JP2007284072A - Package body, laminated body therefor, and method of producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a package body which is excellent in unsealability, resealability, and productivity. <P>SOLUTION: The package body 100 includes a laminated body 10 having a sealing resin layer 12, an adhesive resin layer 14, and a gas barrier resin layer 16 in this order, and allowing the adhesive resin layer 14 and the gas barrier resin layer 16 to make direct contact with each other, and an adherend 20 at least partly adhering to the sealing resin layer 12 of the laminated body 10. When the adherend 20 is separated from the laminated body 10, the laminated body 10 is broken to form a broken portion 40, and therefore after the separation, the package body can be resealed via the broken portion 40. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a package, a laminate used therefor, and a method for producing the same. In particular, the present invention relates to a package suitably used for foods, pharmaceuticals or miscellaneous goods.

  Foods and medicines are packaged and stored in thermoformed containers or flexible packaging bags, but gas barrier packaging materials are used to prevent oxidative deterioration of the contents during storage. In addition, after opening the package, it may not be consumed at once, and a packaging material that can be easily sealed again is desired.

  In Patent Document 1, a laminate composed of three layers of heat seal layer / adhesive resin layer / polyolefin layer is manufactured in advance, and this laminated film is bonded to a gas barrier material together with polyvinyl chloride (PVC) or aluminum foil. A material is disclosed. However, the use of ethylene-vinyl alcohol copolymer (EVOH) as a gas barrier material is not disclosed.

  When the laminate disclosed in Patent Document 1 is used as a thermoforming sheet, if a gas barrier layer made of, for example, EVOH is used for the laminate, usually a heat seal layer / adhesive resin layer / polyolefin is used. / Adhesive layer / EVOH layer / adhesive layer / polyolefin layer, and the number of layers to be stacked is increased by the number of adhesive layers. Moreover, in this laminated body, the layer which provides resealability and gas-barrier property is another, and it manufactures in a separate process. Therefore, this laminate has the disadvantages that the apparatus cost is high and the manufacture is difficult, resulting in an increase in manufacturing loss.

  In addition, even when the laminate of Patent Document 1 is bonded to a gas barrier film for flexible packaging, an adhesive layer is always provided on both sides of the gas barrier layer, which increases the number of manufacturing steps, which also increases the manufacturing cost. There was a problem.

  Also, Patent Document 2 discloses a package body of a laminate composed of three layers of heat seal (polyolefin) layer / adhesive layer / base material layer. However, a package in which the gas barrier layer and the seal resin layer are directly bonded to the adhesive resin layer is not disclosed.

JP 2001-10659 A JP 2003-175567 A

This invention is made | formed in view of the above-mentioned problem, and it aims at providing the package body excellent in opening and resealability, and excellent in productivity.
Another object of the present invention is to provide a laminate used for the package.
Another object of the present invention is to provide a method for producing the laminate.

As a result of diligent research, the present inventor has found that the gas barrier layer can be directly laminated on the pressure-sensitive adhesive layer, and further has found that this laminate is excellent in unsealing / resealing properties and completed the present invention. I let you.
According to the present invention, the following packaging bodies and the like are provided.
1. A laminated body in which a sealing resin layer, an adhesive resin layer, and a gas barrier resin layer are provided in this order, and the adhesive resin layer and the gas barrier resin layer are in direct contact with each other, and at least a part is bonded to the sealing resin layer of the laminated body A package that includes a member to be bonded, and that peels off the member to be bonded from the laminated body, breaks the laminated body to form a broken portion, peels off, and then reseals at the broken portion.
2. 2. The package according to 1, wherein the gas barrier resin layer is made of an ethylene-vinyl alcohol copolymer resin.
3. The package according to 1 or 2, wherein the sealing resin layer is made of polyolefin, and the adhesive resin layer contains a rubbery copolymer containing a styrene block and a diene block, a tackifying resin, and a plasticizer.
4). A sealing resin layer, an adhesive resin layer, and a gas barrier resin layer are provided in this order, and the adhesive resin layer and the gas barrier resin layer are in direct contact with each other. When the substrate is peeled, a laminate is formed in which a fracture portion is formed and the gas barrier resin layer or the adhesive resin layer is exposed at the fracture portion.
5). The laminate according to 4, wherein the gas barrier resin layer is made of an ethylene-vinyl alcohol copolymer resin.
6). The laminate according to 4 or 5, wherein the seal resin layer is made of polyolefin, and the adhesive resin layer includes a rubbery copolymer containing a styrene block and a diene block, a tackifying resin, and a plasticizer.
7). The manufacturing method of the laminated body in any one of 4-6 which coextrudes a sealing resin layer, an adhesive resin layer, and a gas barrier resin layer.
8). The method for producing a laminate according to any one of 4 to 6, wherein the seal resin layer and the adhesive resin layer are coextruded and then thermally laminated on the gas barrier resin layer.

