Anticorrosive laminate film and anticorrosive tape

Abstract

To provide an anti-corrosion laminate film and anti-corrosion tape, which have an excellent workability, excellent waterproof and anti-corrosion properties, and long-term durability, and which hardly cause a pinhole and crack due to an external physical stress.SOLUTION: There are provided an anti-corrosion laminate film that comprises a metal foil and an adhesive layer laminated on one or both sides of the metal foil, in which the adhesive layer is composed of a thermoplastic thermal-adhesive resin; and an anti-corrosion tape in which a double-sided tape obtained by impregnating an acrylic foam with an acrylic-based pressure-sensitive adhesive is laminated onto the anti-corrosion laminate film.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a material for waterproofing or corrosion prevention of steel materials used in civil engineering and construction, and more particularly to an anticorrosive laminate film and anticorrosive tape that can maintain waterproofing and corrosion prevention for a long period of time for buildings and is suitable as a waterproofing and corrosion prevention laminate film and tape to be attached to the surface of steel materials used as components of structures, etc. More specifically, the present invention relates to an anticorrosive laminate film and anticorrosion tape that are suitable for preventing corrosion of steel materials used in various structures such as buildings, marine structures, steel towers, elevated water tanks, tanks, water gates, bridges, plants, etc. [Background technology]

[0002] There are many different types of steel used as components for buildings, marine structures, steel towers, elevated water tanks, tanks, water gates, bridges, plants, etc., with strength, corrosion resistance, heat resistance, magnetic properties, thermal expansion coefficient, etc. adjusted by the carbon content and heat treatment method depending on the application and purpose.

[0003] If such steel materials are left as they are indoors or outdoors, they will corrode and develop red rust or yellowish-brown floating rust, which not only mars the scenery but also reduces the strength of the structure due to a decrease in thickness caused by corrosion, and in severe cases may even cause damage.

[0004] Conventionally, as a countermeasure against corrosion of such steel materials over time, it has been common to apply a coating having anticorrosive or antirust properties, as disclosed in Patent Document 1.

[0005] On the other hand, Patent Documents 2 and 3 propose imparting corrosion resistance to the surface of a steel material by attaching a waterproof film made of a resin layer or a metal layer to the surface of the steel material via an adhesive.

[0006] For example, Patent Document 2 describes a waterproof adhesive tape in which a substrate made of a material with low water permeability, for example a rubber material such as butyl rubber, or a resin material such as acrylic, silicone, polyethylene, epoxy, or urethane, is coated with an adhesive whose main components are natural rubber, styrene-butadiene rubber, butyl rubber, or acrylic rubber; it is preferable for this waterproof adhesive tape to have a film thickness of 0.1 to 2.0 mm, an adhesive strength of 1 kg·cm or more, and a water absorption rate of 1.0% or less.

[0007] Patent Document 3 describes a method for protecting steel material from corrosion by applying an adhesive to the surface of the steel material and attaching a resin sheet having a fiber layer or metal layer that imparts elasticity to the inside or surface of a resin layer made of polyvinyl chloride.

[0008] Patent Document 4 describes a heavy-duty corrosion-resistant coated steel material having a vapor-deposited base film layer on which an inorganic substance is vapor-deposited.

[0009] Patent Document 5 describes a steel material repair method that includes a step of attaching metal foil to the surface of the steel material so as to cover the corroded portion. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] JP 2004-97945 A [Patent Document 2] JP 2001-81800 A [Patent Document 3] JP 2013-71267 A [Patent Document 4] JP 2005-262787 A [Patent Document 5] JP 2020-33730 A Summary of the Invention [Problem to be solved by the invention]

[0011] The corrosion prevention method using paint as in Patent Document 1 does not provide sufficient corrosion prevention effect, and there are problems in that corrosion easily progresses in places where moisture is likely to accumulate, where salt is likely to adhere, and in corners where the paint film is likely to thin. There are also problems in that the painting cost is high, the service life is limited, and regular repainting is required, resulting in high maintenance costs.

[0012] In the method of attaching a waterproof film consisting of a resin layer or a metal layer to the surface of a steel material via an adhesive as described in Patent Documents 2 and 3, the anticorrosive effect can be enhanced by selecting the resin layer or the metal layer, but when used outdoors, there is a problem that pinholes and cracks are likely to occur when sand, pebbles, etc. collide with the film surface due to wind and rain, and the anticorrosive properties cannot be maintained for a long period of time. If the metal layer is made thicker to prevent pinholes and cracks, the sheet becomes harder, causing problems with application to steel materials. Furthermore, the waterproof resin sheet used as the film substrate has poor adhesion to paints and adhesives, and there is also the problem of peeling.

[0013] The heavy-duty corrosion-resistant coated steel material having an inorganic vapor-deposited base film layer described in Patent Document 4 has improved moisture barrier properties and increased durability compared to resin films, but is prone to pinholes and cracks and is insufficient for maintaining corrosion resistance for a long period of time. In addition, the film strength is insufficient and there is a possibility of damage due to external forces.

[0014] In the method of applying a metal foil to cover a corroded part on a steel surface as described in Patent Document 5, a thin metal foil has insufficient strength and is susceptible to breakage due to external force. A thick metal foil increases the strength, but is too hard, which causes problems in handling and application, and limits the scope of application.

[0015] As described above, various corrosion prevention methods and various corrosion prevention films have been proposed in the past to impart corrosion resistance to steel materials. However, there is a problem that the corrosion resistance of steel materials cannot be maintained for long periods of time, and maintenance is required every time the steel material corrodes. Furthermore, when pebbles or other debris collide with the steel due to wind and rain, pinholes and cracks can form, compromising the barrier properties and making the steel more susceptible to corrosion.

[0016] The present invention has been made in consideration of the above-mentioned circumstances, and an object of the present invention is to provide an anticorrosive laminate film and an anticorrosive tape which have excellent workability, excellent waterproofing, anticorrosion properties, and long-term durability, and which are also resistant to the occurrence of pinholes and cracks even when subjected to physical external stress. [Means for solving the problem]

[0017] As a result of extensive investigation into the above problems, the present inventors have found that the above problems can be easily solved by employing a specific configuration, and have thus completed the present invention.

[0018] That is, the gist of the present invention is A corrosion-preventive laminate film comprising a metal foil and an adhesive layer laminated on one or both sides of the metal foil, the adhesive layer being made of a thermoplastic heat-adhesive resin. a corrosion-preventive tape comprising the corrosion-preventive laminate film and a moisture-curable pressure-sensitive adhesive layer; and a corrosion-prevention tape comprising a double-sided tape made of an acrylic foam impregnated with an acrylic adhesive and laminated to the corrosion-prevention laminate film; It resides in. Effect of the Invention

[0019] The present invention provides an anticorrosive laminate film and an anticorrosive tape which are excellent in workability, waterproofness, anticorrosion properties and their long-term durability, and pinhole resistance, and which can be produced inexpensively by a method that places little strain on the environment. By using the anticorrosive laminate film and anticorrosive tape of the present invention, rusting and deterioration of steel materials can be prevented effectively and at low cost, thereby improving the long-term durability and reliability of steel materials used in various structures. [Brief description of the drawings]

[0020] [Figure 1] 1 is a schematic cross-sectional view showing an example of an embodiment of the anticorrosive laminate film and anticorrosive tape of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing another example of an embodiment of the anticorrosive laminate film and anticorrosive tape of the present invention. [Diagram 3] FIG. 2 is a schematic cross-sectional view showing another example of an embodiment of the anticorrosive laminate film and anticorrosive tape of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 3 showing an example of an embodiment of the anticorrosive laminate film and anticorrosion tape of the present invention, but the present invention is not limited to the following embodiment.

[0022] [Anti-corrosion laminate film] The anticorrosive laminate film of the present invention is characterized in that it comprises a metal foil and an adhesive layer laminated on one or both sides of the metal foil, the adhesive layer being made of a thermoplastic heat-adhesive resin.

[0023] [Adhesive layer] In the present invention, an adhesive layer made of a thermoplastic heat-adhesive resin is provided on at least one surface of the metal foil.

[0024] In the present invention, the adhesive layer made of a thermoplastic heat-bonding resin also functions as a protective layer for protecting the metal foil for a long period of time. Therefore, by providing an adhesive layer made of a thermoplastic heat-bonding resin on the metal foil, the waterproof and corrosion-resistant properties and strength of the metal foil can be improved, and as a result, by attaching it to a material to be protected such as steel, the waterproof and corrosion-resistant properties of the material to be protected such as steel can be significantly improved. Here, the term "thermal adhesive resin" refers to a resin that exhibits adhesive properties when heated and melted. In addition, "adhesiveness" refers to a strength of 3N / 15mm or more when measured using a T-peel test method under normal temperature and humidity conditions of 23°C and 50% after the thermal adhesive resin is heated to above its melting point and adhered to a metal foil.

[0025] Examples of the thermoplastic heat-adhesive resin constituting the adhesive layer include thermoplastic resins containing the following resins as main components. Metal-modified polyolefin resin Acid-modified resins in which a portion of a thermoplastic resin is modified with acid, such as polyolefin resins modified with maleic anhydride, Polyvinyl acetate resin Epoxy-modified resin, mixed resin containing at least one of glycidyl methacrylate, vinyl acetate, methyl acrylate, etc. Resin made by copolymerizing ethylene with acrylic acid, etc., and adding polar groups such as carboxyl groups Ionomer resins, for example, resins with ionic bonds between polymer structures, in which alkali metals or alkaline earth metals are bonded to copolymers of ethylene and acrylic acid or methacrylic acid to form cross-linked structures.

