Laminated film and pouch

Abstract

To provide a laminate film capable of easily showing a completion of a heat treatment without using a specific tool or process, and also to provide a pouch using such a laminate film.SOLUTION: A pouch includes at least a first face film, a second face film, and a housing part between the first face film and the second face film. The pouch includes: a first edge and a second edge facing the first edge; and a first side edge and a second side edge extending between the first edge and the second edge. At least one film defining the housing part is composed of a laminate film including a transparent substrate layer 51, an adhesive layer 52, a vapor deposition substrate layer 53, and a sealant layer 56 sequentially from an outside. The vapor deposition substrate layer 53 includes a metal deposition layer 53A arranged on a side having contact with the adhesive layer 52. The adhesive layer 52 includes a no-adhesive coating part 52a in a prescribed pattern that executes a prescribed display.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a laminated film whose display changes due to heat, and a pouch using the laminated film.

Background Art

[0002] Conventionally, when performing sterilization treatment by heating such as boiling sterilization or retort sterilization, as evidence of having performed the sterilization treatment, it has been carried out to indicate that it has been sterilized by a sterilization indicator. When providing a sterilization indicator, taping or printing with a special ink has been carried out (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional technology, in order to provide a sterilization indicator, a taping process or printing with a special ink is required. For this reason, there are problems such as the process becoming complicated and the cost increasing. Therefore, a technique for confirming that heat has been applied by a simple process is required.

[0005]

Means for Solving the Problems

[0006] In order to solve the above problems, the present invention is laminated in order with a transparent base material layer, an adhesive layer, a vapor deposition base material layer, and a sealant layer, The vapor deposition base material layer has a metal vapor deposition layer disposed on the side in contact with the adhesive layer. The adhesive layer provides a laminated film having an adhesive non-coated portion in a predetermined pattern for performing a predetermined display.

[0007] Also, the laminated film of the present invention The transparent base material layer may be a transparent vapor deposition film in which a metal oxide or an inorganic oxide is vapor deposited on a transparent base material and a transparent film base material.

[0008] Also, the laminated film of the present invention The metal contained in the metal vapor deposition layer may be aluminum.

[0009] Also, the present invention A pouch having at least a first surface film and a second surface film, and having a storage portion between the first surface film and the second surface film, the pouch having a first edge, a second edge facing the first edge, and a first side edge and a second side edge extending between the first edge and the second edge. At least one of the films defining the storage portion is composed of a laminated film including a transparent base material layer, an adhesive layer, a vapor deposition base material layer, and a sealant layer in this order from the outer surface. The vapor deposition base material layer has a metal vapor deposition layer disposed on the side in contact with the adhesive layer. The adhesive layer has a non-coated portion of the adhesive in a predetermined pattern for performing a predetermined display. A pouch is provided.

[0010] Also, the pouch of the present invention The transparent base material layer may be a transparent vapor deposition film in which a metal oxide or an inorganic oxide is vapor deposited on a transparent film base material.

[0011] Also, the pouch of the present invention The metal contained in the metal vapor deposition layer may be aluminum.

Advantages of the Invention

[0012] According to the present invention, it becomes possible to easily show that sterilization treatment has been performed without using special materials or processes.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0014] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a front view showing a pouch according to an embodiment of the present invention. Further, FIG. 2 is an exploded view showing a film configuration constituting a pouch according to an embodiment of the present invention. The pouch in the embodiment shown in FIG. 1 shows the pouch in a state before the content is filled (a state where the content is not filled). The pouch of the present embodiment is rectangular in plan view and has a bottom gusset portion. In the present embodiment, the rectangle is a concept including not only a rectangle with right-angled corners but also a rectangle with rounded corners and an outwardly convex arc shape. In the present invention, the pouch is a concept including not only a pouch in a state where the content is not filled but also a pouch in a state where the content is filled.

[0015] As shown in FIG. 1, the pouch of the present embodiment has at least a first surface film 1 and a second surface film 2, and includes a first edge portion 4, a second edge portion 5 facing the first edge portion 4, a first side edge portion 6 and a second side edge portion 7 extending between the first edge portion 4 and the second edge portion 5.

