JP2022038119A - Laminate and package - Google Patents

Abstract

To provide a laminate and a package which are capable of suitably indicating information by using microwave.SOLUTION: A plastic film layer 1, a color-developing layer 2 that generates a color by heat, and a heat generation layer 4 that generates heat by absorbing microwave are laminated one upon another in this order from an outer package side to an inner package side. A situation where the color-developing layer 2 is changed by the heat generation layer 4 that has generated heat by the microwave is visible from the outer package side.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to laminates and packages.

Conventionally, there has been a technique of using the temperature rise to bring out information such as characters. Patent Document 1 discloses a technique in which a display calling attention to the surface of a container appears when the temperature of the container becomes high due to cooking with a microwave oven or the like. Patent Document 2 discloses a technique in which a printed layer on the surface of a container changes due to a high temperature of the container caused by pouring hot water, and a two-dimensional code is displayed.

Japanese Unexamined Patent Publication No. 9-48474 Japanese Unexamined Patent Publication No. 2007-21715

The technique disclosed in each of the above patent documents is a technique for displaying information such as characters when the temperature of the container itself becomes high. In recent years, some containers have been devised so that the temperature of the container itself does not become high when the temperature is raised by using microwaves in a microwave oven. However, there are times when we want to show that the contents are hot, even if the container itself is not hot.

In cooking using microwaves in a microwave oven, the timing of raising the temperature of the contents may differ depending on the characteristics of the contents in the container. However, there are times when you want to show consumers information regardless of the characteristics of the contents.

An object of the present disclosure is to provide a laminate and a package capable of appropriately presenting information using microwaves.

The laminate according to the present disclosure is a laminate for microwave irradiation, and has a plastic film layer, a color-developing layer that develops color by heat, and a heat-generating layer that generates heat by absorbing microwaves, in this order. It is possible to visually recognize how the color-developing layer is changed by the heat-generating layer, which is laminated from the side to the interior side and generated by the microwave, from the exterior side.

A shielding layer that makes it difficult to see the heat-generating layer from the exterior side is arranged between the color-developing layer and the heat-generating layer.

The color-developing layer develops color at a temperature higher than 100 ° C.
A package containing the above laminate,
The laminate is arranged so that the exterior side of the laminate is arranged on the exterior side of the package and the interior side of the laminate is arranged on the interior side of the package.

According to the present disclosure, it is possible to provide a laminate and a package capable of appropriately presenting information using microwaves.

It is sectional drawing of the laminated body before change of Embodiment 1. FIG. It is a front view of the laminated body before change of Embodiment 1. FIG. It is sectional drawing of the laminated body after change of Embodiment 1. FIG. It is a front view of the laminated body after the change of Embodiment 1. FIG. It is sectional drawing of the laminated body before change of Embodiment 2. It is a front view of the laminated body before change of Embodiment 2. It is sectional drawing of the laminated body after the change of Embodiment 2. It is a front view of the laminated body after the change of Embodiment 2. It is sectional drawing of the laminated body before change of Embodiment 3. FIG. It is a front view of the laminated body before change of Embodiment 3. FIG. It is sectional drawing of the laminated body after change of Embodiment 3. FIG. It is a front view of the laminated body after the change of Embodiment 3. FIG. It is sectional drawing of the laminated body before change of Embodiment 4. It is sectional drawing of the laminated body before change of Embodiment 5. FIG. It is sectional drawing of the laminated body before change of Embodiment 6. It is a figure which shows the 1st application example of a laminated body. It is a figure which shows the 2nd application example of a laminated body. It is a figure which shows the 3rd application example of a laminated body. It is a figure which shows the 4th application example of a laminated body. It is a figure which shows the 5th application example of a laminated body. It is a figure which shows the 6th application example of a laminated body.

The laminated body in the present embodiment will be described below with reference to the drawings. When the number, quantity, etc. are referred to in the embodiments described below, the scope of the present disclosure is not necessarily limited to the number, quantity, etc., unless otherwise specified. The same reference number may be assigned to the same part or equivalent part, and duplicate explanations may not be repeated. It is planned from the beginning to use the configurations in the embodiments in appropriate combinations. In the figure, the actual dimensional ratio is not shown, and in order to facilitate the understanding of the structure, some ratios may be shown differently.

[Embodiment 1]
The laminated body 10 of the first embodiment will be described with reference to FIGS. 1 to 4. 1 is a cross-sectional view of the laminated body 10 before the change, FIG. 2 is a front view of the laminated body 10 before the change, FIG. 3 is a cross-sectional view of the laminated body 10 after the change, and FIG. 4 is a laminated body after the change. It is a front view of the body 10.

As shown in FIG. 1, the laminated body 10 is composed of a plurality of layers. The laminated body 10 has a structure in which a plastic film layer 1, a coloring layer 2, a shielding layer 3, and a heat generating layer 4 are laminated from the exterior side to the interior side.

The plastic film layer 1 is a support (support) for the color developing layer 2, the shielding layer 3, and the heat generating layer 4, and is responsible for the strength, rigidity, shrinkage characteristics, etc. of the label, and is composed of a transparent resin film. There is. Here, "transparent" means having transparency to the extent that the appearance of the change in hue of the color-developing layer 2 can be visually recognized from the exterior side. Specifically, the plastic film layer 1 preferably has a haze value of 20% or less (JIS K 7136 compliant, thickness 40 μm conversion), and more preferably a haze value of 10% or less. The plastic film layer 1 is preferably colorless, but may be colored as long as the transparency is not impaired.

