Anti-edible adhesion tape

Abstract

To provide an anti-corrosion adhesive tape having both excellent anti-corrosion properties and good adhesiveness.SOLUTION: An anti-corrosion adhesive tape 10 includes a metal layer 15, and an adhesive layer 11 disposed on at least one surface of the metal layer 15. The metal layer 15 is a layer of metal with a lower redox potential than that of iron, and the adhesive layer 11 contains an anisotropic conductive material 13.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an anticorrosive adhesive tape, and more specifically, to an anticorrosive adhesive tape for preventing corrosion of iron or an alloy containing iron such as steel.

Background Art

[0002] In order to prevent corrosion of iron or an alloy containing iron such as steel, an anticorrosive paint containing a large amount of zinc is widely used. Zinc is a metal with a lower potential than iron and has a sacrificial anticorrosive effect, so it is known to have high anticorrosive properties. However, anticorrosion by paint requires a drying process etc. after application, which takes time for the work. For example, when performing local repairs in civil engineering and construction applications such as bridges, the work efficiency decreases. Also, anticorrosion by paint is likely to cause uneven work.

[0003] In view of the above situation, conventionally, efforts have been made to impart sacrificial anticorrosive properties to adhesive tapes etc. to improve workability. For example, Patent Document 1 discloses an anticorrosive member provided with a conductive adhesive layer containing a metal with a lower potential than iron and a conductive material other than that metal. Since the conductive adhesive layer of this anticorrosive member contains a conductive material other than the metal with a lower potential than iron in addition to the metal with a lower potential than iron, it is not necessary to contain a large amount of the metal with a lower potential than iron in order to exhibit good sacrificial anticorrosive properties. Therefore, this anticorrosive member can have good adhesiveness.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Although the adhesiveness of the anticorrosive member in Patent Document 1 is excellent, depending on the object to be protected against corrosion, the adhesiveness of the anticorrosive member described in Patent Document 1 may be insufficient. For this reason, an anticorrosive member with even better adhesiveness is desired. Therefore, an object of the present invention is to provide an adhesive tape for corrosion protection that has excellent corrosion protection properties and further has good adhesiveness.

Means for Solving the Problems

[0006] As a result of intensive studies, the present inventors have found that by using a metal with a lower potential than iron as the base material and incorporating an anisotropic conductive material into the adhesive layer to impart conductivity to the adhesive layer, the above problems can be solved, and the following present invention has been completed. That is, the present invention provides the following [1] to [9]. [1] An adhesive tape for corrosion protection comprising a metal layer and an adhesive layer provided on at least one surface of the metal layer, wherein the metal layer is a layer of a metal having a lower potential than iron, and the adhesive layer contains an anisotropic conductive material. [2] The adhesive tape according to [1] above, wherein the total light transmittance X per 1 μm thickness of the adhesive layer is 99.85% or less. [3] The adhesive tape for corrosion protection according to [1] or [2] above, wherein the aspect ratio of the anisotropic conductive material is 2 or more. [4] The adhesive tape for corrosion protection according to any one of [1] to [3] above, wherein the anisotropic conductive material is a carbon-based material. [5] The adhesive tape for corrosion protection according to [4] above, wherein the carbon-based material is carbon nanotubes. [6] The adhesive tape for corrosion protection according to any one of [1] to [5] above, wherein the resistance value of the adhesive layer is 1×10 8 ~1×10 14 Ω. [7] The adhesive tape for corrosion protection according to any one of [1] to [6] above, wherein the thickness of the adhesive layer is 20 μm or more. [8] The adhesive tape for corrosion protection according to any one of [1] to [7] above, wherein the metal layer is a zinc foil. [9] The anticorrosive edible adhesive tape according to any one of [1] to [8] above, wherein the thickness of the metal layer is 2.5 μm or more.

Advantages of the Invention

[0007] According to the present invention, it is possible to provide an anticorrosive edible adhesive tape having excellent anticorrosion properties and good adhesiveness.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0009] The anticorrosive edible adhesive tape of the present invention includes a metal layer and an adhesive layer provided on at least one surface of the metal layer. The metal layer is a layer of a metal having a lower potential than iron, and the adhesive layer contains an anisotropic conductive material. Thereby, the anticorrosive edible adhesive tape of the present invention can exhibit excellent anticorrosion properties with a small amount of conductive material blended, and as a result, the adhesiveness can be improved. Hereinafter, the anticorrosive edible adhesive tape of the present invention will be described in detail.

[0010] (Metal Layer) The metal layer in the anticorrosive edible adhesive tape of the present invention is a layer of a metal having a lower potential than iron. By attaching the anticorrosive edible adhesive tape of the present invention to an adherend, the metal layer is corroded instead, and the adherend can be protected from corrosion by so-called sacrificial corrosion protection. The metal layer is not particularly limited, but preferably a metal foil is used. Examples of metals having a lower potential than iron include cadmium, chromium, zinc, manganese, aluminum, and the like. Among these metals, from the viewpoint of corrosion resistance, zinc and aluminum are preferable, and zinc is more preferable. Therefore, it is more preferable that the metal layer is a zinc foil.

[0011] In addition, as the adherend, those containing iron or an alloy containing iron are used. Specific examples of the alloy containing iron include alloy steels such as nickel-chromium steel, nickel-chromium-molybdenum steel, chromium steel, chromium-molybdenum steel, and manganese steel, and various steel materials such as carbon steel. The adherend is not particularly limited, and examples include steel materials used in various civil engineering and construction applications, vehicle applications such as automobiles, railways, airplanes, and ships, various electrical products, and other metal members. Among them, steel materials used in civil engineering and construction applications are preferable.

[0012] <Thickness of the metal layer> The thickness of the metal layer is preferably 2.5 μm or more. When the thickness of the metal layer is 2.5 μm or more, the metal layer can sufficiently supply electrons due to the ionization of the metal in the metal layer to the adherend, and sufficient corrosion resistance of the anti-corrosion adhesive tape can be maintained. From the viewpoint of enhancing the corrosion resistance of the anti-corrosion adhesive tape, the thickness of the metal layer is more preferably 5 μm or more. Also, from the viewpoint of ensuring the flexibility of the anti-corrosion adhesive tape and improving the handleability of the anti-corrosion adhesive tape, the thickness of the metal layer is preferably 200 μm or less, and more preferably 100 μm or less.

