JP2018030963A - Adhesive sheet, and reinforcement method using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an adhesive sheet having an adhesion part to be cured due to moisture.SOLUTION: The present invention provides an adhesive sheet 10 having an adhesion part 1 to be cured due to moisture absorption, the adhesive sheet including an epoxy resin, an acrylic resin, and a curing agent as a ketimine compound produced from a condensation reaction between an amine having a primary amino group and a diethyl ketone.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to an adhesive sheet and a reinforcing method using the same.

  In recent years, development of a technique for firmly bonding an adherend and an adhesive layer has been demanded. As an adhesive used for the adhesive layer, for example, a liquid adhesive is known. For example, as disclosed in Patent Documents 1 and 2, such a liquid adhesive reacts by mixing a one-component adhesive that starts reaction due to moisture in the air or a main agent and a curing agent. There is a two-part adhesive that begins.

  On the other hand, when a liquid adhesive is used, there are problems such as dripping and difficulty in uniform application. In addition, when using a two-component adhesive, there is a problem that it is particularly necessary to mix the main agent and the curing agent, which takes time for the user. Therefore, a technique using a double-sided tape instead of a liquid adhesive has been proposed, but since a pressure-sensitive adhesive is usually used for a double-sided tape, it is strong for a long time as in the case of using an adhesive. There is a problem that difficult adhesion is difficult.

  For such a problem, for example, an adhesive sheet using an adhesive having predetermined tackiness and adhesiveness has been proposed. Since the adhesive sheet has a predetermined tackiness in the initial stage, the adhesive sheet can be positioned before curing. Therefore, it is possible to suppress the occurrence of positional deviation of the adhesive sheet. For example, Patent Document 3 discloses an adhesive sheet that is cured by photopolymerization and moisture, and Patent Document 4 discloses an adhesive sheet that is cured by ultraviolet light.

JP 2000-265121 A JP 11-131823 A JP 2000-273418 A International Publication No. 2015/159733

  By the way, since the adhesive sheet disclosed in Patent Documents 3 and 4 is cured by irradiation with sunlight, ultraviolet rays or the like, the adhesive sheet is used in a tunnel where light does not radiate, or at night. When using an adhesive sheet, an illuminating device for proceeding with the curing of the adhesive sheet is required. Moreover, when the area | region which bonds an adhesive sheet spreads over a wide range, time and an effort will be required for hardening of the adhesive sheet using an illuminating device.

  This indication is made | formed in view of the said situation, and it aims at providing the adhesive sheet which has an adhesive part hardened | cured with moisture.

  The present disclosure is an adhesive sheet having an adhesive part that is cured by moisture absorption, wherein the adhesive part includes an epoxy resin, an acrylic resin, and a curing agent. Provided is an adhesive sheet characterized by being a ketimine compound produced by a condensation reaction between an amine having a secondary amino group and diethyl ketone.

  The present disclosure is a reinforcing method for reinforcing an adherend using an adhesive sheet having an adhesive part that is cured by moisture absorption, and the step of preparing the adhesive sheet having the adhesive part And the step of bonding the adhesive portion of the adhesive sheet to the surface of the adherend, and the surface opposite to the surface of the adhesive portion bonded to the adherend A step of curing the adhesive portion in a state where the adhesive is exposed. The adhesive portion includes an epoxy resin, an acrylic resin, and a curing agent. The curing agent is a primary amino acid. Provided is a reinforcing method characterized by being a ketimine compound produced by a condensation reaction between an amine having a group and diethyl ketone.

  The present disclosure has an effect of providing an adhesive sheet having an adhesive part that is cured by moisture.

It is a schematic sectional drawing which shows an example of the adhesive sheet | seat of this indication. It is a schematic sectional drawing which shows the other example of the adhesive sheet | seat of this indication. It is a schematic process drawing which shows an example of the reinforcement method of this indication.

  The present disclosure relates to an adhesive sheet that is cured by moisture absorption. Here, in the case of an adhesive sheet that cures due to moisture absorption, predetermined sheet stability is required. Specifically, when the reactivity of the pressure-sensitive adhesive sheet due to moisture absorption is too high, the pressure-sensitive adhesive sheet reacts with slight moisture, which may make it difficult to store the pressure-sensitive adhesive sheet. On the other hand, when the reactivity of the adhesive sheet due to moisture absorption is too low, there is a possibility that problems such as the curing of the adhesive sheet not progressing.

  On the other hand, in the present disclosure, the adhesive portion in the adhesive sheet has an epoxy resin, an acrylic resin, and a curing agent, and the curing agent is an amine having a primary amino group and diethyl ketone. By the ketimine compound produced | generated by a condensation reaction, it can be set as the adhesive sheet | seat which has the outstanding sheet stability. The reason can be considered as follows.