[0016] <<Constituent members>> As shown in FIG. 2, the pouch of the present embodiment is composed of three members (films): a substantially rectangular first surface film 1, a second surface film 2 having the same shape as the first surface film 1, and a substantially rectangular bottom film 3. The pouch of the present embodiment is formed by sealing (heat-sealing) the three films of the first surface film 1, the second surface film 2, and the bottom film 3 at predetermined locations.

[0017] As shown in FIG. 2, the bottom film 3 is folded in half and is divided into a first portion 3f and a second portion 3g with the folding portion 3a as a boundary. Four semi-circular cutout portions 3b, 3c, 3d, and 3e are provided on the bottom film 3 so as to notch the side edges, and the cutout portions 3b and 3c, and the cutout portions 3d and 3e are provided at corresponding positions when folded in half. Through these cutout portions 3b to 3e, a second bottom seal portion 15b described later is formed. Also, from the viewpoint of stabilizing the self-standing property as a standing pouch, the distance L1 from the folding portion 3a to the second edge portion 5 of the pouch in the direction orthogonal to the folding portion 3a can be appropriately designed in consideration of the self-standing property of the pouch. For example, when the distance L1 is 35 mm or more, the self-standing property of the pouch is further enhanced.

[0018] <<Each seal portion>> As shown in Fig. 1, the pouch of this embodiment includes a first side edge seal portion 16, a second side edge seal portion 17, a first bottom seal portion 15a, and a second bottom seal portion 15b, and an opening 12 is formed in the first edge 4. In Fig. 1, each seal portion is indicated by diagonal hatching. In this embodiment, each seal portion is obtained by joining by welding sealants facing each other by heat sealing. Heat sealing can be performed by a known method such as bar sealing, rotary roll sealing, belt sealing, impulse sealing, high-frequency sealing, ultrasonic sealing, etc. Note that the seal portion may be formed by adhering opposing films with an adhesive.

[0019] The first side edge seal portion 16 and the second side edge seal portion 17 are formed by sealing and joining the first surface film 1 and the second surface film 2. The first side edge seal portion 16 is formed to include the first side edge 6 (the left end in Fig. 1), and the second side edge seal portion 17 is formed to include the second side edge 7 (the right end in Fig. 1). The seal width W1 of the first side edge seal portion 16 and the second side edge seal portion 17 is preferably 5 mm or more and 15 mm or less. Note that the seal width W1 is the width in the direction orthogonal to the direction in which the seal portion extends.

[0020] The bottom seal portion 15 is a seal portion formed below the folding portion 3a, and is composed of a first bottom seal portion 15a and a second bottom seal portion 15b. The first bottom seal portion 15a is formed by sealing the first surface film 1 and the first portion 3f of the bottom surface film 3, and the second surface film 2 and the second portion 3g of the bottom surface film 3. The second bottom seal portion 15b is formed by sealing the first surface film 1 and the second surface film 2.

[0021] <<Bottom gusset portion>> A first fold is formed by the first part 3f of the bottom film 3 and the part of the first surface film 1 corresponding to the first part 3f of the bottom film 3, and a second fold is formed by the second part 3g of the bottom film 3 and the part of the second surface film 2 corresponding to the second part 3g of the bottom film 3. And the bottom gusset part 9 is formed by the first fold and the second fold. In the front view of Fig. 1, the first fold is visible below the folding part 3a.

[0022] <<Container>> After the contents are accommodated through the opening 12, a first edge seal part 14 (see Fig. 3) is formed at the first edge seal planned part 14a (above the dashed line) shown in Fig. 1, and the pouch is sealed. Fig. 3 is a front view showing the pouch in a state where the first edge 4 side is sealed. In Fig. 3, for the sake of convenience of explanation, the illustration of the contents is omitted. The first edge seal part 14 is formed from the first side edge seal part 16 to the second side edge seal part 17. The accommodating part 11 is defined by the inner edge of the first side edge seal part 16, the inner edge of the second side edge seal part 17, the inner edge of the first bottom seal part 15a, and the inner edge of the first edge seal part 14.