According to the present invention, it is possible to provide a package that is excellent in unsealing / resealing properties and excellent in productivity.
According to this invention, the laminated body used for the said package can be provided.
According to this invention, the manufacturing method of the said laminated body can be provided.

The package of the present invention has a seal resin layer, an adhesive resin layer, and a gas barrier resin layer in this order, a laminate in which the adhesive resin layer and the gas barrier resin layer are in direct contact, and at least a part of the laminate seal It includes at least an adhesive member bonded to the resin layer. When the adhesive member is peeled from the laminate, the laminate is broken to form a fracture portion. After peeling, the package can be resealed by putting the layer adhering to the adhesive member into the broken portion.
The package of this invention may be comprised from the container consisting of a laminated body, and the adhesive member used as a lid | cover, and may be comprised from the container consisting of an adhesive member, and the laminated body used as a lid | cover. For example, the laminate and the adhesive member can be opposed to the opening / closing part of the package and sealed.

  The laminate of the present invention has a seal resin layer, an adhesive resin layer, and a gas barrier resin layer in this order, and the adhesive resin layer and the gas barrier resin layer are in direct contact with each other. When the adherend member is bonded to the seal resin layer and the adherend member is peeled off, a fracture portion is formed, and the gas barrier resin layer or the adhesive resin layer is exposed at the fracture portion.

FIG. 1 is a diagram showing an example of the relationship between the laminate of the present invention and a member to be bonded.
In this laminate 10, a sealing resin layer 12, an adhesive resin layer 14, and a gas barrier resin layer 16 are laminated in this order, and the gas barrier resin layer 16 is in direct contact with the adhesive resin layer 14 without an adhesive.
The adherend member 20 is thermally welded to the sealing resin layer 12 of the laminate 10. That is, the bonded member 20 and the laminated body 10 are bonded by the bonding portion 30.

  FIG. 1 shows a state in which the adherend member 20 is pulled and peeled from the laminate 10. As shown in this figure, the sealing resin layer 12 and the adhesive resin layer 14 in the vicinity of the edge 32 of the bonding portion 30 are broken from the laminate 10 while being bonded to the member to be bonded 20 to form a broken portion 40. In the fracture portion 40, the gas barrier resin layer 16 is exposed on the laminate 10. By putting the sealing resin layer 12 and the adhesive resin layer 14 adhered to the adherend member 20 in the fracture portion 40, the adherend member 20 can seal the laminate 10 again.

  Note that the break is not limited to the interface between the gas barrier resin layer and the adhesive resin layer, and may be broken at the interface between the seal resin layer and the adhesive resin layer or in the adhesive resin layer.

  In this laminate, since the gas barrier resin layer is directly bonded to the adhesive resin layer, the laminate structure is simplified, the number of manufacturing steps is reduced, and the manufacturing equipment is inexpensive. In particular, as shown in FIG. 1, when the sealing resin layer and the adhesive resin layer are laminated so as to be in direct contact with each other, the laminated structure is further simplified and the production efficiency is improved. The laminate of the present invention can obtain resealability and gas barrier performance at a time with little modification of equipment.

The laminate 10 and the adherend member 20 of the present invention can be used for an opening / closing part of a package. In that case, since it is opened at the heat seal edge part and a re-adhesion part is formed there, a general sealing machine such as a bag making sealing machine, a cup sealing machine, an impulse sealing machine or the like can be employed as it is.
Moreover, since the adhesive resin layer 14 is not exposed, the laminated body 10 of the present invention is easy to handle because the laminated bodies 10 do not adhere to each other even in a wound state.

