Adhesive film, method for producing adhesive film, and method for producing adhered structure

Abstract

To provide an adhesive film capable of achieving both adhesiveness to an adherend and dimensional retention of the adhesive film even at a high temperature, a method for producing the adhesive film, and a method for producing an adhesive structure.SOLUTION: An adhesive film 10 includes a cyclic olefin polymer layer as a heat resistance layer 11, and an adhesive layer 12 on at least one surface of the heat resistance layer 11, in which the adhesive layer 12 contains an acid-modified polyolefin polymer, and 3 to 50 parts by weight in total of at least one selected from styrene-based elastomers, C5 to C9 petroleum-based resins, and C9 petroleum-based resins in 100 parts by weight of the adhesive layer. 130.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an adhesive film, a method for producing an adhesive film, and a method for producing an adhesive structure. [Background technology]

[0002] Acid-modified polyolefin resins have been known as materials that adhere to various adherends. For example, Patent Document 1 discloses an adhesive resin composition containing an acid-modified polyolefin resin and a cyclic polyolefin resin.

[0003] Regarding the use of cyclic olefin resins, for example, Patent Document 2 describes that by interposing a layer mainly composed of a polypropylene-based resin and / or a polyethylene-based resin between a cyclic olefin resin layer and a functional resin layer, it is possible to achieve both releasability and adhesion to the functional resin layer. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6809899 [Patent Document 2] Patent No. 6323598 Summary of the Invention [Problem to be solved by the invention]

[0005] Adhesive films that are heated to high temperatures for adhesion are required to have adhesion to the adherend and dimensional retention of the adhesive film. The invention described in Patent Document 1 describes the heat seal strength of packaging films, but does not consider dimensional retention at all. The invention described in Patent Document 2 requires releasability from the functional resin layer, and does not emphasize adhesion to the adherend.

[0006] The present invention has been made in consideration of the above circumstances, and its objective is to provide an adhesive film and a method for manufacturing an adhesive film that can achieve both adhesion to an adherend and dimensional retention of the adhesive film even at high temperatures. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides an adhesive film having a cyclic olefin resin layer as a heat-resistant layer and an adhesive layer on at least one side of the heat-resistant layer, the adhesive layer containing a modified polyolefin resin as an essential component and further containing at least one resin having a styrene structure or a cyclic hydrocarbon structure, and the glass transition temperature of the cyclic olefin resin contained in the cyclic olefin resin layer is 130°C or higher.

[0008] The adhesive layer may contain 3 to 50 parts by weight in total of at least one of the resins having a styrene structure or a cyclic hydrocarbon structure, per 100 parts by weight of the adhesive layer. The modified polyolefin resin of the adhesive layer may be modified with an unsaturated carboxylic acid component, and 100 parts by weight of the modified polyolefin resin may contain 0.01 to 2 parts by weight of the unsaturated carboxylic acid component.

[0009] The modified polyolefin resin may be a modified polyethylene resin or a modified polypropylene resin. The adhesive layer may contain 1 to 15 parts by weight of a thermoplastic elastomer resin in 100 parts by weight of the adhesive layer. The adhesive film may have a second adhesive layer on top of the adhesive layer, which is adhered to an adherend of the adhesive film.

[0010] The present invention also provides a method for manufacturing the adhesive film, which includes the steps of melt-kneading the material for the heat-resistant layer in a melt extruder and forming the heat-resistant layer into a film by extrusion molding, and melt-kneading the material for the adhesive layer in a melt extruder and laminating the adhesive layer on at least one side of the heat-resistant layer by extrusion lamination.

[0011] The present invention also provides a method for manufacturing the adhesive film, which includes a step of melt-kneading the materials for the heat-resistant layer and the adhesive layer in an extruder and simultaneously extruding them to form the heat-resistant layer and the adhesive layer into a film with the adhesive layer laminated on at least one side of the heat-resistant layer.