[0023] <<Contents>> Examples of the contents include foods suitable for boiled or retort foods. For example, curry, stew, soup, meat sauce, hamburger, meatball, shumai, oden, and other foods can be mentioned.

[0024] <<Details of the film>> As the first surface film 1, second surface film 2, and bottom surface film 3 constituting the pouch, laminated films can be used. The laminated film is at least a laminate including a base material layer and a sealant layer from the outside. For example, the laminated film is formed by laminating, in order from the outside, a base material layer, a printing layer, other layers, and a sealant layer. The printing layer and other layers are not essential. The sealant layer is the layer that constitutes the innermost surface of the pouch. When the pouch requires heat resistance, the base material layer is preferably made of a heat-resistant material. For example, as the material of the base material layer, polyester films such as polyethylene terephthalate and polybutylene terephthalate, polyamide films such as nylon, and polypropylene films can be used. The thickness is preferably 10 μm or more and 50 μm or less. Also, the base material layer is preferably biaxially stretched.

[0025] Also, the laminated film may include a plurality of base material layers. As the plurality of base material layers, a first base material layer and a second base material layer can be provided. As the first base material layer and the second base material layer, appropriate combinations can be adopted from the above materials. For example, polyethylene terephthalate can be used as the first base material layer which is the outermost layer, and polyamide can be used as the second base material layer which is the inner layer (on the sealant layer side). The second base material layer extends from one side edge portion toward the other side edge portion. As the second base material layer, for example, "Emblem (registered trademark) NC" manufactured by Unitika Ltd., which contains MXD (meta-xylenediamine) with excellent barrier properties, can be used. Also, as the second base material layer, polyesters such as "Embret (registered trademark) PC" manufactured by Unitika Ltd. and "Embret (registered trademark) PCBC" manufactured by Unitika Ltd. may be used. The first base material layer and the second base material layer can be laminated using, for example, the dry lamination method.

[0026] The printing layer is provided for displaying product content, imparting aesthetic sense, or displaying the cut part. The printing layer is formed by printing ink containing a binder and pigments. The sealant layer is disposed on the innermost side when the laminated film is made into a pouch by bag-making. As the material of the sealant layer, polyolefin resins such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer, and ethylene-propylene block copolymer can be adopted. The thickness of the sealant layer is preferably 30 μm or more and 100 μm or less. Also, the sealant layer is preferably non-stretched.

[0027] As the sealant layer, in order to be easily peelable, one with easy peelability can also be used. To impart easy peelability, the sealant layer can contain an easily peelable thermoplastic resin. As the easily peelable thermo-adhesive resin, a modified polyolefin resin mainly composed of ethylene-vinyl acetate copolymer can be used. As the easily peelable thermo-adhesive resin, for example, TAF-650C manufactured by Mitsui Chemicals Toagosei Co., Ltd., 7601A manufactured by Toray Film Processing Co., Ltd., 9501E manufactured by Toray Film Processing Co., Ltd., SMX manufactured by J Film Co., Ltd., etc. can be preferably used.

[0028] The laminated film may contain other layers. The other layers may be provided outside the base material layer or between the base material layer and the sealant layer. As the other layers, appropriate ones are selected according to the required functions such as water vapor and other gas barrier properties, light shielding properties, etc. For example, when the other layer is a gas barrier layer, a vapor deposition layer of a metal such as aluminum, a metal oxide such as aluminum oxide, or an inorganic oxide such as silicon oxide is provided. The vapor deposition layer may be laminated on the base material layer or vapor-deposited on the sealant layer. Alternatively, a metal foil such as aluminum may be provided. In addition, a resin layer having gas barrier properties such as ethylene-vinyl alcohol copolymer (EVOH), polyvinylidene chloride resin (PVDC), or aromatic polyamide such as nylon MXD6 may be provided. Each layer can be laminated using a dry lamination method, a melt extrusion method, or the like.