  First, it is considered that curing of the adhesive portion by moisture absorption proceeds as follows. That is, when the adhesive part is exposed to moisture, the ketimine compound contained in the adhesive part reacts with water to produce amine and diethyl ketone, and the amine produced at this time is combined with the epoxy resin. Curing proceeds by reacting. If it does so, in order to suppress the reactivity of the adhesive sheet by moisture absorption, it is necessary to suppress the reactivity of a ketimine compound and water. In the present disclosure, the ketimine compound is a product obtained by a condensation reaction between an amine having a primary amino group and diethyl ketone, and has an appropriate steric hindrance so that the sheet stability of the adhesive sheet can be maintained. Have Therefore, in the present disclosure, when the adhesive part is exposed to moisture, the reactivity between the ketimine compound and water can be suppressed, and an adhesive sheet having excellent sheet stability can be obtained. it is conceivable that.

  Hereinafter, the adhesive sheet of the present disclosure will be described.

A. Adhesive sheet The adhesive sheet of the present disclosure is an adhesive sheet having an adhesive part that is cured by moisture absorption, and the adhesive part includes an epoxy resin, an acrylic resin, and a curing agent. The curing agent is a member characterized by being a ketimine compound produced by a condensation reaction between an amine having a primary amino group and diethyl ketone.

The adhesive sheet of the present disclosure will be described with reference to the drawings.
Drawing 1 (a) and (b) is a schematic sectional view showing an example of an adhesive sheet of this indication. As shown in FIG. 1A, the adhesive sheet 10 of the present disclosure may have the adhesive 2 that cures by moisture absorption and the separator 2 on one surface of the adhesive 1. Alternatively, as shown in FIG. 1B, separators 2a and 2b may be provided on both surfaces of the adhesive portion 1 and the adhesive portion 1 that are cured by moisture absorption. Moreover, the adhesive part 1 in this indication has an epoxy resin, an acrylic resin, and a hardening | curing agent, Furthermore, a hardening | curing agent produces | generates by the condensation reaction of the amine which has a primary amino group, and diethyl ketone. It is a ketimine compound.

Since the adhesive sheet of the present disclosure has a predetermined adhesive part, it can be cured by moisture absorption, and excellent sheet stability can be obtained. Note that the detailed description can be the same as that described above, and thus the description thereof is omitted here.
Hereinafter, the adhesive sheet of the present disclosure will be described.

1. Adhesive part The adhesive part in this indication is a member hardened by moisture absorption. Moreover, an adhesive bond part is a member which has an epoxy resin, an acrylic resin, and a hardening | curing agent. In addition, hereinafter, when simply referred to as an adhesive part, it means an adhesive part before curing unless there is an explanation that it is after curing.
Hereinafter, materials and physical properties of the adhesive portion will be described.

(1) Material The adhesive part in this indication is a member which has an epoxy resin, an acrylic resin, and a hardening agent. Specifically, the adhesive portion in the present disclosure is a member composed of a moisture curable resin composition having an epoxy resin, an acrylic resin, and a curing agent. Hereinafter, the epoxy resin, the acrylic resin, and the curing agent included in the moisture curable resin composition may be simply described as an epoxy resin, an acrylic resin, and a curing agent included in the adhesive portion.
Hereinafter, each material will be described.

(A) Curing Agent The curing agent contained in the adhesive portion in the present disclosure is a ketimine compound generated by a condensation reaction between an amine having a primary amino group and diethyl ketone.

  The amine having a primary amino group constituting the curing agent in the present disclosure is not particularly limited as long as a desired curing agent can be generated by a condensation reaction with diethyl ketone described later. For example, ethylenediamine, diethylenetriamine, 1,3-bisaminomethylcyclohexane, norbornanediamine, metaxylylenediamine, isophoronediamine, bis (4-aminocyclohexyl) methane, polyamine having a polyoxylene skeleton, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltriethoxysilane, and the like. . In the present disclosure, an amine having two or more primary amino groups in one molecule is preferable from the viewpoint of obtaining excellent mechanical strength.

  Diethyl ketone constituting the curing agent in the present disclosure has a structure as shown in the following formula (1).

  The ketimine compound used as a curing agent in the present disclosure can be generated by a condensation reaction between the above-described amine having a primary amino group and diethyl ketone, and the specific generation method is not particularly limited. In addition, since the ketimine compound in this indication can be produced | generated using the method similar to the method described in patent 3404390, description here is abbreviate | omitted.

  Content of the hardening | curing agent in an adhesion part can be made into the quantity according to the amino value of a ketimine compound with respect to an epoxy resin, for example. Specifically, it is preferably contained in the range of 1 to 100 parts by weight with respect to 100 parts by weight of the epoxy resin. When the content of the ketimine compound has the above lower limit, it is possible to suppress the occurrence of problems such as a decrease in adhesive strength and heat resistance after curing. On the other hand, when the content of the ketimine compound has the above upper limit, it is possible to suppress the occurrence of problems such as a decrease in reactivity and insufficient progress of curing, and as a result, it is possible to suppress a decrease in heat resistance. . In addition, content of the hardening | curing agent here points out content of the hardening | curing agent in the adhesive bond part before hardening.

(B) Epoxy resin The epoxy resin contained in the adhesive part in the present disclosure reacts with the amine decomposed from the above-described curing agent when the adhesive part is exposed to moisture, thereby causing an adhesive part. It is preferable that the curing of the resin proceeds. The epoxy resin preferably contains two or more epoxy groups in the molecule. Moreover, the epoxy resin may be contained individually by 1 type and 2 or more types may be contained. Examples of such an epoxy resin include a liquid epoxy resin and a solid epoxy resin.