[0026] In the present invention, the term "main component" refers to the component that is contained in the largest amount by weight in a material that is a blend of multiple components. Preferably, the main component of a thermoplastic thermal adhesive resin is a component that occupies 50% or more by weight of 100% by weight of the thermoplastic thermal adhesive resin, more preferably 70% or more by weight, and even more preferably 80% or more by weight and 100% or less by weight.

[0027] These thermoplastic thermal adhesive resins differ from dry lamination adhesives used in laminate films for general packaging materials; they are heated and melted, then heated and pressed against metal foil, and then cooled and solidified, causing crystalline lamellae to grow toward the metal foil, not only helping to protect the metal foil from water and UV rays, but also reacting strongly with the polar groups on the surface of the metal foil, which has barrier properties, and the flexibility unique to thermoplastic resins helps to mitigate external physical stress, protecting the metal foil and allowing it to maintain its adhesive strength and waterproof and corrosion-resistant properties for a long period of time.

[0028] Of the above-listed resins, the thermoplastic thermal adhesive resin is preferably an acid-modified polyolefin resin or an acid-modified fluororesin, from the viewpoint of excellent protective effect.

[0029] Examples of the acid-modified polyolefin resin include acid-modified polyethylene resins mainly composed of high-, medium-, low-, or linear low-density polyethylene, and acid-modified polypropylene resins mainly composed of random or block polypropylene. As the acid-modified fluororesin, an acid-modified fluororesin copolymerized with an ethylene component is easy to use because of its low melting point. Particularly preferred are flexible low-density polyethylene, acid-modified polyethylene resins mainly composed of linear low-density polyethylene (LLPE), acid-modified polypropylene resins mainly composed of random or block polypropylene, acid-modified ETFE obtained by acid-modifying ethylene tetrafluoroethylene (ETFE), and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), and acid-modified PFA.

[0030] The melting point of these thermoplastic thermal adhesive resins is preferably 60° C. or more and 250° C. or less in terms of lamination processability and adhesion to metal foil. Also, the thermoplastic thermal adhesive resin preferably has a resin fluidity, indicated by a melt flow rate (MFR), of 0.1 g / 10 min to 20 g / 10 min in terms of lamination processability and adhesion, as well as the melting point. The melting point and MFR herein are values ​​measured by the method described in the Examples section below.

[0031] Linear low density polyethylene (LLPE) refers to a copolymer of ethylene and an α-olefin having about 4 to 20 carbon atoms. Specific examples of the branched side chain composed of α-olefin include one or more of various comonomers such as butene-1, hexene-1, 4-methylpentene-1, octene-1, decene-1, tetracene-1, and octadecene-1.

[0032] The reason why the acid-modified polyethylene resin is preferable as the acid-modified polyolefin resin serving as the thermoplastic thermal adhesive resin is as follows. Polyethylene resin has a lower melting point than polypropylene resin, but it is a polymer whose molecules cross-link when exposed to repeated heat. It is less susceptible to molecular scission when exposed to harsh high-temperature environments of 80 to 90°C for long periods of time, and has better long-term heat resistance than polypropylene resin. Furthermore, polyethylene resin has high melt tension, is flexible, and is resistant to deformation when laminated to steel materials of any shape, does not easily turn white when deformed, and has excellent cold resistance. Polyethylene resin also has a higher density than polypropylene resin, and is highly resistant to moisture and ultraviolet rays from the outside. Such acid-modified polyethylene resins have excellent adhesion to metal foils, such as aluminum foils, and can obtain strong adhesion without the need for chromium-based or phosphorus-based chemical conversion treatments, which cause environmental pollution, on the aluminum foil.

[0033] The acid-modified polyolefin resin and the acid-modified fluororesin used in the present invention may be at least partially acid-modified. The acid-modified polyolefin resin and the acid-modified fluororesin can be produced, for example, by modifying a polyolefin resin or a fluororesin with an unsaturated carboxylic acid and / or a derivative thereof through graft polymerization.

[0034] The unsaturated carboxylic acid and derivatives of unsaturated carboxylic acid used for modification are not particularly limited, and examples thereof include dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid, and mesaconic acid; unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid; and anhydrides, amides, imides, esters, and other derivatives of dicarboxylic acids such as maleic anhydride, fumaric anhydride, itaconic anhydride, and mesaconic anhydride. Among these, it is preferable to use maleic acid, maleic anhydride, acrylic acid, and methacrylic acid, and maleic anhydride is particularly suitable.

[0035] Methods for modifying polyolefin resins are not particularly limited, but examples include a solution method in which a polyolefin resin such as a polyethylene resin or a polypropylene resin is dissolved in an organic solvent and reacted with an acid (such as maleic anhydride) in the presence of a radical generator, and a melt method in which such a resin is heated and melted and reacted with an acid (such as maleic anhydride) in the presence of a radical generator.

[0036] The polyolefin resin to be subjected to acid modification may be linear low-density polyethylene (LLPE), which is suitable as a main component, or other polyethylene resins that can be used in combination therewith, such as high-density polyethylene (HDPE), medium-density polyethylene (MDPE), low-density polyethylene (LDPE), or polypropylene resins, such as random polypropylene (RPP). Low-density polyethylene (LDPE) does not include the linear low-density polyethylene (LLPE), and generally includes what is called high-pressure low-density polyethylene.

[0037] In addition, an acid-modified polyolefin resin and a non-acid-modified polyolefin resin can be appropriately mixed and used. When an acid-modified polyolefin is used in combination with another polyolefin resin, these polyolefin resins may be mixed or coexisted and acid-modified, or at least one of the polyolefin resins may be acid-modified in advance and then mixed with the other non-acid-modified polyolefin resin.

[0038] If the modification rate of the acid-modified polyolefin resin (the content of acid groups in the acid-modified polyolefin resin) is too low, the effect of improving adhesiveness due to the acid modification may not be fully obtained, and if it is too high, the heat resistance of the acid-modified polyolefin resin tends to decrease, so it is preferable that the modification rate is 0.05% by weight or more and 10% by weight or less, and particularly 0.2% by weight or more and 5% by weight or less. The modification rate of the acid-modified polyolefin resin can be confirmed by, for example, infrared absorption spectroscopy (IR) or titration. In addition, in the case where an acid-modified polyolefin resin and a non-acid-modified polyolefin resin are blended and used, the modification rate means the modification rate in the entire polyolefin resin including the non-acid-modified polyolefin resin.

[0039] As the acid-modified polyolefin resin, a commercially available product can be used. For example, a product corresponding to the above can be appropriately selected from the Modic (product name) series manufactured by Mitsubishi Chemical Corporation and Admer (product name) manufactured by Mitsui Chemicals, Inc.

[0040] The adhesive layer may contain a resin other than the acid-modified polyolefin resin as long as it does not impair the effects of the present invention. The resin other than the acid-modified polyolefin resin is not limited, but examples thereof include ethylene-based resins obtained by copolymerizing ethylene with a comonomer other than α-olefin, such as glycidyl methacrylate resin, vinyl acetate resin, methyl acrylate resin, ethylene-vinyl acetate copolymer, and ethylene-vinyl alcohol copolymer; propylene-based resin, vinyl chloride resin, polyamide resin, polyester resin, polycarbonate resin, etc. In addition, when the adhesive layer contains a large amount of resin other than the acid-modified polyolefin resin, the effect of using the acid-modified polyolefin resin may be impaired, so it is preferable to use these resins in the adhesive layer in a range of 20% by weight or less, preferably 15% by weight or less. Furthermore, the adhesive layer may be a layer in which one or more olefin-based elastomers selected from the group consisting of ethylene-propylene copolymers, ethylene-butene copolymers, propylene-butene copolymers, ethylene-propylene-butene copolymers, and ethylene-propylene-diene copolymers are blended with the acid-modified polyolefin resin as described above, in a total amount of 5% by weight or more and 30% by weight or less, particularly 7% by weight or more and 25% by weight or less in the adhesive layer, when two or more types are used. When the adhesive layer contains these olefin-based elastomers, these elastomer components are oriented in the thickness direction when the films are bonded by thermal lamination, which has the effect of driving a wedge of the acid-modified polyolefin resin into the metal foil and the effect of promoting crystallization of the acid-modified polyolefin resin in the adhesive layer, resulting in a corrosion-resistant laminate film with excellent long-term water resistance and weather resistance.

[0041] On the other hand, examples of acid-modified fluororesins include those obtained by modifying ETFE with an acid, those obtained by modifying PFA with an acid, and the like. There are no particular limitations on the acid-modified fluororesins, and commercially available thermoplastic fluororesins may also be used.

[0042] In particular, fluororesin is preferred because it inherently has excellent weather resistance, produces very little plasticizer bleeding, has high density and excellent water resistance, and is therefore less restricted by the grade characteristics of the resin. If it can be directly bonded to metal foil, it is preferred because it can dramatically improve the long-term corrosion resistance of the metal foil. From the viewpoints of processability, ease of handling, and adhesiveness, it is preferable to use an acid-modified fluororesin having a melting point of 230° C. or less.

[0043] If the modification rate of the acid-modified fluororesin (the content of acid groups in the acid-modified fluororesin) is too low, the effect of improving adhesion due to the acid modification may not be fully obtained, and if it is too high, the heat resistance of the acid-modified fluororesin tends to decrease, so it is preferably 0.05% by weight or more and 10% by weight or less, particularly 0.2% by weight or more and 5% by weight or less. The modification rate of the acid-modified fluororesin can be confirmed by, for example, infrared absorption spectroscopy (IR) or titration. In addition, when an acid-modified fluororesin and a non-acid-modified fluororesin are blended and used, the modification rate means the modification rate in the entire fluororesin including the non-acid-modified fluororesin.

[0044] As the acid-modified fluororesin, commercially available products can be used, and for example, those corresponding to the above can be appropriately selected and used from among Neoflon (product name) manufactured by Daikin Corporation, Fluon (product name) manufactured by AGC Corporation, etc.