The thickness of the plastic film layer 1 is, for example, 5 to 80 μm, preferably 10 to 70 μm. The type of resin forming the plastic film layer 1 can be appropriately selected depending on the required physical properties, application, cost and the like. For example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, poly Vinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polybutylene terephthalate film, polyurethane film, ethylene-vinyl acetate copolymer film and the like are used.

The color-developing layer 2 is made of a colorless or light-colored material that develops color by heating. The color-developing layer 2 is composed of about 0.1 to 5 μm (preferably 0.5 to 1 μm). For the color-developing layer 2, an irreversible heat-sensitive color-developing ink containing a leuco dye and a color developer is preferably used. In this case, the color-developing layer 2 develops color by combining the leuco dye dispersed in the ink by the thermal stimulus and the color developer.

The shielding layer 3 is preferably composed of white ink. The shielding layer 3 is composed of, for example, about 2 μm to 3 μm. The shielding layer 3 makes it difficult to see the black color of the heat generating layer 4, which will be described later, from the plastic film layer 1 side on the exterior side.

The heat generating layer 4 is preferably made of a material containing carbon black. The heat generating layer 4 is composed of, for example, about 0.3 to 2 μm (preferably 0.5 to 1 μm). Examples of carbon black include gas black, acetylene black, oil furnace black, thermal black, channel black, ketjen black, carbon nanotubes and the like.

The laminated body 10 shown in FIG. 1 is a cross section of the laminated body 10 shown in FIG. As shown in FIG. 2, it is preferable that the laminated body 10 is configured so that the position of the coloring portion 10A is different from the surrounding color so that the position of the coloring portion 10A can be confirmed from the front. For example, the color-developing portion 10A is in such a state when the black color of the heat-generating layer 4 due to carbon black is displayed lightly through the shielding layer 3.

The laminated body 10 shown in FIG. 3 is a cross section of the laminated body 10 shown in FIG. The laminated body 10 shown in FIG. 1 is irradiated with microwaves to display a design as shown in FIG. In the laminated body 10 shown in FIG. 3, the heat generating layer 4 that has absorbed microwaves generates heat, and the heat is transmitted to the color developing layer 2 through the shielding layer 3. In the laminate 10, the color-developing layer 2 is printed with a pattern corresponding to the characters "high temperature". In the color-developing layer 2, the portion corresponding to the print pattern of the color-developing layer 2 changes to black due to the reaction between the leuco dye and the color developer. The color-developing portion 10A of the laminated body 10 shown in FIG. 2 is in a state in which the characters “high temperature” as shown in FIG. 4 are displayed by irradiating with microwaves from a state in which nothing is displayed in the front view. ..

The layers other than the plastic film layer 1 are printed layers and cannot maintain their own shape without the plastic film layer 1 as a carrier. The shielding layer 3 is not limited to the white ink. The shielding layer 3 is an ink of any color as long as it suppresses the color of the heat generating layer 4 from being seen through to the exterior side and the difference from the color of the color developing layer 2 after the change is remarkable. May be good. The shielding layer 3 makes it easier to recognize characters and the like when the coloring layer 2 develops color. It is preferable to use white ink, gray ink, and silver ink for the shielding layer 3 because of its high shielding property. When the color-developing layer 2 changes from transparent to black, it is preferable to use white ink for the shielding layer 3 because of its high shielding property and the large difference from black.

[Embodiment 2]
The laminated body 20 of the second embodiment will be described with reference to FIGS. 5 to 8. 5 is a cross-sectional view of the laminated body 20 before the change, FIG. 6 is a front view of the laminated body 20 before the change, FIG. 7 is a cross-sectional view of the laminated body 20 after the change, and FIG. It is a front view of the body 20.

As shown in FIG. 5, the laminated body 20 is composed of a structure in which a plastic film layer 1, a coloring layer 2, a shielding layer 3, a color layer 5, and a heat generating layer 4 are laminated from the exterior side to the interior side. There is. In the laminated body 20 of the second embodiment, the color layer 5 is added to the laminated body 10 of the first embodiment. In the laminated body 10 of the first embodiment, the color-developing layer 2 is printed in a pattern, whereas in the laminated body 20 of the second embodiment, the heat generating layer 4 is printed in a pattern.

The color layer 5 is composed of color ink. The color layer 5 is composed of about 0.3 to 2 μm (preferably 0.5 to 1 μm). The color layer 5 preferably has a color equal to or similar to the color of the heat generating layer 4. For example, when the heat generating layer 4 is made of a material containing carbon black, it is preferable that the color layer 5 is made of a black dye or pigment. The color layer 5 makes it difficult to see the black color of the heat generating layer 4 on which the pattern is printed from the side of the plastic film layer 1 on the exterior side. In particular, when white ink is used for the shielding layer 3, a material containing carbon black is used for the heat generating layer 4, and the heat generating layer 4 is printed in a pattern, the color is equal to or similar to the color of the heat generating layer 4. By arranging the layers 5 as shown in FIG. 5, it is possible to effectively suppress the outer shape of the heat generating layer 4 from being seen through from the exterior side.