The seal resin layer only needs to be a resin that can be sealed, and a heat-sealable resin is particularly preferable, for example, a polyolefin such as polyethylene or polypropylene, amorphous polyethylene terephthalate (A-PET), or the like. The resin used for the sealing resin layer may be used alone or in combination of two or more.
The seal resin layer may contain a modifier such as an ethylene-propylene copolymer and an additive such as a lubricant as long as the characteristics are not impaired.

The thickness of the seal resin layer is usually preferably 20 μm or less because it is easy to break at the seal edge during peeling after sealing. Particularly preferred is 5 μm to 15 μm.
Even when the thickness exceeds 20 μm, the sealing resin layer can be peeled off by cutting the sealing resin layer in advance and sealing it to the end of the laminate. When the sealing resin layer exceeds 20 μm, the pressure resistance on the cut side is strong, and the burst resistance of the package is improved.

  The adhesive resin layer includes a rubbery block copolymer containing a styrene block and a diene block, a tackifying resin, and a plasticizer.

  The rubbery block copolymer containing a styrene block and a diene block also includes a hydrogenated rubbery block copolymer containing a styrene block and a diene block. For example, block copolymer in which polystyrene block and vinyl-polyisoprene block are combined, block copolymer in which polystyrene block and ethylene-propylene block are combined, block copolymer in which polystyrene block and ethylene-butadiene block are combined, polystyrene block And a block copolymer in which an ethylene-ethylene-propylene block is bonded.

  Examples of the tackifying resin include hydrogenated rosin resins, terpene resins, hydrogenated terpene resins, C5 / C6 aliphatic petroleum resins, and alicyclic petroleum resins.

  Examples of the plasticizer include liquid paraffin, process oil (aromatic, naphthenic, or paraffinic petroleum hydrocarbon), synthetic wax, and the like.

The pressure-sensitive adhesive resin layer can be produced by kneading and melting a rubbery block copolymer, a tackifier, a plasticizer, and the like. Preferably, the plasticizer is injected and produced from the middle of the single screw extruder.
When the plasticizer is injected from the middle of the single screw extruder, the cost of the extruder is low, and the adhesive strength can be easily adjusted only by changing the injection amount of the plasticizer.
In addition to the above, the adhesive resin layer can contain an inorganic filler such as talc and calcium carbonate, a foaming agent, a colorant such as titanium oxide, and the like as long as the characteristics are not impaired.

  The thickness of the adhesive resin layer is usually preferably 30 μm or less. When the thickness exceeds 30 μm, only the sealing resin layer is easily broken and resealability can be obtained, but the re-adhesion strength is not proportional to the thickness of the adhesive resin layer, which is uneconomical.

The gas barrier resin layer is made of, for example, ethylene-vinyl alcohol copolymer (EVOH) resin or nylon MXD6. EVOH is preferable, and EVOH having a melting point of 190 ° C. or less suitable for co-extrusion fluidity with the adhesive resin layer is particularly preferable.
When the gas barrier resin layer is EVOH, since the surface hardness of EVOH is high, the heat seal layer and the adhesive resin layer of the film are thinned by the edge of the seal teeth at the time of heat sealing, and the heat seal layer and the adhesive resin layer extend at the time of opening. It peels beautifully without. Further, since the interface of the peeling portion is smooth and glossy EVOH, the peeling is smooth and the exposed surface is also beautiful.
When nylon MXD6 is used as the gas barrier resin layer, amorphous nylon may be included.

  The thickness of the gas barrier resin layer can be appropriately selected depending on the application, but is usually preferably 10 μm or more. If the thickness is less than 10 μm, pinholes may easily occur in the laminate.