[0045] The adhesive layer may contain only one type of such acid-modified resin, or may contain two or more types.

[0046] The adhesive layer may also contain various additives such as antioxidants, heat stabilizers, various plasticizers, light stabilizers, ultraviolet absorbers, ultraviolet reflectors, radical trapping materials, neutralizing agents, lubricants, anti-fogging agents, anti-blocking agents, crosslinking agents, crosslinking assistants, colorants, flame retardants, and dispersing agents. For example, the adhesive layer may contain a polymeric hindered amine light stabilizer, which is preferably used as a light stabilizer as described below, in a suitable content as described below.

[0047] The adhesive layer preferably has an MFR of 0.1 g / 10 min or more and 25 g / 10 min or less. If the MFR of the adhesive layer is more than 25 g / 10 min, the molecular weight becomes small, and the long-term water resistance and weather resistance tend to be poor. The MFR of the adhesive layer is more preferably 20 g / 10 min or less, and even more preferably 10 g / 10 min or less. The lower limit of the MFR of the adhesive layer is preferably 0.1 g / 10 min or more because it is preferable that the level is not problematic in film formation when film formation is performed by inflation molding, and is particularly preferably 0.3 g / 10 min or more because it is possible to maintain high-speed formability and high seal strength in inflation molding.

[0048] The density of the adhesive layer is 0.88 g / cm for polyolefin-based adhesives. 3 If the density is lower than this, the density of the adhesive layer should be higher in order to improve the water resistance to block moisture from the outside, and the lower limit of the preferred density is 0.91 g / cm. 3 More preferably, it is 0.92 g / cm 3 The upper limit of the density of the adhesive layer is not particularly limited as long as it does not impair the flexibility of the polyolefin resin, but the upper limit of the density is usually 0.96 g / cm 3 Taking into consideration the adhesiveness to the metal foil and the resistance to whitening due to deformation during construction, the preferred thickness is 0.95 g / cm 3 The following is the result. The means for setting the density of the adhesive layer within the above range are not limited, but include optimizing the polyolefin resin such as polyethylene resin used for acid modification, optimizing the modification rate, and, as described above, using a polyolefin resin that is not acid-modified or a resin other than polyolefin resin in combination and optimizing the blending ratio thereof. Also, for fluorine-based materials, the normal density is 1g / cm 3 In addition, fluororesin itself has excellent weather resistance and water resistance, so this is not a problem. Taking into account copolymerization with other components and alloys with other materials, the density of fluororesin is 1.5 g / cm 3 It is preferable that the concentration is 1.7 g / cm or more. 3 More than 2.2g / cm 3 It is particularly preferable that the thickness is below this range, since the effects of the fluororesin are exhibited in terms of adhesion to the metal foil and water resistance.

[0049] The tensile modulus of the adhesive layer is preferably 100 MPa or more because too much flexibility can easily cause material destruction when an external force such as deformation is applied, and conversely, if it is too hard, it can easily become brittle and peel off at the interface with the metal foil, so it is preferably 2000 MPa or less. The tensile modulus of the adhesive layer is more preferably 130 MPa or more and 800 MPa or less, and particularly preferably 180 MPa or more and 600 MPa or less.

[0050] The melting point of the adhesive layer is preferably 70° C. or higher and 230° C. or lower, particularly preferably 90° C. or higher and 200° C. or lower. If a thermoplastic heat-adhesive resin having a melting point higher than the above temperature is used, it is preferable because the light stabilizer and antioxidant contained therein are decomposed by the heating temperature during extrusion processing, causing problems such as a decrease in molecular weight, resulting in bleeding out and disappearance, and causing thermal degradation of the acid-modified resin.

[0051] The above-mentioned values ​​of MFR, density, tensile modulus, and melting point refer to the properties of the thermoplastic thermal adhesive resin constituting the adhesive layer, and in the case where multiple resins are used in combination or where a material other than resin is contained, they refer to the values ​​as a resin composition. The methods for measuring these physical properties are as shown in the Examples section below.

[0052] In the present invention, when a film made by an inflation molding method in which a thermoplastic thermal adhesive resin is extruded from a circular die is used as the adhesive layer, a homogeneous adhesive film without differences in physical properties such as tensile strength and elongation in the vertical and horizontal directions can be obtained. Furthermore, when a high elasticity resin layer or a low elasticity resin layer described later is laminated as a protective layer, even if a uniaxially or biaxially stretched film or a non-stretched film having a difference in mechanical strength in the vertical and horizontal directions such as a T-die molding method is used as the protective layer, defects due to the vertical and horizontal directions are unlikely to occur when the protective layer is processed into a case shape, which is preferable because it increases the options for films that can be used as the protective layer.

[0053] In the anticorrosive laminate film of the present invention, the adhesive layer is provided on at least one side of the metal foil, and may be provided on both sides of the metal foil. Furthermore, when a high elasticity resin layer or a low elasticity resin layer is provided as a protective layer described below, it may be provided so as to be interposed between the protective layer and the metal foil, or between two protective layers. The adhesive layer may form the outermost layer of the anticorrosive laminate film of the present invention. In either case, when the corrosion-resistant laminate film of the present invention is applied to the outer surface side of a metal foil, i.e., to the material to be protected from corrosion, such as steel, it is preferable to have at least an adhesive layer on the side opposite the material to be protected, as this also has the effect of a protective layer.

[0054] The adhesive layer provided on the outer surface side of the metal foil preferably contains a light stabilizer from the viewpoint of improving light resistance and weather resistance.

[0055] The thickness of the adhesive layer is preferably 2 μm to 100 μm, more preferably 5 μm to 50 μm, and particularly preferably 8 μm to 40 μm. If the thickness of the adhesive layer is thinner than the above range, sufficient adhesive strength for adhesion to the metal foil may not be obtained, and if the thickness is thicker than the above range, flexibility may be lost and problems may occur in workability. Here, the thickness of the adhesive layer refers to the thickness per adhesive layer (per location). Here, one adhesive layer refers to a layer that does not include a protective layer or the like described below, such as a metal foil or a layer adjacent to a protective layer described below, and if one adhesive layer has a laminated structure of multiple layers, it corresponds to the total thickness of the layers.

[0056] [Metal foil] The metal foil is a layer that acts as a barrier to prevent moisture from penetrating into the interior from the outside, and is required to be free of pinholes, have high tensile strength as an anticorrosive laminate film, and be resistant to cracking against deformation and stretching due to external forces.

[0057] As the metal foil, aluminum or its alloy, SUS stainless steel, etc., which is corrosion-resistant and inexpensive, can be used. In terms of crack resistance, pure Al (aluminum) with a purity of 99% or more, Al-Cu-Mg alloys, Al-Mn alloys, Al-Si alloys, Al-Mg alloys, Al-Mg-Si alloys, Al-Zn-Mg alloys, Al-Fe alloys, etc. can be used. The aluminum content in the Al alloy is preferably 95% by weight or more.

[0058] Among these, the metal foil is preferably an aluminum foil with excellent elongation, and aluminum foil containing 0.1% to 3.0% by weight of iron (alloy number 8000 series) or pure aluminum with a purity of 99% or more (alloy number 1000 series) is preferable. In the above-mentioned aluminum foil containing 0.1% to 3.0% by weight of iron, if the iron content is less than this range, the elongation tends to be insufficient, and if it is more than this range, the metal foil tends to be easily corroded. The preferable iron content of the iron-containing aluminum foil is 0.2% to 1.7% by weight, particularly preferably 0.3% to 1.7% by weight. Furthermore, there are hard aluminum foils and soft aluminum foils as aluminum foils, and soft aluminum foils that have been annealed are preferred because they have flexibility.

[0059] The thickness of the metal foil such as an aluminum foil is preferably from 6 μm to 100 μm, particularly from 9 μm to 25 μm, in order to achieve both a thin film and good barrier properties.

[0060] <Surface treatment of aluminum foil> The surface of the aluminum foil suitable as the metal foil in the present invention may be subjected to a surface treatment to impart corrosion resistance. However, in the present invention, the surface treatment of the aluminum foil is not necessarily required.

[0061] When performing surface treatment on aluminum foil, known treatments are used as the surface treatment. For example, chromium-based chemical conversion treatments such as chromate chromate treatment, phosphate chromate treatment, phosphate-chromate treatment, chromate treatment, alkali chromate treatment, coating type chromate treatment, or coating type non-chromium-based treatments such as zirconium, titanium, zinc phosphate, boehmite treatment, anodization treatment, etc. may be mentioned. In addition to these treatments, a treatment to impart polar groups to the aluminum foil surface such as corona treatment, plasma treatment, flame treatment, or primer treatment may be performed to increase adhesion with the adhesive layer made of a thermoplastic thermal adhesive resin, thereby imparting corrosion resistance. In addition, two or more of these treatments may be combined. However, it is preferable not to perform chromium-based chemical conversion treatments from the viewpoint of environmental protection.

[0062] [Protective layer] The anticorrosive laminate film of the present invention may further have a high elasticity resin layer or a low elasticity resin layer as a protective layer in order to improve weather resistance, etc. The protective layer is usually provided by laminating it on the metal foil via an adhesive layer. Alternatively, the protective layers are provided by laminating each other via an adhesive layer.

[0063] <High elasticity resin layer> The highly elastic resin layer in the present invention is a layer for preventing damage to the metal foil due to external forces such as piercing, reinforcing the metal foil, and preventing damage to the film itself due to external physical stress, and may be a single-layer film or a laminated film of two or more layers.

[0064] The highly elastic resin layer is required to have excellent mechanical strength, excellent protection for the metal foil, and barrier properties, and is preferably made of a resin film having a relatively high tensile modulus of elasticity, since this allows the film thickness to be reduced.