The laminated body 20 shown in FIG. 5 is a cross section of the laminated body 20 shown in FIG. As shown in FIG. 6, it is preferable that the laminated body 10 is configured so that the position of the coloring portion 20A is different from the surrounding color so that the position of the coloring portion 20A can be confirmed from the front. For example, the color-developing portion 20A is in such a state when the black color of the color layer 5 is displayed lightly through the shielding layer 3.

The laminated body 20 shown in FIG. 7 is a cross section of the laminated body 20 shown in FIG. The laminated body 20 shown in FIG. 5 is irradiated with microwaves to display a design as shown in FIG. In the laminated body 20 shown in FIG. 7, the heat generating layer 4 that has absorbed microwaves generates heat, and the heat is transmitted to the color developing layer 2 through the color layer 5 and the shielding layer 3. The laminated body 20 is printed with a pattern in which the heat generating layer 4 corresponds to the characters “hit” and the symbol “○ ☆ ◇”.

In the color-developing layer 2, the portion corresponding to the print pattern of the heat-generating layer 4 changes to black due to the reaction between the leuco dye and the color developer. The color-developing portion 20A of the laminated body 20 shown in FIG. 6 is irradiated with microwaves from a state in which nothing is displayed in front view, so that the characters “hit” and “○ ☆ ◇” as shown in FIG. 8 are displayed. The symbol of is displayed.

[Embodiment 3]
The laminated body 30 of the third embodiment will be described with reference to FIGS. 9 to 12. 9 is a cross-sectional view of the laminated body 30 before the change, FIG. 10 is a front view of the laminated body 30 before the change, FIG. 11 is a cross-sectional view of the laminated body 30 after the change, and FIG. 12 is a laminated body after the change. It is a front view of the body 30.

As shown in FIG. 9, the laminated body 30 has a structure in which a plastic film layer 1, a color layer 6, a color developing layer 2, a shielding layer 3, a color layer 5, and a heat generating layer 4 are laminated from the exterior side to the interior side. It is composed of. In the laminated body 30 of the third embodiment, the color layer 5 and the color layer 6 are added to the laminated body 10 of the first embodiment. In the laminated body 10 of the first embodiment, the color-developing layer 2 is printed in a pattern, whereas in the laminated body 30 of the third embodiment, the heat generating layer 4 is printed in a pattern. In the laminated body 30 of the third embodiment, the color layer 6 is also printed in a pattern.

Similar to the second embodiment, the color layer 5 makes it difficult to see the black color of the heat generating layer 4 on which the pattern is printed from the side of the plastic film layer 1 on the exterior side. The color layer 6 is printed with a pattern corresponding to the symbol “◯”. The print pattern of the color layer 6 is visible from the exterior side through the plastic film layer 1.

The laminated body 30 shown in FIG. 9 is a cross section of the laminated body 30 shown in FIG. As shown in FIG. 10, it is preferable that the laminated body 30 is configured so that the position of the coloring portion 30A is different from the surrounding color so that the position of the coloring portion 30A can be confirmed from the front. For example, the color-developing portion 30A is in such a state when the black color of the color layer 5 is displayed lightly through the shielding layer 3. The color-developing unit 30A is in a state in which the symbol “◯” is displayed according to the print pattern of the color layer 6.

The laminated body 30 shown in FIG. 11 is a cross section of the laminated body 30 shown in FIG. 12. The laminated body 30 shown in FIG. 9 is irradiated with microwaves to display a design as shown in FIG. In the laminated body 30 shown in FIG. 11, when the heat generating layer 4 that has absorbed microwaves generates heat, the heat is transmitted to the color developing layer 2 through the color layer 5 and the shielding layer 3. In the laminated body 30, the heat generating layer 4 is printed in a pattern corresponding to the symbol “◯”. In the color-developing layer 2, the portion corresponding to the print pattern of the heat-generating layer 4 changes to black due to the reaction between the leuco dye and the color developer. The color-developing portion 30A of the laminated body 30 shown in FIG. 10 is irradiated with microwaves from a state in which the symbol “◯” is displayed by the print pattern of the color layer 6 in the front view, as shown in FIG. "◎" is displayed inside the "○" symbol.

The color layer 5 and the color layer 6 of the laminate 30 may be the same constituent material or may be different constituent materials. The color layer 6 presents a part of the design that can be visually recognized from the exterior side, and various color inks can be applied. On the other hand, the color layer 5 preferably has a color equal to or similar to the color of the heat generating layer 4. For example, when the heat generating layer 4 is made of a material containing carbon black, it is preferable that the color layer 5 is made of a black dye or pigment. As a result, the color layer 5 can prevent the black color of the heat generating layer 4 on which the pattern is printed from being seen through from the plastic film layer 1 side on the exterior side.

[Embodiment 4]
The laminated body 40 of the fourth embodiment will be described with reference to FIG. FIG. 13 is a cross-sectional view of the laminated body 40 before the change.

As shown in FIG. 13, the laminated body 40 has a structure in which a plastic film layer 1, a coloring layer 2, and a transparent heat generating layer 7 are laminated from the exterior side to the interior side. The laminated body 40 of the fourth embodiment is different from the laminated body 10 of the first embodiment in that the shielding layer 3 does not exist and the heat generating layer 4 is a transparent heat generating layer 7 which is a transparent member. ..

The transparent heat generating layer 7 is composed of a transparent or translucent layer. The transparent heat generating layer 7 is composed of about 1 μm. Examples of the transparent heat generating layer 7 include a layer containing a polythiophene-based conductive polymer.