[0013] (Adhesive layer) The adhesive layer contains an anisotropic conductive material. Thereby, even if the content of the conductive material in the adhesive layer is small, the electrons generated by the ionization of the metal in the metal layer can be efficiently supplied to the adherend. As a result, the anti-corrosion adhesive tape of the present invention has excellent corrosion resistance and good adhesiveness.

[0014] <Anisotropic conductive material> An anisotropic conductive material is a conductive material having anisotropy in shape. Examples of the anisotropic conductive material include fibrous conductive materials and flaky conductive materials. The anisotropic conductive material has a high aspect ratio. For example, the aspect ratio is 2 or more, preferably 5 or more, more preferably 10 or more, and even more preferably 500 or more. By setting the aspect ratio to 2 or more, even if the amount of the conductive material in the adhesive layer is small, it is possible to efficiently supply the electrons generated by the ionization of the metal in the metal layer to the adherend, and it becomes easier to achieve both excellent corrosion resistance and good adhesiveness. The upper limit of the aspect ratio is not particularly limited. Specifically, the aspect ratio is the ratio of the length in the major axis direction to the length in the minor axis direction of the anisotropic conductive material. In the case of a fibrous conductive material, it means fiber length / fiber diameter, and in the case of a flaky conductive material, it means the length in the major axis direction of the flaky conductive material / thickness. The lengths in the minor axis direction and the major axis direction of the anisotropic conductive material may be measured, for example, in an image obtained by observation with an electron microscope or an optical microscope. From the viewpoint that the anisotropic conductive material can effectively move the electrons generated by the ionization of the metal in the metal layer with a small content, it is preferably a fibrous conductive material.

[0015] From the viewpoints of the corrosion resistance and adhesiveness of the anticorrosive adhesive tape, the content of the anisotropic conductive material in the adhesive layer is preferably 0.001 to 4 parts by mass, more preferably 0.005 to 1 part by mass, and even more preferably 0.008 to 0.5 part by mass with respect to 100 parts by mass of the adhesive. By setting it within the above range, while ensuring high corrosion resistance, it is possible to prevent the adhesive strength of the adhesive layer from being reduced by the anisotropic conductive material. Also, when the adhesive layer is formed from an acrylic adhesive described later, the content of the anisotropic conductive material is preferably 0.001 to 1 part by mass, more preferably 0.005 to 0.5 part by mass, still more preferably 0.008 to 0.2 part by mass, and even more preferably 0.01 to 0.1 part by mass with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A) described later. When the content of the anisotropic conductive material is equal to or higher than these lower limits, the sacrificial corrosion resistance is likely to increase, and when the content of the anisotropic conductive material is equal to or lower than these upper limits, the adhesive strength is likely to improve.

[0016] When the anisotropic conductive material is a fibrous conductive material, its average fiber length is preferably 0.1 to 1000 μm, more preferably 10 to 500 μm. When the average fiber length is 0.1 μm or more, the anisotropic conductive materials are appropriately in contact with each other inside the adhesive layer, and it becomes easy to secure a conduction path for electrons generated by the ionization of the metal in the metal layer. On the other hand, when the average fiber length is 1000 μm or less, the handling of the anisotropic conductive material becomes even easier. Also, when the anisotropic conductive material is a fibrous conductive material, its average diameter is preferably 1 to 100 nm, more preferably 2 to 15 nm. The aspect ratio (average fiber length / average diameter) of the fibrous conductive material is preferably 10 to 100000, more preferably 500 to 30000. The above average fiber length and average diameter can be calculated by observing the anisotropic conductive material with a microscope. More specifically, for example, in an image obtained by observation with an electron microscope or an optical microscope, the fiber lengths and diameters of 50 arbitrary anisotropic conductive materials are measured, and the average value (arithmetic mean value) can be used as the average fiber length and average diameter.

[0017] Examples of the anisotropic conductive material include carbon-based materials, metal-based materials, metal oxide-based materials, and the like. Examples of carbon-based materials include carbon fibers such as PAN (polyacrylonitrile)-based carbon fibers, rayon-based carbon fibers, phenol-based carbon fibers, pitch-based carbon fibers, graphene, carbon nanotubes, carbon nanofibers, carbon nanocoils, flaky graphite, and the like. When the metal-based material is a single metal, it is preferably a metal having a lower potential than iron. If a metal having a higher potential than iron is used, electrons may flow from iron to the metal-based material, which may prevent electrons from moving from the metal layer to iron. Specific examples of the metal-based material include flaky aluminum, aluminum fibers, and the like. Examples of the metal oxide material include zinc oxide and the like. These conductive materials may be used alone or in combination of two or more.

[0018] Among these anisotropic conductive materials, from the viewpoint of improving the conductivity of the adhesive layer without impairing the adhesiveness, carbon-based materials are preferable, and among them, fibrous carbon-based materials such as carbon nanotubes, carbon nanofibers, and carbon fibers are more preferable, and carbon nanotubes are even more preferable. Carbon nanotubes are substances having a structure in which a graphite sheet with a hexagonal network arrangement of carbon atoms is wound cylindrically. Those wound in a single layer are called single-walled carbon nanotubes, and those wound in multiple layers are called multi-walled carbon nanotubes. In the present invention, the type of carbon nanotube is not particularly limited, and any of single-walled carbon nanotubes, multi-walled carbon nanotubes, and mixtures containing these at an arbitrary ratio may be used. Further, carbon nanotubes produced by various methods such as the arc discharge method, laser evaporation method, and chemical vapor deposition method (CVD method) can be used. Also, the preferred ranges of the average length, average diameter, and aspect ratio of the carbon nanotubes are the same as the average fiber length, average diameter, and aspect ratio described for the fibrous conductive material above. Note that the diameter of the carbon nanotube refers to the outer diameter in the case of single-walled carbon nanotubes, and the outer diameter of the outermost tube in the case of multi-walled carbon nanotubes.

[0019] The adhesive layer may contain, in addition to the anisotropic conductive material, a conductive material having no anisotropic shape (hereinafter referred to as a non-anisotropic conductive material) as long as the effects of the present invention are not impaired. The non-anisotropic conductive material is a conductive material having a low aspect ratio, for example, a conductive material having an aspect ratio of less than 2. However, from the viewpoint of increasing the adhesiveness while maintaining the excellent corrosion resistance of the anticorrosive adhesive tape, it is preferable that the adhesive layer does not contain a non-anisotropic conductive material.

