JP6010977B2 - Vapor vent cover and sealed container using the same - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a lid that can be heated in a microwave oven in a sealed container that stores contents such as food and beverages, and a sealed container using the same. In particular, the present invention relates to a lid member having a vapor venting function.

  Conventionally, when cooking retort food, frozen food, beverages, etc., containers for microwave cooking that can be heated as they are are widely used. However, when a sealed container containing moisture-containing objects is heated with a microwave oven or the like, the moisture contained in the objects becomes vapor, so that the container is damaged due to an increase in the internal pressure of the container and the heated contents are scattered. In addition, there is a risk that the inside of the microwave oven will be soiled and there will be dangers such as burns.

  For this reason, when heating a sealed container that contains solids containing moisture, it is necessary to open the container by partially removing the lid before heating. Is troublesome and has the disadvantage of impairing convenience. In addition, since steam generated by microwave heating is immediately discharged out of the container, the steaming effect of the contents by the steam is reduced, and the taste of the contents is reduced.

  In addition, after a hole is formed in a part of the lid material, it is sealed with a seal or the like to maintain the sealing property, and the same function is achieved by discharging the vapor in the container out of the container by increasing the internal pressure during heating. However, there is a problem that the production cost increases due to an increase in the material of the sealing material and the manufacturing process.

  Therefore, the inner surface of the resin film is made to face each other to form a butt portion, and the peripheral portion of the butt portion is heat-sealed except for one side which is the base of the butt portion, thereby unsealed portions communicating with the inside of the container body. An upper member formed and provided with a steam release seal portion at the butting portion, and a lower member that covers the lower surface of the upper member and has a steam guiding portion that communicates with the inside of the container main body at or near the base portion of the butting portion. There is a proposal of a cover material (Patent Document 1).

  However, this proposal has drawbacks such that the manufacturing process is complicated and the cover material is bulky, so that the filling ability is inferior.

  In addition, there is a proposal in which a half cut is provided from the sealant side of the lid, and steam is discharged from the end of the lid using an interface peeling mechanism between different resins (Patent Document 2).

  There is a problem that it takes time for the steam to escape because the portion of the her cut is formed near the center of the opening of the container body.

  Therefore, there is a need for a sealed container that can be heated in a microwave oven in a state in which the contents are stored, that is, a lid member having a vapor venting function and a sealed container using the same.

WO2007 / 020854 Japanese Patent No. 4,825,587

  The present invention provides a sealed container that can be heated in a microwave oven in a state where the contents are stored, that is, a lid member having a vapor venting function and a sealed container using the same.

  In order to solve the above problems, the inventors have intensively studied and completed the present invention.

The invention according to claim 1 of the present invention is a lid member that is heat-sealed to the peripheral edge of the opening of the container and seals the opening,
The lid material is sequentially laminated with a paper layer / plastic film layer / release layer / adhesive layer / sealant layer,
Consists of a laminate that is peeled between the release layer and the adhesive layer,
The release layer is formed on a part of the peripheral edge of the lid;
The adhesive layer and the sealant layer facing the release layer consists switching inclusive from the sealant layer side, half cut for discharging steam upon heating to the outside of the container is formed by a microwave oven,
It said release layer is a venting lid characterized by dot-like pattern der Rukoto.

The invention according to claim 2 of the present invention, the plastic film layer is a vapor vent closure member according to claim 1, wherein the inorganic oxide is a polyethylene terephthalate film was deposited.

The invention according to claim 3 of the present invention is a sealed container using the vapor vent lid according to claim 1 or 2 .

  In the steam vent cover material of the present invention, the steam when heated in a microwave oven is induced by half-cut, and the interlayer between the release layer and the adhesive layer is peeled off by an increase in internal pressure and the heat of the steam, and the peeled gap It is discharged from the end of the lid through the container. Since the release layer is formed at the peripheral edge of the lid member, it is a lid member that can reliably discharge steam out of the container in a short time as the internal pressure increases. Further, the sealed container using the lid member is a highly convenient sealed container.

According to claim 1 of the present invention, in the vapor vent lid member of the present invention, the release layer is formed on a part of the peripheral portion of the cover member, and the adhesive layer and the sealant layer facing the release layer include a sealant. consists switching inclusive from the layer side, half-cutting for discharging steam upon heating to the outside of the container is formed by a microwave oven. Vapor when heated in a microwave oven is induced by a half cut, and the release layer and the adhesive layer can be reliably peeled off in a short time with an increase in internal pressure and heat of the steam. The generated vapor passes through the gap and is discharged outside the container through the gap while peeling the interlayer between the plastic film layer and the adhesive layer. It is a lid that can discharge steam out of the container reliably and in a short time as the internal pressure increases.