(I) Liquid epoxy resin The liquid epoxy resin in the present disclosure preferably has a mass average molecular weight (Mw) of 300 or more and 2000 or less. When the mass average molecular weight of the liquid epoxy resin is within the above range, the compatibility with the acrylic resin described above can be improved. Moreover, it can be set as the adhesive part which has high durability and can exhibit high adhesiveness because the mass average molecular weight of a liquid epoxy resin is in the said range. Furthermore, the epoxy equivalent (g / eq.) Of the liquid epoxy resin is preferably 100 or more and less than 800. In addition, an epoxy equivalent is the gram number of resin containing the epoxy group of 1 gram equivalent measured by the method based on JISK7236.

  Such a liquid epoxy resin is not particularly limited as long as it is a liquid epoxy resin at room temperature, for example, and various epoxy resins can be used. Specifically, bisphenol A type epoxy resin, bisphenol F type epoxy resin, biphenyl type epoxy resin, hydrogenated bisphenol A type epoxy resin, aliphatic type epoxy resin, stilbene type epoxy resin, orthocresol novolak type epoxy resin, phenol novolak Type epoxy resin, modified phenol type epoxy resin, triphenol methane type epoxy resin, alkyl modified triphenol methane type epoxy resin, triazine nucleus-containing epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, dicyclopentadiene modified phenol type The 1 type (s) or 2 or more types chosen from an epoxy resin, a glycidyl amine type epoxy resin, etc. are mentioned.

  Among these, bisphenol type epoxy resins such as bisphenol A type epoxy resin and bisphenol F type epoxy resin can improve mechanical strength, curability, heat resistance, adhesiveness, and the like, and can be preferably used. In particular, a bisphenol A type epoxy resin can be preferably used. Of these bisphenol A type epoxy resins, those containing 1 or more and 3 or less of the bisphenol skeleton of the main chain are preferably used because they are liquid at room temperature. In addition, normal temperature here means 23 +/- 2 degreeC.

  The content of the liquid epoxy resin in the adhesive part can be appropriately adjusted according to the material contained in the adhesive part, for example, 20 mass relative to the total amount of the liquid epoxy resin and the solid epoxy resin. % Or more, preferably 25% by mass or more. Moreover, it is preferable that content of a liquid epoxy resin is 90 mass% or less with respect to the total amount of a liquid epoxy resin and a solid epoxy resin, and it is preferable that it is 85 mass% or less especially. When the content of the liquid epoxy resin is within the above range, desired tackiness can be imparted to the adhesive portion.

(Ii) Solid epoxy resin The solid epoxy resin in the present disclosure preferably has a mass average molecular weight (Mw) of 300 or more, and more preferably 800 or more. The solid epoxy resin preferably has a mass average molecular weight (Mw) of 6000 or less, more preferably 3000 or less. When the mass average molecular weight of the solid epoxy resin is within the above range, the compatibility with the acrylic resin described above can be improved. Moreover, when the mass average molecular weight of the solid epoxy resin is within the above range, in the adhesive layer forming step described later, the adhesive layer has high durability and can exhibit high adhesiveness. can do. Furthermore, the epoxy equivalent (g / eq.) Of the solid epoxy resin is preferably 100 or more and 5200 or less.

  Such a solid epoxy resin is not particularly limited as long as it is a solid epoxy resin at room temperature, for example, and various epoxy resins can be used. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, orthocresol novolac type epoxy resin, phenol novolac type epoxy resin, modified phenol type epoxy resin, naphthalene type epoxy resin, triphenolmethane type epoxy resin, alkyl modified triphenolmethane Type epoxy resin, triazine nucleus-containing epoxy resin, dicyclopentadiene type epoxy resin, glycidylamine type epoxy resin, biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin, hydrogenated bisphenol A type epoxy resin, aliphatic type epoxy resin, stilbene type One type or two or more types selected from an epoxy resin and a bisphenol A novolak type epoxy resin can be used.

  Among these, bisphenol type epoxy resins such as bisphenol A type epoxy resin and bisphenol F type epoxy resin can be more preferably used from the viewpoints of mechanical strength, curability, heat resistance, adhesiveness, and the like. Resins can be particularly preferably used. In the case of a bisphenol A type epoxy resin, those having a main chain bisphenol skeleton of 2 or more and 10 or less are usually solid at room temperature.

  The content of the solid epoxy resin in the adhesive part can be appropriately adjusted according to the material contained in the adhesive part. In addition, about specific content of a solid epoxy resin, since it can be set as the same as the liquid epoxy resin mentioned above, description here is abbreviate | omitted.

(C) Acrylic resin The acrylic resin in this indication can improve the film-forming nature at the time of forming an adhesive sheet using an adhesive part. In the present disclosure, the concentration of the above-described epoxy resin tends to be relatively lowered due to the adhesive portion including the acrylic resin. Therefore, the acrylic resin has an action of delaying the curing reaction by reacting with the amine produced by the epoxy resin with water. Therefore, the sheet stability of the adhesive sheet can be enhanced by having the acrylic adhesive in the adhesive part.