In the laminated body 40 of FIG. 13, the transparent heat generating layer 7 that has absorbed microwaves generates heat, and the heat is transmitted to the color developing layer 2. In the laminated body 40, information such as characters is printed in a pattern on the coloring layer 2. In the color-developing layer 2, the portion corresponding to the print pattern changes to black due to the reaction between the leuco dye and the color developer. In the laminated body 40 of the fourth embodiment, since the color developing layer 2 and the transparent heat generating layer 7 are transparent, it is not necessary to hide the color of the material by the shielding layer 3, so that the number of materials used can be reduced.

[Embodiment 5]
The laminated body 50 of the fifth embodiment will be described with reference to FIG. FIG. 14 is a cross-sectional view of the laminated body 50 before the change.

As shown in FIG. 14, the laminated body 50 has a plastic film layer 1 as a first layer, a color developing layer 2 and a color layer 8 as a second layer, and a transparent heat generating layer 7 as a third layer from the exterior side to the interior side. It is composed of a laminated structure. The laminated body 40 of the fifth embodiment is different from the laminated body 40 of the fourth embodiment in that the color layer 8 is added to the second layer.

The color layer 8 may be made of the same material as the pigment of the color layer 5 described above, or may be made of a different material. The color layer 8 exhibits a part of the design that can be visually recognized from the exterior side, and various color inks can be applied. The color layer 8 is printed, for example, with a frame pattern that surrounds the print pattern of the color development layer 2.

In the laminated body 50 of FIG. 14, the transparent heat generating layer 7 that has absorbed microwaves generates heat, and the heat is transmitted to the color developing layer 2. In the laminated body 50, information such as characters is printed in a pattern on the color-developing layer 2. In the color-developing layer 2, the portion corresponding to the print pattern changes to black due to the reaction between the leuco dye and the color developer. The laminate 50 can make it easy to understand in which portion the information is displayed before the irradiation of the microwave by printing the frame of the color layer 8.

[Embodiment 6]
The laminated body 60 of the sixth embodiment will be described with reference to FIG. FIG. 15 is a cross-sectional view of the laminated body 60 before the change.

As shown in FIG. 15, the laminated body 60 has a structure in which a plastic film layer 1, a coloring layer 2, a design layer 9, a shielding layer 3, and a heat generating layer 4 are laminated from the exterior side to the interior side. .. The laminated body 60 of the sixth embodiment is different in that the design layer 9 is added to the laminated body 10 of the first embodiment.

The design layer 9 is, for example, a printing layer for displaying a product name, a manufacturer name, a logo mark, various designs, a product description, a barcode, and the like. The design layer 9 contains, for example, a coloring material and a binder resin, and may also contain various additives. The design layer 9 is formed by one print layer containing a color material or by combining two or more print layers containing different color materials.

In the laminate 60 of the sixth embodiment, the design layer 9 is arranged on the interior side of the color-developing layer 2, but the design layer 9 is located immediately inside the plastic film layer 1, that is, the plastic film layer 1 and the color-developing layer 2. It may be placed in between. The design layer 9 may be composed of two or more layers. In the sixth embodiment, the design layer 9 is added to the laminate 10 of the first embodiment, but the design layer 9 is added to each of the laminates of the second to fifth embodiments. Needless to say, it's okay.

[Application example of laminated body]
An application example of the above-mentioned laminated body will be described with reference to FIGS. 16 to 21. 16 is a diagram showing a first application example of the laminated body, FIG. 17 is a diagram showing a second application example of the laminated body, and FIG. 18 is a diagram showing a third application example of the laminated body, FIG. 19; Is a diagram showing a fourth application example of the laminated body, FIG. 20 is a diagram showing a fifth application example of the laminated body, and FIG. 21 is a diagram showing a sixth application example of the laminated body. In each package (shrink label, overlap film, tack seal, pouch container, pillow container, lid) of the first to sixth application examples, the exterior side of the laminate is arranged on the exterior side of the package, and the laminate The interior side of the package is arranged on the interior side of the package.

[First application example]
A first application example of the laminated body will be described with reference to FIG. FIG. 16 is an example in which a laminated body is applied to the shrink label 100.

The shrink label 100 has a heat-shrinkable base material. As shown in FIG. 16, the laminated body 100A is configured as a part of the shrink label 100. A conventionally known resin film can be applied to the base material used for the shrink label 100. The cylindrical shrink label 100 is joined by overlapping the ends with a strip-shaped joint along the axial direction.

The resin of the known resin film is selected from thermoplastic resins such as polyester resin, polyolefin resin, polystyrene resin, polyvinyl chloride resin, polyamide resin, polyimide resin, polyphenylene sulfide resin, and acrylic resin. One kind, or a mixture of two or more kinds is exemplified. It may be a laminated film in which two or more kinds of films are laminated. Of these, it is preferable to use a polyester resin, a polyolefin resin, a polystyrene resin, and a laminate thereof from the viewpoint of shrink characteristics and the like, and it is more preferable to use a polyester resin and a polystyrene resin.

