated | multilayer film 10, For example, the method of having the following process (a), process (b), process (c), process (d), and process (e) is mentioned.
(A) A process of manufacturing the base material 22.
(B) forming the first easy opening portion 28, the second easy opening portion 30, and the third easy opening portion 32 at predetermined positions of the base material 22;
(C) A process of manufacturing the sealant material 24.
(D) a step of laminating the base material 22 and the sealant material 24 to obtain a laminated film 10;
(E) A step of forming the laminated film 10 to obtain the packaging bag 1.

(Step (a), step (c))
A known method can be adopted as a method of producing the base material 22 and the sealant material 24, and extrusion molding, inflation molding and the like can be mentioned.

(Step (b))
It does not specifically limit as a method to form the 1st easily opened part 28, the 2nd easily opened part 30, and the 3rd easy opened part 32 in the base material 22, For example, the needle-like protrusion of planar view V shape is an outer peripheral surface The first easy opening portion 28, the second easy opening portion 30, and the third easy opening portion 34 are formed by forming the notches 34 linearly in the MD direction of the base material 22 using a large number of rolls formed in the circumferential direction. The method of forming the part 32 is mentioned.
Step (b) is preferably performed before step (d). By performing the step (b) before the step (d), it becomes easy to prevent the cut from being formed in the sealant material. In addition, if it is a range which does not impair sufficient sealing performance, you may perform a process (b) after a process (d).

(Step (d))
It does not specifically limit as a method to laminate the base material 22 and the sealant material 24, For example, after applying an adhesive agent to any one or both of the base material 22 and the sealant material 24, they are laminated and it is dry. The lamination method is mentioned. Alternatively, a sand lamination method may be used in which a resin to be the adhesive layer 26 is extrusion molded as a molten film, and the base material 22 and the sealant material 24 are laminated on both surfaces of the molten film.

(Step (e))
As a method of obtaining the packaging bag 1, a known method can be adopted except using the laminated film 10, and the following method can be mentioned, for example.
The two side ends 12 and 14 of the laminated film 10 are stacked on the back so that the sealants 24 face each other, and they are heat sealed to form a backing portion 16. Next, the lower end portion of the tubular laminated film 10 in which the backing portion 16 is formed is heat-sealed to form the lower end sealing portion 20. Next, the contents such as pizza are accommodated in the bag from the upper opening, and the upper end is heat-sealed to form the upper seal 18 and sealed to obtain the packaging bag 1.

[Function effect]
In the packaging bag of the present invention described above, the easy-opened portion is formed in which the incisions extending inward from the outer surface of the base are formed in an arbitrary direction, which occurs during heating in a microwave oven Due to the internal pressure generated by the steam, the easy-to-open portion is partially cleaved to form a through hole, and the steam is released through the through hole. In particular, in the present invention, the internal pressure due to the steam tends to be concentrated on the easily openable portion because the rigidity of the base material is high. Furthermore, since the cohesion of the sealant 24 is sufficiently small because the tensile strength of the sealant 24 is controlled within a specific range, the sealant 24 easily peels off from the substrate 22 at the easily opened portion by the internal pressure. From these things, a through-hole is easy to be formed in an easily opened part at the time of a heating, and vapor | steam extraction can be performed favorable. Therefore, in the case of the packaging bag of the present invention, it is possible to suppress such a problem that the bag is ruptured and the contents are scattered at the time of heating in the microwave oven.
Furthermore, in the present invention, the rigidity of the substrate is sufficiently high even after heating because the rigidity of the substrate is high. As a result, by making it difficult to disperse the force at the time of opening after heating, the packaging bag can be easily opened using the easy opening part.
Further, in the packaging bag of the present invention, each notch forming the easy-to-open portion is formed so as not to penetrate the sealant material, and furthermore, the tensile strength of the sealant material 24 is controlled within a specific range. Sealability is also secured.
As described above, in the packaging bag of the present invention, while ensuring excellent sealing performance, it is possible to heat in a microwave oven without opening it, and contradictory demands to obtain further excellent easy opening property, so-called antinomy. The characteristics can be compatible. Moreover, since the packaging bag of this invention can also utilize the bag itself after opening as a substitute of a plate, it is useful also in the point which can taste food, without polluting a plate etc.

