JP2006123330A - Laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminate in which the interfacial peeling strength cab be adjusted according to applications. <P>SOLUTION: The laminate has, between a surface-nontreated metal layer and an adhesive film, a resin layer consisting of a resin for extrusion lamination which is mixed with a polyolefin and a cyclic olefin copolymer in a predetermined ratio. The interface between the metal layer and the resin layer becomes the peeling face. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a laminate having a resin capable of adjusting the strength of a peeled surface depending on the application.

Conventionally, when laminating an aluminum foil and an adhesive film made of a polyolefin resin, there has been no extrusion laminating resin having an appropriate peel strength at the interface with the aluminum foil. Therefore, for example, a lid material, a pouch for pharmaceuticals, etc., could not be manufactured with a configuration utilizing interfacial peeling between the resin layer and the aluminum foil layer.
As a prior art example, there is a multilayer film including a resin layer in which polyethylene, polypropylene, and polycyclic olefin are mixed (see, for example, Patent Document 1).
JP 2004-106514 A

  However, although the mixed resin of the invention described in Patent Document 1 can suppress fluctuations in seal strength, it is an adhesive between the same resins as the innermost layer (sealant), and another material such as an aluminum foil. The peel strength at the interface cannot be adjusted.

  The present invention has been made in view of the above circumstances. For extrusion lamination, a polyolefin and a cyclic olefin copolymer are mixed at a predetermined ratio between an aluminum foil layer that is not surface-treated and an adhesive film. It aims at providing the laminated body which can adjust interface peel strength according to a use by having a resin layer which consists of resin.

  In order to achieve this object, the invention according to claim 1 is a laminate having a surface layer and a metal layer, and a polyolefin and a cyclic olefin copolymer are provided between the surface layer and the metal layer. It has the resin layer mixed by the predetermined | prescribed ratio, and the interface of a metal layer and a resin layer becomes a peeling surface, It is characterized by the above-mentioned.

  The invention according to claim 2 is characterized in that, in the invention according to claim 1, the surface layer includes a base material and an adhesive film.

  The invention according to claim 3 is the invention according to claim 1 or 2, characterized in that the metal layer has an untreated interface with the resin layer.

  According to a fourth aspect of the invention, in the second aspect of the invention, the adhesive film is made of polyolefin.

  ADVANTAGE OF THE INVENTION According to this invention, the laminated body which can adjust interface peeling strength according to a use is realizable.

  The best mode for carrying out the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a side sectional view schematically showing the configuration of the laminate of this example. As shown in FIG. 1, a base film 1 as an outermost layer, an adhesive film 2 provided on one side of the base film 1, and an extrusion laminating resin provided between the adhesive film 2 and the metal layer 4 3 and the metal layer 4 which is the innermost layer are sequentially laminated.

  Examples of the base material 1 include polypropylene resins, polyamide resins, polyester resins, saponified ethylene-vinyl acetate copolymers, polyvinylidene chloride, polycarbonate and other plastic films or sheets, aluminum, iron, copper, and the like. A metal foil such as an alloy as a main component or a metal plate, cellophane, paper, woven fabric, non-woven fabric, or the like can be used, and a single layer or a single layer or a plurality of layers may be selected and laminated. In consideration of dimensional stability, heat resistance, mechanical strength, printing suitability, etc., it is preferable to use polyethylene terephthalate (PET), biaxially oriented polypropylene (OPP), or nylon (Ny). This base material 1 forms a surface layer together with the adhesive film 2 described later by an adhesion method such as wet lamination, non-solvent lamination, dry lamination, or extrusion lamination.

  The adhesive film 2 is a film that is made of a polyolefin such as polyethylene (PE) or polypropylene (PP), is formed on one side of the base film 1 and adheres to the extrusion laminating resin 3. In addition, as a material, in order to ensure adhesive strength with the resin for extrusion laminating, the same material as the resin used for the resin for extrusion laminating is preferable. Specifically, when mixing a cyclic olefin copolymer and a polyethylene resin as an extrusion laminating resin, use a polyethylene resin as the adhesive film, and when mixing a cyclic olefin copolymer and a polypropylene resin as an extrusion laminating resin, adhere When a polypropylene resin is used as the film, the adhesive film 2 and the extrusion laminating resin 3 can be laminated with sufficient adhesive strength. Further, as the role of the adhesive film 2, in addition to obtaining sufficient adhesive strength between the above-mentioned adhesive film 2 and the extrusion laminate resin, the longitudinal tearability of the cyclic olefin copolymer mixed in the extrusion laminate resin is killed, and the metal layer It has the role of preventing vertical tearing when peeling from the surface.