[0012] The present invention also provides a method for manufacturing the adhesive film, which includes the steps of melting and kneading the material for the heat-resistant layer in a melt extruder and forming the heat-resistant layer into a film by extrusion molding, melting and kneading the material for the adhesive layer in a melt extruder and forming the adhesive layer into a film by extrusion molding, and pressing the adhesive layer with a hot roll to laminate it onto at least one side of the heat-resistant layer. [Effects of the Invention]

[0013] According to the present invention, it is possible to achieve both adhesion to an adherend and dimensional retention of the adhesive film even at high temperatures. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a cross-sectional view showing a first embodiment of an adhesive film. [Figure 2] FIG. 4 is a cross-sectional view showing a second embodiment of the adhesive film. [Figure 3] FIG. 4 is a cross-sectional view showing a third embodiment of the adhesive film. DETAILED DESCRIPTION OF THE INVENTION

[0015] The present invention will be described below based on preferred embodiments.

[0016] As shown in Figures 1 to 3, adhesive films 10, 20, and 30 of the embodiments have an adhesive layer 12 on at least one side of a heat-resistant layer 11. As with the adhesive film 10 shown in Figure 1, the adhesive layer 12 may be on one side of the heat-resistant layer 11. As with the adhesive film 20 shown in Figure 2, the adhesive layer 12 may be on both sides of the heat-resistant layer 11. These adhesive layers 12 may be used to adhere the adhesive films 10 and 20 to an adherend (not shown).

[0017] As in the adhesive film 30 shown in Fig. 3, a second adhesive layer 13 that is adhered to an adherend may be provided on the adhesive layer 12. The second adhesive layer 13 may be laminated on the adhesive layer 12 on at least one side of the heat-resistant layer 11. Although not particularly shown, the adhesive layer 12 and the second adhesive layer 13 may be laminated on both sides of the heat-resistant layer 11, respectively.

[0018] The heat-resistant layer 11 is a cyclic olefin resin layer. The cyclic olefin resin layer contains at least a cyclic olefin resin as an essential component. Examples of the cyclic olefin resin include polymers of various cyclic olefin monomers, copolymers of cyclic olefin monomers with other monomers such as ethylene, hydrogenated products thereof, and copolymers of cyclic olefins with other monomers. The cyclic olefin resin may be a cycloolefin polymer (COP) or a cycloolefin copolymer (COC).

[0019] Cyclic olefin monomers include monocyclic olefins, bicyclic olefins, tricyclic olefins, tetracyclic olefins, pentacyclic olefins, hexacyclic olefins, and the like. Examples of the monocyclic olefin include cyclopentene, cyclohexene, cycloheptene, cyclooctene, cyclopentadiene, and cyclohexadiene. Examples of the bicyclic olefin include norbornene, norbornadiene, methylnorbornene, dimethylnorbornene, ethylnorbornene, chlorinated norbornene, chloromethylnorbornene, trimethylsilylnorbornene, phenylnorbornene, cyanonorbornene, dicyanonorbornene, methoxycarbonylnorbornene, pyridylnorbornene, nadic anhydride, and nadic imide. Examples of tricyclic olefins include dicyclopentadiene, dihydrodicyclopentadiene, and alkyl-, alkenyl-, alkylidene-, and aryl-substituted products thereof. Examples of the tetracyclic olefin include dimethanohexahydronaphthalene, dimethanooctahydronaphthalene, and alkyl, alkenyl, alkylidene, and aryl substituted derivatives thereof. Pentacyclic olefins include tricyclopentadiene and its alkyl, alkenyl, alkylidene, and aryl substituted derivatives. Hexacyclic olefins include hexacycloheptadecene and its alkyl, alkenyl, alkylidene, and aryl substituted derivatives. These cyclic olefin monomers are preferably monomers having at least one norbornene structure. The cyclic olefin monomers may be hydrocarbon-based monomers and may have a functional group such as an ester group.

[0020] The polymerization method and polymerization mechanism of the monomer molecules in the cyclic olefin resin may be ring-opening polymerization or addition polymerization. Furthermore, when multiple types of monomers are used in combination, known methods can be used as the polymerization method and polymerization mechanism. The monomers may be blended together and copolymerized. After some monomers have been polymerized to a certain extent, other monomers may be blended to perform block copolymerization.