According to claim 1 of the present invention, the peeling layer, by a dot-shaped pattern, floating and by the sealing heat when sealing the lid to the container, the lifting of the occurrence at the time of peeling off the lid member Can be prevented.

According to claim 2 of the present invention, since the plastic film layer is a polyethylene terephthalate film on which an inorganic oxide is deposited, gas barrier properties such as oxygen gas and water vapor can be improved. Deterioration can be suppressed. Further, it is possible to prevent the contents from penetrating into the paper layer through the half cut. Moreover, since aluminum foil is not used at the time of disposal, it also has discardability.

According to a third aspect of the present invention, there is provided a sealed container using the vapor vent cover material according to the first or second aspect. The sealed container using the vapor release lid material of the present invention can be heated in a microwave oven as it is without opening a part of the lid material. It is a highly convenient sealed container. After heating, the lid can be peeled from the container to eat the contents.

It is explanatory drawing which shows an example of a structure of the vapor vent lid | cover material of this invention. It is explanatory drawing which shows an example of the sealed container using the vapor vent lid | cover material of FIG. It is explanatory drawing which shows an example in the state in which the vapor removal lid | cover material of FIG. 1 is heated with the microwave oven. It is explanatory drawing which shows an example of the state by which the sealed container of FIG. 2 is heated with the microwave oven.

  Below, the form for implementing this invention is demonstrated concretely.

  FIG. 1 is an explanatory view showing an example of the configuration of the vapor vent lid member of the present invention. The vapor vent lid 1 is composed of a laminate in which a paper layer 2, a plastic film layer 3, a release layer 4, an adhesive layer 5, and a sealant layer 6 are laminated in order from the upper side. The release layer 4 is formed at a predetermined site that is part of the peripheral edge of the lid 1. A half cut 7 for inducing steam to the adhesive layer and the sealant layer facing the release layer 4 is formed from the sealant layer 6 side to the adhesive layer 5.

  FIG. 2 is an explanatory diagram showing an example of a sealed container using the vapor vent lid member of FIG. This is a sealed container 20 in which the flange portion 11 of the container 10 and the sealant layer 6 are heat-sealed and sealed with a vapor vent lid. The sealed container 20 contains contents (not shown) that are heated in a microwave oven.

  FIG. 3 is an explanatory diagram showing an example of a state in which the vapor vent lid member of FIG. 1 is heated in a microwave oven. In the steam vent lid member 1, the steam is guided from the half-cut 7, and peels between the peeling layer 4 and the adhesive layer 5 due to an increase in internal pressure and heat of the steam. Steam A passes through the separated gap 8. The release layer 4 is a starting point through which the vapor A passes, and the vapor A passes through the plastic film layer 3 and the adhesive layer 5 even at a portion where there is no release layer. The state where the steam A is discharged from the end of the lid 1 is shown.

FIG. 4 is an explanatory diagram illustrating an example of a state in which the sealed container of FIG. 2 is heated in a microwave oven.
When heated in a microwave oven, the internal pressure in the sealed container 20 rises, and the vapor A is derived from the half cut 7 and reaches the release layer 4. The release layer 4 increases the internal pressure in the sealed container 20 and heat of the steam. To peel from the adhesive layer 5 to form a gap 8. The steam A is discharged out of the sealed container 20 from the end of the lid member 1 through the formed gap 8.

  The embodiment of the present invention will be described in more detail.

Examples of the paper layer 2 include art paper, coated paper, high-quality paper, and bleached kraft paper, but are not particularly limited. The paper basis weight is not particularly specified, but a range of 50 to 250 g / m ² is preferable, and a range of 80 to 150 g / m ² is more desirable. Moreover, it can be used by printing a pattern on the surface of paper. Moreover, you may print on the back surface of paper which improves light-shielding property. Further, a film such as polyethylene may be laminated in order to improve the water resistance and moisture resistance of the surface of the paper layer.

  The plastic film layer 3 serves to prevent the contents from entering the paper layer and to provide rigidity as a lid. Polyester films (films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate), polyamide films (films such as nylon-6 and nylon-66), polyvinyl chloride films, polyimide films, and the like can be used.