[0065] Examples of resins constituting the highly elastic resin layer include polyamide (PA or Ny), polyamideimide (PAI), polyacetal (POM), polyarylate (Par), polycarbonate (PC), polyalkylene terephthalates (PAT) such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polytrimethylene terephthalate (PTT), polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), polymethyl methacrylate (PMMA), polyphenylene oxide (PPE), polyethersulfone (PES), polymethylpentene (TPX), polyoxybenzylene (POB), polyimide (PI), liquid crystalline polyester, polysulfone (PSF), polyphenylene sulfide (PPS), polybisamidotriazole, polyaminobismaleimide, polyetherimide (PEI), polyetheretherketone (PEEK), and the like, or a mixture of two or more of these. Among these, those made of polycarbonate (PC), polybutylene terephthalate (PBT), polyalkylene terephthalate (PAT) such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), polyamide (PA or Ny), polyphenylene sulfide (PPS), polyamideimide (PAI), and polyimide (PI) are preferable.

[0066] The high elasticity resin layer may be a non-stretched film or a stretched film, but from the viewpoint of mechanical strength and heat resistance, the high elasticity resin layer is preferably made of a stretched film, and more preferably a biaxially stretched film. In particular, those made of a biaxially stretched polyethylene terephthalate film, a biaxially stretched polyethylene naphthalate film, a biaxially stretched polyamide film, or a biaxially stretched polybutylene terephthalate film are preferable because they have a moderately high tensile modulus and are inexpensive.

[0067] Among these, biaxially oriented polyamide films and biaxially oriented polybutylene terephthalate films are more preferable because they also have appropriate flexibility. Furthermore, biaxially oriented polyamide films and biaxially oriented polybutene terephthalate films produced by the tubular method are particularly preferred, with biaxially oriented polyamide films being particularly preferred, in that they have little anisotropy in the film directions (longitudinal and transverse directions).

[0068] The highly elastic resin layer must also play a role in preventing the formation of pinholes and cracks in the metal foil due to deformation caused by external punctures, etc., and must have a certain degree of elasticity and thickness in order to prevent damage to the corrosion-resistant laminate film during installation. From this viewpoint, it is preferable that the tensile modulus of the high-elasticity resin layer is, as a maximum value in the plane of the film (usually either the extrusion direction (longitudinal direction) or the width direction of the film), 1500 MPa or more, particularly 1700 MPa or more, and especially 2000 MPa or more. If the tensile modulus of elasticity of the highly elastic resin layer is less than 1500 MPa, the effect of reinforcing the metal foil tends to be reduced, and pinholes and cracks tend to occur more easily due to external stress.

[0069] There is no particular upper limit to the tensile modulus of the high-elasticity resin layer, but the maximum value in the film plane is preferably 6500 MPa or less. If the tensile modulus is greater than this, the anticorrosive laminate film of the present invention becomes too hard and loses flexibility, so the thickness must be reduced, and pinhole resistance and puncture resistance may deteriorate. In addition, when the anticorrosive laminate film is attached to a corner while being bent, the return force becomes stronger over time, and peeling may occur. The upper limit of the tensile elastic modulus of the highly elastic resin layer is more preferably 5000 MPa or less, and particularly preferably 4500 MPa or less.

[0070] In addition, the thickness of the high elasticity resin layer is preferably 5 μm or more and 50 μm or less. If the thickness of the high elasticity resin layer is thicker than 50 μm, the rigidity of the anticorrosive laminate film of the present invention becomes too high, making it difficult to bend and difficult to attach to the corners of steel materials, making it difficult to install, and the surface density tends to increase and it becomes difficult to reduce the weight. On the other hand, if the thickness of the high elasticity resin layer is thinner than 5 μm, it may affect the puncture resistance. The thickness of the high elasticity resin layer is particularly preferably 8 μm or more and 30 μm or less. Here, the thickness of the high-elasticity resin layer refers to the thickness of each high-elasticity resin layer (per location). Here, one high-elasticity resin layer is a layer that does not include an adhesive layer, for example, a layer between adhesive layers, and if one high-elasticity resin layer has a laminated structure of multiple layers, it corresponds to the total thickness of the layers.

[0071] In particular, when the pierceability of the anticorrosive laminate film is to be improved, the highly elastic resin layer is preferably provided on the front side of the metal foil, that is, on the side opposite to the material to be protected via the metal foil.

[0072] <Low elasticity resin layer> When flexibility and solvent resistance are important in anticorrosive laminate film of the present invention in anticipation of the application of paint or adhesive, a flexible, low-elasticity resin layer having a low tensile modulus of elasticity, such as polyolefin, may be further laminated thereon.

[0073] For example, as shown in Fig. 1, low-elasticity resin layers 1a and 1b having solvent resistance are laminated on both sides of the metal foil, or as shown in Fig. 2, multiple low-elasticity resin layers 1a, 1b, and 1c are laminated on the surface side of a high-elasticity resin layer 4 having a high tensile modulus of elasticity, thereby imparting flexibility, improving workability such as handling, and improving resistance to paints and adhesives containing solvents, which is preferable. In addition, although not shown, when a low-elasticity resin layer is provided only on the side of the metal foil to be protected, workability can be improved by imparting flexibility.

[0074] Examples of resins constituting the low elasticity resin layer include polyolefins such as polypropylene, polyethylene (high density, medium density, low density, linear low density), propylene-ethylene block or random copolymers, and acid-modified products thereof, rubber or latex components such as ethylene-propylene copolymer rubber, styrene-butadiene rubber, styrene-butadiene-styrene block copolymers or hydrogenated derivatives thereof, polybutadiene, polyisobutylene, polyvinylidene fluoride (PVDF), polyvinyl fluoride, chlorotrifluoroethylene, ethylene-tetrafluoroethylene copolymer (ETFE), polytetrafluoroethylene (PTFE), hexafluoropropylene, perfluoroalkyl vinyl ether copolymers, acrylic acid alkyl ester copolymers, polyester ester copolymers, polyether ester copolymers, polyether amide copolymers, polyurethane copolymers, vinyl chloride resins, and the like, or mixtures of two or more of these.

[0075] In particular, the low-elasticity resin layer is preferably made of polypropylene, polyethylene (high density, medium density, low density, linear low density), polyolefins such as propylene-ethylene block or random copolymers and acid-modified products thereof, rubber or latex components such as ethylene-propylene copolymer rubber, styrene-butadiene rubber, styrene-butadiene-styrene block copolymers or hydrogenated derivatives thereof, polybutadiene, or polyisobutylene, for example, in order to impart impact resistance and weather resistance to protect the high-elasticity resin layer from impact and the external environment, and to prevent deterioration due to solvents contained in the adhesive when the layer is attached to a material to be protected such as steel.

[0076] In the present invention, the low elasticity resin layer can be appropriately selected from polyethylene resins, i.e., those mainly composed of high-density, medium-density, low-density, or linear low-density polyethylene, polyolefin resins mainly composed of random or block polypropylene, and polyolefin resins modified with acid or silane. Among these, preferred are single-layer or laminated structures containing a polyethylene resin layer mainly composed of linear low-density polyethylene (LLPE), high-density polyethylene, or medium-density polyethylene, and also preferred are single-layer or laminated structures containing a resin layer mainly composed of block polypropylene (BPP) or random polypropylene (RPP).

[0077] In the present invention, the low elasticity resin layer may contain components other than the polyethylene resin, so long as the above conditions are satisfied.

[0078] Polyethylene resin has a lower melting point than polypropylene resin, but it is a polymer whose molecules cross-link when heat is repeatedly applied. When exposed to high temperatures for long periods of time, such as outdoors in the hot sun when the temperature of the steel material rises to 40-80°C, its molecules are less likely to break, and it has better long-term heat resistance than polypropylene resin. Furthermore, polyethylene resin has high melt tension, flexibility, resistance to deformation, resistance to whitening when deformed, and excellent cold resistance. Polyethylene resin also has a higher density than polypropylene resin, and is highly resistant to external moisture and polar solvents contained in adhesives.

[0079] In the present invention, linear low density polyethylene (LLPE) means a copolymer of ethylene and an α-olefin having about 4 to 20 carbon atoms, and specific examples of the branched side chain composed of an α-olefin include various comonomers such as butene-1, hexene-1, 4-methylpentene-1, octene-1, decene-1, tetracene-1, and octadecene-1. Two or more of these α-olefins may be used in combination. In addition, when an α-olefin having about 4 to 20 carbon atoms is used as a comonomer, propylene may be further used as a comonomer.

[0080] Any linear low-density polyethylene (LLPE) can be used as long as it can keep the MFR, density, and tensile modulus within the preferred ranges described below. Among them, linear low-density polyethylene having at least one side chain of butene-1, hexene-1, or octene-1 is preferred because it has appropriate flexibility, and hexene-1 and octene-1 are particularly preferred because they have excellent solvent resistance.

[0081] There are no limitations on the method for producing linear low density polyethylene (LLPE), and any known method for producing polyolefin resins can be used. Generally, however, it is preferable to produce it using a Ziegler catalyst, a metallocene catalyst, or the like.

[0082] The polyethylene resin in the present invention can also contain polyethylene resins other than linear low density polyethylene (LLPE). The polyethylene resins other than linear low density polyethylene (LLPE) are not limited, but specifically include high density polyethylene (HDPE), medium density polyethylene (MDPE), low density polyethylene (LDPE), etc. Here, low density polyethylene (LDPE) does not include the linear low density polyethylene (LLPE), and generally includes what is called high pressure low density polyethylene. The manufacturing method of high density polyethylene (HDPE), medium density polyethylene (MDPE), and low density polyethylene (LDPE) is not limited, and known methods can be adopted, but it is usually preferable to manufacture them using a Ziegler catalyst, a metallocene catalyst, etc.