[0020] The particle size of the non-anisotropic conductive material is preferably 1 to 200 μm. By setting the particle size of the non-anisotropic conductive material to 200 μm or less, it becomes easier to disperse the non-anisotropic conductive material in the adhesive layer while suppressing a decrease in the adhesiveness of the adhesive layer. By setting the particle size of the non-anisotropic conductive material to 1 μm or more, it becomes easier to improve the conductivity of the adhesive layer by the non-anisotropic conductive material. The above particle size is more preferably 5 to 100 μm. Note that in this specification, the particle size means the average particle size measured by the laser diffraction method.

[0021] Examples of the anisotropic conductive material include one or more selected from carbon-based materials, metal-based materials, metal oxide-based materials, ionic polymers, and conductive polymers. Examples of the carbon-based materials include carbon black, graphite, and acetylene black. Examples of the metal-based materials include noble metals having a potential higher than that of iron, such as gold, silver, copper, nickel, or alloys containing these, and base metals having a potential lower than that of iron, such as iron, cadmium, chromium, zinc, manganese, and aluminum. When a base metal is used as the metal-based material, sacrificial corrosion can be achieved even with the anisotropic conductive material. Examples of the metal oxide materials include indium tin oxide (ITO), antimony trioxide (ATO), fluorine-doped tin oxide (FTO), and zinc oxide. Examples of the conductive polymers include polyacetylene, polypyrrole, PEDOT (polyethylenedioxythiophene), PEDOT / PSS (a composite of polyethylenedioxythiophene and polystyrene sulfonic acid), polythiophene, polyaniline, poly(p-phenylene), polyfluorene, polycarbazole, polysilane, or derivatives thereof. Examples of the ionic polymers include sodium polyacrylate and potassium polyacrylate. The anisotropic conductive material may be used alone or in combination of two or more thereof.

[0022] <Adhesive> The adhesive layer is preferably formed by blending an anisotropic conductive material into an adhesive. In this specification, in the adhesive layer, components other than the anisotropic conductive material and the isotropic conductive material are defined as the adhesive. Examples of the adhesive used for the adhesive layer include acrylic adhesives, rubber adhesives, urethane adhesives, and silicone adhesives. These adhesives may be used alone or in combination. Among these, it is preferable to use an acrylic adhesive. When an acrylic adhesive is used, it is easy to improve the adhesive performance of the anticorrosive adhesive tape.

[0023] Next, the adhesive used for the adhesive layer will be described in more detail. <<Acrylic Adhesive>> An acrylic adhesive is an adhesive containing an acrylic polymer obtained by polymerizing a polymerizable monomer containing a (meth)acrylic acid alkyl ester monomer (A). In this specification, the term "(meth)acrylic acid alkyl ester" refers to a concept including both acrylic acid alkyl esters and methacrylic acid alkyl esters, and the same applies to other similar terms. Also, the term "polymerizable monomer" refers to a concept that includes not only compounds having no repeating units but also compounds copolymerizable with the (meth)acrylic acid alkyl ester monomer (A), such as the monomer of the olefin polymer (C) described later, which itself has repeating units.

[0024] [(Meth)acrylic acid alkyl ester monomer (A)] (Meth)acrylic acid alkyl ester monomer (A) is an ester of (meth)acrylic acid and an aliphatic alcohol, and an alkyl ester derived from an aliphatic alcohol having an alkyl group with preferably 2 to 14 carbon atoms, more preferably 4 to 10 carbon atoms, is preferred. When the carbon number of the alkyl group is within this range, the glass transition temperature (Tg) of the adhesive layer can be set within an appropriate temperature range, making it easier to adjust the adhesive properties of the adhesive layer.

[0025] As the specific (meth)acrylic acid alkyl ester monomer (A), for example, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, and tetradecyl (meth)acrylate can be mentioned. Among these, n-butyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and n-octyl (meth)acrylate are preferred, and n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, or a combination thereof is more preferred. The (meth)acrylic acid alkyl ester monomer may be used alone or in combination of two or more.

[0026] The structural unit derived from the (meth)acrylic acid alkyl ester monomer (A) constitutes the main component in the adhesive, and its content is generally 30% by mass or more, preferably 40% by mass or more, more preferably 45% by weight or more based on the total amount of the adhesive. Thus, increasing the content of the (meth)acrylic acid alkyl ester monomer (A) makes it possible to impart the desired adhesive force to the adhesive. In addition, since the content of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A) in the adhesive is substantially the same as the content of the (meth)acrylic acid alkyl ester monomer (A) in the adhesive composition described later, it can be represented by replacement. The same applies to components other than the (A) component, such as components (B) and (C) described below.

[0027] [Polar group-containing vinyl monomer (B)] In addition to the (meth)acrylic acid alkyl ester monomer (A), the polymerizable monomer preferably contains a polar group-containing vinyl monomer (B). The polar group-containing vinyl monomer (B) has a polar group and a vinyl group. By using the polar group-containing monomer (B) in the pressure-sensitive adhesive layer, it becomes easier to adjust the pressure-sensitive adhesive properties of the pressure-sensitive adhesive layer. Examples of the polar group-containing vinyl monomer (B) include vinyl carboxylates such as vinyl acetate, carboxylic acids containing a vinyl group such as (meth)acrylic acid and itaconic acid, and their anhydrides, vinyl monomers having a hydroxyl group such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, caprolactone-modified (meth)acrylate, polyoxyethylene (meth)acrylate, and polyoxypropylene (meth)acrylate, nitrogen-containing vinyl monomers such as (meth)acrylonitrile, N-vinylpyrrolidone, N-vinylcaprolactam, N-vinyl laurolactam, (meth)acryloylmorpholine, (meth)acrylamide, dimethyl (meth)acrylamide, N-methylol (meth)acrylamide, N-butoxymethyl (meth)acrylamide, and dimethylaminomethyl (meth)acrylate. Among these, carboxylic acids containing a vinyl group such as (meth)acrylic acid and itaconic acid, and their anhydrides are preferred, (meth)acrylic acid is more preferred, and acrylic acid is even more preferred. These polar group-containing vinyl monomers (B) may be used alone or in combination of two or more.