  The thickness is not particularly specified, but is preferably in the range of 9 to 100 μm, and more preferably in the range of 9 to 25 μm. Further, for example, additives such as an antistatic agent, an ultraviolet absorber, a plasticizer, a lubricant, and a colorant can be added, and can be appropriately added as necessary. In addition, you may use what laminated the printing of the light-shielding property to the inner surface of these plastic films, or the film of a light-shielding material.

  Further, by using a polyethylene terephthalate film having gas barrier properties such as oxygen gas and water vapor as the plastic film layer, the oxidative deterioration of the contents can be suppressed.

  As the polyethylene terephthalate film having gas barrier properties, a polyethylene terephthalate film on which an inorganic oxide is deposited can be used. As the inorganic oxide, silicon oxide, aluminum oxide, magnesium oxide, or the like can be used. As thickness of an inorganic oxide, the range of about 20-100 nm is preferable, and the range of 30-60 nm is more preferable.

  The release layer 4 is made of a release agent containing a polyethylene-based or silicon-based wax component using a polyamide resin, a nitrocellulose resin, a urethane resin, a vinyl chloride vinyl acetate copolymer, or the like as a binder, and includes gravure printing and offset printing. The film is partially applied to the back surface of the plastic film layer by a known printing method such as flexographic printing or silk screen printing. That is, it is formed at a predetermined portion that becomes a part of the peripheral edge of the lid. The release layer can be applied in the form of dots or gradations. A dot-like pattern is particularly preferable. Occurrence of floating due to sealing heat when sealing the lid material to the container and floating when peeling the lid material can be prevented. The coating amount may be appropriately selected depending on the type of release agent.

  As the sealant layer 6, it is desirable to have an excellent low-temperature sealing property, and it is preferable that the seal strength does not change regardless of the change in the sealing temperature. Those capable of stably producing an easy peel are preferred.

  An easy peel property is required for the peeling property between the sealant layer and the container. The type of the sealant layer is not particularly limited, and any of a cohesive peeling type, an interlayer peeling type, and an interface peeling type may be used.

  The cohesive peeling type is a type in which the sealant layer itself cohesively breaks, and can be used as a film using a resin in which a resin such as polypropylene, polyethylene, or polystyrene is mixed. Alternatively, these mixed resins may be applied as a coating solution.

  The delamination type is a method in which a three-layer film is formed by a coextrusion method and is peeled off from the middle of the three-layer film.

  The interfacial peeling type is formed into a film using, for example, a resin in which the mixing ratio of vinyl acetate in the ethylene-vinyl acetate copolymer resin is increased.

As the material for the sealant layer, for example, when the container is a polyethylene resin, the mixed combination of base resin / blending thermoplastic resin is polyethylene resin / ethylene-methacrylic acid copolymer, polyethylene resin / ethylene-vinyl acetate. A combination of a copolymer, a polyethylene resin / ethylene-acrylic acid copolymer, and a polyethylene resin / ethylene-ethyl acrylate copolymer is preferred.

  When the container is a polystyrene resin, the combination of the base resin / the thermoplastic resin for blending may be a combination of ethylene-vinyl acetate copolymer / polybutene resin, polyethylene resin / elastomer / petroleum resin / polybutene resin. preferable.

  When the container is a polypropylene resin, the combination of the base resin / the thermoplastic resin for blending is preferably a combination of polypropylene resin / polystyrene resin or polypropylene resin / polyethylene resin.

  The thickness of the sealant layer is preferably in the range of 15 to 100 μm, more preferably in the range of 20 to 40 μm, considering the sealing strength, easy peel property, and workability.

  The adhesive layer 5 serves to adhere the plastic film layer and the sealant layer. It also has pseudo-adhesive properties with the release layer. As the adhesive layer, a film made of an olefin resin such as polyethylene, polypropylene, or polybutene can be used.

  As a method for forming the adhesive layer, an extrusion lamination method using an olefin-based resin such as polyethylene, polypropylene, or polybutene is preferable. Among them, polyethylene is most easily processed. At this time, in consideration of half-cut processing accuracy, the thickness is preferably in the range of 10 to 50 μm, and more preferably in the range of 15 to 30 μm.