  The acrylic resin in the present disclosure preferably has a cured mass average molecular weight (Mw) of 150,000 or more, and more preferably 400,000 or more. The acrylic resin preferably has a mass average molecular weight (Mw) of 1,500,000 or less, more preferably 1,200,000 or less. When the mass average molecular weight of the acrylic resin is within the above range, the adhesiveness of the adhesive portion can be easily adjusted, and the cohesive force of the adhesive portion can be increased. The mass average molecular weight is a value in terms of polystyrene when measured by gel permeation chromatography (GPC).

  As such an acrylic resin, for example, an acrylate copolymer can be used. As the monomer component of the acrylate copolymer, methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, isobutyl acrylate, n-hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, acrylic acid Acrylic acid ester monomers such as lauryl; maleic acid, itaconic acid, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, acrylamide, N-methylolacrylamide, n-butoxy-N-methylolacrylamide, 2-acrylamide-2- Functional group-containing monomers such as sodium methyl-1-propanesulfonate, diacetone acrylamide, glycidyl acrylate; styrene, vinyl toluene, vinyl acetate, acrylonitrile, vinyl chloride, vinyl chloride Down, monomers such as ethyl vinyl ether; and the like. The acrylic ester copolymer is a copolymer of these monomer components.

Among these monomer components, an acrylate copolymer having a monomer component such as an epoxy group, a hydroxyl group, a carboxyl group, or a nitrile group as a functional group is preferable. Specific examples include an ethyl acrylate-butyl acrylate-acrylonitrile copolymer, an ethyl acrylate-acrylonitrile copolymer, and a butyl acrylate-acrylonitrile copolymer. By using such an acrylic resin, it becomes possible to further improve the adhesion to the adherend.
Here, “acrylic acid” such as methyl acrylate and ethyl acrylate includes “methacrylic acid” such as methyl methacrylate and ethyl methacrylate.

  Moreover, as an acrylic ester copolymer, a block copolymer is mentioned, for example. Among these, a triblock copolymer containing methacrylate-acrylate-methacrylate is preferable. Examples of the methacrylate constituting the triblock copolymer include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, and benzylid methacrylate. It is done. Examples of the acrylate constituting the triblock copolymer include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, and benzylid acrylate. Is mentioned. Specific examples of the triblock copolymer composed of methacrylate-acrylate-methacrylate include, for example, methyl methacrylate-butyl acrylate-methyl methacrylate triblock copolymer.

  In the present disclosure, the acrylic resin preferably contains methyl methacrylate called MMA. Among these, in the present disclosure, the acrylic resin is preferably a methyl methacrylate-butyl acrylate-methyl methacrylate triblock copolymer called MMA-BA-MMA. Such a block copolymer exhibits sufficient adhesion to the adherend and is also preferable from the viewpoint of improving heat resistance.

  The content of the acrylic resin in the adhesive part can be appropriately adjusted according to the material contained in the adhesive part. For example, the content is 4% by mass or more with respect to the total amount of the acrylic resin and the epoxy resin. It is preferable that it is 5% by mass or more. Moreover, it is preferable that content of an acrylic resin is 50 mass% or less with respect to the total amount of an acrylic resin and an epoxy resin, and it is preferable that it is 34 mass% or less especially. When the content of the acrylic resin is within the above range, desired tackiness can be imparted to the adhesive portion.

(D) Core material The adhesive part in this indication may have a core material if needed.

  FIG. 2 is a schematic cross-sectional view illustrating another example of the adhesive sheet of the present disclosure. In the adhesive sheet 10 of the present disclosure, the adhesive part 1 may have a core material 4 as shown in FIG. The core material 4 may be disposed inside the adhesive part 1 or may be impregnated in the adhesive part 1. Since the adhesive part has a core material, when a part of the adherend is peeled off, the peeled adherend piece can be supported by the adhesive part, providing repair and reinforcement functions. It becomes possible to do.

  The strength of the core material is appropriately changed according to the type of adherend to which the adhesive sheet is bonded. For example, when the adherend is concrete such as a road, In the punching test stipulated by the Japan Highway Public Corporation (East Japan Expressway Co., Ltd., Central Japan Expressway Co., Ltd., West Japan Expressway Co., Ltd.), the punching strength of the adhesive part after curing is within the desired range. It is preferable. Since the punching strength of the adhesive part after curing will be described in the section of “(2) Physical Properties” described later, description thereof is omitted here.

  Examples of the material for the core material include one or more selected from polyester fiber, polyamide fiber, aramid fiber, vinylon fiber, carbon fiber, glass fiber, polyolefin fiber, and the like. Among these, polyester fiber, polyamide fiber, aramid fiber, vinylon fiber, and polyolefin fiber are preferably used because they are light and excellent in strength. These fibers may be blended, used separately for warp and weft, or laminated in multiple layers. In addition, reinforcement includes repairs that conceal cracks or erase unevenness, and further includes those that provide functions such as strength improvement, water retention, surface protection, and decoration.

  Moreover, sheet-like members, such as a waterproof sheet, a water absorbing sheet, an ultraviolet-resistant sheet, a water retention sheet | seat, a coloring sheet | seat, can be used for a core material. In addition, such a sheet-like member and a member containing the above-described fiber material can be used in combination for the core material.