[0029] In the case of the dry lamination method, an adhesive layer is formed using an adhesive for lamination. As the adhesive, for example, a solvent-based, water-based, or emulsion-type adhesive such as a one-component or two-component curable or non-curable type of vinyl-based, (meth)acrylic-based, polyamide-based, polyester-based, polyether-based, polyurethane-based, epoxy-based, rubber-based, or other adhesives can be used. As the two-component curable adhesive, a cured product of a polyol and an isocyanate compound can be used. As the coating method of the above-mentioned adhesive for lamination, for example, it can be applied to the coating surface of the layer constituting the laminate by a direct gravure roll coating method, a gravure roll coating method, a kiss coating method, a reverse roll coating method, a fountain method, a transfer roll coating method, or other methods.

[0030] In the case of the melt extrusion method (extrusion lamination method), an adhesive resin layer is formed and adhered with a thermoplastic resin. As the thermoplastic resin, a polyethylene-based resin, a polypropylene-based resin, a cyclic polyolefin-based resin, a copolymer resin, a modified resin, or a mixture (including a polymer alloy) mainly composed of these resins can be used. As the polyolefin-based resin, for example, the above-mentioned polyethylene, polypropylene (PP), ethylene-α-olefin copolymer polymerized using a metallocene catalyst, random or block copolymer of ethylene and polypropylene, ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ethylene-maleic acid copolymer, ionomer resin, and, in order to improve the adhesion between layers, the above-mentioned polyolefin-based resin modified with an unsaturated carboxylic acid such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, etc., such as an acid-modified polyolefin-based resin can be used.

[0031] In this embodiment, as the first surface film 1, the second surface film 2, and the bottom surface film 3, a laminated film having two base material layers is used. The base material layer on the outer surface side is a transparent base material layer that is transparent, and the base material layer on the inner surface side is a vapor deposition base material layer on which metal is vapor-deposited. And, as the first surface film 1, a laminated film 50A having a display function by heat is used, and as the second surface film 2 and the bottom surface film 3, a laminated film 50B having no display function by heat is used. Both the laminated film 50A and the laminated film 50B include a transparent base material layer and a vapor deposition base material layer, but the configuration of the adhesive layer is different. FIG. 4 is a diagram showing the layer configuration of the laminated film according to an embodiment of the present invention. Among these, FIG. 4(a) is a diagram showing the laminated film 50A having a display function by heat, and FIG. 4(b) is a diagram showing the laminated film 50B having no display function by heat.

[0032] First, the laminated film 50B having no display function by heat will be described. As shown in FIG. 4(b), the laminated film 50B is a laminate including, from the outside, a transparent base material layer 51, an adhesive layer 59, a vapor deposition base material layer 53 (metal vapor deposition layer 53A, base film 53B), an adhesive layer 55, and a sealant layer 56. The transparent base material layer 51 is a transparent base material layer using a transparent film base material. The transparent base material layer 51 located on the outermost surface needs to be transparent so that the inner surface side can be visually recognized. In this embodiment, the transparent base material layer 51 is a transparent vapor deposition film in which a metal oxide or an inorganic oxide is vapor-deposited on a transparent film base material. The adhesive layer 59 is an adhesive layer formed by applying an adhesive for lamination. The vapor deposition base material layer 53 is a metal vapor deposition film in which a metal vapor deposition layer 53A is formed on the base film 53B by vapor-depositing metal. The adhesive layer 55 is an adhesive resin layer that adheres the base film 53B of the vapor deposition base material layer 53 and the sealant layer 56 by a melt extrusion method. The sealant layer 56 is a layer for heat-sealing and welding with the sealant layer of the opposing laminated film. In FIG. 4, the printing layer is omitted for both the laminated film 50A having a display function and the laminated film 50B having no display function, but a printing layer using printing ink can be formed as needed.