As the polyester-based resin, polyethylene terephthalate (PET) -based resin, poly (ethylene-2,6-naphthalenedicarboxylate), polylactic acid (PLA) and the like can be used. Of these, polyethylene terephthalate (PET) -based resin is preferable. As the PET-based resin, terephthalic acid is used as a dicarboxylic acid component and ethylene glycol is used as a diol component in polyethylene terephthalate (PET); terephthalic acid is used as a dicarboxylic acid component and ethylene glycol is a main component as a diol component. Copolymerized polyester (CHDM copolymerized PET) using 4-cyclohexanedimethanol (CHDM) as a copolymerization component; terephthalic acid as a dicarboxylic acid component, ethylene glycol as a main component, and neopentyl glycol (NPG) as a diol component. Copolymerized polyester used as a copolymerization component (NPG copolymerization PET); A diol-modified PET such as a copolymerized polyester using terephthalic acid as a dicarboxylic acid component, ethylene glycol as a main component as a diol component, and diethylene glycol as a copolymerization component. ; Dicarboxylic acid-modified PET (in the dicarboxylic acid component, modified with terephthalic acid as a main component and isophthalic acid and / or adipic acid) and the like can be mentioned.

Examples of the constituent monomers of the polystyrene-based resin include styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, p-ethylstyrene, p-isobutylstyrene, pt-butylstyrene, chloromethylstyrene and the like. Examples thereof include resins containing one or more of the styrene-based monomers of the above. Specific examples include polystyrene, styrene-butadiene copolymer (SBS), styrene-butadiene-isoprene copolymer (SBIS), and styrene, which are homopolymers of styrene or copolymers of styrene and styrene-based monomers. -Acrylic acid ester copolymer and the like can be mentioned.

Examples of the polyolefin-based resin include polyethylene-based resins such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and metallocene-catalyzed LLDPE (mLLDPE), polypropylene, and polypropylene such as propylene-α-olefin copolymer. Examples thereof include a system resin, an ethylene-vinyl acetate copolymer, and a cyclic olefin resin. In particular, as the polyolefin-based film, a film having a cyclic olefin resin as an outer layer is preferable. For example, it is preferable that the cyclic olefin resin is used as an outer layer and the polyethylene resin or polypropylene resin is used as an inner layer (center layer).

The label substrate is preferably stretched in at least one direction (uniaxial stretching) in order to exhibit good heat shrinkage. The stretching temperature varies depending on the type of resin constituting the film, but is, for example, 70 to 100 ° C. The draw ratio is preferably about 2 to 8 times in the main stretching direction of the film. In order to suppress contraction and expansion in the direction orthogonal to the main stretching direction, stretching (biaxial stretching) may be performed in that direction at a magnification of about 1.01 to 2 times.

The heat shrinkage of the label substrate is 20% or more, preferably 30 to 80%, particularly preferably 40 to 80% with respect to the main stretching direction (heat treatment conditions: hot water at 90 ° C. for 10 seconds). Immersion). With respect to the direction orthogonal to the main stretching direction, it is preferably -3 to 15%, more preferably -1 to 10%, and particularly preferably -1 to 5% (heat treatment conditions: same as above). As the stretching method, a roll method, a tenter method, a tube method, or the like can be used. The shrink label 100 is preferably molded so that the main stretching direction of the label base material is the circumferential direction of the cylinder.

[Second application example]
A second application example of the laminated body will be described with reference to FIG. FIG. 17 is an example in which the laminated body is applied to the overlap film 200.

The base material of the overlap film 200 is heat-shrinkable. The overlap film 200 completely seals the container 201 and the lid material 202 from the outside. The lid material 202 is detachably adhered to the container 201 by a heat seal. The laminated body 200A is arranged at a position on the upper surface of the lid material 202 as a part of the overlap film 200. As the base material used for the overlap film 200, the film of the material shown in the first application example can be used.

[Third application example]
A third application example of the laminated body will be described with reference to FIG. FIG. 18 is an example in which a laminated body is applied to the tack seal 300.

FIG. 18 is a cross-sectional view of the tack seal 300. As shown in FIG. 18, the tack seal 300 has a structure in which a plastic film layer 1, a coloring layer 2, a shielding layer 3, a heat generating layer 4, and an adhesive layer 301 are laminated from the exterior side to the interior side. .. In the tack seal 300, an adhesive layer 301 is added to the laminated body 10 of the first embodiment.

The adhesive layer 301 is printed (coated) using a conventionally known printing machine. Examples of the adhesive used for the adhesive layer 301 include an elastomer type (acrylic rubber, ditryl rubber, urethane rubber, styrene butadiene rubber, etc.), a thermosetting resin type (polyester, polyurethane, epoxy resin, melamine resin, etc.), and the like. Adhesives such as thermoplastic resins (acrylic resins, polyolefins, polyvinyl chlorides, ethylene-vinyl acetate copolymers, etc.) can be used. In particular, it is preferable to use a solvent-type, emulsion-type or hot-melt type pressure-sensitive adhesive having adhesiveness at room temperature.

[Fourth application example]
A fourth application example of the laminated body will be described with reference to FIG. FIG. 19 is an example in which the laminated body is applied to the pouch container 400.

FIG. 19 is a front view of the pouch container 400. As shown in FIG. 19, the laminate 400A is arranged as part of the pouch container 400.

Each sheet constituting the pouch container 400 is usually composed of a resin film. The resin film is required to have basic performance as a package such as impact resistance, abrasion resistance, and heat resistance. The pouch container 400 is sealed by a sealing portion shown by hatching in FIG. Since the sealing portion is usually formed by heat sealing, each sheet is also required to have heat sealing properties. As each sheet, a multi-layer sheet having a base film layer as a plastic film layer and a sealant layer that imparts heat sealability is suitable, and when high gas barrier properties are required, the base film layer and the sealant layer are required. It is preferable to provide a gas barrier layer between the two.

