JP2022136776A - Anticorrosive adhesive tape and anticorrosive method for steel structures - Google Patents

Abstract

To provide an anticorrosive material that has excellent work efficiency but yet exerts excellent anticorrosive effect even when disposed between two structures, and an anticorrosive method for steel structures using the anticorrosive material.SOLUTION: An anticorrosive adhesive tape 10 is disposed between a first structure 20 and a second structure 30. The first structure 20 is a steel structure and the anticorrosive adhesive tape 10 has an adhesive layer 11. An anticorrosive method for steel structures has the steps for: bonding the anticorrosive adhesive tape 10 to the first structure 20; and placing at least one of the first and second structures 20, 30 so that the anticorrosive adhesive tape is disposed between the first and second structures 20, 30.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to an anticorrosion adhesive tape and a corrosion prevention method for steel structures using the anticorrosion adhesive tape.

Anticorrosive paint compositions containing zinc are widely used to prevent corrosion of steel structures (see, for example, Patent Document 1). By applying the anticorrosive coating composition described in Patent Document 1 to a steel structure, the steel structure can be shielded from substances that affect corrosion, such as oxygen, water, and corrosive substances. Furthermore, since zinc is a metal with a lower potential than iron and has a sacrificial anti-corrosion effect, the anti-corrosion coating composition described in Patent Document 1 has high anti-corrosion properties.

JP 2020-143273 A

However, anticorrosion with a coating composition requires a drying process after application, and the work takes time. For example, when performing local repairs in civil engineering and construction applications such as bridges, work efficiency decreases. . Further, if another member is placed on the paint without drying time in order to shorten the working time, the paint film cannot be properly formed and the anti-corrosion property cannot be sufficiently secured.
Therefore, the present invention aims to provide an anticorrosion material that is excellent in work efficiency and has good anticorrosion properties even when placed between two structures, and a method for preventing corrosion of a steel structure using the anticorrosion material. Make it an issue.

As a result of intensive studies, the present inventors found that an adhesive tape is an anticorrosion material that is excellent in work efficiency and has good anticorrosion properties even when placed between two structures. completed.
That is, the present invention provides the following [1] to [12].
[1] An anti-corrosion pressure-sensitive adhesive tape which is disposed between a first structure and a second structure, the first structure being a steel structure, and comprising an adhesive layer.
[2] The second structure is a concrete structure, a mortar structure, a steel structure, a metal structure other than steel, a thermoplastic resin structure, a thermosetting resin structure, and a fiber-reinforced plastic structure. The anticorrosive pressure-sensitive adhesive tape according to [1] above, which is at least one structure selected from the group consisting of:
[3] The anticorrosion pressure-sensitive adhesive tape according to the above [1] or [2], which consists only of the pressure-sensitive adhesive layer.
[4] The anticorrosion pressure-sensitive adhesive tape according to any one of [1] to [3] above, wherein the pressure-sensitive adhesive layer contains a metal having a potential lower than that of iron.
[5] The anti-corrosion pressure-sensitive adhesive tape according to any one of [1] to [4] above, further comprising a base material, wherein the pressure-sensitive adhesive layer is provided on one side of the base material.
[6] The anticorrosion pressure-sensitive adhesive tape according to [5] above, wherein the substrate is at least one sheet-like material selected from the group consisting of resin films, nonwoven fabrics, and metal foils.
[7] further comprising a metal layer, wherein the pressure-sensitive adhesive layer is provided on one side of the metal layer;
The anticorrosion pressure-sensitive adhesive tape according to the above [1] or [2], wherein the metal layer is a layer of a metal having a potential less noble than that of iron.
[8] The anticorrosion pressure-sensitive adhesive tape according to the above [4] or [7], wherein the metal having a potential lower than that of iron is zinc.
[9] The anticorrosion adhesive according to any one of the above [4], [7], and [8], wherein the adhesive layer contains a conductive material other than a metal having a potential lower than that of iron. tape.
[10] The anticorrosive pressure-sensitive adhesive tape according to [9] above, wherein the conductive material is a carbon nanotube.
[11] The anticorrosion pressure-sensitive adhesive tape according to any one of [1] to [10] above, wherein the pressure-sensitive adhesive layer has a storage elastic modulus G' of 50,000 to 1,000,000 Pa at 23°C.
[12] A step of attaching the anticorrosion adhesive tape according to any one of [1] to [11] above to the first structure, and the anticorrosion adhesive tape between the first and second structures A method of preventing corrosion of a steel structure, comprising the step of placing at least one of said first and second structures such that an adhesive tape is positioned thereon.

ADVANTAGE OF THE INVENTION According to the present invention, it is possible to provide an anti-corrosion material that is excellent in work efficiency and has good anti-corrosion properties even when placed between two structures, and a method for preventing corrosion of a steel structure using the anti-corrosion material. can.

FIG. 1 is a schematic diagram showing an example of use of the anticorrosion pressure-sensitive adhesive tape of one embodiment of the present invention. FIG. 2 is a schematic diagram showing a usage example of a modification of the anticorrosion pressure-sensitive adhesive tape of one embodiment of the present invention. FIG. 3 is a schematic diagram showing a usage example of a modification of the anticorrosion pressure-sensitive adhesive tape of one embodiment of the present invention. FIG. 4 is a schematic diagram showing a usage example of a modification of the anticorrosion pressure-sensitive adhesive tape of one embodiment of the present invention.

[Anti-corrosion adhesive tape]
An anticorrosive pressure-sensitive adhesive tape according to one embodiment of the present invention will be described with reference to FIG. The anticorrosion pressure-sensitive adhesive tape 10 of one embodiment of the present invention is placed between a first structure 20 and a second structure 30 and used. The first structure 20 is a steel structure, and the anticorrosion adhesive tape 10 has an adhesive layer 11 . Since the anti-corrosion adhesive tape 10 of one embodiment of the present invention is an adhesive tape, simply by attaching it to the first structure 20, substances such as oxygen, water, and corrosive substances that affect corrosion are removed from the first structure. structure 20 can be blocked. Therefore, no coating and drying are required to form a layer for insulating the first structure 20 from substances such as oxygen, water, corrosives, and the like. Since the second structure 30 can be placed adjacent to the first structure 20 without drying time, the anticorrosive adhesive tape 10 of one embodiment of the present invention has excellent work efficiency. Although it is simple, it can exhibit good anti-corrosion properties even when placed between two structures.
Steel structures include, for example, bridges, steel towers, viaducts, tanks, plants, bridge piers, and the like. Moreover, the metal material constituting the steel structure is, for example, a metal material containing at least one selected from the group consisting of iron and alloys containing iron. Specific examples of alloys containing iron include nickel-chromium steel, nickel-chromium-molybdenum steel, chromium steel, chromium-molybdenum steel, manganese steel, and other alloy steels, and various steel materials, such as carbon steel.