As for the manufacturing method of a laminated body, the following are preferably mentioned.
(1) A seal resin layer, an adhesive resin layer, and a gas barrier resin layer are coextruded.
(2) The seal resin layer and the adhesive resin layer are coextruded to thermally laminate the gas barrier resin layer.
The laminate of the present invention is preferably formed by co-extrusion such as a T-die method such as a feed block method or a multi-manifold method and an inflation method such as a tubular multilayer inflation method.
You may use a laminated body as a bag making or a lid | cover material as it is in a package. Further, general thermoforming such as plug assist vacuum forming, plug assist pressure forming, hot plate forming or the like may be performed with the seal resin layer inside the container.

Moreover, a laminated body is not restricted to the said structure, For example, the following each layer can be laminated | stacked and comprised.
(I) Seal resin layer / adhesive resin layer / gas barrier resin layer / adhesive resin layer / base material layer (II) Seal resin layer / adhesive resin layer / gas barrier resin layer / base material layer (III) Seal resin layer / adhesive resin layer / Gas barrier resin layer / Adhesive layer / Base material layer

As resin which comprises the base material layer of (I), polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET) etc. are mentioned, for example.
In the case of (I), even if the heat-sealed surface layer is peeled off, since the gas barrier resin has higher heat resistance and hardness than the seal resin, the adhesive resin layer between the gas barrier resin layer and the base material layer breaks together. There is nothing.
Examples of the resin constituting the base layer (II) include maleic anhydride-modified PP, nylon 6, and modified polyester elastomer (TPEE).
Examples of the resin constituting the base layer (III) include PE, PP, PET, and the like.

The base material layer is composed of polystyrene (PS), Ny (polyamide), PBT (polybutylene terephthalate), and the like in addition to those listed above.
The base material layer may be constituted not only by one layer but also by laminating a plurality of layers depending on the application.

The adhesive layer is made of, for example, an adhesive for dry lamination, an anchor coat agent, a melt adhesive, or the like.
Examples of the adhesive for dry lamination include polyester, polyurethane, polyimine, or polyester polyurethane one-component or two-component adhesives.
Examples of the anchor coating agent include urethane-based, polyurethane-based, polyimine-based, and polyester polyurethane-based one-component or two-component anchor coating agents.
Examples of the melt adhesive include maleic anhydride-modified polypropylene.

The laminate having the above-described configuration can be produced by further laminating a laminate composed of a seal resin layer / adhesive resin layer / gas barrier resin layer, and other laminates and layers by dry lamination, thermal lamination, or other lamination means. Specific examples include the following.
(1) Co-extruded seal resin layer / adhesive resin layer / gas barrier resin layer The gas barrier resin layer of PP / PS / PET / Ny / PBT film / sheet is dry laminated to the gas barrier resin layer (2) seal resin layer / Adhesive resin layer / gas barrier resin layer / adhesive resin layer / PP layer film and sealing resin layer / adhesive resin layer / gas barrier resin layer / adhesive layer / PP layer film, molten PP extruded from T-die, and thermal lamination

  The above laminate may be further laminated with other laminates and sheets with dry lamination, thermal lamination or other lamination means.

Adhesive film is PET / Ny / EVOH / casting polypropylene film (CPP), PET / aluminum foil (AL) / CPP, PET / Ny / EVOH / linear low density polyethylene (L-LDPE), transparent vapor-deposited PET / L-LDPE, Ny / EVOH / L-LDPE, and all other heat-bondable films are included.
This film can be manufactured by a usual method.
The thickness of the film is usually 40 μm to 100 μm, but is not limited thereto.

As a bonding method, for example, heat sealing is performed by a bag making sealer, an impulse sealer or the like.
The adhesive strength is stronger than the adhesive strength between the sealing resin layer and the adhesive resin layer of the laminate or higher than the adhesive strength between the gas barrier resin layer and the adhesive resin layer.

In the laminate of the present invention, a weak portion is broken due to the relative relationship between the bonding strength and the bonding strength between the layers.
The adhesive strength depends on the adhesive conditions such as temperature, pressure, time, etc., the thickness of the seal resin surface, resin selection, etc., and the adhesive strength between the seal resin layer and the adhesive resin layer depends on the blending ratio of the adhesive resin layer, etc. The adhesive strength of the gas barrier resin layer can be adjusted by the blending ratio of the adhesive resin layer, the resin blending of the oxygen gas barrier layer, and the like.
In particular, in the present invention, since the sealing resin layer and the adhesive resin layer of the laminate can be made thin by a co-extrusion method, the film can be easily broken at the adhesive end when peeling.

