WO2012073274A1

WO2012073274A1 - Lid material

Info

Publication number: WO2012073274A1
Application number: PCT/JP2010/006971
Authority: WO
Inventors: 片山　洋; 塩畑　淳史
Original assignee: 共同印刷株式会社
Priority date: 2010-11-30
Filing date: 2010-11-30
Publication date: 2012-06-07
Also published as: RU2011142305A; KR101617904B1; CN102639407A; RU2546487C2; KR20130098445A; CN102639407B

Abstract

A lid material (1) comprises an easy-to-peel laminate sheet in which an outer surface layer (14) and an inner surface layer (15) are peelably laminated, the interface between the two forming the peeling surface; a half cut (4) for a circular opening is formed to a depth reaching from the inner surface side to the peeling surface, and a half cut (5) for detachment, which enables the outer surface layer (14) in the area covering the area in which the half cut (4) for a circular opening has been formed to be peeled away and detached from the outer surface layer (14) in the other area, is formed to a depth reaching from the outer surface side to the peeling surface, wherein the formation depth of the half cut (4) for a circular opening and the half cut (5) for detachment are stabilized. The layer structure comprises, in successive order, a paper layer (8), a polyester layer (9a), an easy-to-peel resin layer (10), a polyester layer (9b), and a sealant layer (12). The polyester layer (9b) adjacent to a barrier layer (11) is laminated on the easy-to-peel resin layer (10) via a roughened surface, and is laminated with high peeling strength without an extrusion laminate using an adhesive layer. It is possible to peel the layers using the interface between the polyester layer (9a) adjacent to the paper layer (8) and the easy-to-peel resin layer (10) as the peeling layer, and the paper layer (8) is hardened by the application of a varnish.

Description

Lid material

The present invention relates to a lid member capable of forming an opening for discharging a liquid before removing the whole and completely opening. More specifically, for example, for instant foods such as fried noodles that are cooked by pouring hot water into a container with a lid, and for cooking boiled foods of vegetables and eggs taken out after draining water It relates to a suitable lid.

Conventionally, as a lid member capable of forming an opening before fully opening, a peelable laminated sheet having a layer structure shown in paragraph [0016] of FIG. 1 and FIGS. 1 (a) and 1 (b) is used. The composition is known. Specifically, a paper layer / polyester layer (PET layer) / easily peelable resin layer / adhesive layer / intermediate layer / sealant layer (conventional example 1) and paper layer / adhesive layer / An easily peelable resin layer / PET layer / intermediate layer / sealant layer (conventional example 2) is known. Conventional Examples 1 and 2 can be peeled using the interface between the PET layer and the easily peelable resin layer as a peeled surface.

JP 2007-320580 A

In the conventional example 1, the paper layer and the PET layer outside the release surface constitute the outer surface layer, and the easily peelable resin layer, the adhesive layer, the intermediate layer, and the sealant layer inside the release surface constitute the inner surface layer. . In Conventional Example 2, the paper layer, the adhesive layer, and the easily peelable resin layer outside the release surface constitute the outer surface layer, and the PET layer, the intermediate layer, and the sealant layer inside the release surface constitute the inner surface layer. Yes.

By the way, in order to make a cover material that can form an opening before fully opening, an annular half cut is formed at a depth reaching the peeling surface from the inner surface side, and this opening half It is necessary to form a separation half-cut having a depth reaching the separation surface from the outer surface side so that the outer surface layer in the region covering the cut formation region can be separated from the outer surface layer in the other region. In Conventional Example 1, it is necessary to form a half-cut for opening at a depth that penetrates the adhesive layer and reaches the peeling surface from the inner surface side, and forms a half-cut for separation from the outer surface side through the paper layer There is a need to. Further, in Conventional Example 2, it is necessary to form a half-cut for separation from the outer surface side through the paper layer and the adhesive layer. By forming the half-cut for opening and the half-cut for separation, the inner part of the half-cut for opening of the inner surface layer is attached to this when the outer surface layer of the region covering the formation region of the half-cut for opening is peeled off. Can be removed to reveal the opening.