The second structure 30 is not particularly limited as long as it is a structure used in combination with a steel structure. The second structure 30 includes, for example, a concrete structure, a mortar structure, a steel structure, a metal structure other than steel, a thermoplastic resin structure, a thermosetting resin structure, a fiber-reinforced plastic structure, and the like. is mentioned. These structures can be used individually by 1 type or in combination of 2 or more types. For example, in a steel highway bridge, the H steel of the floor framing is the first structure, and the concrete floor slab placed on the floor framing members is the second structure.

<Metal with a more base potential than iron>
The pressure-sensitive adhesive layer 11 preferably contains a metal having a lower potential than iron. By containing a metal whose potential is less noble than that of iron (hereinafter also referred to as a "sacrificial anti-corrosion metal"), the first structure 20 has sacrificial anti-corrosion properties, and the anti-corrosion properties of the first structure 20 are enhanced. The sacrificial anti-corrosion metal is dispersed in the adhesive constituting the adhesive layer 11 .

Examples of sacrificial anticorrosion metals include cadmium, chromium, zinc, manganese, and aluminum. Among these, zinc and aluminum are preferred, and zinc is particularly preferred. By using zinc, sacrificial corrosion resistance becomes excellent.

The sacrificial anti-corrosion metal may be dispersed in the pressure-sensitive adhesive in any form as a filler such as particles, scales, or spindles, but is preferably in the form of particles. The sacrificial anti-corrosion metal is in the form of particles, so that it can be easily dispersed in the pressure-sensitive adhesive layer 11 without substantially reducing the adhesiveness of the pressure-sensitive adhesive layer 11 .
In the present specification, the particle shape means that the ratio of the length in the long axis direction to the length in the short axis direction (aspect ratio) is small, for example, the aspect ratio is 3 or less, preferably 2 or less. The shape of the particles is not particularly limited, but may be spherical or amorphous such as powder. The particle size of the metal is, for example, 1 to 500 μm, preferably 1 to 200 μm. In addition, in this specification, the particle size means the average particle size measured by the laser diffraction method.

The content of the sacrificial anti-corrosion metal in the adhesive layer 11 is, for example, 1 to 30% by mass, preferably 3 to 25% by mass, more preferably 7 to 20% by mass, based on the total amount of the adhesive layer 11. is.
When the content of the sacrificial anti-corrosion metal is at least these lower limits, the anti-corrosion performance increases, and when it is at most these upper limits, the adhesive strength increases.

<Conductive material>
The pressure-sensitive adhesive layer 11 preferably further contains a conductive material other than the sacrificial anticorrosion metal, in addition to the sacrificial anticorrosion metal.
Examples of conductive materials include one or more selected from carbon-based materials, metal-based materials, metal oxide-based materials, ionic polymers, and conductive polymers.
Carbon-based materials include carbon black, graphite, graphene, carbon nanotubes, acetylene black, and the like. Examples of metal-based materials include metals whose potential is nobler than that of iron, such as gold, silver, copper, nickel, or alloys containing these, or iron. Examples of metal oxide materials include indium tin oxide (ITO), antimony trioxide (ATO), fluorine-doped tin oxide (FTO), and zinc oxide. Examples of conductive polymers include polyacetylene, polypyrrole, PEDOT (polyethylenedioxythiophene), PEDOT/PSS (composite of polyethylenedioxythiophene and polystyrenesulfonic acid), polythiophene, polyaniline, poly(p-phenylene), polyfluorene, Examples include polycarbazole, polysilane, and derivatives thereof. Examples of ionic polymers include sodium polyacrylate and potassium polyacrylate.
These conductive materials may be used singly, or two or more of them may be used in combination.
Among the above materials, the conductive material is preferably a carbon-based material, and more preferably a carbon nanotube.

<Carbon nanotube>
The adhesive layer 11 preferably contains carbon nanotubes. By containing carbon nanotubes, the sacrificial anti-corrosion property of the adhesive layer 11 can be improved and the adhesive force can be maintained high, so that the anti-corrosion adhesive tape 10 having both high adhesive force and sacrificial anti-corrosive property can be easily obtained. This is because carbon nanotubes are a conductive material, but compared to other types of conductive materials, the amount required to develop a certain degree of sacrificial corrosion resistance is small, so the degree of decrease in adhesive strength is small. guessed.

Carbon nanotubes are tubular materials formed from carbon. Carbon nanotubes have excellent electrical properties, and when compounded with resin or the like, they can form highly conductive sheets and the like. A carbon nanotube is a substance that has a structure in which a graphite sheet with a hexagonal mesh-like carbon atom arrangement is rolled into a cylinder. .
In the anticorrosive pressure-sensitive adhesive tape 10 of one embodiment of the present invention, the type of carbon nanotube is not particularly limited, and may be single-wall carbon nanotube, multi-wall carbon nanotube, or a mixture containing these in an arbitrary ratio. Also, carbon nanotubes manufactured by various methods such as an arc discharge method, a laser evaporation method, a chemical vapor deposition method (CVD method), and the like can be used.

The average diameter of the carbon nanotubes is preferably 1-100 nm, more preferably 2-15 nm. The average length of the carbon nanotubes is preferably 0.1-1000 μm, more preferably 10-500 μm. The aspect ratio (average length/average diameter) of the carbon nanotubes is preferably 10-100,000, more preferably 500-30,000.
The diameter of the carbon nanotube indicates the outer diameter in the case of a single-wall carbon nanotube, and means the outer diameter of the outermost tube in the case of a multi-wall carbon nanotube. The diameter and length of carbon nanotubes may be measured, for example, in an image obtained by observation with a TEM (transmission electron microscope), and the average diameter and average length are determined by the arithmetic average of 50 arbitrary numbers. good.

From the viewpoint of sacrificial corrosion resistance and adhesive strength of the adhesive layer 11, the content of the conductive material in the adhesive layer 11 is preferably 0.005 to 30% by mass, more preferably 0%, based on the total amount of the adhesive layer 11. 0.005 to 20 mass %, more preferably 0.006 to 10 mass %. In addition, when using a material other than carbon nanotubes as the conductive material, it is preferable to contain a relatively large amount of the conductive material from the viewpoint of sacrificial corrosion resistance. is preferably 0.5 to 30% by mass, more preferably 1 to 20% by mass, still more preferably 2 to 10% by mass.