  For example, as the extrusion temperature of polyethylene, 280 ° C. to 340 ° C. is suitable, and when it is lower than 280 ° C., not only the film forming property is inferior, but also the surface oxidation of polyethylene itself is insufficient, causing a decrease in laminate strength. End up. In addition, since the decomposition of the resin proceeds at a temperature higher than 340 ° C., not only uniform processing cannot be performed, but also the laminate strength is reduced. That is, it causes a decrease in peel strength.

  Examples of the adhesion method of the paper layer and the plastic film layer include, for example, a wet lamination method, a dry lamination method, a non-solvent dry lamination method, a hot melt lamination method, an extrusion lamination method, and a sand polylamination using the extrusion lamination method. A known method such as a method can be used.

  The half-cut processing method can be a known method such as a Thomson die, a rotary die, or a laser. A half cut is performed on a predetermined part from the sealant layer side of the laminate, and then the outer shape of the lid member is removed. The outline punching process itself may be performed at the time of filling or after filling, and is not limited.

  Similarly, the outer shape can be cut by a known method such as a Thomson die, a rotary die, or a laser. Furthermore, it becomes easy to peel by providing a tab when removing the outer shape of the lid.

  Examples of the present invention will be described in detail below.

Paper (gravure art paper) with a basis weight of 105 g / m ² and a polyethylene terephthalate film with a thickness of 25 μm on which aluminum oxide is vapor-deposited. And pasted together. The deposition thickness of aluminum oxide is 30 nm.

  Next, on the surface of the polyethylene terephthalate film, a release varnish containing a silicone-based wax component with urethane resin as a binder is patterned by gravure printing so that it becomes a part of the peripheral edge of the lid, and the release layer is patterned into dots. Printed.

  Next, on the polyethylene terephthalate film surface on which the release layer is printed, a polypropylene resin-based sealant layer (film) 30 μm mixed with polypropylene resin / polystyrene resin, and a polyethylene resin layer having a thickness of 15 μm at 320 ° C. by a sand polylaminate method. Extruded and bonded.

  Next, three half-cuts were applied to the polyethylene resin layer and the sealant layer facing the release layer from the sealant layer side, and then a punching process was performed to obtain a lid material.

  Next, using polypropylene resin, a cup shaped container was filled with 150 ml of cone soup, and then heat-sealed with the above lid material to prepare a sealed container.

<Comparative Example 1>
A sealed container was prepared in the same manner as in Example 1 except that the half cut was not performed.

<Evaluation method>
Next, the sealed container of Example 1 and Comparative Example 1 was heated for 150 seconds using a 500 W microwave oven, and the vapor vented state of the sealed container was confirmed. The vapor was discharged from the gap between the release layer and the polyethylene resin layer from the half cut. In addition, the state in which the vapor was not discharged and the cover material was about to burst was marked with “x”.

<Evaluation results>
In Example 1, the vapor was derived from the half cut, and was discharged from the end of the lid member while peeling the release layer and the polyethylene resin. Vapor removal was good. In Comparative Example 1, there was no portion through which the steam could escape, and the lid material was about to burst, which was dangerous.

  The steam release lid of the present invention and a sealed container using the same can be used mainly for foods, that is, for storing solids and liquids containing moisture. Even when heated in a microwave oven, the contents of the lid are not ruptured or the contents are not leaked due to deformation of the container. A steam vent cover material that enables safe steam venting and a sealed container using the same.

DESCRIPTION OF SYMBOLS 1 Vapor cover material 2 Paper layer 3 Plastic film layer 4 Release layer 5 Adhesive layer 6 Sealant layer 7 Half cut 8 Crevice 10 Container 11 Flange part 20 Sealed container A of this invention Steam flow

Claims (3)

A lid that is heat-sealed to the peripheral edge of the opening of the container and seals the opening,
The lid material is sequentially laminated with a paper layer / plastic film layer / release layer / adhesive layer / sealant layer,
Consists of a laminate that is peeled between the release layer and the adhesive layer,
The release layer is formed on a part of the peripheral edge of the lid;
The adhesive layer and the sealant layer facing the release layer consists switching inclusive from the sealant layer side, half cut for discharging steam upon heating to the outside of the container is formed by a microwave oven,
The release layer, venting lid characterized by dot-like pattern der Rukoto. The vapor vent lid according to claim 1, wherein the plastic film layer is a polyethylene terephthalate film on which an inorganic oxide is deposited. Sealed container, characterized in that using a vapor vent cover material according to claim 1 or 2.

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