However, the adhesive layer is used to extrude the easily peelable resin layer and to obtain good adhesiveness with the easily peelable resin layer when extruding the outer layer and the inner layer from the easily peelable resin layer for sand lamination. And a flexible and elastic synthetic resin layer such as polyethylene. The paper layer is also flexible and elastic. When there are many such flexible and elastic layers, there is a problem in that the depth of the half cut tends to vary when the half cut is formed through the layers. If the depth of the half cut is insufficient, it becomes difficult to separate the aperture lid portion, or the inner portion of the aperture half cut on the inner surface layer cannot be removed. On the other hand, when the depth of the half cut is too deep, the sealing force and strength of the lid member are likely to be insufficient.

An object of the present invention is to make it possible to stabilize the formation depth of the half-cut for opening and the half-cut for separating in the lid member that can form the opening before fully opening.

For the above purpose, the present invention comprises an easily peelable laminated sheet in which an outer surface layer and an inner surface layer are laminated so as to be peelable with the interface between them as a peeling surface, and at a depth reaching the peeling surface from the inner surface side. An annular half-cut for opening is formed, and the outer half of the area covering the formation area of the half-hole for opening is separated from the outer surface layer of the other area and can be peeled off. In the lid formed with a depth reaching the release surface from the side,
From the outer surface side, any one of the PET layers arranged in the order of paper layer / PET layer / easy peelable resin layer / PET layer / barrier layer / sealant layer and sandwiching the easily peelable resin layer is provided. The paper layer is laminated with the easily peelable resin layer through the surface subjected to the roughening treatment, and can be peeled with the interface between the other PET layer and the easily peelable resin layer as a peeled surface. Provides a lid material which is cured by application of varnish.

In the present invention, the instability of the formation depth of the half-cut for separation due to the presence of the paper layer is eliminated by curing the paper layer by applying varnish. Moreover, the destabilization of the formation depth of the half-cut for cutting or the half-cut for opening due to the presence of the adhesive layer on one surface side of the easy-peelable resin layer is on each side of the easy-peelable resin layer. An adhesive layer is used by laminating a PET layer that is laminated on the side opposite to the surface that forms the peeled surface with the PET layer adjacent to the easily peelable resin layer through the surface subjected to the roughening treatment. The problem is solved by firmly laminating the film. According to the present invention, since the formation depths of the separation half cut and the opening half cut are stabilized, the generation rate of defective products can be reduced. In addition, according to the present invention, since the formation of the adhesive layer is unnecessary, the manufacturing process is simpler than the conventional easily peelable laminated sheet, and the manufacturing cost can be reduced.

It is a top view which shows an example of the cover material which concerns on this invention. FIG. 2 is an AA enlarged cross-sectional view in FIG. 1 with an intermediate portion omitted. It is explanatory drawing of the usage example of the cover material which concerns on this invention. FIG. 9 is an enlarged cross-sectional view corresponding to AA of FIG. 1 with the intermediate portion omitted, showing another example of the lid according to the present invention.

Hereinafter, the present invention will be further described with reference to the drawings. In the drawings described below, the same reference numerals denote the same elements.

As shown in FIGS. 1 and 2, the lid member 1 is composed of an easily peelable laminated sheet, and is punched into a necessary lid shape. The lid 1 of this example has a part of a substantially circular peripheral edge extending outward to form an opening tab 2 and a part of the peripheral edge opposite to the opening tab 2 is also outside. The peeling tab 3 is formed extending in the direction. Further, an annular half-cut 4 for opening is formed from the inner surface (surface that becomes the inner side of the package), and a separation half cut 5 is formed from the outer surface (the surface that becomes the outer side of the package). Yes. A peeling half-cut 6 is formed on the base of the peeling tab 3 from the inner surface side.