When the conductive material is carbon nanotubes, the content of the carbon nanotubes in the adhesive layer 11 is preferably 0.0005 to 0.7% by mass, more preferably 0.005% by mass, based on the total amount of the adhesive layer 11 . 005 to 0.05% by mass, more preferably 0.006 to 0.045% by mass.
When the content of carbon nanotubes is at least these lower limits, the sacrificial corrosion resistance tends to be enhanced, and when the content of carbon nanotubes is at most these upper limits, adhesive strength tends to be improved.

<Adhesive>
The adhesive layer 11 is preferably made of an adhesive. Although the type of adhesive is not particularly limited, acrylic adhesives, rubber-based adhesives, urethane-based adhesives, silicone-based adhesives, and the like can be used. These may be used alone or in combination.
Among these, the adhesive layer 11 is preferably formed of an acrylic adhesive.

(Acrylic adhesive)
An embodiment of the acrylic pressure-sensitive adhesive used for the pressure-sensitive adhesive layer 11 will be described in more detail below. The acrylic pressure-sensitive adhesive is a pressure-sensitive adhesive containing an acrylic polymer obtained by polymerizing a polymerizable monomer containing a (meth)acrylic acid alkyl ester-based monomer (A).
In this specification, the term "(meth)acrylic acid alkyl ester" refers to a concept including both acrylic acid alkyl ester and methacrylic acid alkyl ester, and the same applies to other similar terms. . In addition, the term "polymerizable monomer" includes not only compounds having no repeating unit, but also compounds that copolymerize with the (meth)acrylic acid alkyl ester monomer (A), such as the olefin polymer (C) described later. refers to the concept that the monomer itself may include those having repeating units.

((Meth)acrylic acid alkyl ester-based monomer (A))
(Meth)acrylic acid alkyl ester-based monomer (A) is an ester of (meth)acrylic acid and an aliphatic alcohol, and the number of carbon atoms in the alkyl group of the aliphatic alcohol is preferably 2 to 14, more preferably Alkyl esters derived from fatty alcohols that are 4-10 are preferred. When the number of carbon atoms in the alkyl group is within this range, it becomes easier to adjust the storage elastic modulus at 23° C. and the adhesive strength of the pressure-sensitive adhesive within the ranges described above.

Specific (meth)acrylic acid alkyl ester-based monomers (A) include, 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 Acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate and the like.
Among these, n-butyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate and n-octyl (meth)acrylate are preferred, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate or combinations thereof are more preferred.
The (meth)acrylic acid alkyl ester-based monomers may be used alone, or two or more of them may be used in combination.

The (meth)acrylic acid alkyl ester-based monomer (A)-derived structural unit constitutes the main component in the adhesive layer, and its content is generally 30% by mass or more based on the total amount of the adhesive layer. , preferably 50% by mass or more, more preferably 70% by mass or more. Thus, when the content of the (meth)acrylic acid alkyl ester monomer (A) is increased, it becomes possible to impart desired adhesive strength to the adhesive layer. In addition, the content of the structural unit derived from the (meth)acrylic acid alkyl ester-based monomer (A) is, for example, 97% by mass or less, preferably 95% by mass or less, or more, in order to contain a certain amount or more of other components. Preferably, it is 90% by mass or less.
The content of the structural unit derived from the (meth)acrylic acid alkyl ester-based monomer (A) in the pressure-sensitive adhesive layer is the same as the content of the (meth)acrylic acid alkyl ester-based monomer (A) in the pressure-sensitive adhesive composition described later. Since they are substantially the same, they can be expressed interchangeably. The same applies to components other than the (A) component, such as the (B) and (C) components described below.

(Polar group-containing vinyl monomer (B))
The polymerizable monomer preferably contains a polar group-containing vinyl monomer (B) in addition to the (meth)acrylic acid alkyl ester monomer (A). The polar group-containing vinyl monomer (B) has a polar group and a vinyl group. By using the polar group-containing monomer (B), it becomes easier to improve the adhesive strength to the adherend.
Examples of the polar group-containing vinyl monomer (B) include carboxylic acid vinyl esters such as vinyl acetate, (meth)acrylic acid, carboxylic acids containing a vinyl group such as itaconic acid, and their anhydrides, 2-hydroxyethyl (Meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, caprolactone-modified (meth) acrylate, polyoxyethylene (meth) acrylate, and polyoxypropylene (meth) acrylate hydroxyl groups such as vinyl monomers having, (meth)acrylonitrile, N-vinylpyrrolidone, N-vinylcaprolactam, N-vinyllauryllactam, (meth)acryloylmorpholine, (meth)acrylamide, dimethyl (meth)acrylamide, N-methylol (meth)acrylamide , N-butoxymethyl (meth)acrylamide, and dimethylaminomethyl (meth)acrylate.
Among these, (meth)acrylic acid, carboxylic acids containing a vinyl group such as 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.

When the polar group-containing vinyl monomer (B) is used, the content of the structural unit derived from the polar group-containing vinyl monomer (B) in the pressure-sensitive adhesive layer 11 is equal to that of the (meth)acrylic acid alkyl ester-based monomer (A)-derived constitutional unit. It is preferably 1 to 15 parts by mass, more preferably 2 to 12 parts by mass, and still more preferably 3 to 10 parts by mass with respect to 100 parts by mass. By setting the content of the polar group-containing vinyl monomer (B) within such a range, it becomes easier to improve the adhesive strength to the first structure 20 .

(Olefin polymer (C))
The polymerizable monomer preferably further contains an olefin polymer (C) having a polymerizable bond at one end. By using such an olefin polymer (C), it becomes easier to improve the adhesive strength to the first structure 20 .
The polymerizable bond means an unsaturated carbon-carbon bond capable of polymerizing with a polymerizable monomer, and includes, for example, an unsaturated double bond, preferably a (meth)acryloyl group.
Examples of the olefin polymer (C) include polyolefins having a (meth)acryloyl group at one end. Polyolefins are polymers of aliphatic hydrocarbon compounds having double bonds such as ethylene, propylene, butane, butadiene and isoprene, or hydrogenated products thereof.

As the polyolefin having a (meth)acryloyl group at one end, for example, a polyolefin having a (meth)acryloyl group at one end prepared by reacting polyethylene having an epoxy group at one end with (meth)acrylic acid Polyethylene etc. are mentioned. In addition, polybutadiene having a (meth)acryloyl group at one end or a hydrogenated product thereof may be mentioned, and commercially available products thereof include "L-1253" manufactured by Kuraray Co., Ltd. and the like.

The olefin polymer (C) preferably has a number average molecular weight of 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 standard polystyrene calibration curve.
In addition, the content of the structural unit derived from the olefin polymer (C) in the adhesive layer 11 is 1 to 20 parts by mass with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A). is preferred, 2 to 15 parts by weight is more preferred, and 4 to 12 parts by weight is even more preferred.