The packaging bag of the present invention is not limited to the packaging bag 1 described above.
For example, the packaging bag of the present invention may be in the form of a three-way sealing bag, a four-way sealing bag or the like. In the packaging bag of the present invention, the easy-to-open part may be formed in the width direction of the packaging bag.
Further, the packaging bag of the present invention is not limited to the aspect in which the easy-to-open part extends in the longitudinal direction of the packaging bag, and for example, the easy-to-open part may be a packaging bag extending in the lateral direction. In the packaging bag of the present invention, the MD direction of the laminated film may be in the width direction of the packaging bag.

Moreover, the packaging bag of this invention may use the laminated | multilayer film which does not have an adhesive layer. Specifically, for example, it may be a packaging bag using a laminated film obtained by co-extruding the base material and the sealant material and then forming a cut from the surface of the base material toward the inside.
Moreover, in the packaging bag of the present invention, in order to further enhance the easy opening property, a fine scratch of about 0.5 mm R is made 1 mm ^{2 on} either or both of the base material and the sealant material at the end of the easy opening part. It is good also as an aspect formed 10 or more per.

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited by the following description.
[Tensile modulus]
According to JIS K7127, the tensile elastic modulus ( MPa ) of the substrate in the MD and TD directions was measured under the following conditions.
(Test conditions)
Specimen: Specimen type 2
Measurement temperature: 23 ° C.
Measuring instrument: Strograph E3-L (made by Toyo Seiki Seisaku-sho, Ltd.).
Tensile speed: 300 mm / min.

[tensile strength]
The tensile strength (N / 15 mm) of the sealant material was measured in accordance with JIS Z1702 under the following conditions.
(Test conditions)
Test specimen: 15 mm wide.
Measurement temperature: 23 ° C.
Measuring instrument: Strograph E3-L (made by Toyo Seiki Seisaku-sho, Ltd.).
Tensile speed: 500 mm / min.

[Steaming out]
After freezing the packaging bag containing the pizza obtained in each example with a freezer, heating is performed for 2 minutes with a microwave oven (output 500 W) with the surface on which the easy-to-open part is formed upward, and steam escape from the packaging bag The condition of was visually confirmed and evaluated according to the following criteria.
:: The vapor is ejected from the second easy opening section 30 without the popping sound.
:: Steam is ejected from the first easily openable unit 28 or the third easy opener 32 without a bursting sound.
Δ: Steam is ejected from the easy-to-open part with a small popping sound.
X: Steam blows out from the easy-to-open part together with a loud popping sound.

[Easy openability]
After heating with a microwave oven in the evaluation of vapor escape, the packaging bag was manually opened manually using the easy opening part, and the feel at that time was evaluated according to the following criteria.
○: Can be opened easily along the easy opening part.
Δ: Can be opened along the easy opening part.
X: Can not be opened along the easy opening part.

[Sealing]
The pizza-containing packaging bag obtained in each example was frozen in a freezer and the packaging bag was dropped three times from a height of 1.2 m, and then the lower end seal of the packaging bag was opened and the pizza was taken out. . Thereafter, a check solution (red) of Ageless Seal Check Spray (manufactured by Mitsubishi Gas Chemical Company, Inc.) was sprayed onto the upper end seal portion from the inside of the packaging bag. The packaging bag was suspended with the upper end seal portion vertically downward, and after 24 hours, the upper end seal portion was observed and evaluated according to the following criteria.
○: Penetration of the check solution to the upper end seal is not observed.
X: Penetration of the check liquid to the upper end seal portion is observed.