Gas barrier properties may be imparted to the base film layer itself. In this case, the barrier layer is used as the base film layer, and the multi-layer sheet has the barrier layer and the sealant layer. When imparting heat sealability to both sides of the sheet, a single-layer film forming a sealant layer may be used, and in the case of a multi-layer sheet, whether the sheet has two layers of the same type or different types of sealant (at this time, the sealant). One layer of the layer will be formally used as the base film layer), or a sheet having a sealant layer on both sides of the base film layer may be used.

The constituent materials of the base film layer, the sealant layer, and the gas barrier layer are exemplified. Lamination of each of these layers can be performed by a conventional laminating method, for example, dry lamination with an adhesive, thermal lamination in which a heat-adhesive layer is sandwiched and heat-bonded.

Examples of the film constituting the base film layer include polyester (polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyvinylidene terephthalate (PBT), polycarbonate (PC), etc.), polyolefin (polyethylene (PE), polypropylene). (PP), etc.), Polyamide (Nylon-6, Nylon-66, etc.), Polyacrylonitrile (PAN), Polyethylene (PI), Polyvinyl Chloride (PVC), Polyvinylidene Chloride (PVDC), Polymethylmethacrylate (PMMA), And a one-layer or two-layer or more stretched or unstretched film composed of polyether sulfone (PES) or the like can be exemplified. The thickness of the base film layer is, for example, 10 μm to 200 μm, preferably 10 μm to 100 μm.

The film constituting the sealant layer includes low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ethylene-propylene copolymer (EP), unstretched polypropylene (CPP), and biaxially stretched nylon (ON). , Ethethylene-olefin copolymer, ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EMAA), ethylene-vinyl acetate copolymer (EVA), etc. Can be exemplified by a stretched or unstretched film. The thickness of the sealant layer is, for example, 20 μm to 200 μm, preferably 30 μm to 180 μm.

The gas barrier layer may be a metal thin film such as aluminum, a resin film such as vinylidene chloride (PVDC) or an ethylene-vinyl alcohol copolymer (EVOH), or an arbitrary synthetic resin film (for example, a base film layer). ), An example is a film obtained by depositing (or sputtering) an inorganic oxide such as aluminum, aluminum oxide or silica.

The laminated body 400A is arranged in the seal portion of the pouch container 400. The object to be contained in the pouch container 400 is irradiated with microwaves to generate steam while raising the temperature. A typical example is food, but it may be non-food. Examples of the contained object include a solid substance, a semi-solid substance, a liquid substance and the like. Frozen foods are typically mentioned as solids, and refrigerated foods, room temperature preserved foods and the like are mentioned as semi-solids and liquids.

In the pouch container 400, the heat generating layer generates heat in parallel with the generation of steam. As the heat generation layer generates heat, the seal portion located directly below the heat generation layer melts or softens. In the portion where the sealed portion is melted or softened, the sheets can be peeled off from each other with a smaller force than in other portions. That is, the melted or softened portion is peeled off by the pressure of the steam, and accordingly, the steam can be released from the peeled portion. Therefore, according to the pouch container 400, even if the internal pressure of the container rises, the container is not damaged and steam can be effectively removed.

[Fifth application example]
A fifth application example of the laminated body will be described with reference to FIG. FIG. 20 is an example in which the laminated body is applied to the pillow container 500.

FIG. 20 is a perspective view of the pillow container 500. As shown in FIG. 20, the laminated body 500A is configured as a part of the pillow container 500.

The pillow container 500 can be made of the same material as the base film layer, the sealant layer, and the gas barrier layer of the pouch container 400 shown as the fourth application example. In FIG. 20, seal portions are formed at both end portions in the longitudinal direction of the pillow container 500 and the backing portion at the center. The laminated body 500A is arranged near the center of the backing portion of the pillow container 500. The object to be contained in the pillow container 500 is irradiated with microwaves to generate steam while raising the temperature. A typical example is food, but it may be non-food. Examples of the contained object include a solid substance, a semi-solid substance, a liquid substance and the like. Frozen foods are typically mentioned as solids, and refrigerated foods, room temperature preserved foods and the like are mentioned as semi-solids and liquids.

In the pillow container 500, the heat generating layer generates heat in parallel with the generation of steam. As the heat generation layer generates heat, the seal portion located directly below the heat generation layer melts or softens. In the portion where the sealed portion is melted or softened, the sheets can be peeled off from each other with a smaller force than in other portions. That is, the melted or softened portion is peeled off by the pressure of the steam, and accordingly, the steam can be released from the peeled portion. Therefore, according to the pillow container 500, even if the internal pressure of the container rises, the container is not damaged and steam can be effectively removed.

[Sixth application example]
A sixth application example of the laminated body will be described with reference to FIG. 21. FIG. 21 is an example in which the laminated body is applied to the lid body 602 of the container 600.

As shown in FIG. 21, the container 600 for microwave processing includes a container main body 601 and a lid body 602 for sealing the opening of the container main body 601. This container is a container that can be put into a microwave oven with an object to be contained such as food sealed inside.