[0083] Furthermore, in order to prevent moisture absorption and ultraviolet degradation of the high elasticity resin layer, various additives such as various elastomer components such as olefin-based elastomers such as ethylene-propylene copolymers, ethylene-butene copolymers, propylene-butene copolymers, ethylene-butene-propylene copolymers, and ethylene-propylene-diene copolymers, styrene-based elastomers, polyester-based elastomers, and polyamide-based elastomers, antioxidants, heat stabilizers, various plasticizers, light stabilizers, ultraviolet absorbers, neutralizing agents, lubricants, anti-fogging agents, anti-blocking agents, crosslinking agents, crosslinking assistants, colorants, flame retardants, and dispersants may be added to the low elasticity resin layer, within a range that does not impair the effects of the present invention.

[0084] The low elasticity resin layer in the present invention has a melt flow rate (MFR) of 0.1 g / 10 min to 20 g / 10 min and a density of 0.88 g / cm 3 More than 0.960g / cm 3 Hereinafter, the tensile modulus is preferably 100 MPa or more and 2000 MPa or less. The MFR, density and tensile modulus of the low elasticity resin layer are measured by the methods described in the Examples section below.

[0085] If the MFR of the low elasticity resin layer is more than 20g / 10min, the molecular weight of the polymer is low, the solvent resistance is reduced, and the weather resistance may be poor. The preferred MFR is 10g / 10min, more preferably 5g / 10min or less, and even more preferably 3g / 10min or less. The lower limit of the MFR is 0.1g / 10min or more because it is necessary to have a level that does not cause problems in film formation when forming a film by inflation molding, and it is particularly preferable that the MFR is 0.3g / 10min or more because it can maintain high-speed moldability in inflation molding.

[0086] In addition, the density of the low-elasticity resin layer is 0.88 g / cm 3 If the density is smaller than this, the solvent resistance and waterproof resistance may be deteriorated. In order to block moisture from the outside and to increase the resistance to solvents, it is preferable that the density of the low elasticity resin layer is relatively high, and the preferable lower limit of the density is 0.918 g / cm. 3 More preferably, 0.920 g / cm3 More preferably, it is 0.923 g / cm 3 The upper limit of density is 0.960 g / cm3 without impairing flexibility. 3 Below, especially 0.950g / cm 3 Taking into consideration the whitening resistance, the upper limit of the density is more preferably 0.945 g / cm 3 The following is the result. The means for setting the density of the low-elasticity resin layer within the above range is not limited, but examples include optimizing the polyethylene resin used in the low-elasticity resin layer, and, as described above, using polyethylene resin and resins other than polyethylene resin in combination and optimizing the blending ratio thereof.

[0087] The tensile modulus of the low elasticity resin layer is preferably 100 MPa or more, since too much flexibility can easily cause material destruction when an external force such as deformation is applied, and conversely, if it is too hard, it can easily become brittle and easily peel off from the metal foil in contact with it via the adhesive layer, so it is preferably less than 1500 MPa, and more preferably 1300 MPa or less. The tensile modulus of the low elasticity resin layer is particularly preferably 130 MPa or more and 1000 MPa or less, and particularly preferably 180 MPa or more and 900 MPa or less.

[0088] The above-mentioned values ​​of MFR, density, and tensile modulus refer to the properties of the resin constituting the low elasticity resin layer, and in the case where multiple polyethylene resins are used in combination as the polyethylene resin or where a resin other than polyethylene resin is contained, they refer to the values ​​as a resin composition.

[0089] In the present invention, in particular, the low elasticity resin layer is a layer mainly composed of linear low density polyethylene, and an acid-modified polyethylene resin layer having the above-mentioned suitable tensile modulus, density, MFR and melting point is used for the adhesive layer that is bonded to the high elasticity resin layer or metal foil, thereby making it possible to further increase strength and waterproof resistance.

[0090] The low elasticity resin layer may have a multi-layer structure, such as a laminate structure of a layer mainly composed of linear low density polyethylene and a random polypropylene layer or a block polypropylene layer, or a laminate structure of a layer mainly composed of linear low density polyethylene and a layer mainly composed of medium density polyethylene or high density polyethylene, or may further have a multi-layer laminate structure of about 3 to 5 layers.

[0091] The thickness of the low elasticity resin layer is preferably 3 μm or more and 80 μm or less, more preferably 10 μm or more and 70 μm or less, and particularly preferably 12 μm or more and 60 μm or less. If the thickness of the low elasticity resin layer is thinner than the lower limit, the water resistance may be insufficient and the corrosion prevention may be reduced. In addition, the flexibility may be insufficient and the workability may be poor. On the other hand, if the thickness is thicker than the upper limit, the handleability may be deteriorated. Here, the thickness of the low elasticity resin layer refers to the thickness of each low elasticity resin layer (per location). Here, one low elasticity resin layer is a layer that does not include an adhesive layer, for example, a layer adjacent to an adhesive layer, and if one low elasticity resin layer has a laminated structure of multiple layers, it corresponds to the total thickness of the layers.

[0092] The low elasticity resin layer is preferably provided with an uneven surface in order to improve adhesion with a pressure sensitive adhesive when it is attached to a material to be protected such as a steel material, or with an adhesive when it is attached to a high elasticity resin layer. In this case, the surface roughness Ra of the uneven surface is preferably about 0.1 to 1.2 μm, particularly about 0.2 to 0.8 μm. In addition, one or both sides of the low elasticity resin layer may be subjected to a treatment such as corona discharge treatment, plasma treatment, primer treatment, anchor coat treatment, etc., to improve adhesion to pressure-sensitive adhesives or adhesives and paintability when painting is applied. In this case, the contact angle of the treated surface with water is preferably 50° to 95°, and particularly preferably 55° to 90°.

[0093] [Light stabilizer] The anticorrosive laminate film of the present invention preferably has a layer containing a light stabilizer to improve light resistance and weather resistance. The light stabilizer may be contained in the adhesive layer, the protective layer, or both. In particular, the light stabilizer is preferably contained in a layer provided on the surface side of the metal foil, that is, on the opposite side to the protected material through the metal foil.

[0094] Although there is no particular limitation on the light stabilizer, a hindered amine light stabilizer (generally also written as HALS) is preferred, and a polymeric hindered amine light stabilizer is particularly preferred because of its excellent bleeding resistance. When an acid-modified PE resin, PE resin, or PP resin is used in the adhesive layer or protective layer, among the polymeric hindered amine light stabilizers, a polymeric hindered amine light stabilizer copolymerized with ethylene is preferred because it can significantly improve long-term weather resistance.

[0095] When a light stabilizer is incorporated into the protective layer or adhesive layer, there is no particular restriction on the amount of the light stabilizer incorporated; however, it is preferable for the content in the protective layer or adhesive layer to be between 0.01% by weight and 10% by weight in terms of weather resistance and waterproofing and corrosion resistance as an anticorrosive laminate film. A known ultraviolet absorbing agent may be used in combination with the light stabilizer. As the light stabilizer, commercially available products can be used, for example, Tinuvin Chimassorb (trade name) series manufactured by BASF, Adeka Stab (trade name) series manufactured by ADEKA, etc., which can be appropriately selected and used from those corresponding to the above.

[0096] [Layer structure of anticorrosive laminate film] The anticorrosive laminate film of the present invention is characterized by having a metal foil and an adhesive layer made of a thermoplastic heat-adhesive resin laminated on one or both sides of the metal foil. There are no particular restrictions on the configuration of the other layers as long as the configuration is as described above. For example, as shown in FIG. 1, anticorrosive laminate film 10 (10A) may be formed by laminating low-elasticity resin layers 1 (1a, 1b) on both sides of metal foil 3 via adhesive layers 2 (2a, 2b).

[0097] As shown in FIG. 2, a high elasticity resin layer 4 and a low elasticity resin layer 1 (1a) may be laminated on both sides of a metal foil 3 via adhesive layers 2 (2a, 2b) to form a corrosion-resistant laminate film, or a low elasticity resin layer 1 (1b, 1c) may be laminated on the outside of the metal foil 3 via adhesive layers 2 (2c, 2d) to form an integrated flexible corrosion-resistant laminate film.

[0098] Furthermore, as shown in FIG. 3, it may be an anticorrosive laminate film 10 (10C) in which an adhesive layer 2 is attached only to one surface of a metal foil 3.

[0099] In either case, it is preferable to have at least one adhesive layer 2 on at least the front side of the metal foil 4, which is the side opposite to the side that is adhered to the protected material, from the standpoint of long-term durability and weather resistance, but the adhesive layer 2 may also be attached to the side that is adhered to the protected material.

[0100] In the corrosion-resistant laminate film of the present invention, the adhesive layer, metal foil, high elasticity resin layer, and low elasticity resin layer may each be within the preferred thickness ranges described above, and there is no particular restriction on their total thickness. However, in order to ensure the necessary thickness of each layer and effectively obtain each function, the lower limit of the total thickness of the corrosion-resistant laminate film of the present invention is preferably 30 μm or more, more preferably 45 μm or more, and particularly preferably 50 μm or more, as this makes it less likely to tear. On the other hand, from the viewpoint of preventing the anticorrosive laminate film from becoming excessively thick and becoming highly rigid, which would impair workability, etc., the upper limit of the total thickness of the anticorrosive laminate film of the present invention is preferably 250 μm or less, and more preferably 200 μm or less.

[0101] [Other Processing] The outer surface of the anticorrosive laminate film (the surface opposite to the surface to which the steel material is attached) may be painted (not shown) or coated to enhance the anticorrosive effect. For example, a weather-resistant coating layer may be formed to improve water resistance and weather resistance. In order to enhance wettability with respect to adhesives or bonding agents used for attaching the film to materials to be protected, such as paint or steel materials, the film may be subjected to a surface treatment so that the contact angle with water is 50° or more and 100° or less.