[0021] The cyclic olefin resin may contain a monomer other than the cyclic olefin monomer, for example, a monomer unit based on an α-olefin. Examples of α-olefins include ethylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, and 1-octene. The cyclic olefin resin may be an amorphous polymer, and may be a homopolymer of a cyclic olefin monomer, a copolymer of two or more cyclic olefin monomers, or a copolymer of at least one cyclic olefin monomer and at least one α-olefin having 2 to 10 carbon atoms. Two or more cyclic olefin monomers may be used, or two or more monomers other than the cyclic olefin monomer may be used.

[0022] The cyclic olefin resin layer forming the heat-resistant layer 11 preferably contains a cyclic olefin resin having a high glass transition temperature (Tg). Specifically, the Tg of the cyclic olefin resin is preferably 130° C. or higher. The Tg of the cyclic olefin resin can be adjusted by the composition of the monomers copolymerized with the cyclic olefin resin, etc.

[0023] The cyclic olefin resin layer of the heat-resistant layer 11 may contain only a cyclic olefin resin as a resin component. The cyclic olefin resin layer of the heat-resistant layer 11 may contain a resin component other than a cyclic olefin resin. The cyclic olefin resin layer of the heat-resistant layer 11 may contain one or more types of cyclic olefin resin in total at a ratio of 50% by weight or more, or even 70 to 100% by weight. The heat-resistant layer 11 may be formed only from a cyclic olefin resin layer, or a heat-resistant layer made of a cyclic olefin resin layer may be used in combination with another heat-resistant layer.

[0024] When the cyclic olefin resin layer of the heat-resistant layer 11 contains another resin component in addition to the cyclic olefin resin, the other resin component is preferably a resin obtained by polymerizing a monomer having at least one structure of ethylene, styrene, cyclic hydrocarbon, etc. The other resin component may be a resin obtained by copolymerizing at least one monomer selected from a monomer having an ethylene structure, a monomer having a styrene structure, and a monomer having a cyclic hydrocarbon structure, or may be a homopolymer of these monomers.

[0025] Examples of monomers having an ethylene structure include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, butadiene, isoprene, etc. Examples of resins obtained by polymerizing these monomers having an ethylene structure include polyolefins such as polyethylene and polypropylene.

[0026] Examples of monomers having a styrene structure include styrene-based monomers such as styrene, methylstyrene, and vinyltoluene. Examples of resins obtained by polymerizing these monomers having a styrene structure include polystyrene and styrene-based elastomers. Examples of styrene-based elastomers include one or more of styrene-ethylene-propylene-styrene block copolymer (SEPS), styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-isoprene-butadiene-styrene block copolymer (SIBS), styrene-ethylene-butylene-olefin crystalline block copolymer (SEBC), and hydrogenated styrene-butadiene rubber (HSBR).

[0027] The monomer having a cyclic hydrocarbon structure may be the above-mentioned monomer having a styrene structure, an aromatic olefin monomer such as indene, or a cyclic olefin monomer. However, a resin obtained by polymerizing a monomer having a cyclic hydrocarbon structure is a resin other than a cyclic olefin resin. The resin obtained by polymerizing a monomer having a cyclic hydrocarbon structure may be, for example, a C5 to C9 petroleum resin, a C9 petroleum resin, or the like.

[0028] The inclusion of other resin components in the cyclic olefin resin layer can suppress brittleness due to the cyclic olefin resin and improve flexibility. When the heat-resistant layer 11 of the cyclic olefin resin layer contains other resin components, it is preferable that the heat-resistant layer 11 contains 5 to 30 parts by weight of a resin obtained by polymerizing a monomer having at least one of the structures of ethylene, styrene, and cyclic hydrocarbon, per 100 parts by weight of the total amount of the heat-resistant layer 11.

[0029] The adhesive layer 12 contains a modified polyolefin resin as an essential component and further contains at least one resin having a styrene structure or a cyclic hydrocarbon structure. The adhesive layer 12 may be a resin layer adjacent to the cyclic olefin resin layer of the heat-resistant layer 11. The modified polyolefin resin has high adhesiveness and is therefore an essential component for imparting adhesiveness to the adhesive layer 12.