  When the core material is disposed inside the adhesive portion, the thickness of the core material is not particularly limited as long as the core material can exhibit the function as the core material. It is preferably within a range of 0.0 mm or less.

(E) Other materials In addition to the materials described above, other materials can be used as necessary for the adhesive portion. Other materials include, for example, crosslinking agents, polymerization catalysts, tackifiers, hardeners, softeners, fillers, plasticizers, solvents, antioxidants, curing accelerators, inorganic particles such as silica and flame retardants, Examples include thickeners, heat dissipation agents, insulating agents, and conductive agents.

  Moreover, the adhesive part may contain the pigment as needed. By including the pigment, the ultraviolet light incident on the adhesive part can be absorbed by the pigment, and deterioration of the adhesive part due to the ultraviolet light can be suppressed. An example of such a pigment is carbon black.

(2) Physical property The adhesive part in this indication is a member which shows adhesiveness. Here, “adhesiveness” means to exhibit predetermined adhesiveness and adhesiveness. Specifically, the adhesive part in the present disclosure exhibits a predetermined adhesiveness to the adherend to which the adhesive sheet is bonded, and is cured by moisture absorption, thereby adhering to the adherend. Indicates a predetermined adhesiveness. Adhesion is used to mean a temporary adhesion phenomenon, whereas adhesion is sometimes used to mean a permanent adhesion phenomenon (Iwanami Shoten RIKEN Dictionary 5th edition). ).

  The “predetermined tackiness” indicated by the adhesive part is not particularly limited because it can be appropriately adjusted according to the type of adherend. For example, an adhesive sheet is bonded to the adherend. In addition, it is preferable to exhibit a degree of tackiness that can suppress the occurrence of misalignment or peeling of the adhesive sheet. Among them, when the adherend surface to which the adhesive sheet is bonded is a vertical surface or a normal surface, for example, when bonding to a tunnel wall or ceiling, the adhesive portion should exhibit high tackiness. Is preferred. Specifically, the tackiness exhibited by the adhesive portion is preferably in the range of 0.05 N / inch to 50 N / inch, and more preferably in the range of 0.1 N / inch to 40 N / inch. Preferably there is. When the tackiness exhibited by the adhesive part is within the above range, the adhesive sheet can be bonded to the adherend, and the occurrence of positional deviation or peeling of the adhesive sheet can be suppressed. Moreover, the state which bonded the adhesive sheet to the to-be-adhered body can be hold | maintained until it pastes an adhesive sheet to an to-be-adhered body, and hardens an adhesive part, predetermined | prescribed holding | maintenance Characteristics can be shown. The retention period can be approximately one year.

  Further, when the tackiness of the adhesive part is in the range of 0.05 N / inch or more and 20 N / inch or less, especially when it is in the range of 0.1 N / inch or more and 10 N / inch or less, The wearing part can exhibit low adhesiveness. Therefore, after bonding the adhesive sheet to the adherend, the adhesive sheet can be peeled off and re-applied.

  The tackiness of the adhesive part can be measured using the following method. First, an adhesive sheet provided with a separator on one surface of the adhesive part is cut into a size of 25.4 mm in length and 150 mm in width, and the opposite side to the side on which the separator is provided, that is, the adhesive sheet. A PET film (A4100 manufactured by Toyobo Co., Ltd.) is bonded to the surface where the adhesive portion is exposed using a manual roller. Thereafter, an SUS plate (304BA, adherend surface: polished surface, sample: 25.4 mm long, 150 mm wide) is bonded to the adhesive part exposed by peeling the separator using a manual roller. Then, the adhesive part with PET film is peeled off by hand about 20 mm from the SUS plate, and conforms to JIS Z0237 using a tensile tester (manufactured by A & D Co., Ltd., model number: RTF-1150H). The adhesive strength (N / inch) with respect to the SUS plate surface can be measured under the conditions (tensile speed: 300 mm / min, peel distance: 150 mm, peel angle: 180 °). One inch is 25.4 mm.

  Moreover, the holding | maintenance characteristic of an adhesive bond part can be measured using the following methods. First, an adhesive sheet provided with a separator on one surface of the adhesive part is cut into a size of 25 mm in length and 12.5 mm in width, and the surface opposite to the side on which the separator is provided, that is, adhesive The surface with the exposed exposed portion is attached to the tip of one iron plate (hot dip galvanized steel plate, length 100 mm, width 25 mm, thickness 1.5 mm) which is an adherend. Next, the tip of another iron plate (length 100 mm, width 25 mm, thickness 1.5 mm) as an adherend is attached to the adhesive portion exposed by peeling the separator from the adhesive sheet attached to the iron plate. Paste the part. Next, one adherend is temporarily fixed, a load of 200 g is applied, a temperature of 23 ° C. and a humidity of 50% RH (hereinafter sometimes referred to as a 23 ° C. and 50% RH environment), shearing, and the like. Check whether it can be held without any problems. The time during which the holding can be performed without shearing can be set as the time during which the adhesive portion can exhibit the holding characteristics. For the measurement, for example, a holding power tester such as BE-501 manufactured by Tester Sangyo Co., Ltd. can be used.