The container body 601 is a bottomed container having one side open in the axis Z direction, and has a bottom portion, a peripheral wall portion, and a flange portion. The container body 601 may be any as long as it can transmit microwaves and can withstand heating using a microwave oven. Specifically, the container body 601 is made of a polyolefin resin such as polyethylene and polypropylene, an aromatic polyester resin such as polyethylene terephthalate, polyethylene naphthalate and polybutylene terephthalate, and an aliphatic polyester resin such as polylactic acid and polyglycolic acid. It is preferably a molded product made of a resin, a polyamide resin such as nylon, a polycarbonate resin, or a synthetic resin such as a polystyrene resin (including expanded polystyrene).

The lid 602 is a sheet-like laminated body that covers the opening. The lid body 602 has a knob portion 604 and is detachably adhered to the flange portion in the adhesive region 603. This adhesion is possible, for example, by heat-sealing the sealant layer of the lid 602 against the flange portion. The adhesive region 603 shows an annular shape in a plan view from the axis Z direction, but the aspect of the adhesive region 603 is not limited to this. The width of the adhesive region 603 is not particularly limited, but is at least equal to or less than the radial width of the flange portion in terms of configuration.

As shown in FIG. 21, the laminated body 600A is configured as a part of the lid body 602. The lid 602 has a sealant layer that exhibits adhesiveness to the flange portion in the base film layer of the pouch container 400 shown as the fourth application example. The sealant layer of the lid 602 is, for example, a layer containing a thermoplastic resin as a main component. Examples of the thermoplastic resin include low-density polyethylene, high-density polyethylene, polypropylene, polyolefin-based resins such as ethylene-vinyl acetate copolymer, and polyester-based resins.

When the container 600 containing the contained object is cooked in a microwave oven or the like, the lid 602 absorbs microwaves and the heat generating layer of the laminated body 600A generates heat. The object to be contained is one that generates steam while raising the temperature by being irradiated with microwaves. A typical example is food, but it may be non-food. Examples of the contained object include a solid substance, a semi-solid substance, a liquid substance and the like. Frozen foods are typically mentioned as solids, and refrigerated foods, room temperature preserved foods and the like are mentioned as semi-solids and liquids.

In the container 600, the heat generating layer generates heat in parallel with the generation of steam. As the heat generation layer generates heat, the sealant layer (the portion heat-sealed on the flange portion) located directly below the heat generation layer melts or softens. Immediately below means a portion that overlaps with the heat generating layer when the surface of the lid 602 is viewed in a plan view from above in the Z direction of the axis. In the portion where the sealant layer is melted or softened, the lid body 602 can be peeled off from the container body 601 with a smaller force than in other portions. That is, the melted or softened portion is peeled off by the pressure of the steam, and accordingly, the steam can be released from the peeled portion. Therefore, according to the container 600, even if the internal pressure of the container rises, the container can be prevented from being damaged or deformed.

[Action / Effect]
The laminate in the present embodiment is a laminate for microwave irradiation by a microwave oven or the like, and is a plastic film layer 1, a color-developing layer 2 that develops color by heat, and a heat-generating layer that generates heat by absorbing microwaves. 4 is laminated from the exterior side to the interior side in this order, and the appearance of the color-developing layer 2 being changed by the heat generating layer 4 generated by the microwave can be visually recognized from the exterior side.

Since the laminate in the present embodiment is intentionally provided with the heat generating layer 4 that absorbs microwaves, the coloring layer 2 can be colored regardless of the temperature of the container itself or the contents. For example, when the contents become hot, information such as "high temperature danger" can be displayed to call attention, and even if the contents do not become hot or there is no contents, the campaign Information such as contents can be shown firmly.

Since the laminate in the present embodiment is intentionally provided with the heat generating layer 4 that absorbs microwaves, even if the timing of raising the temperature of the contents differs depending on the characteristics of the contents in the container, each content has its own temperature rise. It does not need to be individually designed and is preferable for industrial production.

The laminate in this embodiment is easy to manufacture because each layer is printed on one side of the plastic film layer 1 as a base material. In the laminate in the present embodiment, since the plastic film layer 1 is on the exterior side, the inner print layer can be easily protected.

In the laminated body in the present embodiment, a thick base material or the like is not interposed between the coloring layer 2 and the heat generating layer 4. As described above, in the laminated body of the present embodiment, since the distance between the color-developing layer 2 and the heat-generating layer 4 is short, the heat of the heat-generating layer 4 can be effectively transferred to the color-developing layer 2.

In the laminated body of the present embodiment, it is preferable that the heat generating layer 4 contains carbon black. In the laminated body of the present embodiment, a shielding layer 3 that makes it difficult to see the heat generating layer 4 from the exterior side is arranged between the color developing layer 2 and the heat generating layer 4. The shielding layer 3 can prevent the black color of the heat generating layer 4 from being seen through the transparent plastic film layer 1 and the coloring layer 2 from the exterior side. In particular, the shielding layer 3 can prevent the information from being known in advance when the heat generating layer 4 is printed in a pattern.

The plastic film layer 1 in the present embodiment preferably has shrinkage. The laminate 100A of the shrink label 100 shown in FIG. 16 and the laminate 200A of the overlap film 200 shown in FIG. 17 are suitable for packaging containers and the like because the plastic film layer 1 has shrinkage. ..

The shrink label 100 shown in the first application example is preferably attached to the outer surface of a plastic bottle for beverages. For example, a consumer who has purchased a plastic bottle for a beverage can obtain campaign information or the like that appears on the laminate 100A by heating the shrink label 100 removed from the plastic bottle in a microwave oven. When the bottle for beverage is a bottle that can be heated in a microwave oven, it is also possible to heat the bottle in a microwave oven with the shrink label 100 attached.