(Crosslinking agent (D))
Preferably, the polymerizable monomer further contains a cross-linking agent. Examples of the cross-linking agent include polyfunctional monomers having two or more vinyl groups, preferably polyfunctional (meth)acrylates having two or more (meth)acryloyl groups. Using a polyfunctional monomer makes it easier to adjust the adhesive strength of the adhesive layer to an appropriate range.
Polyfunctional (meth)acrylates are not particularly limited, and hexanediol di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, tris(2-hydroxyethyl)isocyanurate triacrylate, ethoxylated trimethylolpropane triacrylate, Polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, liquid hydrogenated 1,2- Examples include polymers such as polybutadiene di(meth)acrylate. Among these polyfunctional (meth)acrylates, polymers are preferred, and liquid hydrogenated 1,2-polybutadiene diacrylate is more preferred. Commercial products of liquid hydrogenated 1,2-polybutadiene diacrylate include “TEAI-1000” manufactured by Nippon Soda Co., Ltd., and the like.
In addition, the content of the structural unit derived from the crosslinking agent in the adhesive layer 11 is preferably 0.1 to 4 parts by mass with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A). , more preferably 0.3 to 3 parts by mass, more preferably 0.5 to 2 parts by mass.

(tackifying resin)
The acrylic pressure-sensitive adhesive may contain a tackifying resin from the viewpoint of improving adhesive strength. As the tackifying resin, a tackifying resin with low polymerization inhibition such as hydrogenated terpene resin, hydrogenated rosin, disproportionated rosin resin, petroleum resin, etc. is preferable. Among these, hydrogenated resins are preferred, and among them, hydrogenated petroleum resins are preferred because polymerization reaction is inhibited when the tackifier resin has a large number of double bonds.
The softening point of the tackifier resin may be about 95°C or higher from the viewpoint of improving the cohesive strength and adhesive strength of the adhesive, but preferably includes 120°C or higher, such as 95°C or higher and 120°C. A temperature of less than 120° C. or more and a temperature of 120° C. or more and 150° C. or less may be used together. The softening point may be measured by the ring and ball method defined in JIS K2207.
The content of the tackifying resin in the acrylic pressure-sensitive adhesive is preferably 5 to 40 parts by mass, more preferably 7 to 35 parts by mass, with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A). parts by mass, more preferably 10 to 25 parts by mass.

(fine particles)
The acrylic pressure-sensitive adhesive may contain fine particles. Adhesion can be improved by containing fine particles.
Examples of fine particles include inorganic hollow particles such as glass balloons, shirasu balloons, and fly ash balloons, organic hollow particles made of polymethyl methacrylate, acrylonitrile-vinylidene chloride copolymer, polystyrene, phenolic resin, etc., glass beads, and silica beads. , inorganic fine particles such as synthetic mica, and organic fine particles such as polyethyl acrylate, polyurethane, polyethylene, and polypropylene.
The content of the fine particles in the acrylic pressure-sensitive adhesive is preferably 0.1 to 15 parts by mass, more preferably 0.5 parts by mass, with respect to 100 parts by mass of the structural unit derived from the (meth)acrylic acid alkyl ester monomer (A). to 10 parts by mass, more preferably 0.7 to 5 parts by mass.

(other ingredients)
The acrylic pressure-sensitive adhesive used for the pressure-sensitive adhesive layer 11 includes, in addition to the components described above, various additives conventionally used in pressure-sensitive adhesives, such as plasticizers, softeners, pigments, dyes, photopolymerization initiators, and flame retardants. may contain.

(Method for producing acrylic pressure-sensitive adhesive and pressure-sensitive adhesive layer)
The acrylic pressure-sensitive adhesive can be obtained by irradiating the pressure-sensitive adhesive composition containing the polymerizable monomer, the sacrificial anticorrosion metal, and the carbon nanotubes with light to polymerize the polymerizable monomer. In addition, the pressure-sensitive adhesive composition may contain at least one of the above-described tackifying resin, fine particles, and other components, if necessary.
More specifically, first, a polymerizable monomer, a sacrificial anticorrosive metal, carbon nanotubes, and optionally a tackifying resin, fine particles, and other components are put into a reaction vessel such as a glass vessel. to obtain an adhesive composition.
Then, in order to remove oxygen dissolved in the adhesive composition, an inert gas such as nitrogen gas is generally supplied to purge oxygen. Then, after the adhesive composition is applied onto a release sheet or a support such as a resin film, woven fabric, or non-woven fabric, the adhesive layer is formed by irradiating with light to polymerize the polymerizable monomer. Obtainable.
It is preferable that the process from the application or impregnation of the pressure-sensitive adhesive composition to the process of irradiating with light is carried out in an inert gas atmosphere or in a state in which oxygen is blocked by a film or the like.
In this production method, the pressure-sensitive adhesive composition obtained by mixing each component may be prepolymerized before being applied to a release sheet or a support in order to increase the viscosity.

(rubber adhesive)
Next, the rubber adhesive used for the adhesive layer 11 will be described. The rubber-based adhesive contains a rubber component and a tackifying resin, and it is preferable to use a styrene-isoprene block copolymer as the rubber component. The styrene-isoprene block copolymer preferably has a diblock ratio of 25 to 70% by weight, more preferably 30 to 65% by weight, and still more preferably 45 to 60% by weight. Here, diblock means a diblock composed of styrene and isoprene. By setting the diblock ratio within the above range, it becomes easier to increase the adhesive strength. The styrene-isoprene block copolymer includes not only diblocks but also those having three or more blocks such as triblocks composed of styrene, isoprene and styrene blocks.

Although the amount of styrene in the styrene-isoprene block copolymer is not particularly limited, it is preferably 14 to 24% by mass, more preferably 15 to 18% by mass. When the styrene content is 14% by mass or more, the adhesive tends to be highly cohesive. Moreover, when it is 24% by mass or less, the cohesive force becomes an appropriate level, and the adhesive force is easily expressed.
The molecular weight of the styrene-isoprene block copolymer is not particularly limited, but the weight average molecular weight is preferably 100,000 to 400,000, more preferably 150,000 to 250,000. The term "mass average molecular weight" as used herein refers to a molecular weight measured in terms of polystyrene by GPC (gel permeation chromatography).

Various tackifying resins can be used as the tackifying resin used in the rubber-based adhesive, but petroleum-based resins, terpene resins, and coumarone resins are preferably used. The tackifying resin may be used alone or in combination of two or more. However, at least one selected from petroleum-based resins and terpene resins and coumarone resins may be used in combination. preferable. Such a combination of tackifying resins makes it easier to improve the adhesive strength.
Examples of petroleum resins include aliphatic petroleum resins (C5 petroleum resins), alicyclic petroleum resins, and aromatic petroleum resins. family-based petroleum resins are preferred. Further, it is preferable to use a petroleum-based resin having a softening point of about 90 to 120°C.
As the terpene resin, 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 preferable from the viewpoint of ensuring adhesive strength. As the coumarone resin, one having a softening point of preferably 110 to 130° C., more preferably 115 to 125° C. is used in order to ensure cohesion.