[0102] Furthermore, when spraying paint on the outside of the anticorrosive laminate film or applying an adhesive to the inside, solvent resistance is required, so it is preferable to provide a hydrophobic low-elasticity resin layer with excellent solvent resistance, but good surface wettability is also important. Therefore, a primer may be applied, or as described above, the surface of the low-elasticity resin layer may be made uneven, or the outer surface of the anticorrosive laminate film may be subjected to surface treatment such as corona discharge treatment, plasma treatment, or flame treatment to improve adhesion to the adhesive or paint.

[0103] On the other hand, rather than surface wettability, giving the surface some degree of unevenness can suppress a phenomenon known as blocking, which occurs when films stick to each other after various corona treatments or plasma treatments to impart adhesion to surface paints, coatings, and adhesives, and this can be preferable in terms of workability and adhesion to adhesives, glues, and paints.

[0104] The surface roughness Ra of the anticorrosive laminate film of the present invention is preferably 0.03 to 1.2 μm, and more preferably 0.12 to 0.8. It is also possible to share appropriate wettability and appropriate unevenness in an appropriate combination.

[0105] [Manufacturing method of anticorrosive laminate film] There are no particular limitations on the method for manufacturing the anticorrosive laminate film of the present invention, but at least with regard to lamination of the metal foil and adhesive layer, preferred methods include a method in which the adhesive layer is first formed into a film by a T-die molding method or an inflation molding method, and then the metal foil and the formed adhesive layer are heated and bonded together by a thermal lamination method, a method in which the adhesive layer is directly attached to the metal foil by an extrusion lamination method, or a method in which a heated and melted adhesive layer is extruded and laminated between the protective layer film and the metal foil, thereby heating and melting the adhesive layer directly to the metal foil and bonding them together by a sand lamination method.

[0106] [Anti-corrosion tape] The anticorrosive laminate film of the present invention can be coated with a pressure sensitive adhesive or a bonding agent to form an anticorrosive tape, or a so-called double-sided tape made of a film or sheet-like material impregnated with a pressure sensitive adhesive can be attached to the anticorrosive laminate film of the present invention to form an anticorrosive tape. With such a configuration, it is possible to improve the long-term water resistance, durability, and workability of the anticorrosive tape.

[0107] In this case, it is preferable to use an adhesive having properties such that the adhesive strength is moderately low, particularly at the initial stage of lamination, and that the adhesive strength improves after hardening due to humidity, as an anticorrosive tape and to adhere it to the anticorrosive laminate film of the present invention, which is the anticorrosive substrate. In addition, the anticorrosive laminate film needs to have appropriate elasticity and thickness in order to absorb the uneven surfaces of the materials to be protected, such as steel, and to alleviate the stress applied during lamination and the stress from external impacts, thereby preventing damage to the anticorrosive laminate film for a long period of time. From this viewpoint, it is preferable to use a double-sided tape having a base material of paper, nonwoven fabric, cotton fabric, polyethylene or acrylic foam impregnated with an acrylic adhesive attached to an anticorrosive laminate film as an anticorrosive tape.

[0108] Figures 1 to 3 show anti-corrosion tapes 20 (20A, 20B, 20C) each formed by adhering release paper or film 6 to anti-corrosion laminate films 10 (10A, 10B, 10C) using an adhesive layer 5 made of a moisture-curing adhesive (which may be double-sided tape).

[0109] The thickness of the adhesive layer 5 or the double-sided tape is preferably 0.1 mm or more and 2 mm or less. If it is thicker than this, flexibility may be lost and workability may be deteriorated. On the other hand, if it is thinner than this, conformability to the unevenness of the adherend may be deteriorated and adhesive strength may be insufficient. The thickness of the adhesive layer 5 or the double-sided tape is more preferably 0.15 mm or more and 1.5 mm or less, and particularly preferably 0.20 mm or more and 1.2 mm or less.

[0110] The modulus of elasticity of the adhesive layer 5 or the double-sided tape should also be appropriately low, and it is preferable to use an adhesive double-sided tape in which an acrylic adhesive is impregnated into an acrylic foam having a tensile modulus of elasticity of 100 MPa or less. EXAMPLES

[0111] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples as long as it does not depart from the gist of the present invention.

[0112] [Evaluation method] The materials used in the following examples and comparative examples and the evaluation methods for the produced anticorrosive laminate films and anticorrosive tapes are as follows.

[0113] <Contact angle with water> The contact angle of the sample surface with water was measured using an automatic contact angle meter (product name: DROPMASTER, manufactured by Kyowa Interface Science Co., Ltd.), and the average value of the measured values ​​at five points was used.

[0114] <Surface roughness> Using a Keyence Corporation ultra-deep shape measuring microscope (product name "VK8500"), the surface roughness Ra of an area of ​​40 μm x 40 μm was measured at four points under the measurement conditions of 100x lens, pitch 0.01 μm, AUTO shutter speed, and gain 835, and the average value was taken as the measured surface roughness.

[0115] <Tensile modulus> The tensile modulus of elasticity of a resin or resin composition is a value measured on a 15 mm wide rectangular sample at a chuck distance of 100 mm using a Tensilon type tensile tester at 1 mm / min in accordance with ISO1184-1970.

[0116] <MFR(メルトフローレート)> The values ​​for PE were measured at 190°C and a load of 2.16 kgf in accordance with the JIS K 7210A method. For PP, the values ​​were measured at 230°C and a load of 2.16 kgf according to the JIS K 7210 method. For ETFE, the measurements are based on the ASTM D-1238 method.

[0117] <density> The density of the acid-modified LLPE, RPP, LLPE, and LDPE was measured by the JIS K7112A method (underwater displacement method), and that of the acid-modified ETFE was measured by the ASTM D792 method.

[0118] <Melting point> Based on DSC (differential scanning calorimetry) measurement. Using SSC-5200 (product name) manufactured by Seiko Denshi Kogyo Co., Ltd., the sample was heated at a heating rate of 10° C. / min, and the crystal melting peak temperature was taken as the melting point.

[0119] <Adhesive strength between metal foil and adhesive layer> The anticorrosive laminate film was cut to 15mm x 50mm, and the metal foil and adhesive layer were peeled off by 20mm to prepare a test piece. Using an Imada tensile tester, the interface between the metal foil and adhesive layer was peeled off by 30mm at a tensile speed of 50mm / min, and the minimum value was taken as the measured value of adhesive strength. The average of the minimum values ​​of the three samples was taken as the measurement result.

[0120] <Puncture strength> A test piece was prepared by cutting a piece of anticorrosive laminate film to 50mm x 100mm. Using an Imada tensile tester, the test piece was fixed between a presser plate with a 20mm diameter opening in the center and a stand, and a needle with a diameter of 1mm and a semicircular tip radius of 0.5mm was pierced at a piercing speed of 50mm / min to measure the breaking load when the needle penetrated. The average value of three samples was used as the measurement result.

[0121] <Accelerated hot water resistance test> A pressure cooker test was conducted as an accelerated test for the humidity resistance of anticorrosive laminate films. A high-temperature, high-density water vapor environment was created in the test tank, and the anticorrosive laminate film was left at 120°C and 100% for 240 hours (equivalent to 15 years of exposure at 40°C and 90%), after which the film was removed. After this accelerated hot water resistance test, the puncture strength was measured and compared with the measured value before the accelerated hot water resistance test to determine long-term water resistance.

[0122] <Accelerated weather resistance test> Using a super xenon weather meter, anticorrosive laminate film was measured at 180W / m 2 After 200 hours of exposure (corresponding to approximately 6 months of outdoor exposure), the film was removed. The puncture strength was measured after this accelerated weather resistance test, and compared with the measured value before the accelerated weather resistance test to determine long-term weather resistance.

[0123] <Overall rating> The overall evaluation of the anticorrosive laminate film was based on the following criteria. ◯: Both the puncture strength after the accelerated hot water resistance test and the puncture strength after the accelerated weather resistance test are 3N or more. △: Both the puncture strength after the accelerated hot water resistance test and the puncture strength after the accelerated weather resistance test are 2N or more and less than 3N. ×: The puncture strength after the accelerated hot water resistance test and the puncture strength after the accelerated weather resistance test are less than 2N.

[0124] <Overall evaluation of anticorrosion tape (peel strength)> The overall evaluation of the anticorrosion tape was made by adding the peel strength of the anticorrosion tape to the overall evaluation of the anticorrosion film described above. The anticorrosion tape was peeled off by applying it to a 1mm thick SUS430 plate, and then leaving it at 23°C and 50% for 24 hours (initial) and after conditioning at 45°C and 75% for 20 hours and leaving it at 23°C and 50% for 48 hours (after humidity curing). The peel strength was measured using a T-type peel strength test, and the humidity curing property was evaluated. Specifically, test pieces cut into 15 mm wide strips were used from each sample, and the interface between the SUS plate and the adhesive side of the corrosion protection tape was measured using Orientec's tensile testing machine "STA1225" at a tensile speed of 50 mm / min, peeling it off for 1 cm, and the maximum load during this peeling was recorded as the peel strength. The peel strength as an anticorrosive tape was judged according to the following criteria based on the measured values ​​of the initial peel strength and the peel strength after humid curing. ○: The value obtained by dividing the peel strength after humidity curing by the initial peel strength is more than 1.2 times ×: Does not meet the above requirements

[0125] [Physical properties of resin] In the examples and comparative examples, the properties of the resins used in the adhesive layer, the high elasticity resin layer, and the low elasticity resin layer are as shown in Table 1 below.

[0126] [Table 1]

[0127] [Materials of each layer] The constituent materials of each layer used in the production of the anticorrosive laminate film and anticorrosive tape in the Examples and Comparative Examples are as follows.