[0028] When using the polar group-containing vinyl monomer (B), the content of the structural unit derived from the polar group-containing vinyl monomer (B) in the pressure-sensitive adhesive is preferably 1 to 15 parts by mass, more preferably 2 to 12 parts by mass, and even more preferably 3 to 10 parts by mass with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A). By setting the content of the polar group-containing vinyl monomer (B) within such a range, it becomes easier to adjust the pressure-sensitive adhesive properties of the pressure-sensitive adhesive layer to an appropriate range.

[0029] [Olefin polymer (C)] The polymerizable monomer preferably further contains an olefin polymer (C) having a polymerizable bond at its terminal. By using such an olefin polymer (C), the shear strength of the adhesive can be increased. The polymerizable bond means an unsaturated carbon-carbon bond capable of polymerizing with the polymerizable monomer, and examples thereof include an unsaturated double bond, and preferably a (meth)acryloyl group. Examples of the olefin polymer (C) include polyolefins having a (meth)acryloyl group, such as polyolefins having a (meth)acryloyl group at only one terminal and polyolefins having a (meth)acryloyl group at both terminals. The polyolefin is a polymer of an aliphatic hydrocarbon compound having a double bond such as ethylene, propylene, butane, butadiene, isoprene, or a hydrogenated product thereof.

[0030] Examples of the polyolefin having a (meth)acryloyl group at only one terminal include polyethylene having a (meth)acryloyl group at one terminal, which is prepared by reacting polyethylene having an epoxy group at one terminal with (meth)acrylic acid. Also, polybutadiene having a (meth)acryloyl group at one terminal or a hydrogenated product thereof can be mentioned, and examples of its commercial products include "L-1253" manufactured by Kuraray Co., Ltd.

[0031] Examples of the olefin polymer having a (meth)acryloyl group at both terminals include polypropylene having a (meth)acryloyl group at both terminals, which is prepared by reacting polypropylene having an epoxy group at both terminals with (meth)acrylic acid. Also, polybutadiene having a (meth)acryloyl group at both terminals or a hydrogenated product thereof can be mentioned, and examples of its commercial products include "TEAI-1000", "EA-3000", "TE-2000" manufactured by Nippon Soda Co., Ltd., and "BAC-45" manufactured by Osaka Organic Chemical Industry Co., Ltd. The olefin polymer (C) may be used alone or in combination of two or more.

[0032] As the olefin polymer (C), among those described above, a polyolefin having a (meth)acryloyl group at both ends or one end is preferable, and among them, a polybutadiene having a (meth)acryloyl group at both ends or one end or a hydrogenated product thereof is preferable. In addition, when using a polyolefin having a (meth)acryloyl group at both ends as the olefin polymer (C), it becomes possible to polymerize the acrylic polymer in a network form. Therefore, it becomes easier to increase the cohesive force of the pressure-sensitive adhesive, and it becomes easier to adjust the adhesive properties of the pressure-sensitive adhesive layer. Furthermore, as the olefin polymer (C), it is preferable to use in combination an olefin polymer having a (meth)acryloyl group at one end and an olefin polymer having a (meth)acryloyl group at both ends.

[0033] The number average molecular weight of the olefin polymer (C) is preferably 500 to 20,000, more preferably 1,000 to 10,000. The number average molecular weight may be measured by gel permeation chromatography (GPC) and calculated using a calibration curve of standard polystyrene. In addition, the content of the structural unit derived from the olefin polymer (C) in the pressure-sensitive adhesive is preferably 1 to 20 parts by mass, more preferably 2 to 15 parts by mass, and even more preferably 4 to 12 parts by mass with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A).

[0034] [Other Monomers] The polymerizable monomer may contain other monomers other than the above (A) to (C). Examples of other monomers include styrene-based monomers and polyfunctional monomers. Examples of styrene-based monomers include styrene, α-methylstyrene, o-methylstyrene, and p-methylstyrene. In addition, examples of the polyfunctional monomer include monomers having two or more vinyl groups, and preferably polyfunctional (meth)acrylates having two or more (meth)acryloyl groups. When a polyfunctional monomer is used, it becomes possible to form a network structure in the acrylic polymer. Specific examples of the polyfunctional monomer include hexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, tris(2-hydroxyethyl)isocyanurate triacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, propoxylated glyceryl triacrylate, neopentyl glycol adipate diacrylate, and the like. When using other monomers, in the pressure-sensitive adhesive, the content of the structural unit derived from the other monomer is 0.5 to 15 parts by mass, more preferably 1 to 7 parts by mass, and still more preferably 1 to 5 parts by mass with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A).

[0035] [Adhesion-imparting resin] The acrylic pressure-sensitive adhesive may contain an adhesion-imparting resin from the viewpoint of improving the adhesive strength. As the adhesion-imparting resin, adhesion-imparting resins with low polymerization inhibition properties such as hydrogenated terpene resins, hydrogenated rosin, disproportionated rosin resins, and petroleum resins are preferred. Among these, since the adhesion-imparting resin having many double bonds inhibits the polymerization reaction, hydrogenated ones are preferred, and among them, hydrogenated petroleum resins are preferred. The softening point of the adhesion-imparting resin may be about 95°C or higher from the viewpoint of improving the cohesive force and adhesive strength of the pressure-sensitive adhesive, but preferably includes those of 120°C or higher. For example, those of 95°C or higher and less than 120°C and those of 120°C or higher and 150°C or lower may be used in combination. The softening point may be measured by the ring and ball method defined in JIS K2207. The content of the tackifier resin in the acrylic pressure-sensitive adhesive is preferably 5 to 40 parts by mass, more preferably 7 to 35 parts by mass, and still more preferably 10 to 25 parts by mass with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A).

[0036] [Other components] In addition to the components described above, the acrylic pressure-sensitive adhesive used in the present invention may contain various additives conventionally used in pressure-sensitive adhesives, such as fine particles other than metals having a lower potential than iron and other than the above conductive materials, plasticizers, softening agents, pigments, dyes, photopolymerization initiators, flame retardants, etc.