Hereinafter, an embodiment of a package will be described with reference to the drawings.
FIG. 2 shows a container which is an embodiment of the package of the present invention.
This container 100 is comprised from the container main body 120 which consists of the laminated body 10 shown in FIG. 1, and the cover material 140 which consists of a to-be-adhered film.
The lid member 140 is thermally welded at the flange 122 of the container body 120. That is, the lid member 140 is bonded to the sealing resin layer 12 of the laminate 10 constituting the container body 120 by the bonding portion 30.
When opening the container 100, the lid member 140 is pulled and peeled from the container body 120. FIG. 2 shows the state at this time. As shown in this figure, the sealing resin layer 12 and the adhesive resin layer 14 of the bonding portion 30 are broken from the flange 122 of the container body 120 while being bonded to the lid member 140. The gas barrier resin layer 16 is exposed at the fracture portion 40 of the flange 122.
By adhering the sealing resin layer 12 and the adhesive resin layer 14 adhered to the lid member 140 to the gas barrier resin layer 16 exposed at the fracture portion 40 of the flange 122, the container 100 can be closed again.

  Note that the break is not limited to the interface between the gas barrier resin layer and the adhesive resin layer, and may be broken at the interface between the seal resin layer and the adhesive resin layer or in the adhesive resin layer.

  In addition, you may make a notch | circular cut in the flange part near opening. For example, by adjusting the temperature, pressure, and time of the hot blade, cutting is made until the adhesive resin layer is cut. The outer end portion is thermally bonded with a lid material film from the outer periphery of 1 mm to 2 mm from the cut. Opening is started at the outer end portion, and the lid member is separated at the cut portion while being attached to the seal resin layer and the adhesive resin layer of the seal portion.

[Manufacture of laminates]
The following were used for the laminated body of the present Example.
(1) Seal resin layer: random polypropylene resin (manufactured by Prime Polymer, Prime Polypro F-744NP) (density 0.9 g / cm ³ , MFR = 9 g / 10 min)
(2) Gas barrier resin layer: ethylene-vinyl alcohol copolymer resin (Kuraray Co., Ltd., Eval C109B) (density 1.17 g / cm ³ , MFR = 9 g / 10 min, oxygen permeation amount 0.6 cc.20 μm / m) ^2. day.atm)
(3) Adhesive resin layer: Rubber copolymer hydrogenated product (Kuraray Co., Ltd., Septon 2004) (specific gravity 0.89, MFR = 5 g / 10 min, (230 ° C., load 2.16 kg)) 30% by weight In addition, 40% by weight of C5-aromatic copolymer hydrogenated resin (Idemitsu Kosan Co., Ltd., Imabe P-125) (softening point 125 ° C., density 1.03 g / cm ³ (20 ° C.)) was dry blended. Then, it was introduced from a hopper and melt-kneaded. Plasticizer (Idemitsu Kosan Co., Ltd., Diana Process Oil PW-90) (density 0.8722 g / cm ³ (15 ° C.)) and antioxidant (Ciba Specialty Chemicals Co., Ltd., Irganox 1010) A resin obtained by injecting 3% by weight of the resin into the melt-kneaded material from the middle of the extruder so as to be 30% by weight with respect to the total amount of the adhesive material.

Example 1
The sealing resin, adhesive resin, and gas barrier resin were cast and molded using a 400 mm wide T-die apparatus equipped with a 30 mmφ, 30 mmφ, and 40 mmφ single screw extruder and three types and three layers of feed blocks to produce a laminate. In addition, the extruder of the adhesive resin used the dull image for kneading | mixing to the screw, and the thing of the structure which can inject oil on the way from the intermediate part of a barrel was used.
The thickness of the laminate was 10 μm for the sealing resin layer / 20 μm for the adhesive resin layer / 40 μm for the gas barrier resin layer.