[0128] <High elastic resin layer> Ny-15: Biaxially oriented polyamide (Ny) film produced by the tubular method (thickness: 15 μm, tensile modulus: 2300 MPa, surface roughness Ra: 0.04 μm, both sides corona treated) Ny-25: Biaxially oriented polyamide (Ny) film produced by the tubular method (thickness: 25 μm, tensile modulus: 2300 MPa, surface roughness Ra: 0.04 μm, both sides corona treated)

[0129] <Light stabilizer> Polymeric hindered amine light stabilizers copolymerized with ethylene

[0130] <Weather-resistant coating agent> Weather-resistant acrylic coating agent containing 1% by weight of a polymeric hindered amine light stabilizer

[0131] <Adhesive> Dry adhesive 4: A layer made by applying a two-liquid mixture of aromatic polyester and polyisocyanate dry lamination adhesive to a thickness of 4 μm and drying.

[0132] <Metal foil> AL-40: 40μm thick JIS A8079H-O material (soft aluminum foil containing 1.0% iron by weight) with boehmite treatment on both sides The boehmite treatment was carried out by immersing the aluminum foil in boehmite treatment water (deionized water with 0.5% by weight of triethanolamine added) at 95°C for 1 minute to form a boehmite needle crystal film with a thickness of 0.25 μm. The contact angle of the film surface with water was 15°. AL-25: Untreated JIS 1N30H-O material (soft aluminum foil containing 0.4% by weight of iron) with a thickness of 25 μm. The contact angle of the untreated surface with water was 90°. AL-9: Untreated JIS 8021H-O material (soft aluminum foil containing 1.3% by weight of iron) with a thickness of 9 μm. The contact angle of the untreated surface with water was 90°. SUS-10: 10μm thick untreated SUS304

[0133] <Double-sided tape> Double-sided tape A: Double-sided tape made of 0.25 mm thick acrylic foam impregnated with acrylic adhesive (3M VHB tape, product name Y4914, tensile modulus: 10 MPa or less) Double-sided tape B: Double-sided tape made of 0.4 mm thick acrylic foam impregnated with acrylic adhesive (3M VHB tape, product name Y4920, tensile modulus: 10 MPa or less)

[0134] [Example 1] <Preparation of film for bonding on the front side> A material (for the adhesive layer) was dry-blended with 100 parts by weight of acid-modified LLPE and a light stabilizer concentration of 1% by weight, and a material (for the low-elasticity resin layer) was dry-blended with 95 parts by weight of LLPE and 5 parts by weight of LDPE and a light stabilizer concentration of 1% by weight, respectively, and these were co-extrusion blown film molded to produce the following two-layer film IA. Total thickness: 80μm Acid-modified LLPE layer (adhesive layer) thickness: 20 μm LLPE layer (for low elasticity resin layer) thickness: 60μm Surface roughness Ra: 0.3 μm

[0135] <Preparation of film for bonding to the protected material> An acid-modified LLPE (for the adhesive layer) that did not contain any light stabilizers and a material that was a dry blend of 95 parts by weight of LLPE and 5 parts by weight of LDPE (for the low-elasticity resin layer) were coextruded by inflation molding to produce a two-layer film IB as shown below. Total thickness: 50μm Acid-modified LLPE layer (adhesive layer) thickness: 12 μm LLPE layer (for low elasticity resin layer) thickness: 38μm Surface roughness Ra: 0.3 μm

[0136] <Production of anticorrosive laminate film> Two-layer films IA and IB were attached to both sides of AL-40 by thermal lamination, with the acid-modified LLPE layer side facing the AL-40 side, to obtain a five-layer laminate film with a total thickness of 170 μm. The surface roughness of the roll and release film during thermal lamination was adjusted so that the surface roughness of this laminated film was Ra 0.45 μm on both sides. Both sides of this laminated film were subjected to plasma treatment to produce an anticorrosive laminated film with a water contact angle of 80° and a surface roughness Ra of 0.45 μm on the plasma-treated surface of the LLPE layer side. The adhesive strength between the metal foil and adhesive layer of this anticorrosive laminate film was 13 N / 15 mm on the surface to be bonded to the front side, and 11 N / 15 mm on the surface to be bonded to the material to be protected. This anticorrosive laminate film was subjected to an accelerated hot water resistance test and an accelerated weather resistance test, and the puncture strength was measured before and after the tests.

[0137] Furthermore, double-sided tape A was applied to this anticorrosive laminate film to prepare an anticorrosive tape, and the humidity curing property was evaluated. The results are shown in Table 2.

[0138] [Example 2] <Preparation of films for bonding the front side and the protected material side> A material (for the adhesive layer) was dry-blended by mixing 100 parts by weight of acid-modified LLPE with a light stabilizer at a concentration of 1% by weight, and a material (for the low-elasticity resin layer) was dry-blended by mixing 95 parts by weight of LLPE and 5 parts by weight of LDPE with a light stabilizer at a concentration of 1% by weight, and a film was produced by co-extrusion inflation molding to obtain a two-layer film II as shown below. Total thickness: 50μm Acid-modified LLPE layer (adhesive layer) thickness: 12 μm LLPE layer (for low elasticity resin layer) thickness: 38μm Surface roughness Ra: 0.3 μm

[0139] <Production of anticorrosive laminate film> Two-layer film II was attached to both sides of AL-25 by thermal lamination so that the acid-modified LLPE layer side faced the AL-25 side, to obtain a five-layer laminate film with a total thickness of 125 μm. The surface roughness of the roll and release film during thermal lamination was adjusted so that the surface roughness of this laminated film was Ra 0.4 μm on both sides. Both sides of this laminated film were subjected to plasma treatment to produce an anticorrosive laminated film with a water contact angle of 80° and a surface roughness Ra of 0.4 μm on the plasma-treated surface of the LLPE layer side. The adhesive strength between the metal foil and the adhesive layer of this anticorrosive laminate film was 11 N / 15 mm on both the front side bonding surface and the side bonding surface to the protected material. This anticorrosive laminate film was subjected to an accelerated hot water resistance test and an accelerated weather resistance test, and the puncture strength was measured before and after the tests.

[0140] In addition, double-sided tape B was applied to this anticorrosive laminate film to prepare an anticorrosive tape, and the humidity curing property was evaluated. The results are shown in Table 2.

[0141] [Example 3] As the adhesive layer film, an acid-modified ETFE film having a thickness of 50 μm was produced by a T-die molding method using acid-modified ETFE. Next, an acid-modified ETFE film was laminated to one side (the surface to be laminated) of the AL-25 by thermal lamination to obtain an anticorrosive laminate film with a total thickness of 75 μm. The surface roughness of the roll and release film during thermal lamination was adjusted so that the surface roughness of the acid-modified ETFE side of this anticorrosive laminate film was Ra 0.15 μm. The adhesive strength between the metal foil and the adhesive layer of this anticorrosive laminate film was 6 N / 15 mm. This anticorrosive laminate film was subjected to an accelerated hot water resistance test and an accelerated weather resistance test, and the puncture strength was measured before and after the tests. In addition, double-sided tape B was applied to the bonding surface of this anticorrosive laminate film facing the protected material to prepare an anticorrosive tape, and the humidity curing property was evaluated. The results are shown in Table 2.

[0142] [Example 4] <Preparation of base film> A 30 μm-thick single-layer inflation film of acid-modified LLPE was used as the adhesive layer film, and Ny-15 was used as the protective layer film. The two films were laminated by thermal lamination to form a layered structure of Ny-15 / acid-modified LLPE film / AL-9 / acid-modified LLPE film / Ny-15 to form the substrate film.

[0143] <Preparation of outer layer film> The following outer layer film was produced by co-extrusion inflation molding of acid-modified LLPE (for adhesive layer) and a material made by dry blending 95 parts by weight of LLPE and 5 parts by weight of LDPE (for low-elasticity resin layer). Total thickness: 30μm Acid-modified LLPE layer (adhesive layer) thickness: 10 μm LLPE layer (for low elasticity resin layer) thickness: 20μm

[0144] <Production of anticorrosive laminate film> The outer layer films were attached to both sides of the base film by thermal lamination, with the acid-modified LLPE layer side facing inward, to obtain a nine-layer laminate film with a total thickness of 159 μm. The surface roughness of the roll and release film during thermal lamination was adjusted so that the surface roughness of this laminated film was Ra 0.4 μm on both sides. Both sides of this laminated film were subjected to plasma treatment, so that the contact angle with water of the plasma-treated surface on the LLPE layer side was 80° and the surface roughness Ra was 0.4 μm. Next, a weather-resistant coating agent was applied to a thickness of 10 μm on the LLPE layer on the surface side to create a corrosion-resistant laminate film with a total thickness of 169 μm. The adhesive strength between the metal foil and the adhesive layer of this anticorrosive laminate film was 12 N / 15 mm on both the front side bonding surface and the side bonding surface to the protected material. This anticorrosive laminate film was subjected to an accelerated hot water resistance test and an accelerated weather resistance test, and the puncture strength was measured before and after the tests. In addition, double-sided tape B was applied to this anticorrosive laminate film to prepare an anticorrosive tape, and the humidity curing property was evaluated. The results are shown in Table 2.

[0145] [Example 5] An acid-modified RPP was used as the adhesive layer resin, and an unstretched PP film (thickness 25 μm) was used as the protective layer film. The acid-modified RPP was extruded onto both sides of AL-25 using the sand lamination method, and the PP film was bonded to obtain a five-layer laminate film as shown below. Thickness of each acid-modified RPP layer (adhesive layer): 20 μm Each PP layer (for low elasticity resin layer) thickness: 25μm Total thickness: 115μm The PP film was selected so that the surface roughness of this laminated film would be Ra 0.25 μm on both sides. Both sides of this laminated film were subjected to plasma treatment, so that the plasma-treated surface on the PP layer side had a contact angle with water of 90° and a surface roughness Ra of 0.25 μm. Furthermore, a weather-resistant coating agent was applied to a thickness of 10 μm on the PP layer on the surface side to create an anticorrosive laminate film with a total thickness of 125 μm. The adhesive strength between the metal foil and the adhesive layer of this anticorrosive laminate film was 8 N / 15 mm on both the front side bonding surface and the side bonding surface to the protected material. This anticorrosive laminate film was subjected to an accelerated hot water resistance test and an accelerated weather resistance test, and the puncture strength was measured before and after the tests. In addition, double-sided tape B was applied to this anticorrosive laminate film to prepare an anticorrosive tape, and the humidity curing property was evaluated. The results are shown in Table 2.