[0030] The modified polyolefin resin used in the adhesive layer 12 may be one or more of acid-modified polyolefin resin, hydroxy-modified polyolefin resin, chlorinated polyolefin resin, etc. Among these, acid-modified polyolefin resin modified with an unsaturated carboxylic acid component is preferred. The modified polyolefin resin of the adhesive layer 12 preferably contains 0.01 to 2 parts by weight of the unsaturated carboxylic acid component per 100 parts by weight of the modified polyolefin resin.

[0031] The unsaturated carboxylic acid component may be a carboxyl group-containing monomer having a free carboxylic acid group, or an acid anhydride group-containing monomer having a latent carboxylic acid group. Examples of the carboxyl group-containing monomer include α,β-unsaturated carboxylic acid monomers such as acrylic acid, methacrylic acid, maleic acid, nadic acid, fumaric acid, itaconic acid, citraconic acid, crotonic acid, isocrotonic acid, tetrahydrophthalic acid, and endo-bicyclo[2.2.1]-5-heptene-2,3-dicarboxylic acid (endic acid). Examples of the acid anhydride group-containing monomer include unsaturated dicarboxylic acid anhydride monomers such as maleic anhydride, nadic acid, itaconic anhydride, citraconic anhydride, and endic acid anhydride. The modified polyolefin resin may be a resin in which one unsaturated carboxylic acid component is copolymerized, or a resin in which two or more unsaturated carboxylic acid components are copolymerized.

[0032] Methods for producing modified polyolefin resins include graft-modifying an unmodified polyolefin resin with a functional group-containing monomer by melt-kneading, and copolymerizing an olefin monomer with a functional group-containing monomer. The functional group-containing monomer is a monomer having a polar functional group other than olefin, such as an unsaturated carboxylic acid component, a hydroxy-substituted olefin, or a chlorinated olefin. At least a portion of the modified polyolefin resin may be an acid-modified polyolefin resin obtained by graft-modifying an unsaturated carboxylic acid component using a radical polymerization initiator. Examples of the radical polymerization initiator include organic peroxides and aliphatic azo compounds.

[0033] Examples of olefin monomers used in modified polyolefin resins include one or more of ethylene, propylene, 1-butene, isobutylene, 1-hexene, 1-octene, α-olefins, etc. The modified polyolefin resin may be a modified polyethylene resin, a modified polypropylene resin, a modified poly-1-butene resin, a modified polyisobutylene resin, etc. Examples of unmodified polyolefin resins used in graft-modifying modified polyolefins include polyethylene, polypropylene, poly-1-butene, polyisobutylene, random copolymers of propylene and ethylene or α-olefins, block copolymers of propylene and ethylene or α-olefins, etc.

[0034] The modified polyethylene resin used in the adhesive layer 12 is preferably a resin obtained by copolymerizing 50 parts by weight or more of ethylene with 100 parts by weight of the modified polyethylene resin. The modified polyethylene resin is copolymerized with a functional group-containing monomer such as an unsaturated carboxylic acid component. Furthermore, the modified polyethylene resin may be copolymerized with an olefin monomer other than ethylene, such as propylene, 1-butene, 1-hexene, or 1-octene.

[0035] The modified polypropylene resin used in the adhesive layer 12 is preferably a resin obtained by copolymerizing 50 parts by weight or more of propylene with 100 parts by weight of the modified polypropylene resin. The modified polypropylene resin is copolymerized with a functional group-containing monomer such as an unsaturated carboxylic acid component. Furthermore, the modified polypropylene resin may be copolymerized with an olefin monomer other than propylene, such as ethylene, 1-butene, 1-hexene, or 1-octene.

[0036] The adhesive layer 12 contains at least one resin having a styrene structure or a cyclic hydrocarbon structure in addition to the modified polyolefin resin. This improves the adhesion between the heat-resistant layer 11 and the adhesive layer 12. The adhesive layer 12 preferably contains 3 to 50 parts by weight of at least one resin having a styrene structure or a cyclic hydrocarbon structure per 100 parts by weight of the total amount of the adhesive layer 12. The adhesive layer 12 preferably contains 50 to 97 parts by weight of the modified polyolefin resin per 100 parts by weight of the total amount of the adhesive layer 12.