The tackifying resin is preferably 60 to 250 parts by mass, more preferably 100 to 200 parts by mass, even more preferably 110 to 180 parts by mass, based on 100 parts by mass of the rubber component. By setting the blending amount of the tackifying resin within the above range, it becomes possible to improve the cohesive force and impart an appropriate adhesive force.
When a petroleum-based resin and at least one selected from a terpene resin and a cumarone resin are used in combination, the petroleum-based resin is preferably 50 to 200 parts by mass, preferably 60 to 150 parts by mass, with respect to 100 parts by mass of the rubber component. Parts by mass are preferable, and 60 to 110 parts by mass are more preferable. 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. Furthermore, 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 pressure-sensitive adhesive may contain the fine particles described above in the same manner as the acrylic pressure-sensitive adhesive. It may contain agents, fillers, and the like.

(urethane adhesive)
The urethane-based pressure-sensitive adhesive described above is not particularly limited, and examples thereof include urethane resins obtained by reacting at least a polyol with a polyisocyanate compound. Examples of the polyols include polyether polyols, polyester polyols, polycarbonate polyols, polycaprolactone polyols, and the like. Examples of the 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.
Moreover, as the urethane-based adhesive, a urethane resin obtained by reacting a polyurethane polyol and a polyfunctional isocyanate-based curing agent may be used. Examples of the polyurethane polyol include those obtained by reacting the above-described polyol with a polyisocyanate compound, and those obtained by reacting a polyol, a polyisocyanate compound, and a chain extender such as a diamine. As the polyfunctional isocyanate-based curing agent, any compound having two or more isocyanate groups may be used, and the isocyanate compounds described above can be used.
In addition to the urethane resin, the urethane-based pressure-sensitive adhesive may contain the above-described fine particles. , antioxidants, fillers, and the like.

(Silicone adhesive)
Examples of the silicone-based pressure-sensitive adhesive include addition-reactive, peroxide-curable, and condensation-reactive silicone-based pressure-sensitive adhesives. Among them, addition reaction-type silicone pressure-sensitive adhesives are preferably used from the viewpoint that they can be cured at a low temperature in a short period of time. The addition reaction type silicone pressure-sensitive adhesive cures when the pressure-sensitive adhesive layer is formed. When an addition-reactive silicone pressure-sensitive adhesive is used as the silicone pressure-sensitive adhesive, the silicone pressure-sensitive adhesive may contain a catalyst such as a platinum catalyst.
In addition, the silicone pressure-sensitive adhesive may contain fine particles, and may contain a cross-linking agent and various additives for controlling adhesive strength.

<Storage elastic modulus G'>
The adhesive layer 11 preferably has a storage modulus G' of 50,000 to 1,000,000 Pa at 23°C. When the storage elastic modulus G' of the pressure-sensitive adhesive layer 11 at 23°C is 50,000 or more, the anti-corrosion performance is good. When the storage elastic modulus G′ at 23° C. is 50,000 or more, when the pressure-sensitive adhesive layer 11 is damaged due to an external impact or the like, the resin flows in the direction of restoring the damaged portion, and the force restores the damaged portion. (hereinafter also referred to as self-healing power) becomes stronger. As a result, it is possible to suppress deterioration in the function of preventing corrosion of the first structure 20 due to exposure of the surface of the first structure 20 or partial thinning of the pressure-sensitive adhesive layer 11 .
When the storage elastic modulus G′ at 23° C. of the anticorrosion adhesive is 1,000,000 or less, the function of preventing corrosion of the first structure 1 is improved. When the storage elastic modulus G′ at 23° C. is 1,000,000 or less, the fluidity of the resin constituting the adhesive layer 11 is high, and when the adhesive is damaged, the damaged site is easily blocked with the resin, and the self- stronger resilience. As a result, it is considered that the function of preventing corrosion of the first structure 20 is improved as in the case described above.
The adhesive layer 11 has a storage elastic modulus G′ of 50,000 to 1,000,000 Pa at 23° C., and the resin constituting the adhesive layer 11 has appropriate elasticity and viscosity. It has high self-healing power when damaged by external impact, etc., and is considered to have high anti-corrosion performance.
The storage elastic modulus G′ of the pressure-sensitive adhesive layer 11 at 23° C. is more preferably 100,000 to 800,000 Pa, still more preferably 150,000 to 600,000 Pa. When the storage elastic modulus G′ at 23° C. is within such a range, the pressure-sensitive adhesive layer 11 has a higher self-healing power and improved anti-corrosion performance.
The storage elastic modulus G 'is, for example, using DVA-200 (manufactured by IT Keisoku Co., Ltd.), shear mode: 10 Hz, strain amount: 0.1%, temperature range: -100 ° C. to 100 ° C., heating rate : It can be calculated by measuring the dynamic viscoelasticity spectrum under the condition of 10°C/min.

The thickness of the adhesive layer 11 is, for example, 20 μm or more, preferably 40 μm or more. When the thickness is 20 μm or more, it becomes possible to exhibit appropriate adhesiveness and sacrificial corrosion resistance. The pressure-sensitive adhesive layer 11 preferably has a large thickness in order to have a good self-healing function, and more preferably has a thickness of 200 μm or more. 400 μm or more is more preferable in order to The thickness of the conductive pressure-sensitive adhesive layer 11 is not particularly limited. For example, it is preferably 1 cm or less.
The thickness of the pressure-sensitive adhesive layer 11 means the thickness of each pressure-sensitive adhesive layer in the case of a double-sided pressure-sensitive adhesive tape having pressure-sensitive adhesive layers on both sides of a substrate, which will be described later.

<Anti-corrosion adhesive tape>
The anticorrosive adhesive tape 10 is preferably a double-sided adhesive tape, for example. When the double-sided adhesive tape is used, before the second structure 30 is permanently fixed to the first structure 20 using bolts or the like, the first structure 20 is attached to the first structure 20 via the anticorrosive adhesive tape 10 . 2 structures 30 can be temporarily fixed. Moreover, when the second structure is a steel structure, both the first and second structures can be protected against corrosion.
The anticorrosive pressure-sensitive adhesive tape 10 is preferably a double-sided pressure-sensitive adhesive tape consisting of only the pressure-sensitive adhesive layer (that is, the pressure-sensitive adhesive layer alone). By using the anti-corrosion pressure-sensitive adhesive tape 10 consisting only of the pressure-sensitive adhesive layer 11, the thickness of the tape can be reduced while maintaining good anti-corrosion properties.