It is preferable that the overlap film 200 shown in the second application example is attached to the outer surface of the container of the product for microwave oven (cooking by microwave oven). The overlap film 200 is a package including the laminate so that the exterior side of the laminate is arranged on the exterior side of the package and the interior side of the laminate is arranged on the interior side of the package. Is placed. For example, a consumer who has purchased a range-up product can obtain campaign information or the like that appears on the laminated body 200A by range-up the range-up product with the overlap film 200 attached. Further, when the range-up product has a ventilation port, the overlap film 200 is attached so that the laminated body 200A is arranged at a position overlapping the steam port, so that visibility of where the ventilation port is is visible. Can be improved.

The laminate in the present embodiment may further include a sealant layer on the interior side of the heat generating layer 4, and the plastic film layer 1 may be made of a non-shrinkable material. The laminated body 400A of the pouch container 400 shown in FIG. 19, the laminated body 500A of the pillow container 500 shown in FIG. 20, and the laminated body 600A of the lid 602 used for the container 600 shown in FIG. 21 are provided with a sealant layer. Since the plastic film layer 1 does not have shrinkage, it is suitable for packaging materials that do not need to shrink.

In the pouch container 400 shown in the fourth application example, the pillow container 500 shown in the fifth application example, and the container 600 shown in the sixth application example, the laminate is arranged in the seal portion of the microwave oven product. It is preferable to do so. In these containers, the laminated body is arranged as a package including the laminated body so that the outer side of the laminated body is arranged on the outer side of the package and the inner side of the laminated body is arranged on the inner side of the package. Have been placed. Consumers who have purchased range-up products can obtain campaign information and the like that emerge in the laminate by range-up the packaging such as the pouch container 400, pillow container 500, and container 600, which is effective. Can be de-steamed. In addition, it is also possible to call attention to the part where steam is emitted by the characters or the like appearing on the laminated body.

The laminate composed of the tack seal 300 shown in FIG. 18 is provided with an adhesive layer 301 and is not provided with a sealant layer. In the laminate composed of the tack seal 300, the plastic film layer 1 has no shrinkage. Since the laminated body composed of the tack seal 300 can be adhered to other members by the adhesive layer 301, it is effective when it is desired to notify the contents of the campaign or the like with a microwave oven.

In the laminated body of the present embodiment, since the color-developing layer 2 changes due to the heat generated by the heat-generating layer 4, traces of heating in a microwave oven can be easily left. Therefore, it is possible to prevent elderly people and the like from accidentally heating again.

The laminate 10 shown in FIG. 1 is printed so that the print pattern of the color-developing layer 2 falls within the range of the print area of the heat-generating layer 4. With such a configuration, the laminated body 10 can show the user the information shown by the print pattern of the color-developing layer 2 without omission.

The laminate 20 shown in FIG. 5 is printed so that the print pattern of the heat generating layer 4 falls within the range of the print area of the color developing layer 2. With such a configuration, the laminated body 20 can show the user the information shown by the print pattern of the heat generating layer 4 without omission.

The color-developing layer 2 preferably develops color at a temperature higher than the steam temperature (100 ° C.), more preferably develops a color at a temperature higher than 110 ° C., and particularly preferably develops a color at a temperature higher than 120 ° C. Products made up of laminates are expected to reach high temperatures before they reach consumers. For example, when a shrink product is shrunk, a high-temperature beverage is poured into a container, a product composed of a laminate is placed in a high-temperature vending machine, or the product is sterilized at a high temperature. Conceivable. Even in such a case, if the color-developing layer 2 is configured to develop color at a temperature higher than the steam temperature (100 ° C.), it is possible to prevent the color-developing layer 2 from unintentionally developing color.

It is preferable that the heat generating layer 4 does not contain metal. This is because metal may be inadvertently detected during various quality inspections. The heat generating layer 4 may be made of a material containing metal. As the metal, for example, aluminum may be blended. The heat generating layer 4 may be made of a material containing metal and carbon black.

It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present disclosure is shown by the scope of claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 Plastic film layer, 2 Color development layer, 3 Shielding layer, 4 Heat generation layer, 5, 6, 8 color layer, 7 Transparent heat generation layer, 9 Design layer, 10, 20, 30, 40, 50, 60, 100A, 200A, 400A, 500A, 600A laminate, 10A, 20A, 30A Color development part, 100 shrink label, 200 overlap film, 300 tack seal, 400 pouch container, 500 pillow container, 600 container.

Claims (4)

It is a laminated body for microwave irradiation,
A plastic film layer, a color-developing layer that develops color by heat, and a heat-generating layer that generates heat by absorbing microwaves are laminated from the exterior side to the interior side in this order.
A laminated body in which the appearance of the color-developing layer changing due to the heat-generating layer generated by the microwave can be visually recognized from the exterior side. The laminate according to claim 1, wherein a shielding layer that makes it difficult to see the heat-generating layer from the exterior side is arranged between the color-developing layer and the heat-generating layer. The laminate according to claim 1 or 2, wherein the color-developing layer develops color at a temperature higher than 100 ° C. A package including the laminate according to any one of claims 1 to 3.
A package in which the laminate is arranged so that the exterior side of the laminate is arranged on the exterior side of the package and the interior side of the laminate is arranged on the interior side of the package.

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