[0037] [Gel fraction] The gel fraction of the above acrylic pressure-sensitive adhesive is preferably 30 to 80% by mass. By setting the gel fraction within the above range, the cohesive force of the pressure-sensitive adhesive can be adjusted to an appropriate range, and it is easy to improve the pressure-sensitive adhesive properties such as adhesive strength. From these viewpoints, the gel fraction is preferably 40 to 70% by mass, and more preferably 45 to 65% by mass. The gel fraction can be adjusted to the above range by appropriately adjusting, for example, the olefin polymer (C) having two or more (meth)acryloyl groups, the presence or absence and the blending amount of the polyfunctional monomer. The gel fraction can be calculated from the following formula (1). The polymerizable monomer preferably contains at least one of a polyfunctional monomer and an olefin polymer (C) having two or more (meth)acryloyl groups in order to keep the gel fraction within the above range. Compounds having two or more functional groups such as polyfunctional monomers and olefin polymers (C) having two or more (meth)acryloyl groups are sometimes collectively referred to as crosslinking agents. Gel fraction (% by mass) = (B / A) × 100 Formula (1) A: Weight of the pressure-sensitive adhesive B: Dry weight of the insoluble matter of the pressure-sensitive adhesive after immersing the pressure-sensitive adhesive in tetrahydrofuran at 40 ° C for 48 hours

[0038] [Rubber-based pressure-sensitive adhesive] Next, a rubber-based pressure-sensitive adhesive used for the pressure-sensitive adhesive will be described. The rubber-based pressure-sensitive adhesive contains a rubber component and a tackifier resin. As the rubber component, it is preferable to use a styrene-isoprene block copolymer. The diblock ratio of the styrene-isoprene block copolymer is preferably 25 to 70% by mass, more preferably 30 to 65% by mass, and even more preferably 45 to 60% by weight. Here, the diblock refers to a diblock composed of styrene and isoprene. When the diblock ratio of the styrene-isoprene block copolymer is 25% or more, sufficient adhesive force is exhibited, and when it is 70% by mass or less, it is easy to increase the shear strength. In addition, the styrene-isoprene block copolymer contains, in addition to the diblock, those having three or more blocks such as a triblock composed of styrene, isoprene, and a styrene block.

[0039] The amount of styrene in the styrene-isoprene block copolymer is not particularly limited, but is preferably 14 to 24% by mass, more preferably 15 to 18% by mass. When the amount of styrene is 14% by mass or more, a pressure-sensitive adhesive with high cohesiveness is obtained. When it is 24% by mass or less, the cohesive force becomes appropriately large, and it is easy to exhibit appropriate pressure-sensitive adhesive performance. The molecular weight of the styrene-isoprene block copolymer is not particularly limited, but the mass average molecular weight is preferably 100,000 to 400,000, and more preferably 150,000 to 250,000. Here, the mass average molecular weight refers to the value measured as the polystyrene-equivalent molecular weight by the GPC (gel permeation chromatography) method.

[0040] As the tackifier resin used for the rubber-based pressure-sensitive adhesive, various tackifier resins can be used, but it is preferable to use petroleum resins, terpene resins, and coumarone resins. The tackifier resin may be used alone or in combination of two or more, but it is preferable to use a petroleum resin in combination with at least one selected from terpene resins and coumarone resins. Such a combination of tackifier resins easily improves the adhesive force. Examples of petroleum resins include aliphatic petroleum resins (C5 petroleum resins), alicyclic petroleum resins, aromatic petroleum resins, etc. From the perspective of compatibility with styrene-isoprene block copolymers, aliphatic petroleum resins are preferred. Also, it is preferable to use petroleum resins having a softening point of about 90 to 120°C. As for terpene resins, those having a softening point of about 80 to 120°C can be used, but those having a softening point of less than 100°C are preferred from the perspective of ensuring adhesiveness. Also, as for coumarone resins, in order to ensure cohesive force, those having a softening point preferably of 110 to 130°C, more preferably 115 to 125°C are used.

[0041] The tackifier resin is preferably 60 to 250 parts by mass, more preferably 100 to 200 parts by mass, and even more preferably 110 to 180 parts by mass with respect to 100 parts by mass of the rubber component. By setting the blending amount of the tackifier resin within the above range, the cohesive force can be improved and an appropriate tackiness can be imparted. Also, when using in combination a petroleum resin and at least one selected from terpene resins and coumarone resins, the petroleum resin is preferably 50 to 200 parts by mass, more preferably 60 to 150 parts by mass, and even more preferably 60 to 110 parts by mass with respect to 100 parts by mass of the rubber component. On the other hand, the terpene resin is preferably 10 to 70 parts by mass, more preferably 20 to 60 parts by mass, and even more preferably 30 to 50 parts by mass with respect to 100 parts by mass of the rubber component. Further, the coumarone resin is preferably 10 to 60 parts by mass, more preferably 15 to 50 parts by mass, and even more preferably 20 to 40 parts by mass with respect to 100 parts by mass of the rubber component. The rubber-based adhesive may contain the above-described fine particles in the same manner as the acrylic-based adhesive, and the rubber-based adhesive may also contain, if necessary, a softening agent, an antioxidant, a filler, etc.

[0042] <<Urethane-based adhesive>> The above-mentioned urethane adhesive is not particularly limited, and examples thereof include urethane resins obtained by reacting at least a polyol and a polyisocyanate compound. Examples of the above polyol include polyether polyol, polyester polyol, polycarbonate polyol, polycaprolactone polyol, and the like. Examples of the above polyisocyanate compound include diphenylmethane diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate, and the like. These urethane adhesives may be used alone or in combination of two or more. Further, as the urethane adhesive, a urethane resin obtained by reacting a polyurethane polyol and a polyfunctional isocyanate curing agent may be used. The polyurethane polyol may be one obtained by reacting the above-mentioned polyol and polyisocyanate compound, or one obtained by reacting a polyol, a polyisocyanate compound, and a chain extender such as diamine. The polyfunctional isocyanate curing agent may be a compound having two or more isocyanate groups, and the above-mentioned isocyanate compound can be used. In addition to the urethane resin, the urethane-based adhesive may contain the above-mentioned fine particles in the same manner as the acrylic-based adhesive. Further, the urethane-based adhesive may contain, if necessary, a tackifier resin, a softening agent, an antioxidant, a filler, and the like.

[0043] <<Silicone-based adhesive>> Examples of the silicone-based adhesive include addition reaction type, peroxide curing type, or condensation reaction type silicone-based adhesives. Among them, from the viewpoint of being curable at low temperature for a short time, the addition reaction type silicone-based adhesive is preferably used. The addition reaction type silicone-based adhesive cures during the formation of the adhesive layer. When using an addition reaction type silicone-based adhesive as the silicone-based adhesive, the silicone-based adhesive may contain a catalyst such as a platinum catalyst. Further, the silicone-based adhesive may contain the above-mentioned fine particles in the same manner as the acrylic-based adhesive, and various additives for adding a crosslinking agent and controlling the adhesive strength may also be added.