Alternatively, as shown in FIG. 2, the anti-corrosion pressure-sensitive adhesive tape 10 may be a single-sided pressure-sensitive adhesive tape having a substrate 12 and an adhesive layer 11 provided on one side of the substrate 12 . Thereby, the adhesive layer 11 can be protected by the substrate 12 . Therefore, the durability of the anticorrosive pressure-sensitive adhesive tape 10 is further improved. Further, when the second structure 30 is a concrete structure or a mortar structure, after the anticorrosion adhesive tape 10 is attached to the first structure 20, on the anticorrosion adhesive tape 10, for example, ready-mixed concrete or Raw mortar may be poured. By providing the substrate 12 on the anticorrosion pressure-sensitive adhesive tape 10, the pressure-sensitive adhesive layer 11 can be protected from fresh concrete or fresh mortar.

Furthermore, although not shown, the anticorrosion pressure-sensitive adhesive tape may be a double-sided pressure-sensitive adhesive tape having a substrate and pressure-sensitive adhesive layers on both sides of the substrate. As in the case where the anti-corrosion adhesive tape consists only of an adhesive layer, this allows the anti-corrosion adhesive tape to be interposed before the second structure is permanently fixed to the first structure using bolts or the like. can be used to temporarily fix the second structure to the first structure.
In the double-sided pressure-sensitive adhesive tape having pressure-sensitive adhesive layers on both sides of the substrate, each pressure-sensitive adhesive layer is as described above. However, from the viewpoint of sacrificial corrosion resistance, at least the pressure-sensitive adhesive layer on the side bonded to the first structure 20 preferably contains a sacrificial corrosion-protective metal, or a sacrificial corrosion-protective metal and a conductive material, and It is preferred that the storage modulus G' be in the range as explained above.

Base materials used in each pressure-sensitive adhesive tape include, for example, sheet materials such as resin films, non-woven fabrics, and metal foils.
Examples of resin films include acrylic resin films, fluorine resin films, propylene resin films, polyethylene resin films, polyester resin films, polyamide resin films, polyacrylic resin films, polyurethane resin films, and polystyrene resin films. Resin films, polyvinyl chloride resin films, ethylene vinyl acetate resin films, acrylonitrile resin films, polycarbonate resin films and the like can be used.
The nonwoven fabric is, for example, a nonwoven fabric made of synthetic resin fibers such as polyamide, polyester, polyacrylic, polyolefin, and polyurethane fibers.
Metal foils include, for example, metal foils of iron and its alloys, metal foils of metals having a lower potential than iron such as chromium, zinc, titanium, aluminum, and magnesium, gold, silver, copper, tin, nickel, cobalt, and the like. metal foil of a metal whose potential is nobler than that of iron.
These sheet-like materials can be used individually by 1 type or in combination of 2 or more types. From the viewpoint of protecting the pressure-sensitive adhesive layer 11, the substrate is preferably a resin film. By using the resin film described above, when the second structure 30 is a concrete structure or a mortar structure, the adhesive layer can be properly protected even if freshly mixed concrete or freshly mixed mortar is poured over the resin film.
Although the thickness of the base material is not particularly limited, it is, for example, 10 to 200 μm, preferably 20 to 100 μm.

Repairs to the structure are performed while the structure is in use or while the structure is temporarily out of use. For this reason, it is necessary to finish the repair of the structure in a short working time. From this point of view, the anticorrosion pressure-sensitive adhesive tape of one embodiment of the present invention is preferably used as a repair anticorrosion material for repairing existing structures.

<Modification 1 of anticorrosion adhesive tape>
The pressure-sensitive adhesive layer 11 of the anti-corrosion pressure-sensitive adhesive tape 10 of one embodiment of the present invention preferably contains a metal having a lower potential than iron. However, the pressure-sensitive adhesive layer 11 of the anticorrosion pressure-sensitive adhesive tape 10 of one embodiment of the present invention does not need to contain a metal having a potential lower than that of iron. In this case as well, the anticorrosion adhesive tape 10 can shield the first structure from substances such as oxygen, water, and corrosive substances that affect corrosion by simply attaching it to the first structure. A second structure 30 can be placed adjacent to the first structure 20 without drying time. Therefore, even if the anticorrosive pressure-sensitive adhesive tape 10 is arranged between two structures, it can exhibit good anticorrosive properties while being excellent in work efficiency.

<Modification 2 of anticorrosion adhesive tape>
The pressure-sensitive adhesive layer 11 of the anti-corrosion pressure-sensitive adhesive tape 10 of one embodiment of the present invention preferably contains a metal having a lower potential than iron. However, the pressure-sensitive adhesive layer 11 of the anticorrosion pressure-sensitive adhesive tape 10 of one embodiment of the present invention does not need to contain a metal having a potential lower than that of iron. In this case, in order to enhance the anticorrosion property of the anticorrosion pressure-sensitive adhesive tape 10, as shown in FIG. Moreover, the metal layer 13 is preferably a layer of a metal having a lower potential than iron. Specific examples of the metal having a potential lower than that of iron are as described above, and a layer of zinc is more preferable. Specifically, the metal layer 13 may be formed by bonding a metal foil made of a metal having a lower potential than iron to the surface of the pressure-sensitive adhesive layer 11 . Alternatively, the metal layer 13 may be a metal film formed by coating the surface of the pressure-sensitive adhesive layer 11 with a metal by sputtering, vacuum deposition, or the like.

A metal layer 13 is formed directly on the adhesive layer 11 . That is, the metal having a potential lower than that of iron forming the metal layer 13 comes into contact with the pressure-sensitive adhesive layer 11 . In this way, when a metal having a potential less base than that of iron comes into contact with the adhesive layer 11, the electrons emitted when ionized can easily migrate to the adhesive layer 11. improves. Also in this case, from the viewpoint of anticorrosion properties of the anticorrosion pressure-sensitive adhesive tape 10, the pressure-sensitive adhesive layer 11 preferably contains a conductive material other than a metal having a baser potential than iron.

The thickness of the metal layer 13 is preferably 2.5 μm or more. When the thickness of the metal layer 13 is 2.5 μm or more, the metal layer 13 can sufficiently supply electrons due to the ionization of the metal in the metal layer 13 to the first structure 20 , and the anticorrosive pressure-sensitive adhesive tape 10 can maintain sufficient corrosion resistance. From the viewpoint of enhancing the anti-corrosion property of the anti-corrosion pressure-sensitive adhesive tape 10, the thickness of the metal layer 13 is more preferably 5 μm or more. In addition, from the viewpoint of ensuring the flexibility of the anticorrosive adhesive tape 10 and improving the handleability of the anticorrosive adhesive tape 10, the thickness of the metal layer 13 is preferably 200 μm or less, more preferably 100 μm or less. .