  The level of tackiness of the adhesive part can be evaluated by loss tangent. That the adhesive part exhibits low viscosity means that the loss tangent at 23 ° C. of the adhesive part is 0.2 or less, and more preferably 0.1 or less. In addition, the phrase “viscous adhesion part exhibits high viscosity” means that the loss tangent at 23 ° C. of the adhesive adhesion part is 0.5 or more, and more preferably 1.0 or more. The tackiness of the adhesive part can be adjusted as appropriate according to the composition and blending ratio of the material constituting the adhesive part. For example, the tackiness can be adjusted by adjusting the epoxy equivalent of the epoxy resin contained in the adhesive part and the amine value in the ketimine compound that is a curing agent. The loss tangent can usually be expressed as “tan δ”.

  Tan δ is one of the parameters that reflect the viscosity of the adhesive layer and exhibit stress relaxation behavior. Here, “stress relaxation behavior” refers to a delay in deformation when a force is applied. For example, tan δ is a dynamic viscoelasticity measurement method (attachment mode: compression mode, frequency) based on JIS K7244-1, using a solid viscoelasticity analyzer RSA-III manufactured by TA Instruments as a measuring device. 1 Hz, temperature: −50 ° C. to 150 ° C., temperature rising temperature: 5 ° C./min).

  The “predetermined adhesiveness” indicated by the adhesive part is not particularly limited because it can be adjusted as appropriate according to the type of adherend. For example, an adhesive sheet is bonded to the adherend. In addition, it is preferable that after the adhesive part is cured by moisture absorption, the adhesive part has a degree of adhesion that allows the adhesive part and the adherend to be firmly bonded. Among them, when the adherend surface to which the adhesive sheet is bonded is a vertical surface or a normal surface, for example, when bonding to a tunnel wall or ceiling, the adhesive portion should exhibit high adhesiveness. Is preferred. Specifically, it is preferable that the adhesive portion has a predetermined punching strength, for example, the punching strength after curing of the adhesive portion is preferably 1.5 kN or more. Since the punching strength after curing of the adhesive portion is within the above range, the adhesive portion and the adherend can be firmly bonded, and for example, it is also suitably used for tunnel walls and ceilings. be able to.

  The punching strength after curing of the adhesive portion can be measured by the following method. First, a substrate defined in JIS A 5372 is prepared, and the core is cored in a shape of φ100 mm. Next, it can measure by arrange | positioning the adhesive-bonding part hardened | cured by moisture absorption in the center part of the said board | substrate, and performing a punching test according to JSCE-K511.

(3) Thickness The thickness of the adhesive portion is appropriately adjusted according to the type and purpose of the adherend to which the adhesive sheet is bonded, and is preferably 100 μm or more, for example. Moreover, it is preferable that the thickness of an adhesive bond part is 500 micrometers or less, and it is preferable that it is 300 micrometers or less especially. When the thickness of the adhesive portion is within the above range, sufficient adhesiveness to the adherend can be exhibited.

(4) Manufacturing method The manufacturing method of an adhesive bond part will not be specifically limited if it is a method which can obtain a desired adhesive bond part. As a method for producing an adhesive part, for example, a moisture curable resin composition for forming an adhesive part is dispersed in a solvent, and the solvent in which the moisture curable resin composition is dispersed is used for a separator described later. The method of apply | coating to the surface and making it dry is mentioned. Specifically, the method is as follows.

  First, a moisture curable resin composition is prepared by blending, stirring and dissolving the above-described materials contained in the adhesive part. Although the stirrer used for stirring is not specifically limited, A normal kneading disperser can be used. Specifically, a two-roll mill, a three-roll mill, a pebble mill, a tron mill, a high-speed impeller disperser, a high-speed stone mill, a high-speed impact mill, a disper, a high-speed mixer, a ribbon blender, a kneader, an intensive mixer, a tumbler, a blender, a disperser, A homogenizer, an ultrasonic disperser, or the like can be used.

  Next, the obtained moisture curable resin composition is disposed on the surface of the separator. Examples of the arrangement method of the moisture curable resin composition include a coating method and a printing method. Specific examples of the coating method include roll coating, reverse coating, comma coating, knife coating, die coating, and gravure coating. Specific examples of the printing method include a gravure printing method, a flexographic printing method, and an offset printing method.

  Thereafter, the moisture curable resin composition is dried. In the drying process of the moisture curable resin composition, the solvent contained in the moisture curable resin composition is sufficiently volatilized, and the curing of the adhesive portion is excessively promoted so that the adhesiveness of the adhesive portion does not decrease. It is preferable to carry out under the condition of a grade. As specific drying conditions, for example, drying at a temperature of 50 ° C. or higher and 100 ° C. or lower for 2 minutes or longer and 20 minutes or shorter is preferable.

2. Separator The adhesive sheet of the present disclosure may have a separator on at least one surface of the adhesive part. Specifically, in the present disclosure, the separator may be disposed only on one surface of the adhesive portion, or the separator may be disposed on both surfaces of the adhesive portion. When separators are arranged on both sides of the adhesive part, one separator is peeled off to expose the adhesive part, and the surface of the exposed adhesive part is bonded to the adherend. By doing so, an adhesive sheet can be used.