[0146] [Example 6] Except for using SUS-10 instead of AL-25, lamination was performed in the same manner as in Example 2 to obtain an anticorrosive laminate film having a total thickness of 110 μm. The adhesive strength between the metal foil and the adhesive layer of this anticorrosive laminate film was 11 N / 15 mm on both the front side bonding surface and the side bonding surface to the protected material. This anticorrosive laminate film was subjected to an accelerated hot water resistance test and an accelerated weather resistance test, and the puncture strength was measured before and after the tests. In addition, double-sided tape B was applied to this anticorrosive laminate film to prepare an anticorrosive tape, and the humidity curing property was evaluated. The results are shown in Table 2.

[0147] [Example 7] Ny-25 was used as a film for a high-elasticity resin layer, and was attached to one surface (front bonding surface) of AL-40 via a dry adhesive 4 by dry lamination. A two-layer film IB prepared in the same manner as the lamination film for the protected material in Example 1 was laminated to the other side of AL-40 (the lamination surface for the protected material) by thermal lamination so that the acid-modified LLPE side was the AL-40 side, obtaining a five-layer laminate film with a total thickness of 119 μm. The surface roughness of the roll and the release film during the thermal lamination was adjusted so that the surface roughness of this laminated film was Ra: 0.45 μm. The LLPE layer side of this laminated film, which is to be attached to the protected material, was subjected to plasma treatment to produce an anticorrosive laminated film with a water contact angle of 80° and a surface roughness Ra of 0.45 μm. The adhesive strength between the metal foil and the adhesive layer of this anticorrosive laminate film was 2.5 N / 15 mm on the surface to be bonded to the front side, and 11 N / 15 mm on the surface to be bonded to the material to be protected. This anticorrosive laminate film was subjected to an accelerated hot water resistance test and an accelerated weather resistance test, and the puncture strength was measured before and after the tests. In addition, double-sided tape B was applied to this anticorrosive laminate film to prepare an anticorrosive tape, and the humidity curing property was evaluated. These results are shown in Table 2.

[0148] [Comparative Example 1] A material obtained by dry blending 95 parts by weight of LLPE and 5 parts by weight of LDPE was subjected to single-layer inflation molding to obtain a single-layer film having a thickness of 30 μm. Both sides of this film were subjected to plasma treatment to prepare a film for a low elasticity resin layer having a contact angle with water of 80° and a surface roughness Ra of 0.25 μm. This film for low elasticity resin layer was attached to both sides of AL-25 via dry adhesive 4 by dry lamination to obtain a five-layer laminate film (total thickness: 93 μm) for corrosion prevention. The adhesive strength between the metal foil of this anticorrosive laminate film and the dry adhesive was 2.5 N / 15 mm on both the front side bonding surface and the side bonding surface to the material to be protected. This anticorrosive laminate film was subjected to an accelerated hot water resistance test and an accelerated weather resistance test, and the puncture strength was measured before and after the tests. In addition, double-sided tape B was attached to this anticorrosive laminate film to form an anticorrosive tape. The results are shown in Table 2.

[0149] [Table 2]

[0150] [Consideration] From Table 2, we can see the following: In Examples 1 to 6, an adhesive layer made of a thermoplastic thermal adhesive resin is attached to at least the outer surface side (the side opposite the material to be protected) of the metal foil, thereby obtaining a corrosion-resistant laminate film that can withstand accelerated hot water resistance tests and accelerated weather resistance tests. In addition, in Examples 1, 2, 4, 5, and 6, although polyolefin-based materials are used, a light stabilizer is blended into at least one layer, resulting in an anticorrosive laminate film that is more capable of withstanding accelerated hot water resistance tests and accelerated weather resistance tests.

[0151] In Example 3, by using acid-modified ETFE as the thermoplastic thermal adhesive resin in the adhesive layer, an anticorrosive laminate film that can withstand accelerated hot water resistance tests and accelerated weather resistance tests is obtained without the addition of a light stabilizer.

[0152] Furthermore, as seen in Examples 1, 2, 3, 5, and 6, there are cases in which the puncture strength after the accelerated hot water resistance test is improved compared to the puncture strength before the test. This is presumably because the application of heat to the adhesive layer causes it to be more firmly thermally bonded to the metal foil, and because the ethylene component contained in the thermoplastic thermal adhesive resin undergoes crystallization and crosslinking due to heat and moisture, thereby improving rigidity. This is thought to be the effect of using the thermoplastic thermal adhesive resin according to the present invention as an adhesive layer. In Example 4, the puncture strength after the accelerated hot water resistance test was lower than the puncture strength before the test, which is believed to be due to hydrolysis of the Ny resin. However, since the adhesive layer made of the thermoplastic heat-bonding resin is bonded to the metal foil, the product is able to withstand the hot water resistance test.

[0153] In addition, in Example 7, an adhesive layer made of a thermoplastic thermal adhesive resin is not bonded to the surface side of the metal foil, but an adhesive layer made of a thermoplastic thermal adhesive resin is bonded to the metal foil on the side facing the protected material, so that the resin remains on the side facing the protected material, and the film can withstand accelerated hot water resistance tests and accelerated weather resistance tests to a certain extent. Although the long-term durability is somewhat inferior, it is considered to be at a level that can be used as long as it is not used under harsh conditions such as high temperature and high humidity.

[0154] In contrast, in Comparative Example 1, since an adhesive layer made of a thermoplastic thermal adhesive resin is not bonded to the metal foil, the film cannot withstand the accelerated hot water resistance test or the accelerated weather resistance test, and the puncture strength decreases significantly after the test, resulting in significantly inferior long-term durability. [Explanation of symbols]

[0155] 1(1a,1b,1c) Low elasticity resin layer 2(2a,2b,2c,2d) Adhesive layer 3 Metal foil 4 High elastic resin layer 5 Adhesive layer 6 Release paper or release film 10(10A, 10B, 10C) Anticorrosive laminate film 20(20A,20B,20C) Anticorrosive tape

Claims

1. A corrosion-preventive laminate film comprising a metal foil and an adhesive layer containing a light stabilizer laminated on both sides of the metal foil, the adhesive layer being made of a thermoplastic heat-adhesive resin, the heat-adhesive resin being a resin that exhibits adhesive properties as defined below. <Definition of Adhesion> The thermal adhesive resin is heated to above its melting point to be melted and adhered to the metal foil, and then exhibits an adhesive strength of 3N / 15mm or more when measured by a T-peel test method in an environment of normal temperature and humidity of 23°C and 50%.

2. A corrosion-resistant laminate film comprising a metal foil, a protective layer, and an adhesive layer containing a light stabilizer that bonds the metal foil and the protective layer, the adhesive layer being made of a thermoplastic heat-adhesive resin, and the heat-adhesive resin being a resin that exhibits adhesive properties as defined below. <Definition of Adhesion> The thermal adhesive resin is heated to above its melting point to be melted and adhered to the metal foil, and then exhibits an adhesive strength of 3N / 15mm or more when measured by a T-peel test method in an environment of normal temperature and humidity of 23°C and 50%.

3. The anticorrosive laminate film according to claim 1 or 2, characterized in that the thermoplastic thermal adhesive resin is mainly composed of an acid-modified polyolefin resin and / or an acid-modified fluororesin, and the thickness of the adhesive layer is 2 to 100 μm.

4. 4. The anticorrosive laminate film according to claim 1, wherein the light stabilizer is a polymeric hindered amine light stabilizer.

5. The anticorrosive laminate film according to any one of claims 1 to 4, characterized in that the metal foil is an aluminum foil or SUS foil having a thickness of 6 to 100 μm, and the iron content of the aluminum foil is 0.3% by weight or more and 1.7% by weight or less.

6. A corrosion-resistant laminate film as described in claim 2, wherein the protective layer is the outermost layer.

7. A corrosion-resistant laminate film as described in claim 2 or 6, wherein the protective layer is a layer that blocks water from the outside.

8. An anti-corrosion tape having a metal foil and an adhesive layer laminated on one or both sides of the metal foil, the adhesive layer being made of a thermoplastic thermal adhesive resin, the thermal adhesive resin being a resin exhibiting adhesive properties as defined below, characterized in that a moisture-curing adhesive layer is provided on a corrosion-resistant laminate film. <Definition of Adhesion> The thermal adhesive resin is heated to above its melting point to be melted and adhered to the metal foil, and then exhibits an adhesive strength of 3N / 15mm or more when measured by a T-peel test method in an environment of normal temperature and humidity of 23°C and 50%.

9. An anti-corrosion tape having a metal foil and an adhesive layer laminated on one or both sides of the metal foil, the adhesive layer being made of a thermoplastic thermal adhesive resin, the thermal adhesive resin being a resin exhibiting adhesive properties as defined below, and characterized in that the anti-corrosion laminate film is laminated with a double-sided tape made of acrylic foam impregnated with an acrylic adhesive. <Definition of Adhesion> The thermal adhesive resin is heated to above its melting point to be melted and adhered to the metal foil, and then exhibits an adhesive strength of 3N / 15mm or more when measured by a T-peel test method in an environment of normal temperature and humidity of 23°C and 50%.

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