Furthermore, as shown in FIG. 4, the anti-corrosion pressure-sensitive adhesive tape 10 further comprises a substrate 12 and a metal layer 13 provided on one side of the substrate 12, and the pressure-sensitive adhesive layer 11 is provided on one side of the metal layer 13. Alternatively, the metal layer 13 may be a layer of a metal whose potential is less noble than that of iron. Since the metal layer 13 is protected by the base material 12, the anticorrosion property of the anticorrosion adhesive tape 10 can be further improved. Also in this case, from the viewpoint of anticorrosion properties of the anticorrosion pressure-sensitive adhesive tape 10, the pressure-sensitive adhesive layer 11 preferably contains a conductive material other than a metal having a baser potential than iron. At this time, the metal layer 13 may be adhered to the base material 12 with an adhesive or the like, or may be formed on the base material 12 by sputtering, vacuum deposition, or the like.

Further, when the anticorrosion pressure-sensitive adhesive tape includes a metal layer that is a layer of a metal with a potential lower than that of iron, the pressure-sensitive adhesive layer may contain a metal with a potential lower than that of iron. As a result, corrosion of the first structure can be suppressed by both the metal having a potential lower than that of iron in the metal layer and the metal having a potential lower than that of iron in the adhesive layer, so that the corrosion prevention of the adhesive tape for corrosion prevention properties can be further improved.

The anticorrosion pressure-sensitive adhesive tape of the present invention may have a release sheet attached to the surface of the pressure-sensitive adhesive layer. The release sheet may be peeled off from the adhesive layer before using the anticorrosive adhesive tape to expose the adhesive layer, and the exposed adhesive layer may be attached to the structure. For example, in a double-sided pressure-sensitive adhesive tape, a release sheet may be attached to both sides of the tape, or a release sheet may be attached to only one side of the tape. In the case of a single-sided pressure-sensitive adhesive tape, it is preferable that a release sheet is attached to one side of the exposed pressure-sensitive adhesive layer.
As the release sheet, a resin film is preferably used, and it is preferable that the surface to be bonded to the pressure-sensitive adhesive layer is a release-treated surface subjected to a release treatment with a silicone release agent or the like.

Since the anticorrosive adhesive tape of one embodiment of the present invention is only one embodiment of the anticorrosive adhesive tape of the present invention, the anticorrosive adhesive tape of one embodiment of the present invention is the anticorrosive adhesive tape of the present invention. not limited to

[Corrosion prevention method for steel structures]
The corrosion prevention method for a steel structure of the present invention comprises a step of applying the anticorrosion adhesive tape of the present invention to a first structure (first step), and attaching the anticorrosion adhesive tape between the first and second structures. A step of placing at least one of the first and second structures in position (second step). As a result, the efficiency of the anti-corrosion work of the steel structure is improved, and the anti-corrosion property of the anti-corrosion material placed between the two structures can be improved while the work efficiency is excellent. .

The first and second steps are preferably performed in this order. That is, the anticorrosive adhesive tape of the present invention is attached to the first structure, and then at least one of the first and second structures is moved to attach the anticorrosive adhesive tape to the first structure. is preferably arranged so that the second structure is adjacent to the . Specifically, the second structure may be arranged on the anticorrosion adhesive tape attached to the first structure, or the second structure may be placed next to the anticorrosion adhesive tape attached to the first structure. structures may be placed. Furthermore, the second structure may be placed under the anti-corrosion adhesive tape attached to the first structure. At this time, it is preferable to place the second structure in contact with the anticorrosive adhesive tape attached to the first structure. Alternatively, the second structure may be installed by pouring ready-mixed concrete or ready-mixed mortar onto the anticorrosive adhesive tape attached to the first structure.

Moreover, you may perform a said 1st and 2nd process simultaneously in parallel. Specifically, in the case of a double-sided adhesive tape, the anticorrosive adhesive tape is first attached to the second structure. Next, at least one of the first and second structures is moved and installed at a predetermined position, and the anticorrosive adhesive tape attached to the second structure is further attached to the first structure. mating so that the anticorrosive adhesive tape is positioned between the first and second structures. At this time, the positional relationship between the first and second structures is not particularly limited. A second structure may be arranged, or the first and second structures may be arranged laterally adjacent.

In addition, since the first structure and the second structure in the corrosion prevention method for steel structures of the present invention have already been described in the item of the anticorrosion adhesive tape of one embodiment of the present invention, the first structure and the second structure Description of the second structure is omitted.

After placing the anti-corrosion adhesive tape between the first and second structures, the second structure is fixed to the first structure, usually using fixing members such as bolts and rivets. be. In addition, when the anticorrosion adhesive tape is a double-sided adhesive tape, the anticorrosion adhesive tape is arranged between the first and second structures so that the second structure is the same as the first structure. will be temporarily fastened to Then, using the fixing member, the second structure is firmly fixed to the first structure.
Further, the method for preventing corrosion of steel structures of the present invention is preferably carried out when repairing structures as described above.

EXAMPLES The present invention will be described in more detail below using examples, but the present invention is not limited to these examples.

<Evaluation method>
In Examples and Comparative Examples, the anticorrosive pressure-sensitive adhesive tapes were evaluated by the following evaluation methods.
(Drying time)
The time from when the anticorrosion adhesive tape was attached to the steel material to when the mortar plate was placed on the adhesive tape attached to the steel material was measured. Then, the drying time was evaluated according to the following evaluation criteria.
○: 0 hours ×: more than 0 hours

(Corrosion resistance evaluation)
A sample for cyclic corrosion test was prepared by attaching an anti-corrosion adhesive tape to a steel material and placing a mortar plate on the adhesive tape attached to the steel material. For the obtained cyclic corrosion test sample, JIS K5600-7-9 (Paint general test method-Part 7: Long-term durability of coating film-Section 9: Cyclic corrosion test method-Salt water spray / dry / wet , cycle D). After the cyclic corrosion test was performed for 168 hours (28 cycles), the appearance of the cyclic corrosion test samples was observed, and the corrosion resistance was evaluated according to the following evaluation criteria.
○: No rust on steel ×: Rust on steel

(storage modulus)
The storage elastic modulus of the adhesive layer of the anticorrosion adhesive tape is measured using a dynamic viscoelasticity measuring device (manufactured by IT Instrument Control Co., Ltd., trade name "DVA-200"), shear mode: 10 Hz, strain amount: 0 .1%, temperature range: -100°C to 100°C, temperature increase rate: 10°C/min. In addition, in the case of the anticorrosion pressure-sensitive adhesive tape provided with a base material, the storage elastic modulus of the pressure-sensitive adhesive layer was measured after the base material was peeled off from the pressure-sensitive adhesive layer.