Example 1
Base material biaxially oriented polypropylene film (trade name "Pyrene film-OT", Toyobo Co., Ltd., thickness 30 μm, tensile modulus in MD direction: 660 MPa , tensile modulus in TD direction: 960 MPa ), sealant material Using a laminated film of low density polyethylene film (trade name “Polyster LD”, manufactured by Star Plastics Industry Co., Ltd., thickness 20 μm, tensile strength: 15 N / 15 mm), and illustrated in FIGS. The packaging bag 1 (length 220 mm x width 200 mm) was produced. The packaging bag 1 heat-sealed the opening and sealed it, after accommodating a pizza 120 g inside.
In addition, before forming into a laminated film, a plurality of incisions having a C shape in plan view are formed in parallel in a straight line by using a roll having a large number of needle-like projections formed on the outer peripheral surface before forming a laminated film. The first easy opening part, the second easy opening part and the third easy opening part were formed in the MD direction of the base material (longitudinal direction of the packaging bag 1). In addition, the MD direction of the base material (MD direction of the laminated film) was made to be the vertical direction of the packaging bag 1. Each planar V-shaped cut has a length d1 of 1.6 mm, a depth d2 of 30 μm, a d / 10 ratio of d2 / D, an angle θ of 60 °, a distance d3 of 0.5 mm, and a width of about 3 mm The distance d4 in the direction is 1 mm. Further, the positions of the first easy-opening part, the second easy-opening part and the third easy-opening part in the width direction of the packaging bag 1 are a / L 2/10, b / L 4/10, c / It was made for L to be 8/10.

[Examples 2 to 16]
A packaging bag was produced in the same manner as in Example 1 except that the configuration of the laminated film and the conditions of the easy-opened part were changed as shown in Table 1 and Table 2.

Comparative Examples 1 to 3
A packaging bag was produced in the same manner as in Example 1 except that the configuration of the laminated film and the condition of the easy-to-open part were changed as shown in Table 2.

Tables 1 and 2 show the evaluation results for the packaging bags of the example and the comparative example.
In addition, the inside of the parenthesis of the column of the structure of the laminated film in Table 1 and Table 2 shows the thickness of each film. The abbreviations in Tables 1 and 2 have the following meanings.
OPP: biaxially stretched polypropylene film (trade name "Pyrene film-OT", manufactured by Toyobo Co., Ltd.).
LDPE: Low density polyethylene film (trade name "Polystar LD", manufactured by Star Plastics Industry Co., Ltd.).
PET: polyethylene terephthalate film (trade name "Toyobo ester film", manufactured by Toyobo Co., Ltd.).

As shown in Tables 1 and 2, using a laminated film in which a substrate having a tensile modulus of 550 MPa or more and a sealant material having a tensile strength of 8 to 20 N / 15 mm are laminated, the sealant is directed inward from the outer surface of the substrate In Examples 1 to 16 in which the easy-to-open portion formed of a plurality of incisions that do not penetrate the material is formed, the sealing property is excellent, the vapor escapes at the time of heating in the microwave oven is good, and the easy-opening property after heating is also excellent. It was
On the other hand, in Comparative Example 1 using a substrate having a tensile modulus of less than 550 MPa and Comparative Example 2 using a sealant material having a tensile strength of more than 20 N / 15 mm, the sealing property was excellent, heating in a microwave oven Sometimes the steam was not sufficiently released and the easy openability after heating was also inferior.
In addition, in Comparative Example 3 using a sealant material having a tensile strength of less than 8 N / 15 mm, the vapor escape upon heating in a microwave oven was good, and although easy openability after heating was excellent, sufficient sealing performance was obtained. It was not done.

DESCRIPTION OF SYMBOLS 1 packaging bag 10 laminated film 12, 14 side edge part 16 back extension part 18 upper end seal part 20 lower end seal part 22 base material 24 sealant material 26 adhesive layer 28 1st easy opening part 30 2nd easy opening part 32 3rd easy opening Part 34 Infeed

Claims (1)

A laminated film in which a substrate and a sealant material are laminated is stacked so that the sealant materials face each other, and the sealant materials are fused to form a bag, and the substrate is the outermost layer, the sealant material Is the innermost layer, and
It is a rectangular shape in plan view having a backing portion on the back side, one of which is longitudinal,
The tensile strength of the sealant material is 8 to 20 N / 15 mm,
The tensile modulus of elasticity of the substrate is 550 MPa or more,
Only in the laminated film opposite the front side and the back tension part, toward the inside from the outer surface of the base material, the longitudinal direction in which the plurality of V-shape of the notch does not penetrate the sealant material is formed Nde parallel easy-to-open portion is provided extending to,
The easily openable part is a packaging bag formed on the front side in the center in the width direction and near both side ends in the width direction .

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