  The metal layer 4 can be made of a metal foil or metal plate such as aluminum, iron, copper, an alloy containing these as a main component, and preferably has a surface roughness (Ra) of 0.40 μm or less. More preferably, it is desirable to use an aluminum foil having a surface roughness (Ra) of 0.40 μm or less.

  The extrusion laminating resin 3 is a resin that is poured between the surface layer and the aluminum layer 4 when the surface layer composed of the substrate 1 and the adhesive film 2 and the aluminum layer 4 are extruded and laminated. The thickness of the extrusion laminating resin 3 is preferably 20 μm to 40 μm in order to obtain a stable peel property.

  The extrusion laminating resin 3 according to this example 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 is a preparation of a catalyst such as a so-called Ziegler catalyst or metallocene catalyst in a hydrocarbon solvent such as hexane, heptane, octane, cyclohexane, benzene, toluene, xylene, and α-olefin and cyclic olefin. As such a copolymer, there is a trade name “Apel” manufactured by Mitsui Chemicals.

(Experiment)
Next, the interfacial peel strength of the extrusion laminating resin 3 in the laminate of this example will be described based on the experimental results of FIG.

  The resin 3 for extrusion laminating of this example is a mixture of LDPE “Suntech L1850K” (manufactured by Asahi Kasei Chemicals Corporation) as polyolefin and “APL6509” (manufactured by Mitsui Chemicals) as COC. As for the mixing ratio, “APL6509” is blended by 5% with respect to “Suntech L1850K”. In this experiment, PET “Toyobo Ester E5100” (manufactured by Toyobo Co., Ltd.) is used as the base material and LDPE “Suzuron S-201” (manufactured by Aicero Chemical Co., Ltd.) is used as the adhesive film 2 in each mixing ratio. And it peeled from the metal layer 4 of the aluminum foil whose surface roughness is 0.40 micrometer or less at the peeling surface 5, and investigated the interfacial peel strength (easiness of peeling of the adhesive film 2) of the resin 3 for extrusion lamination.

  As shown in FIG. 2, in the resin 3 for extrusion laminating, when L1850K is 95% and APL is 5%, the interfacial peel strength is 1.0 kg, L1850K is 90% and APL is 10%. Interfacial peel strength when 0.9kg, L1850K is 85%, APL is 15% is 0.8kg, L1850K is 80%, APL is 20%, and interfacial peel strength is 0.7kg, L1850K is 75%, APL The interfacial peel strength when L is 25% is 0.6 kg, L1850K is 70%, APL is 30%, the interfacial peel strength is 0.5 kg, L1850K is 65%, and the APL is 35%. The interfacial peel strength when 0.4 kg, L1850K was 60%, and APL was 40% was 0.3 kg. Thus, within the range of this experiment, when the ratio of APL (COC) to L1850K (LDPE) was increased by 5%, the interfacial peel strength decreased by 0.1 kg. Even when EMAA was used instead of COC, a result close to that using COC was obtained.

  As described above, conventionally, the interfacial peel strength at the interface of the metal foil layer located in the intermediate layer of the laminate could not be controlled, but the extrusion laminating resin 3 of this example is a low-density polyethylene (LDPE). ) And the cyclic olefin copolymer (COC) can be changed to control the interfacial peel strength with the metal foil layer, so that the interfacial peel strength can be adjusted according to the application.

  As mentioned above, although the Example of this invention was described, it is not limited to the said Example, A various deformation | transformation is possible in the range which does not deviate from the summary.

  The present invention can be applied to lids and easy-open packaging materials such as foods, beverages, seasonings, cosmetics, and pharmaceuticals.

It is a sectional side view which shows typically the structure of the laminated body which is an Example of this invention. It is a table | surface which shows the compounding ratio and interfacial peel strength of the resin for lamination which concern on the Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base material 2 Adhesive film 3 Resin for extrusion lamination 4 Metal layer 5 Release surface

Claims (4)

A surface layer;
A laminate having a metal layer,
Between the surface layer and the metal layer, a resin layer in which a polyolefin and a cyclic olefin copolymer are mixed at a predetermined ratio,
A laminate comprising an interface between the metal layer and the resin layer serving as a release surface.   The laminate according to claim 1, wherein the surface layer includes a base material and an adhesive film.   The laminate according to claim 1 or 2, wherein the metal layer has a surface roughness of 0.40 µm or less.   The laminate according to claim 2, wherein the adhesive film is made of polyolefin.

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