As shown in FIG. 2, the easily peelable laminated sheet constituting the lid material 1 is, as shown in FIG. The barrier layer 11 and the sealant layer 12 are laminated in this order. In the figure, reference numeral 7 denotes a varnish impregnated layer in which the applied varnish penetrates into the paper layer 8 and is cured. In the easily peelable laminated sheet of this example, the interface between the PET layer 9a adjacent to the paper layer 8 and the easily peelable resin layer 10 can be peeled, and this interface forms a peeled surface 13 at the time of peeling. It has become. That is, the paper layer 8 and the PET layer 9a adjacent to the paper layer 8 form the outer surface layer 14 with the release surface 13 as a boundary, and the easily peelable resin layer 10, the PET layer 9b, the barrier layer 11, and the sealant. The layer 12 constitutes an inner surface layer 15, and the outer surface layer 14 and the inner surface layer 15 are laminated so as to be peelable with the interface between them as a peeling surface 13.

Each layer will be explained.

As the varnish for making the paper layer 8 hard, any of an aqueous varnish, an oily varnish, and an ultraviolet curable varnish can be used. Specifically, acrylic varnish, urethane varnish, nitrified cotton varnish and the like can be used. Among these, nitrified cotton-based varnish is preferable in that moderate hardness can be obtained. Further, the coating amount of the varnish is preferably an amount so that the coating thickness is about 0.5 to 4.0 μm in order to harden the paper layer 8 and give good cutting properties.

As the paper layer 8, for example, general paper such as high-quality paper and coated paper can be used. The paper layer 8 imparts necessary strength and rigidity to the lid member 1 and does not bend greatly when the outer surface layer 14 in the region covering the formation region of the opening half-cut 4 is peeled off from the inner surface layer 15 and rolled up. Thus, the paper is preferably made of paper having a basis weight of 35 to 170 g / m ² . When the outer surface layer 14 is greatly curved during the above-mentioned lifting, the inner portion of the opening half-cut 4 of the inner surface layer 15 is likely to fall off without adhering to the outer surface layer 14.

As the PET layers 9a and 9b, a known PET film having a thickness of 2.5 to 25 μm (a film containing PET as a main component) can be used, but it is preferable to use a PET film as a material. The PET layer 9a on the outer surface layer 14 side is a layer in which the interface with the easily peelable resin layer 10 forms the release surface 13, and the surface wetting tension is 3.5 × 10 ⁻² N / m (35 dyn / cm). ~ 6.0 × 10 ^-2 N / m (60 dyn / cm) or less is preferable and the surface wetting tension is 4.0 × 10 ^-2 N / m (40 dyn / cm) to 5.0 × 10 ^-2 N / m (50 dyn / cm) or less is particularly desirable. When the surface wetting tension is less than 3.5 × 10 ⁻² N / m, the adhesive strength is excessively reduced, and inadvertent peeling is likely to occur. On the other hand, if it exceeds 6.0 × 10 ⁻² N / m, the adhesive force is excessively improved and it is difficult to peel off from the easily peelable resin layer 10. The PET layer 9b on the inner surface layer side 15 is a layer that is bonded to the easily peelable resin layer 10 with a strength that does not easily peel, and is between the PET layer 9b and the easily peelable resin layer 10. The adhesive strength is a required strength by performing a roughening treatment such as a corona discharge treatment on the surface of the PET layer 9b on the easily peelable resin layer 10 side.