[Evaluation]
A laminate film (PET12 / Ny15 / PP) in which the same kind of resin as the resin constituting the seal resin layer is used as a sealant on the side of the seal resin layer of the obtained laminate is 190 ° C. with a surface pressure of 2 Mpa, PET Heat seal teeth were pressed from the surface, and heat sealing with an area of 50 mm × 50 mm was performed for adhesion. Next, after slitting with a width of 15 mm, the strength was measured when the film was pulled off by a push-pull scale (MX-500N, manufactured by Imada Co., Ltd.) at an angle of 90 °.

  The peel strength was 10 N / 15 mm, and it was smoothly opened at the interface between the adhesive resin layer and the EVOH resin layer. The re-adhesion strength was 4 N / 15 mm, which was considered good.

[Easy opening, re-adhesion, production of gas barrier laminated film]
An easy-open, re-adhesive, and gas barrier laminated film could be produced simply by laminating the coextruded film with a 25 μm stretched PET film by conventional dry lamination. This film could be used as a cover material for a thermoforming container having a polypropylene sealing surface or as a film on one side of a four-side sealed bag.

Example 2
Two types and two layers were coextruded using only two 30 mmφ extruders so that the seal resin layer was 10 μm and the adhesive resin layer was 20 μm. A gas barrier resin layer having a thickness of 40 μm, which has been manufactured in advance using a gas barrier resin, is brought into contact with a metal roll, the adhesive layer side of the coextruded two-layer two-layer molten web is brought into contact with the barrier resin layer, and the opposite seal Extrusion lamination molding was performed while pressing with a pinch roll made of silicone rubber from the resin layer side.

  The obtained laminate was evaluated by the same evaluation method as in Example 1. The peel strength was 10 N / 15 mm, and it was smoothly opened at the interface between the adhesive resin layer and the EVOH resin layer. The re-adhesion strength was 4 N / 15 mm, and the same evaluation result as that obtained in Example 1 was obtained for any evaluation item.

  The package of the present invention can be suitably used as a package for food, medicine, miscellaneous goods and medicine.

It is a figure which shows an example of the relationship between the laminated body of this invention, and a to-be-adhered member. It is a figure which shows an example of embodiment of the package of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Laminated body 12 Seal resin layer 14 Adhesive resin layer 16 Gas barrier resin layer 20 Adhered member 30 Adhesion part 40 Breaking part 100 Container (packaging body)
120 Container body (laminate)
140 Lid (Adhering member)

Claims (8)

A laminate having a sealing resin layer, an adhesive resin layer, and a gas barrier resin layer in this order, and the adhesive resin layer and the gas barrier resin layer are in direct contact with each other;
Including at least a part to be bonded to the sealing resin layer of the laminate,
When the member to be bonded is peeled from the laminate, the laminate is broken to form a fracture portion,
After peeling, a package that can be resealed at the broken portion.   The package according to claim 1, wherein the gas barrier resin layer is made of an ethylene-vinyl alcohol copolymer resin. The sealing resin layer is made of polyolefin;
The package according to claim 1 or 2, wherein the adhesive resin layer contains a rubbery copolymer containing a styrene block and a diene block, a tackifying resin, and a plasticizer. It has a sealing resin layer, an adhesive resin layer, and a gas barrier resin layer in this order,
The adhesive resin layer and the gas barrier resin layer are in direct contact,
A laminate in which a member to be bonded is bonded to the seal resin layer, and when the member to be bonded is peeled, a rupture portion is formed, and the gas barrier resin layer or the adhesive resin layer is exposed to the rupture portion.   The laminate according to claim 4, wherein the gas barrier resin layer is made of an ethylene-vinyl alcohol copolymer resin. The sealing resin layer is made of polyolefin;
The laminate according to claim 4 or 5, wherein the adhesive resin layer comprises a rubbery copolymer containing a styrene block and a diene block, a tackifier resin, and a plasticizer.   The manufacturing method of the laminated body in any one of Claims 4-6 which co-extrudes a sealing resin layer, an adhesion resin layer, and a gas barrier resin layer. The method for producing a laminate according to any one of claims 4 to 6, wherein the seal resin layer and the adhesive resin layer are coextruded and then thermally laminated on the gas barrier resin layer.

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