[0044] <Total light transmittance of the adhesive layer> The total light transmittance X per 1 μm thickness of the adhesive layer is preferably 99.85% or less. When the total light transmittance X is 99.85% or less, the corrosion protection property of the anticorrosive adhesive tape becomes good, and it becomes easier to prevent the corrosion of the adherend to which the anticorrosive adhesive tape is used. From the viewpoint of improving the corrosion protection property, the total light transmittance X is preferably 99.83% or less, more preferably 99.8% or less, and still more preferably 99.7% or less. Further, the total light transmittance X is preferably 97% or more, more preferably 98% or more, from the viewpoint of improving the curability of the entire adhesive layer when an acrylic adhesive is used. The total light transmittance X can be adjusted according to the type and content of the anisotropic conductive material and the like.

[0045] The total light transmittance X (%) per 1 μm thickness can be calculated based on the following formula from the total light transmittance Y (%) and the thickness T (μm) of the adhesive layer.

Equation

[0046] The total light transmittance Y is a value measured in accordance with JIS K7361-1. The total light transmittance can be measured using a haze meter (for example, Haze Meter NDH4000 manufactured by Nippon Denshoku Industries Co., Ltd.) at 23°C and in an atmosphere of 50% humidity.

[0047] <Resistance value of the adhesive layer> By containing the above-described anisotropic conductive material, the adhesive layer can efficiently transfer the electrons released when the metal in the metal layer is ionized to the adherend without making the resistance value too low. Specifically, the resistance value of the adhesive layer is, for example, 1×10 8 Ω or more, but preferably higher than 1×10 8 Ω. When the resistance value of the adhesive layer is 1×10 8When it is higher than Ω, the content of the anisotropic conductive material in the adhesive layer can be reduced, and the adhesiveness of the adhesive layer can be further improved. In addition, in the present invention, by using the anisotropic conductive material, even if the resistance value is high, electrons can be efficiently moved to the adherend, and sufficient corrosion protection can be ensured. Also, the resistance value of the adhesive layer is preferably 1×10 14 Ω or less. When the resistance value of the adhesive layer is 1×10 14 Ω or less, the electrons released when the metal in the metal layer is ionized can be sufficiently moved to the adherend, and the corrosion protection of the anti-corrosion adhesive tape can be improved. From such a viewpoint, the above resistance value is more preferably 1×10 9 ~5×10 13 Ω, and even more preferably 1×10 10 ~2×10 13 Ω or less. The resistance value of the adhesive layer can be measured by the method described in the examples below.

[0048] <Thickness of the adhesive layer> The thickness of the adhesive layer is preferably 20 μm or more. When the thickness of the adhesive layer is 20 μm or more, the adhesive layer can exhibit appropriate adhesiveness and corrosion protection. From such a viewpoint, the thickness of the adhesive layer is more preferably 50 μm or more, even more preferably 100 μm or more, even more preferably 150 μm or more, even more preferably 250 μm or more, and even more preferably 400 μm or more. The upper limit of the thickness of the adhesive layer is not particularly limited, but is, for example, 1 cm.

[0049] <Adhesiveness of the adhesive layer> The adhesiveness of the adhesive layer is preferably 10 N / 25 mm or more, more preferably 20 N / 25 mm or more, and even more preferably 30 N / 25 mm or more. The upper limit of the adhesiveness of the adhesive layer is not particularly limited, but is, for example, 110 N / 25 mm. The adhesiveness of the adhesive layer can be measured by the measurement method described in the examples below.

[0050] Further, the surface of the adhesive layer serving as the bonding surface may be protected by attaching a release sheet. As the release sheet, those obtained by subjecting at least one surface of a base material such as a resin film to a release treatment with a silicone-based release agent or the like are used.

[0051] <Base material> The anti-corrosion adhesive tape may have a base material in addition to the metal layer. The base material is preferably provided on the side opposite to the surface of the metal layer where the adhesive layer is provided. Further, the base material is preferably bonded to the metal layer via an adhesive layer made of an adhesive, a pressure-sensitive adhesive, or the like. Note that the adhesive layer is preferably an adhesive layer that does not contain a conductive material. With the above configuration, the adhesive layer containing the anisotropic conductive material is protected by the base material, and the anti-corrosion property of the anti-corrosion adhesive tape becomes more excellent. Examples of the base material include non-woven fabric, paper such as Japanese paper, woven fabric made of natural fiber, synthetic fiber, etc., resin film made of polyester, polyolefin, soft polyvinyl chloride, hard polyvinyl chloride, acetate, etc., and flat yarn cloth. In addition, as the adhesive and pressure-sensitive adhesive used for the adhesive layer, known ones may be appropriately used.

[0052] (Manufacturing method of anti-corrosion adhesive tape) The adhesive layer can be formed by applying an adhesive composition composed of components constituting the adhesive and a conductive material to the metal foil constituting the metal layer, and crosslinking, curing, etc. the adhesive composition as necessary. Further, the adhesive layer may be formed by applying the above adhesive composition to a release sheet and crosslinking, curing, etc. the adhesive composition as necessary. In this case, after forming the adhesive layer on the surface of the release sheet, a metal layer may be further formed on the surface of the adhesive layer. The formation of the metal layer may be performed, for example, by bonding a metal foil formed by thinly shaping a metal to the adhesive layer. Also, the metal layer may be formed by coating the surface of the adhesive layer with a metal by a thin film forming method such as sputtering or vacuum evaporation. The bonding of the metal foil and the coating of the metal on the adhesive layer may be performed after crosslinking and curing the adhesive composition, before crosslinking and curing, or while crosslinking and curing. Incidentally, the pressure-sensitive adhesive composition may be diluted with a solvent or the like as appropriate before use. Hereinafter, the case of using the above acrylic pressure-sensitive adhesive as the pressure-sensitive adhesive will be described in detail as an example.