The easily peelable resin layer 10 is a resin in which a cyclic olefin copolymer (COC) is mixed with polyolefin at a predetermined ratio. Examples of the polyolefin include polyethylene resin and polypropylene resin, but it is preferable to use low density polyethylene (LDPE). Here, COC refers to the preparation of a catalyst such as a Ziegler catalyst or a metallocene catalyst in a hydrocarbon solvent such as hexane, heptane, octane, cyclohexane, benzene, toluene, xylene, and α-olefin and cyclic olefin. It is a copolymer that can be obtained by: As such a copolymer, there is a trade name “Apel” manufactured by Mitsui Chemicals, Inc. As LDPE, there is a trade name “Suntec” manufactured by Asahi Kasei Chemicals Corporation. The polyolefin preferably has an MFR (Melt Flow Rate) of 1 to 50 (g / min), more preferably 1 to 10 (g / min). Further, the polyolefin preferably has a density of 0.89 to 0.940 (g / cm ³ ). The cyclic olefin copolymer (COC) preferably has an MFR of 1 to 40 (g / min), and more preferably 5 to 25 (g / min).

The easily peelable resin layer 10 can control the interfacial peel strength with the PET layer 9a on the outer surface layer 14 side by changing the mixing ratio of LDPE and COC, so that the interfacial peel strength can be adjusted to a desired value. Is possible. The content of COC in the mixed resin constituting the easily peelable resin layer 10 is preferably 1 to 24% by weight, particularly preferably 5 to 20% by weight. When the content is less than 1%, the peel strength between the PET layer 9a becomes strong and difficult to peel, and when it exceeds 24%, the peel strength is difficult to control. Further, the thickness of the easily peelable resin layer 10 is preferably 10 μm to 30 μm in order to obtain stable peelability with the PET layer 9a and stable adhesiveness with the PET layer 9b.

As the barrier layer 11, a metal foil such as an aluminum foil can be used. A synthetic resin film having a high gas barrier property such as polyvinylidene chloride can also be used.

The sealant layer 12 is a layer for heat-sealing the lid 1 to a container or the like to be sealed with the lid 1 and is selected depending on the material to be sealed. For example, LDPE, linear low density polyethylene (LLDPE) ), Ionomer resins, ethylene-vinyl acetate copolymers, and the like.

The easily peelable laminated sheet described above is obtained by extruding an easily peelable resin between a laminate obtained by dry laminating the paper layer 8 and the PET layer 9a and a laminate obtained by dry laminating the PET layer 9b and the barrier layer. After extrusion sand lamination, it can be easily obtained by forming a sealant layer. The easily peelable laminate sheet is laminated with an adhesive strength that cannot be easily peeled, except that it is easily peeled between the PET layer 9a on the outer surface layer 14 side and the easily peelable resin layer 10. .

When the outer surface layer 14 in the formation region of the hole opening half cut 4 is peeled from the inner surface layer 15, the hole half cut 4 is removed along with the inner portion attached to the outer surface layer 14 to be peeled off. Thus, the opening 16 (see FIG. 3) is formed. The opening half-cut 4 is formed with a depth reaching the peeling surface 13 from the inner surface side. In this example, when forming the half cut 4 for opening, the PET layer 9b on the inner surface layer 15 side and the easily peelable resin layer 10 are firmly bonded without using an adhesive layer. Therefore, a large variation in the formation depth can be prevented.

The shape of the opening half-cut 4 is not particularly limited as long as it is annular, and can be freely selected from circular, oval, rounded rectangle, oval, triangular, quadrilateral, pentagonal and more polygons. However, since it is difficult to cause catching when the inside is extracted, a round shape without an angle, an elliptical shape, a rounded rectangular shape, an oval shape, and the like are preferable. Further, the opening half-cut 4 may be singular or plural, but it is usually preferable to form a plurality of the half-cuts 4 so as to easily discharge the liquid with a size that does not allow the packaged article to flow out.

A separation half-cut 5 is formed across the outer surface layer 14 between the outer surface layer 14 covering the formation region of the opening half-cut 4 and the outer surface layer 14 in other regions. The separation half-cut 5 separates the outer surface layer 14 covering the formation region of the opening half-cut 4 from the outer surface layer 14 in other regions and can be separated from the inner surface layer 15. It is formed with a depth that reaches In this example, the paper layer 8 is cured by application of the varnish when the half cut 5 for separation is formed, and the cutting property of the paper layer 8 is improved. A large variation in the formation depth can be prevented. The separation half-cut 5 is usually formed in a continuous line shape, but can also be formed, for example, in a perforation or an intermittent line shape.