[0033] In this embodiment, as the first surface film 1, a laminated film 50A having a display function by heat is used. As shown in Fig. 4(a), the laminated film 50A is a laminate including at least, from the outside, a transparent base material layer 51, an adhesive layer 52, a vapor deposition base material layer 53 (a metal vapor deposition layer 53A and a base film 53B), an adhesive layer 55, and a sealant layer 56. When compared with the laminated film 50B having no display function by heat, the materials of each of the transparent base material layer 51, the vapor deposition base material layer 53 (the metal vapor deposition layer 53A and the base film 53B), the adhesive layer 55, and the sealant layer 56 are the same as those of the laminated film 50B.

[0034] Unlike the adhesive layer 59 of the laminated film 50B, the adhesive layer 52 of the laminated film 50A includes an adhesive non-coated portion 52a where no adhesive is applied. The adhesive layer 52 is located on the outer surface side of the metal vapor deposition layer 53A. Of the vapor deposition base material layer 53, the outer surface side is the metal vapor deposition layer 53A, and the inner surface side is the base film 53B. Therefore, the adhesive layer 52 is in contact with the metal vapor deposition layer 53A of the vapor deposition base material layer 53. The adhesive used for the adhesive layer 52 may be the same as or different from the adhesive used for the adhesive layer 59 of the laminated film 50B.

[0035] <<Opening means>> In this embodiment, an opening means is formed at a position near the first edge 4. The opening means includes an opening start means 18 and an easy-opening line 19. The opening start means 18 is a notch and is provided at the first side edge seal portion 16 and the second side edge seal portion 17. The opening start means 18 may be a cutout. These opening start means may be provided on only one of the first side edge seal portion 16 and the second side edge seal portion 17. The easy-opening line 19 is a line extending from the first side edge seal portion 16 toward the second side edge seal portion 17. The easy-opening line may be a half-cut line that penetrates the base material layer and does not penetrate the sealant layer. The half-cut line may be formed using a cutting tool or by laser processing. Also, the easy-opening line 19 may be a continuously extending line or a discontinuously extending line. Further, the easy-opening line 19 may be provided so as to reach from one side edge of the pouch to the other side edge.

[0036] In this embodiment, the easy-opening line 19 is realized by a half-cut line. Here, the half-cut line means a line that does not penetrate all the layers of the laminated film. In this embodiment, the easy-opening line 19 is a half-cut line that penetrates the transparent base material layer 51 and the vapor deposition base material layer 53.

[0037] <<Manufacturing Method>> Next, the manufacturing method of the pouch according to this embodiment will be described. Prepare the first surface film 1, the second surface film 2, and the bottom film 3, which are three laminated films. Among these, as at least one film, prepare a laminated film 50A having a heat display function. All of the first surface film 1, the second surface film 2, and the bottom film 3 may be the laminated film 50A having a heat display function. Then, as shown in FIG. 2, for the first surface film 1 and the second surface film 2, the easy-opening line 19 is formed on the outermost base material layer, which is the surface on the side not facing each other. Then, as shown in FIG. 2, the bottom film 3 is folded back at the folding portion 3a and sandwiched between the first surface film 1 and the second surface film 2. Then, by heat-sealing the bottom portion on the second edge portion 5 side, the first side edge portion 6, and the second side edge portion 7, the first side edge portion seal portion 16, the second side edge portion seal portion 17, the first bottom seal portion 15a, and the second bottom seal portion 15b are formed, and a pouch having an opening 12 as shown in FIG. 1 is obtained. Then, after filling the contents from the opening 12 and accommodating them in the accommodating portion 11, the first edge portion 4 is heat-sealed to form the first edge portion seal portion 14, thereby obtaining a pouch in which the contents are accommodated.

[0038] <<During Use>> The pouch containing the contents is distributed in the market as a product, displayed in stores, etc., and delivered to the end consumer. The consumer starts opening from the opening start means 18 such as a cut. Specifically, by grasping the upper and lower sides of the opening start means 18 and applying forces in opposite directions to each other, the cut is enlarged. The cut enlarged from the opening start means 18 will eventually reach the easy opening line 19. Further, when a force is applied, cuts are made along the easy opening line 19 also in the layers other than the transparent base material layer 51 and the vapor deposition base material layer 53 of the first surface film 1 and the second surface film 2, and the portion on the first edge 4 side from the opening start means 18 and the easy opening line 19 of the pouch is separated. Then, the contents can be taken out from the portion opened by the easy opening line 19.