The separator is preferably a moisture-proof member. Here, the separator “having moisture resistance” means that the adhesive part is not exposed to moisture through the separator until the adhesive sheet of the present disclosure is bonded to the adherend. It is preferable to have moisture resistance to such an extent that it can be performed. Specifically, it is preferable that the separator has a predetermined water vapor permeability. As the predetermined water vapor permeability, for example, the water vapor permeability of the separator under a temperature of 40 ° C. and a humidity of 90% RH is preferably 1 g / m ² / day or less, and in particular, 0.1 g / m ² / day or less. Preferably there is. The water vapor permeability can be measured according to JIS K7129.

  In the present disclosure, the separator disposed on the surface of the adhesive portion is a member that is peeled from the adhesive portion. Therefore, it is preferable that a separator has peelability with respect to an adhesive bond part. In this indication, in order to give exfoliation property to a separator, easy exfoliation processing may be given to the side of a separator which contacts a sticky adhesion part. As an easy peeling process performed on the surface of a separator, the process of apply | coating an easy peeling agent to the surface of a separator is mentioned, for example. Examples of the easy release agent include water-soluble resins, hydrophilic resins, waxes, silicone resins, fluorine resins, aminoalkyd resins, melamine resins, polyester resins, acrylic resins, and the like. Examples of the method for applying the easy-release agent include roll coating, gravure coating, and spray coating.

  Furthermore, when the surface of the separator is subjected to an easy peeling treatment, the surface of the separator that has been subjected to the easy peeling treatment is easily improved in order to improve the adhesive strength of the surface of the separator that has been subjected to the easy peeling treatment. An adhesion treatment may be applied. Examples of the easy adhesion treatment applied to the separator include a treatment for improving the wettability of the easy-release agent. Specific examples include corona discharge treatment, plasma treatment, ozone treatment, flame treatment, primer treatment, pre-heat treatment, dust removal treatment, vapor deposition treatment, and alkali treatment.

  Specific separators in the present disclosure include, for example, an aluminum vapor-deposited film, a silica vapor-deposited film, an aluminum foil, a polyethylene film having a thickness of 0.1 mm or more, a film containing a moisture-proof filler, etc. .

  The separator in the present disclosure may have a predetermined light shielding property according to the type of material included in the adhesive portion and the environment in which the adhesive sheet of the present disclosure is used. When the separator has a predetermined light-shielding property, it is possible to suppress deterioration of the adhesive part due to incidence of ultraviolet rays or the like on the adhesive part. Examples of the separator having a predetermined light-shielding property include an aluminum foil separator, an aluminum vapor deposition film, a colored separator, and a film separator containing an ultraviolet absorber.

  The thickness of the separator is appropriately adjusted according to the dimensional stability, rigidity, flexibility and the like of the separator, and is preferably 5 μm or more and 200 μm or less, for example.

  As a manufacturing method of a separator, if it is a method which can obtain a desired peeling layer separator, it will not specifically limit. For example, a method using a solution casting method, a melt extrusion method, a calendar method, or the like can be given.

3. Others The adhesive sheet of the present disclosure may be a single sheet or a long sheet. When the adhesive sheet is long, the adhesive sheet can be wound into a roll to form an adhesive sheet roll. The adhesive sheet may be packed with a moisture-proof sheet. For example, a single-sided adhesive sheet in which separators are arranged on one or both surfaces of the adhesive part may be packed with a moisture-proof sheet, and an adhesive sheet roll is packed with a moisture-proof sheet. May be. When a single-wafer adhesive sheet is packed, usually, the adhesive sheet is provided with separators on both sides. When the adhesive sheet is packed with a moisture-proof sheet, it is preferable that moisture does not exist inside the package. Specifically, the inside of the package may be filled with dry air or dry nitrogen, and the inside of the package may be in a vacuum state with an internal vacuum degree of 5 Pa or less.

  The adhesive sheet of the present disclosure can be used by bonding the adhesive sheet to an adherend and curing the adhesive part. When the adhesive sheet has a configuration in which a separator is disposed on one surface of the adhesive part and is an adhesive sheet roll, a necessary amount is unwound from the adhesive sheet roll, The adhesive part can be bonded to the adherend by placing the exposed part on the surface of the adherend and then cutting it. In addition, in the case where the separator is disposed on both sides of the adhesive portion, and the adhesive sheet is a sheet, the sheet adhesive sheet is cut into a desired size and cut. After peeling off one separator of the adhesive sheet thus exposed to expose the adhesive part, the exposed surface of the adhesive part can be bonded to the surface of the adherend. Furthermore, when the adhesive sheet is packed with a moisture-proof sheet, after the moisture-proof sheet is opened and the adhesive sheet is taken out, one of the separators is peeled to expose the adhesive part, The exposed surface of the adhesive portion can be bonded to the surface of the adherend.

  When the adhesive sheet of the present disclosure is bonded to an adherend, it is preferable that air bubbles and dust do not enter between the adhesive portion and the adherend. Further, in the present disclosure, when the adhesive sheet is bonded to the adherend, it may be heat-pressed using an iron or the like, or may be pressed and bonded using a roller while gently vibrating. .