[Example 1]
Adhesive composition 1 was prepared according to the formulation shown in Table 1. The adhesive composition was purged with nitrogen to remove dissolved oxygen. Then, a 600 μm-thick spacer was placed on the release-treated surface of the release sheet, and the pressure-sensitive adhesive composition was applied onto the release-treated surface of the release sheet. Then, another release sheet was coated on the applied pressure-sensitive adhesive composition so that the release-treated surface was in contact with the pressure-sensitive adhesive composition. As the release sheet, a PET film (thickness: 50 μm) subjected to silicone release treatment was used.
In this state, the intensity of the chemical lamp was adjusted so that the UV irradiation intensity on the release sheet on the coating side was 5 mW/cm ² , and the UV light was irradiated from one side for 15 minutes. An anti-corrosion double-faced pressure-sensitive adhesive tape with a release sheet attached was obtained. The thickness of the adhesive layer (that is, double-sided adhesive tape) was 600 µm. Table 2 shows the results.

[Example 2]
An anticorrosive double-sided pressure-sensitive adhesive tape was obtained in the same manner as in Example 1 except that the pressure-sensitive adhesive composition 2 was prepared according to the formulation shown in Table 1. Table 2 shows the results.

[Example 3]
A double-faced pressure-sensitive adhesive tape for corrosion protection was obtained in the same manner as in Example 1, except that a 200 μm spacer was used instead of the 600 μm thick spacer. Table 2 shows the results.

[Example 4]
A double-faced pressure-sensitive adhesive tape for anticorrosion was obtained in the same manner as in Example 1 except that a 50 μm spacer was used instead of the 600 μm thick spacer. Table 2 shows the results.

[Example 5]
An adhesive composition was applied. Next, on top of the adhesive composition 1 applied on the release-treated surface of the release sheet, an acrylic resin film (trade name "Acryprene HBS027E", manufactured by Mitsubishi Chemical Corporation) was coated instead of coating another release sheet. did. Other than that was carried out in the same manner as in Example 1 to obtain an anti-corrosion single-sided pressure-sensitive adhesive tape. Table 2 shows the results.

[Example 6]
Adhesive composition 3 was prepared according to the formulation shown in Table 1, and zinc foil (product "Zinc Foil" (manufactured by Takeuchi Metal Foil & Powder Co., Ltd.). Other than that was carried out in the same manner as in Example 1 to obtain an anti-corrosion single-sided pressure-sensitive adhesive tape. Table 2 shows the results.

[Comparative Examples 1 and 2]
Instead of the anticorrosion double-sided adhesive tape, an anticorrosion paint (trade name “Zettal EP-2”, manufactured by Dainippon Toryo Co., Ltd.) was applied to form a coating film. Table 2 shows the results.

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 Crosslinking agent: trade name "TEAI-1000", tackifier 1 manufactured by Nippon Soda Co., Ltd. : Product name “Arcon P140”, manufactured by Arakawa Chemical Industries, Ltd., hydrogenated petroleum resin, softening point 140 ° C.
Tackifier 2: Product name "Arcon 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 Metal having a lower potential than iron (zinc particles): manufactured by Sakai Chemical Industry Co., Ltd., trade name “zinc powder #40”, average grains Diameter: 50 μm
Conductive material (CNT): carbon nanotube (CNT), manufactured by JEIO, trade name “JENOTUBE8A”, average diameter 6 to 9 nm, average length 100 to 200 μm
Dispersant: Sekisui Chemical Co., Ltd., trade name "S-Lec BX-L", polyvinyl butyral resin Polymerization initiator: 2,2-dimethoxy-2-phenylacetophenone

The anticorrosion pressure-sensitive adhesive tapes of Examples 1 to 6 were excellent in both work efficiency and anticorrosion properties. On the other hand, the coating film of Comparative Example 1 had good workability but poor corrosion resistance. Also, the coating film of Comparative Example 2 had good corrosion resistance, but poor workability.

REFERENCE SIGNS LIST 10 anticorrosive adhesive tape 11 adhesive layer 12 base material 13 metal layer 20 first structure 30 second structure

Claims (12)

used by being disposed between the first structure and the second structure;
wherein the first structure is a steel structure;
An anti-corrosion adhesive tape having an adhesive layer. The second structure is selected from the group consisting of a concrete structure, a mortar structure, a steel structure, a metal structure other than steel, a thermoplastic resin structure, a thermosetting resin structure, and a fiber-reinforced plastic structure. The anticorrosion pressure-sensitive adhesive tape according to claim 1, which is at least one selected structure. The anticorrosion pressure-sensitive adhesive tape according to claim 1 or 2, comprising only the pressure-sensitive adhesive layer. The anticorrosion pressure-sensitive adhesive tape according to any one of claims 1 to 3, wherein the pressure-sensitive adhesive layer contains a metal having a potential lower than that of iron. The anticorrosive pressure-sensitive adhesive tape according to any one of claims 1 to 4, further comprising a substrate, and the pressure-sensitive adhesive layer is provided on one side of the substrate. 6. The anticorrosive pressure-sensitive adhesive tape according to claim 5, wherein the base material is at least one sheet material selected from the group consisting of resin films, nonwoven fabrics, and metal foils. further comprising a metal layer, wherein the pressure-sensitive adhesive layer is provided on one side of the metal layer,
3. The anticorrosive pressure-sensitive adhesive tape according to claim 1, wherein said metal layer is a layer of a metal having a potential lower than that of iron. 8. The anticorrosive pressure-sensitive adhesive tape according to claim 4 or 7, wherein said metal having a potential lower than that of iron is zinc. 9. The anticorrosion pressure-sensitive adhesive tape according to any one of claims 4, 7 and 8, wherein the pressure-sensitive adhesive layer contains a conductive material other than a metal having a potential lower than that of iron. 10. The anti-corrosion pressure-sensitive adhesive tape according to claim 9, wherein said conductive material is carbon nanotubes. The anticorrosion pressure-sensitive adhesive tape according to any one of claims 1 to 10, wherein the pressure-sensitive adhesive layer has a storage elastic modulus G' of 50,000 to 1,000,000Pa at 23°C. A step of applying the anticorrosive adhesive tape according to any one of claims 1 to 11 to the first structure, and the anticorrosive adhesive tape is arranged between the first and second structures A method for preventing corrosion of a steel structure, comprising the step of installing at least one of said first and second structures in such a way as to prevent corrosion.

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