[0039] [[Function]] Next, the action when heating the laminated film 50A having a display function by heat will be described. When heating a pouch manufactured using the laminated film 50A as shown in Fig. 4(a) from the outer surface side at a predetermined temperature, heat and moisture are accumulated in the non-coated portion 52a of the adhesive layer 52 in the laminated film 50A. Then, the heat and moisture accumulated in the non-coated portion 52a erode the adjacent metal vapor deposition layer 53A. Specifically, a reaction occurs as shown by the chemical formula in the following [Formula 1].

[0040] [Formula 1] 2AL + 6H 2 O → 2AL(OH) 3 + 3H 2

[0041] As shown in [Formula 1], aluminum (AL) reacts with water vapor (H 2 O) at high temperature to generate aluminum hydroxide (AL(OH) 3 ). As a result, the colored opaque aluminum (AL) decreases. Further, under high temperature conditions, a reaction occurs as shown by the chemical formula in the following [Formula 2].

[0042] [Formula 2] 2AL(OH) 3 → AL2O 3 + 3H 2 O

[0043] As shown in [Formula 2], aluminum hydroxide (2AL(OH) 3 ) undergoes a dehydration reaction at high temperatures, generating aluminum oxide (AL 2 O 3 ).

[0044] FIG. 5 is a layer configuration diagram showing the state of the laminated film according to an embodiment of the present invention after retort treatment. Due to reactions such as [Formula 1] and [Formula 2], eventually, as shown in FIG. 5, the erosion of the metal vapor deposition surface reaches the substrate film 53B side of the metal vapor deposition layer 53A. And at the location where the metal vapor deposition layer 53A is eroded, there will be transparent aluminum hydroxide (AL(OH) 3 ) and aluminum oxide (AL 2 O 3 ).

[0045] In this case, in the eroded part, the substrate film 53B of the vapor deposition substrate layer 53 can be visually recognized from the outside transparent substrate layer 51 side without being blocked by the opaque metal vapor deposition layer 53A. For the metal vapor deposition layer 53A in contact with the adhesive layer 52 other than the non-coated adhesive part 52a, there is almost no erosion, and the non-transparent vapor-deposited metal remains as it is. Therefore, when viewed from the outside (transparent substrate layer 51 side), the pattern by the non-coated adhesive part 52a can be recognized.

[0046] FIG. 6 is a front view showing the pouch after retort treatment. For example, a non-coated adhesive part 52a is formed in a pattern of "sterilized" on the laminated film 50A used as the first surface film 1. As a result, the adhesive layer 52 includes a non-coated adhesive part 52a in a predetermined pattern shape for performing a predetermined display of "sterilized". Then, before the retort treatment, as shown in FIG. 3, the display of "sterilized" cannot be seen, but after the retort treatment, as shown in FIG. 6, the display of "sterilized" appears, indicating that it has been retort sterilized. That is, the laminated film 50A has served as a sterilization indicator. In FIG. 6, in order to make it easier to confirm the display of "sterilized", unlike FIG. 3, the storage part 11 is shown by hatching.

[0047] <<Example 1>> First, a printing layer was formed on the inner surface side of a transparent vapor-deposited polyethylene terephthalate (PET) film with a thickness of 12 μm. Then, a pattern of "sterilized" was formed as an adhesive non-coated part by gravure printing on the printing surface side to form an adhesive layer. And an aluminum vapor-deposited nylon (ONY) film with a thickness of 15 μm was laminated so that the aluminum vapor-deposited surface was in contact with the surface of the adhesive layer having the adhesive non-coated part. Subsequently, the nylon base material side surface of the aluminum vapor-deposited nylon (ONY) through the adhesive layer was laminated with an easy peel film with a thickness of 30 μm. As the easy peel film, one containing Mitsui Chemicals Toagosei Co., Ltd.'s TAF-650C as an easily peelable thermosetting resin was adopted.