[0037] Examples of resins having a styrene structure include copolymers of a monomer having a styrene structure and other monomers. Examples of monomers having a styrene structure include styrene-based monomers such as styrene, methylstyrene, and vinyltoluene. Examples of monomers other than styrene-based monomers include aliphatic olefins such as ethylene, propylene, α-olefins, butadiene, and isoprene. The resin having a styrene structure may be a resin in which unsaturated bonds remaining after polymerization have been reduced or saturated by hydrogenation. The resin having a styrene structure may be a styrene-based elastomer. The proportion of the styrene-based monomer in the resin having a styrene structure may be, for example, 10 to 50% by weight.

[0038] Examples of styrene-based elastomers used in adhesive layer 12 include one or more of styrene-ethylene-propylene-styrene block copolymer (SEPS), styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-isoprene-butadiene-styrene block copolymer (SIBS), styrene-ethylene-butylene-olefin crystalline block copolymer (SEBC), hydrogenated styrene-butadiene rubber (HSBR), etc. In styrene-based elastomers, blocks containing styrene constitute hard blocks, and blocks containing aliphatic olefin constitute soft blocks.

[0039] Resins having a cyclic hydrocarbon structure include copolymers of a monomer having a cyclic hydrocarbon structure with another monomer. The monomer having a cyclic hydrocarbon structure may be a monomer having a styrene structure or a monomer having a norbornene structure, or may be a monomer having an alicyclic hydrocarbon structure or an aromatic hydrocarbon structure. Monomers having a cyclic hydrocarbon structure other than a styrene structure or a norbornene structure include indene, allylbenzene, and cycloolefins. Other monomers not having a cyclic hydrocarbon structure include aliphatic olefins such as ethylene, propylene, α-olefins, butadiene, and isoprene.

[0040] At least a part of the resin having a cyclic hydrocarbon structure may be a resin having a styrene structure. The resin having a cyclic hydrocarbon structure may be a resin not having a styrene structure. At least a part of the resin having a cyclic hydrocarbon structure may be a cyclic olefin resin. The resin having a cyclic hydrocarbon structure may not contain a cyclic olefin resin. The resin having a cyclic hydrocarbon structure may be, for example, a C5 to C9 petroleum resin, a C9 petroleum resin, etc.

[0041] The adhesive layer 12 may contain a thermoplastic elastomer resin. The thermoplastic elastomer resin may be a styrene-based elastomer that also serves as the resin having a styrene structure described above. The thermoplastic elastomer resin may be a resin different from the resin having a styrene structure and the resin having a cyclic hydrocarbon structure described above. For example, the thermoplastic elastomer resin may be an olefin-based elastomer. Examples of olefin-based copolymers that can be used for the olefin-based elastomer include aliphatic olefin copolymers such as propylene-ethylene copolymer, ethylene-1-butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, propylene-ethylene-1-butene copolymer, and propylene-1-butene copolymer.

[0042] When the adhesive layer 12 contains at least one styrene-based elastomer as the resin having a styrene structure, it may further contain a thermoplastic elastomer resin other than the styrene-based elastomer, preferably in an amount of 1 to 15 parts by weight based on 100 parts by weight of the total amount of the adhesive layer 12.

[0043] When a second adhesive layer 13 is laminated on the adhesive layer 12, any desired adhesive resin can be used for the second adhesive layer 13 as long as it can be laminated on the adhesive layer 12. Examples of adhesive resins include, but are not limited to, acid-modified polyolefins, epoxy adhesives, and olefin-based heat sealing agents. The second adhesive layer 13 may contain two or more types of adhesive resins, or may contain a resin component other than the adhesive resin.

[0044] Each layer constituting the adhesive films 10, 20, and 30, i.e., the heat-resistant layer 11, the adhesive layer 12, and the second adhesive layer 13, may contain various additives such as antioxidants, ultraviolet absorbers, antistatic agents, lubricants, and antiblocking agents for desired purposes. Any of the heat-resistant layer 11, the adhesive layer 12, and the second adhesive layer 13 may have a composition that does not contain one or more or all of these additives.