The peeling half-cut 6 is for causing a tensile force to act on the interface between the outer layer 14 and the inner layer 15 when the peeling tab 3 is pulled upward. It is formed from the side with the same depth as the opening half-cut 4.

The peeling tab 3 is for facilitating peeling off the outer surface layer 14 covering the formation region of the opening half-cut 4, and is provided on the outer edge of the outer surface layer 14 covering the formation region of the opening half-cut 4. Yes. Further, the opening tab 2 is for facilitating pulling of the lid member 1 when the entire lid member 1 is peeled off from the object to be sealed, and the outer surface layer 14 (opening 16) covering the formation region of the half-cut 4 for opening. Is provided on the outer edge of the outer surface layer 14 other than the outer surface layer 14) to be peeled off during the formation.

Next, an example of use of the lid 1 according to the present invention will be described with reference to FIG.

As shown in FIG. 3A, the lid member 1 is usually used for sealing the container 17. This sealing is performed by covering the lid 1 on the container 17 with the sealant layer 12 facing the container 17, and heat-sealing the flange part 18 projecting to the periphery of the opening of the container 17.

For example, a case where vegetables and boiled eggs are stored will be further described as an example.

When the contents are taken out, first, as shown in FIG. 3 (b), the peeling tab 3 is pulled upward, and the outer surface layer 14 covering the formation region of the opening half-cut 4 is passed through the peeling half-cut 6. Then, it is separated from the outer surface layer 14 in other regions, and peeled off from the inner surface layer 15 to be removed. When the outer surface layer 14 is peeled off, the inner portion of the opening half-cut 4 of the inner surface layer 15 is removed while adhering to the outer surface layer 14 to form the opening 16. After the opening 16 is formed, the water in the container 17 can be discharged from the opening 16 by tilting the container 17 toward the opening 16. Moreover, the outflow of a to-be-packaged object can be prevented by making the magnitude | size of the opening 16 smaller than the to-be-packaged object.

After discharging the water, as shown in FIG. 3C, the opening tab 2 is pulled upward, the entire lid member 1 is peeled off from the flange portion 18 of the container 17, and the opening of the container 17 is fully opened. Take out the package.

When the object to be packaged is instant fried noodles or the like, first, the opening tab 2 is pulled in the state shown in FIG. 3A to partially open the opening of the container 17 and take out the package such as ingredients and sauces. Then pour the hot water. Then, after a certain period of time, an opening 16 is formed as shown in FIG. 3 (b) and the hot water is cut off, and the opening of the container 17 is fully opened as shown in FIG. Will do.

Next, another example of the lid according to the present invention will be described with reference to FIG.

The lid material 1 ′ in this example can be peeled off at the interface between the easily peelable resin layer 10 and the PET layer 9 b on the inner surface layer side as a peeling surface 13, and the PET layer 9 a on the outer surface layer 14 side can be easily peeled off. 1 except that the surface on the side of the adhesive resin layer 10 is roughened and the easily peelable resin layer 10 is located on the side of the outer surface layer 14. is there. Even if it does in this way, the same profit as the above-mentioned example can be acquired.

Example 1
From the outer surface side, an easily peelable laminated sheet having a layer structure of paper layer / PET layer / easy peelable resin layer / PET layer / aluminum foil / sealant layer is produced, and a lid material is produced from the easily peelable laminate sheet. did. The easily peelable laminated sheet was produced by the following procedure.