[0048] Thereby, the first surface film 1, which is a laminated film in which transparent vapor-deposited PET 12 μm / printing layer / adhesive layer (with adhesive non-coated part) / AL vapor-deposited ONY 15 μm / adhesive layer (without adhesive non-coated part) / PR 30 μm are laminated in order, was formed. Both of the two adhesive layers were made of a cured product of an acrylic polyol and an isocyanate compound.

[0049] Also, except that the adhesive layer between the transparent vapor-deposited PET film with a thickness of 12 μm and the AL vapor-deposited ONY film with a thickness of 15 μm was formed by solid printing without an adhesive non-coated part, the second surface film 2 and the bottom surface film 3 were formed in the same manner as the first surface film 1. Both the second surface film 2 and the bottom surface film 3 are laminated films in which transparent vapor-deposited PET 12 μm / printing layer / adhesive layer (without adhesive non-coated part) / AL vapor-deposited ONY 15 μm / adhesive layer (without adhesive non-coated part) / PR 30 μm are laminated in order.

[0050] Thereafter, the bottom film 3 was folded back by the folding portion 3a and sandwiched between the first surface film 1 and the second surface film 2, and heat-sealed to each other to form a first side edge portion seal portion 16, a second side edge portion seal portion 17, a first bottom seal portion 15a, and a second bottom seal portion 15b. Further, curry was filled as the content from the opening on the first edge 4 side, and then the opening 12 on the first edge 4 side was heat-sealed to form a first edge seal portion 14 etc. on the first edge 4 to produce a packaging semi-finished product. That is, a sealed pouch as shown in FIG. 3 was obtained. At this point, when the first surface film 1 was visually inspected, the indication of "sterilized" could not be confirmed as in the case shown in FIG. 3.

[0051] <<Example 2>> The first surface film 1, the second surface film 2, and the bottom film 3 were respectively formed in the same manner as in Example 1, except that the laminated film structure was changed to an aluminum (AL) vapor-deposited PET film with a thickness of 12 μm instead of an aluminum (AL) vapor-deposited nylon (ONY) film with a thickness of 15 μm, and a non-stretched polypropylene (CPP) film with a thickness of 60 μm instead of an easy-peel film with a thickness of 30 μm.

[0052] As a result, a first surface film 1 which is a laminated film in which transparent vapor-deposited PET 12 μm / printing layer / adhesive layer (with non-coated adhesive portion) / AL vapor-deposited PET 12 μm / adhesive layer / CPP 60 μm are laminated in order, and a second surface film 2 which is a laminated film in which transparent vapor-deposited PET 12 μm / printing layer / adhesive layer (without non-coated adhesive portion) / AL vapor-deposited PET 12 μm / adhesive layer / CPP 60 μm are laminated in order, and the bottom film 3 were obtained.

[0053] Using the obtained first surface film 1, second surface film 2, and bottom film 3, a pouch was created in the same manner as in Example 1. Further, curry was filled as the content from the opening 12 on the first edge 4 side, and then the opening 12 on the first edge 4 side was heat-sealed to form an upper first edge seal portion 14 etc. to produce a packaging semi-finished product. At this point, when the first surface film 1 was visually inspected, the indication of "sterilized" could not be confirmed as in the case shown in FIG. 3.

[0054] <<Retort processing>> In Examples 1 and 2, the packaging semi-finished product was subjected to retort processing such as pressure heating sterilization treatment at a temperature of 120°C and a pressure of 100 to 300 kPa (kilopascal) for about 20 to 60 minutes, and a retort-packaged food with the contents sealed in the pouch was produced. FIG. 6 is a front view showing the pouch after the retort processing. Then, when the first surface film 1 of the packaged food was visually inspected, the characters "sterilized" could be confirmed in the same manner as shown in FIG. 6.