[0045] The method for producing the adhesive films 10, 20, 30 is not particularly limited, but examples include methods for forming or laminating each layer by extrusion molding, inflation molding, thermal lamination, extrusion lamination, dry lamination, etc. For example, when producing the adhesive films 10, 20 having the heat-resistant layer 11 and the adhesive layer 12, the heat-resistant layer 11 may be formed first, the adhesive layer 12 may be formed first, or the heat-resistant layer 11 and the adhesive layer 12 may be formed simultaneously.

[0046] A first example of the manufacturing method includes a step of melt-kneading the material of the heat-resistant layer 11 in a melt extruder and extrusion-molding the heat-resistant layer 11 into a film, and a step of melt-kneading the material of the adhesive layer 12 in a melt extruder and extrusion-laminating the adhesive layer 12 onto at least one side of the heat-resistant layer 11. According to the first example manufacturing method, the heat-resistant layer 11 has higher heat resistance than the adhesive layer 12, making manufacturing easier than when the adhesive layer 12 is first molded and then extrusion-laminated onto the heat-resistant layer 11. Furthermore, the first example makes it easier to adjust the film thickness of each layer than the second example described below. Furthermore, the first example improves adhesion between layers because the adhesive layer 12 is laminated to the heat-resistant layer 11 in a molten state, compared to the third example described below.

[0047] A second example of the manufacturing method includes a process in which the materials for the heat-resistant layer 11 and the adhesive layer 12 are melt-kneaded in an extruder and simultaneously extruded to form a film of the heat-resistant layer 11 and the adhesive layer 12 with the adhesive layer 12 laminated on at least one side of the heat-resistant layer 11. The second example of the manufacturing method requires only one extrusion step, shortening the work compared to the first example described above and the third example described below. Furthermore, because the heat-resistant layer 11 and the adhesive layer 12 are laminated in a molten state, adhesion between the layers is improved.

[0048] A third example of the manufacturing method includes the steps of melt-kneading the material for the heat-resistant layer 11 in a melt extruder and extruding the heat-resistant layer 11 into a film; melt-kneading the material for the adhesive layer 12 in a melt extruder and extruding the adhesive layer 12 into a film; and pressing the adhesive layer 12 onto at least one side of the heat-resistant layer 11 with a hot roll to laminate the layer. According to the third example of the manufacturing method, the heat-resistant layer 11 and the adhesive layer 12 can be molded separately and then laminated in any desired combination as needed, facilitating design changes and manufacturing control. The order of forming the heat-resistant layer 11 into a film and the adhesive layer 12 into a film is not particularly limited, and they can also be performed simultaneously.

[0049] When the heat-resistant layer 11 has adhesive layers 12 on both sides, the adhesive layers 12 on each side may be laminated to the heat-resistant layer 11 by the same method or by different methods. The adhesive layers 12 on both sides may be resin layers with different compositions or thicknesses, or may be resin layers with the same composition or thickness. The thicknesses of the heat-resistant layer 11 and the adhesive layer 12 are not particularly limited, but may be, for example, about 1 to 300 μm for each of the heat-resistant layer 11 and the adhesive layer 12. The thicknesses of the adhesive films 10, 20, and 30 are not particularly limited, but may be, for example, about 10 to 500 μm.

[0050] When manufacturing an adhesive film 30 having a second adhesive layer 13, the adhesive layer 12 may be formed before the second adhesive layer 13, the second adhesive layer 13 may be formed before the adhesive layer 12, or the adhesive layer 12 and the second adhesive layer 13 may be formed simultaneously. The method for forming the second adhesive layer 13 is not particularly limited, and may be the same as the method for forming the adhesive layer 12, or may be a method different from the method for forming the adhesive layer 12. In the first to third examples of the manufacturing method described above, the second adhesive layer 13 may be formed in the same manner as the adhesive layer 12.

[0051] The adherend of the adhesive films 10, 20, 30 is not particularly limited, and examples thereof include various materials such as resin, rubber, metal, glass, and ceramics. Since the adhesive layer 12 contains a modified polyolefin resin as an essential component, it can be suitably adhered to adherends such as metals. Examples of metals include, but are not limited to, iron, copper, aluminum, stainless steel, chromium, and nickel. The surface of the adherend may be a treated surface that has been subjected to a surface treatment such as textured processing or chemical conversion coating.