First, the paper layer and the PET layer that had been printed and coated and cured with varnish were dry-laminated, and the PET layer and aluminum foil were dry-laminated. After the corona discharge treatment is applied to the surface of the PET layer laminated with the aluminum foil, easy peeling at 340 ° C. between the PET layer laminated with the paper layer and the PET layer laminated with the aluminum foil and subjected to the corona discharge treatment. The resin was extruded and extruded and sand laminated. A sealant was extruded and laminated on the surface of the aluminum foil of the obtained laminate to prepare an easily peelable laminate sheet. The outer surface layer of the easily peelable laminated sheet in this example is a paper layer and a PET layer, the inner surface layer is an easily peelable resin layer, a PET layer, an aluminum foil, and a sealant layer, the PET layer on the paper layer side, and the easily adjacent layer. The interface between the peelable resin layer becomes a peeled surface and can be peeled off.

The material of each layer is as follows.

The paper layer used was a coated paper having a basis weight of 80 g / m ² (thickness 80 μm), printed on the outer surface, and then coated with OP varnish and dried. The OP varnish was applied so that the coating thickness was 1 to 2 μm.

Dry lamination of the paper layer and the PET layer was performed via a dry laminate adhesive applied at 3 g / m ² (thickness 3 μm). The PET layer adjacent to the paper layer was 12 μm thick.

As the easily peelable resin layer, a mixed resin of trade name “Apel” manufactured by Mitsui Chemicals, Inc. and product name “Suntech” manufactured by Asahi Kasei Chemicals Corporation was used, and the thickness was 20 μm.

Dry lamination of the aluminum foil and the PET layer was performed via a dry laminate adhesive applied at 3 g / m ² (thickness 3 μm). The thickness of the aluminum foil was 6.5 μm.

As the sealant layer, a polyethylene-based resin “CMPS” manufactured by Mitsui DuPont Polychemical Co., Ltd. was used and extruded and laminated at 240 ° C.

80 pieces of the lid material were punched out from the above easily peelable laminated sheet. For the obtained lid material, the outer surface layer of the region covering the formation region of the opening half-cut is separated and separated from the outer surface layer of the other region to form the opening, and the peeling state is observed, and the peeling half is formed. The presence of defective paper due to insufficient paper cuts due to insufficient cut in the cuts and insufficient cuts due to insufficient cuts in the half-cut for opening was examined. As a result, there was no cover material that caused paper scraping or poor opening, and the defect occurrence rate was 0%.

Comparative Example 1
Except that the varnish was not applied to the paper layer, 80 lid materials were produced in the same manner as in Example 1, and the same investigation was performed. As a result, paper peeling was observed on 9 out of 80 sheets, and the defect occurrence rate was 11.3%.

1, 1 'Lid 2 Opening Tab 3 Peeling Tab 4 Punching Half Cut 5 Peeling Half Cut 6 Peeling Half Cut 7 Varnish Impregnated Layer 8

Paper Layer

9a, 9b Polyester Layer (PET Layer)
DESCRIPTION OF SYMBOLS 10 Easy peelable resin layer 11 Barrier layer 12 Sealant layer 13 Peeling surface 14 Outer surface layer 15 Inner surface layer 16 Opening 17 Container 18 Flange part

Claims

The outer surface layer and the inner surface layer are composed of an easily peelable laminate sheet that can be peeled off with the interface between them as a peeling surface, and an annular half-cut for opening is formed at a depth reaching the peeling surface from the inner surface side. In addition, the separation half-cut that allows the outer surface layer of the region covering the formation region of the opening half-cut to be separated from the outer surface layer of the other region is peeled off at a depth reaching the separation surface from the outer surface side. In the formed lid,
From the outer surface side, one of the polyester layers laminated in the order of a paper layer / polyester layer / easy peelable resin layer / polyester layer / barrier layer / sealant layer and sandwiching the easy peelable resin layer is The paper layer is laminated with the easily peelable resin layer through the surface subjected to the roughening treatment, and can be peeled with the interface between the other polyester layer and the easily peelable resin layer as a peeled surface. Is a lid material cured by application of varnish.