[0055] As described above, the preferred embodiments of the present invention have been described. However, the present invention is not limited to the above embodiments and various modifications are possible. For example, in the above embodiment, the sterilized indication is made only on the first surface film, but it is also possible to make it only on the second surface film or the bottom surface film. That is, it is also possible to use the laminated film having a display function by heat for the second surface film or the bottom surface film. Further, it is possible to use the laminated film having a display function by heat for any two of the first surface film, the second surface film, and the bottom surface film, or for all of the first surface film, the second surface film, and the bottom surface film, and make the sterilized indication on two surfaces or all surfaces.

[0056] Also, in the above embodiment, the first surface film 1, the second surface film 2, and the bottom surface film 3 are configured by three laminated films, but they may be configured by two or one laminated film. For example, the pouch may be configured using one laminated film in which the first surface film, the bottom surface film, and the second surface film are connected in series, or the pouch may be configured using two laminated films in total, which are composed of a laminated film in which the first surface film, the second surface film, and the bottom surface film are connected in series. In this case, the sterilized indication may be made on only one surface, or may be made on two or more surfaces.

[0057] In addition, in the above-described embodiment, the standing pouch having the first surface film, the second surface film, the bottom surface film, and the bottom gusset portion is used. However, a so-called flat pouch having no bottom surface film and consisting only of the first surface film and the second surface film may be used. Further, pouch packaging bags having various forms such as a four-side seal type, a gusset type, a corner bottom type, a pillow type, and others can be manufactured.

Explanation of Signs

[0058] 1 ··· First surface film 2 ··· Second surface film 3 ··· Bottom surface film 4 ··· First edge 5 ··· Second edge 6 ··· First side edge 7 ··· Second side edge 9 ··· Bottom gusset portion 11 ··· Accommodation portion 12 ··· Opening 14 ··· First edge seal portion 14a ··· First edge seal planned portion 15 ··· Bottom seal portion 15a ··· First bottom seal portion 15b ··· Second bottom seal portion 16 ··· First side edge seal portion 17 ··· Second side edge seal portion 18 ··· Opening start means 19 ··· Easy opening line 50A ··· Laminated film 50B ··· Laminated film 51 ··· Transparent base material layer 52 ··· Adhesive layer 52a ··· Adhesive non-coated portion 53 ··· Vapor deposition base material layer 53A ··· Metal vapor deposition layer 53B ··· Base material film 55 ··· Adhesive layer 56 ··· Sealant layer L1 ··· Distance from the folding portion 3a to the second edge 5 of the pouch W1 ··· Seal widths of the first side edge seal portion 16 and the second side edge seal portion 17

Claims

1. A transparent substrate layer, an adhesive layer, an opaque vapor deposition substrate layer, and a sealant layer are laminated in this order, wherein a metal vapor deposition layer is disposed on the side of the vapor deposition substrate layer that contacts the adhesive layer, the metal contained in the metal vapor deposition layer is aluminum, and the adhesive layer is provided with an adhesive non-coated portion in a predetermined pattern for performing a predetermined display, the laminated film.

2. The laminated film according to Claim 1, wherein the transparent substrate layer is a transparent vapor deposition film obtained by vapor-depositing a metal oxide or an inorganic oxide on a transparent film substrate.

3. A pouch having at least a first surface film and a second surface film, and having a storage portion between the first surface film and the second surface film, the pouch having a first edge and a second edge facing the first edge, and a first side edge and a second side edge extending between the first edge and the second edge, wherein at least one of the films defining the storage portion is composed of a laminated film having, in order from the outside, a transparent substrate layer, an adhesive layer, an opaque vapor deposition substrate layer, and a sealant layer, the vapor deposition substrate layer has a metal vapor deposition layer disposed on the side that contacts the adhesive layer, the metal contained in the metal vapor deposition layer is aluminum, and the adhesive layer is provided with an adhesive non-coated portion in a predetermined pattern for performing a predetermined display, the pouch.

4. The pouch according to Claim 3, wherein the transparent substrate layer is a transparent vapor deposition film obtained by vapor-depositing a metal oxide or an inorganic oxide on a transparent film substrate.

Images