[0052] The present invention has been described above based on preferred embodiments, but the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the gist of the present invention. [Example]

[0053] The present invention will be specifically described below with reference to examples.

[0054] (Resin used) The following resins were used for the heat-resistant layer and adhesive layer. When showing the resin compositions in Table 1, the compounding ratio in parts by weight is added to the right of the component symbols below. For example, "A-1 100" indicates that 100 parts by weight of A-1 was used.

[0055] "A-1" is a cyclic olefin resin with a Tg of 145°C and an MFR of 10g / 10min (260°C, 2.16kg). "A-2" is a cyclic olefin resin with a Tg of 178°C and an MFR of 1.5g / 10min (260°C, 2.16kg). "A-3" is a cyclic olefin resin with a Tg of 105°C and an MFR of 26g / 10min (260°C, 2.16kg). "B-1" is polyethylene (LLDPE) with a melting point of 120°C.

[0056] "C-1" is an acid-modified polypropylene (PP) with a melting point of 140°C and an MFR of 7.0g / 10min (230°C, 2.16kg). "C-2" is an acid-modified polyethylene (PE) with a melting point of 120°C and an MFR of 6g / 10min (230°C, 2.16kg). "D-1" is a styrene-containing resin (SEBS) with a styrene content of 43% and an MFR of 3.0 g / 10 min (230°C, 2.16 kg). "D-2" is a C9 hydrocarbon resin, which is a copolymer of vinyltoluene and indene.

[0057] (Methods of manufacturing adhesive films of Examples 1 to 7 and Comparative Examples 1 and 2) The resin for the heat-resistant layer and the resin for the adhesive layer were dry-blended in pellet form in a mixer using the compositions shown in Table 1. The resin for the heat-resistant layer was melt-kneaded at 300°C for 2 minutes, and the resin for the adhesive layer was melt-kneaded at 270°C for 2 minutes, and then an adhesive film of the specified thickness was obtained by co-extrusion molding of the two layers. In Table 1, this method of co-extrusion molding of the two layers is designated as "P-1."

[0058] (Method for producing adhesive film of Example 8) The resin for the heat-resistant layer and the resin for the adhesive layer were dry-blended in pellet form in a mixer according to the composition shown in Table 1. The resin for the heat-resistant layer was melt-kneaded at 300°C for 2 minutes, and then extrusion-molded to obtain a film for the heat-resistant layer. Next, the resin for the adhesive layer was melt-kneaded at 270°C for 2 minutes, and then extrusion-laminated onto the film for the heat-resistant layer to obtain an adhesive film of the specified thickness. In Table 1, this extrusion lamination method is designated "P-2."

[0059] (Method for producing adhesive film of Example 9) The resin for the heat-resistant layer and the resin for the adhesive layer were dry-blended in pellet form in a mixer, according to the composition shown in Table 1. The resin for the heat-resistant layer was melt-kneaded at 300°C for 2 minutes, and then extrusion-molded to obtain a film for the heat-resistant layer. Next, the resin for the adhesive layer was melt-kneaded at 270°C for 2 minutes, and then extrusion-molded to obtain a film for the adhesive layer. The resulting film for the heat-resistant layer and the film for the adhesive layer were superimposed and heat-pressed with a heated roll at 270°C to obtain an adhesive film of the specified thickness. In Table 1, this thermal lamination method is designated "P-3."

[0060] (Method for measuring adhesive strength) An adhesive film with a heat-resistant layer thickness of 20 μm, an adhesive layer thickness of 80 μm, and a total thickness of 100 μm was used as the sample. Aluminum foil with a thickness of 50 μm was used as the adherend. These were cut to a size of 50 mm x 50 mm, and the adherend was placed on the sample. The sample was then heated and pressed from the adherend side at a temperature of 170 ° C, a pressure of 0.1 MPa, and a time of 10 seconds. The sample was then cut to a width of 15 mm. The adhesive strength of the sample heated and pressed to the adherend was measured using a tensile tester (Shimadzu Corporation, product name: Autograph (registered trademark) AG-X20kN) at a speed of 300 mm / min, a width of 15 mm, and a measurement temperature of 110 ° C, using a 180° peel method.