[0053] When an acrylic pressure-sensitive adhesive is used for the pressure-sensitive adhesive layer, it can be obtained by irradiating light on a pressure-sensitive adhesive composition composed of a component constituting the pressure-sensitive adhesive containing the above polymerizable monomer and a conductive material to polymerize the polymerizable monomer. More specifically, first, a polymerizable monomer, an anisotropic conductive material, and, if necessary, a non-anisotropic conductive material, a tackifier resin, and other components are put into a reaction vessel such as a glass container and mixed to obtain a pressure-sensitive adhesive composition. Next, in order to remove dissolved oxygen in the pressure-sensitive adhesive composition, an inert gas such as nitrogen gas is generally supplied to purge the oxygen. Then, the pressure-sensitive adhesive composition is applied onto a release sheet or a metal layer. A protective release sheet may be further laminated on the applied pressure-sensitive adhesive composition. Thereafter, the pressure-sensitive adhesive layer is obtained by irradiating the pressure-sensitive adhesive composition with light such as ultraviolet light to polymerize the polymerizable monomer. In addition, for the pressure-sensitive adhesive layer formed on the release sheet, after appropriately peeling off the protective release sheet, a metal layer may be further formed on the surface opposite to the surface provided with the release sheet, so that a metal layer is provided on the surface of the pressure-sensitive adhesive layer. In addition, in the obtained food-proof pressure-sensitive adhesive tape, a base material may be further attached onto the metal layer using an adhesive or a pressure-sensitive adhesive.

[0054] The steps from the application or impregnation of the pressure-sensitive adhesive composition to the irradiation with light are preferably carried out in an inert gas atmosphere or in a state where oxygen is blocked by a film or the like. Incidentally, in this manufacturing method, the pressure-sensitive adhesive composition obtained by mixing each component may be pre-polymerized before being applied to a release sheet or a metal layer or the like in order to increase the viscosity.

[0055] Examples of lamps that can be used when irradiating the adhesive composition with light include, for example, low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, chemical lamps, black light lamps, microwave-excited mercury lamps, and metal halide lamps. Among these, chemical lamps are preferred. The light irradiation intensity when irradiating the adhesive composition with light varies depending on the presence or absence of a photoinitiator, etc., but is preferably about 0.1 to 100 mW / cm 2 is preferred.

[0056] (Configuration example of anti-edible adhesive tape) Figs. 1 to 4 show configuration examples of the anti-edible adhesive tape of the present invention. In the anti-edible adhesive tape 10 shown in Fig. 1, an adhesive layer 11 containing an anisotropic conductive material 13 is provided on one surface 15A of a metal layer 15 made of a metal having a lower potential than iron. The adhesive layer 11 has a surface 11A on the side opposite to the side where the metal layer 15 is provided bonded to the adherend.

[0057] In the anti-edible adhesive tape 10 shown in Fig. 2, an adhesive layer 11 containing an anisotropic conductive material 13 is provided on one surface 15A of a metal layer 15 of a metal foil made of a metal having a lower potential than iron. Further, an adhesive layer 16 not containing a conductive material is provided on the surface 15B of the metal layer 15 where the adhesive layer 11 is not provided. Also, a base material 14 is provided on the surface 16A of the adhesive layer 16 where the metal layer 15 is not provided. The details of the base material 14 are as described above. With such a configuration, the adhesive layer 11 is protected by the base material 14, and the anti-corrosion property of the anti-edible adhesive tape becomes more excellent.

[0058] In the anti-edible adhesive tape 10 shown in Fig. 3, an adhesive layer 11 containing an anisotropic conductive material 13 and a non-anisotropic conductive material 12 is provided on one surface 15A of a metal layer 15 made of a metal having a lower potential than iron. Thereby, the content of the conductive materials 12 and 13 in the adhesive layer 11 can be increased, and the anti-corrosion property of the anti-edible adhesive tape 10 can be further improved.

[0059] In the anti-edible adhesive tape 10 shown in Fig. 4, an adhesive layer 11 containing an anisotropic conductive material 13 and an isotropic conductive material 12 is provided on one surface 15A of a metal layer 15 made of a metal having a lower potential than iron. Further, an adhesive layer 16 not containing a conductive material is provided on a surface 15B of the metal layer 15 where the adhesive layer 11 is not provided. Further, a base material 14 other than a metal foil made of a metal having a lower potential than iron is provided on a surface 16A of the adhesive layer 16 where the metal layer 15 is not provided.

Example

[0060] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[0061] <Evaluation method> In the examples and comparative examples, the anti-edible adhesive tape was evaluated by the following evaluation methods. (Total light transmittance) The total light transmittance Y of the adhesive layer was measured in accordance with JIS K7361-1. Specifically, the total light transmittance Y was measured using a haze meter (for example, Haze Meter NDH4000 manufactured by Nippon Denshoku Industries Co., Ltd.) at 23°C and a humidity of 50%. The total light transmittance X per 1 μm thickness was calculated based on the following formula from the total light transmittance Y and the thickness T (μm) of the adhesive layer.

Equation

[0062] (Resistance value) After peeling off the release sheet from the 50 mm × 50 mm anti-edible adhesive tapes obtained in each example and comparative example, the resistance value was measured as follows according to the resistance value. For high-resistance (resistance value 10 4 Ω or more) anti-edible adhesive tapes, an electrode URS probe (manufactured by Mitsubishi Chemical Analytech Co., Ltd.) was attached to a resistivity meter Hiresta-UP MCP-HT450 (manufactured by Mitsubishi Chemical Analytech Co., Ltd.), and the resistance value was measured by bringing the electrode into contact with the surface of the anti-edible adhesive tape. For low-resistance (resistance value 10 4The anti - edible adhesion tape with a resistance less than

[0063] (Sacrificial corrosion resistance evaluation) On a steel plate SS400 (manufactured by TP Giken Co., Ltd., 150 mm × 70 mm) as the adherend, the 150 mm × 70 mm anti - edible adhesion tapes obtained in each example and comparative example were pasted after peeling off the release sheet. Then, a part (3 mm × 3 mm) of the anti - edible adhesion tape was cut out, a 3 mass% NaCl aqueous solution was dripped thereon, and using a silver / silver chloride electrode, the electrode tip was arranged to touch the NaCl aqueous solution, and the potential was measured. In the measurement of the potential, as a tester, a digital multimeter "CDM - 11D" (manufactured by Custom Co., Ltd.) was used, and its negative electrode and an electrode "HS - 205C" (manufactured by Toa DKK Corporation) were connected with an electrode clip and used. Based on the measured potential, the sacrificial corrosion resistance was evaluated according to the following evaluation criteria. A: The potential was - 700 mV or less, and the sacrificial corrosion resistance was good. B: The potential was greater than - 700 mV, and the sacrificial corrosion resistance was insufficient.