[0061] (Method for measuring linear expansion coefficient) An adhesive film with a heat-resistant layer thickness of 20 μm, an adhesive layer thickness of 80 μm, and a total thickness of 100 μm was used as the sample. The sample was cut to a size of 4 mm x 50 mm, and both ends in the longitudinal direction were fixed to chucks with a distance of 20 mm between the chucks. After heating from 23°C to 110°C at a tension of 0.01 N / mm and a heating rate of 5°C / min, the sample was held at 110°C for 5 minutes, and the linear expansion coefficient of the sample was measured. In Table 1, the coefficient of linear expansion of 200×10 -6 If the temperature exceeded 200°C, it was written as ">200".

[0062] (result) The above results are summarized in Table 1.

[0063] [Table 1]

[0064] The adhesive films of Examples 1 to 9 had high adhesive strength and low thermal expansion coefficients even at high temperatures, and it was therefore possible to achieve both good adhesion to the adherend and dimensional retention of the adhesive film.

[0065] In the adhesive film of Comparative Example 1, the adhesive layer had sufficient adhesion to the adherend, but the adhesion between the heat-resistant layer and the adhesive layer was insufficient, resulting in weak adhesive strength at high temperatures. The adhesive film of Comparative Example 2 had a low heat resistance layer and poor dimensional retention at high temperatures. [Explanation of symbols]

[0066] 10, 20, 30...adhesive film, 11...heat-resistant layer, 12...adhesive layer, 13...second adhesive layer.

Claims

1. A cyclic olefin resin layer is provided as a heat-resistant layer, an adhesive layer on at least one surface of the heat-resistant layer; The adhesive layer an acid-modified polyolefin resin; At least one selected from a styrene-based elastomer, a C5 to C9 petroleum resin, and a C9 petroleum resin is present in a total amount of 3 to 50 parts by weight per 100 parts by weight of the adhesive layer; Including, the glass transition temperature of the cyclic olefin resin contained in the cyclic olefin resin layer is 130°C or higher; An adhesive film used for bonding to metal, glass, or ceramics.

2. The adhesive film according to claim 1, wherein the acid-modified polyolefin resin of the adhesive layer is modified with an unsaturated carboxylic acid component, and the acid-modified polyolefin resin contains 0.01 to 2 parts by weight of the unsaturated carboxylic acid component per 100 parts by weight of the acid-modified polyolefin resin.

3. The adhesive film according to claim 1 or 2, wherein the acid-modified polyolefin resin is an acid-modified polypropylene resin.

4. A method for producing the adhesive film according to any one of claims 1 to 3, a step of melt-kneading the material of the heat-resistant layer in a melt extruder and extruding the heat-resistant layer into a film; a step of melt-kneading a material for the adhesive layer in a melt extruder and laminating the adhesive layer on at least one surface of the heat-resistant layer by extrusion lamination; A method for producing an adhesive film comprising the steps of:

5. A method for producing the adhesive film according to any one of claims 1 to 3, A method for manufacturing an adhesive film, comprising the steps of melt-kneading the materials of the heat-resistant layer and the adhesive layer in an extruder, respectively, and extruding and molding them simultaneously to form the heat-resistant layer and the adhesive layer into a film with the adhesive layer laminated on at least one side of the heat-resistant layer.

6. A method for producing the adhesive film according to any one of claims 1 to 3, a step of melt-kneading the material of the heat-resistant layer in a melt extruder and extruding the heat-resistant layer into a film; a step of melt-kneading the material of the adhesive layer in a melt extruder and extruding the adhesive layer into a film; a step of laminating the adhesive layer on at least one surface of the heat-resistant layer by pressing with a hot roll; A method for producing an adhesive film comprising the steps of:

7. A method for producing an adhesive structure, comprising a step of adhering the adhesive film according to any one of claims 1 to 3 to the surface of an adherend made of metal, glass, or ceramic.

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