[0064] (Adhesion evaluation) The adhesion of the adhesive layers prepared in each example and comparative example was carried out as follows. After cutting the anti - edible adhesion tape obtained in each example to a length of 100 mm × 25 mm, it was bonded to a SUS plate through the adhesive layer to obtain a measurement sample. The bonding to the SUS plate was performed by reciprocating a 2 kg roller at a speed of 10 ± 0.5 mm / s for a total of 2 reciprocations. The measurement sample was fixed to the chuck of a tensile testing machine ("Tensilon universal material testing machine" manufactured by A&D Company, Ltd.). Then, the anti - edible adhesion tape was pulled at a peeling angle of 180° and a speed of 300 mm / min for 60 mm or more in an environment of 23°C and 50% RH, and the interval average value of the load (N) detected by the load cell was recorded, and this was taken as the adhesion (N / 25 mm). A: The adhesive force was 30 N / 25 mm or more, and the adhesiveness was quite good. B: The adhesive force was 10 N·25 mm or more and less than 30 N / 25 mm, and the adhesiveness was good. C: The adhesive force was less than 10 N / 25 mm, and the adhesiveness was insufficient.

[0065] [Examples 1 to 4 and Comparative Examples 1 to 3] An adhesive having the formulation described in Table 1 was prepared, and an anisotropic conductive material or a non-anisotropic conductive material was blended into the adhesive so as to have the content ratio described in Table 2 to obtain an adhesive composition. Nitrogen was purged into this adhesive composition to remove dissolved oxygen. Next, a spacer having the same thickness as the target thickness was placed on the release-treated surface of the release sheet, and the adhesive composition was applied onto the release-treated surface of the release sheet. Next, another release sheet was covered on the applied adhesive composition such that the release-treated surface was in contact with the adhesive composition. Note that, as the release sheet, a PET film (thickness: 50 μm) subjected to a silicone release treatment was used. In this state, the lamp intensity of the chemical lamp was adjusted so that the ultraviolet irradiation intensity on the release sheet on the covering side became 5 mW / cm 2 and ultraviolet rays were irradiated for 15 minutes to obtain an adhesive layer with release sheets attached to both sides. The gel fraction was 55%. A metal layer (zinc foil, thickness: 50 μm) was attached to one surface of this adhesive layer to produce an anti-corrosion adhesive tape. The resistance value, sacrificial corrosion protection property, and adhesive force of the obtained anti-corrosion adhesive tape were evaluated. The evaluation results are shown in Table 2.

[0066]

Table 1

[0067] ※ Each component in Table 1 is as follows. Olefin polymer: Trade name "L-1253", manufactured by Kuraray Co., Ltd., hydrogenated polybutadiene having a (meth)acryloyl group at one end Adhesion-imparting resin 1: Trade name "Alcon P140", manufactured by Arakawa Chemical Industries, Ltd., hydrogenated petroleum resin, softening point 140°C Adhesive resin 2: Trade name "Alcon P100", manufactured by Arakawa Chemical Industries, Ltd., hydrogenated petroleum resin, softening point 100 °C Fine particles: Trade name "Celstar Z-27", manufactured by Tokai Kogyo Co., Ltd., glass balloon Crosslinking agent: Trade name "TEAI-1000", manufactured by Nippon Soda Co., Ltd. Polymerization initiator: 2,2-dimethoxy-2-phenylacetophenone

[0068]

Table 2

[0069] Each component in Table 2 is as follows. Anisotropic conductive material: Carbon nanotube (CNT), manufactured by JEIO Co., Ltd., trade name "JENOTUBE8A", average diameter 6 - 9 nm, average length 100 - 200 μm Isotropic conductive material: Carbon black, manufactured by Orient Industry Co., Ltd., trade name "AT-NO.15S"

[0070] As is clear from the results of Examples 1 to 4 above, when the metal layer is a metal foil of a metal with a lower potential than iron and the adhesive layer contains an anisotropic conductive material, it was found that excellent corrosion resistance and good adhesiveness of the anticorrosive adhesive tape can be achieved simultaneously. On the other hand, as is clear from the results of Comparative Examples 1 to 3, even when the metal layer is a metal foil of a metal with a lower potential than iron, if the adhesive layer does not contain an anisotropic conductive material, it was found that excellent corrosion resistance and good adhesiveness of the anticorrosive adhesive tape cannot be achieved simultaneously.

Explanation of symbols

[0071] 10 Anticorrosive adhesive tape 11 Adhesive layer 12 Isotropic conductive material 13 Anisotropic conductive material 14 Base material 15 Metal layer 16 Adhesive layer

Claims

1. A metal layer and an adhesive layer provided on at least one surface of the metal layer, wherein the metal layer is a layer of a metal having a lower potential than iron, the adhesive layer contains an anisotropic conductive material, the adhesive used for the adhesive layer is at least one adhesive selected from the group consisting of an acrylic adhesive, a rubber adhesive, a urethane adhesive, and a silicone adhesive, An anti-edible adhesive tape, wherein the content of the anisotropic conductive material in the adhesive layer is 0.008 to 0.5 parts by mass with respect to 100 parts by mass of the adhesive.

2. The adhesive tape according to Claim 1, wherein the total light transmittance X per 1 μm thickness of the adhesive layer is 99.85% or less.

3. The anti-edible adhesive tape according to Claim 1 or 2, wherein the aspect ratio of the anisotropic conductive material is 2 or more.

4. The anti-edible adhesive tape according to any one of Claims 1 to 3, wherein the anisotropic conductive material is a carbon-based material.

5. The anti-edible adhesive tape according to Claim 4, wherein the carbon-based material is a carbon nanotube.

6. The resistance value of the adhesive layer is 1 × 10 ８ to 1 × 10 １４ Ω, and the anti-edible adhesive tape according to any one of claims 1 to 5.

7. The anti-edible adhesive tape according to any one of Claims 1 to 6, wherein the thickness of the adhesive layer is 20 μm or more.

8. The anti-edible adhesive tape according to any one of Claims 1 to 7, wherein the metal layer is a zinc foil.

9. The anti-edible adhesive tape according to any one of Claims 1 to 8, wherein the thickness of the metal layer is 2.5 μm or more.

Images