  The adhesive sheet of the present disclosure can reinforce the adherend by bonding the adherend to the adherend and then curing the adhesive section by moisture absorption. Here, curing of the adhesive part by moisture absorption means that the amine produced by the reaction of the curing agent and moisture reacts with the epoxy resin, and the adhesive part after curing has, for example, the following formula: It has the structure shown in (2). In addition, since detailed description about the reinforcement method using the adhesive sheet | seat of this indication is described in the term of the "B. reinforcement method" mentioned later, description here is abbreviate | omitted.

  The adhesive sheet of the present disclosure can be used by being bonded to an arbitrary adherend. The adhesive sheet of the present disclosure can use concrete or iron as an adherend in so-called infrastructure equipment such as roads, railways, water and sewage systems, harbor facilities, houses, and parks. Is suitable when it has a core material. Since the adherend will be described later in the section “5. Adherend”, description thereof is omitted here.

5). Adherent The adherend to which the adhesive sheet of the present disclosure is bonded is not particularly limited as long as it can bond the adhesive portion. For example, so-called infrastructure facilities such as roads, railways, water and sewage systems, port facilities, houses, and parks can be mentioned.

B. Reinforcing method The reinforcing method of the present disclosure is a reinforcing method for reinforcing an adherend using an adhesive sheet having an adhesive part that is cured by moisture absorption, the adhesive having the adhesive part. A step of preparing a sheet, a step of bonding the adhesive portion of the adhesive sheet to the surface of the adherend, and a surface bonded to the adherend of the adhesive portion; Has a step of curing the adhesive portion with the opposite surface exposed, and the adhesive portion has an epoxy resin, an acrylic resin, and a curing agent, and the curing agent is And a ketimine compound produced by a condensation reaction between an amine having a primary amino group and diethyl ketone.

  The reinforcing method of the present disclosure will be described with reference to the drawings. FIG. 3A to FIG. 3D are schematic process diagrams illustrating an example of the reinforcing method of the present disclosure. In the reinforcing method of the present disclosure, as shown in FIGS. 3A to 3D, the adhesive 2 that is cured by moisture absorption, and the separator 2 is disposed on at least one surface of the adhesive 1. This is a reinforcing method for reinforcing the adherend 3 using the adhesive sheet 10. Specifically, as shown in FIG. 3 (a), the step of preparing the adhesive sheet 10 provided with the adhesive part 1 and the adhesive part 1 as shown in FIG. 3 (b). After the step of bonding to the surface of the adherend 3 and the bonding step, as shown in FIG. 3 (c), it is opposite to the surface bonded to the adherend 3 of the adhesive portion 1 And a step of curing the adhesive portion 1 with the side surface exposed. Thereby, in this indication, as shown in Drawing 3 (d), it becomes possible to laminate adherence part 1 'hardened to adherend 3, and to strengthen adherend 3. In the adhesive sheet used in the present disclosure, the adhesive part includes an epoxy resin, an acrylic resin, and a curing agent, and the curing agent includes an amine having a primary amino group and diethyl ketone. It is a ketimine compound produced by a condensation reaction with. 3A to 3D are examples in which the adhesive sheet 10 in the present disclosure has the adhesive 2 and the separator 2 on one surface of the adhesive 1.

In the present disclosure, the adhesive sheet has a predetermined adhesive part. Thereby, it can be hardened by moisture absorption and an adherend can be reinforced using the adhesive sheet which has the outstanding sheet stability. Note that the detailed description can be the same as that described above, and thus the description thereof is omitted here.
Hereinafter, the reinforcing method of the present disclosure will be described.

1. Preparation Step The preparation step in the present disclosure is a step of preparing an adhesive sheet having an adhesive part. In addition, since the adhesive sheet used in the reinforcing method of the present disclosure can be the same as the contents described in the above-mentioned section “A. Adhesive sheet”, description thereof is omitted here.

2. Bonding step The bonding step in the present disclosure is a step of bonding the adhesive portion of the adhesive sheet to the surface of the adherend.

  The process is not particularly limited as long as the adhesive part can be bonded to the surface of the adherend. In this step, the entire surface of the adhesive portion may be bonded to the adherend, or only a part of the adhesive portion may be bonded to the adherend.

  In addition, about the specific method of bonding an adhesive bond part to a to-be-adhered body in this process, it can be made to be the same as that of the content described in the item of "A. Adhesive sheet 4. Others" mentioned above. Therefore, the description here is omitted.

3. Curing step The curing step in the present disclosure is performed by curing the adhesive portion in a state where the surface opposite to the surface bonded to the adherend of the adhesive portion is exposed after the bonding step described above. It is a process to make.

  In this step, the state of exposing the surface opposite to the surface bonded to the adherend of the adhesive portion is opposite to the surface bonded to the adherend of the adhesive portion. Indicates that the surface is in contact with the outside air, that is, has no separator. Therefore, after a bonding process, when it has a separator on the surface on the opposite side to the surface bonded by the adherend of the adhesive bond part, it is preferable to peel the said separator from an adhesive sheet. Examples of the method for peeling the separator include a method for peeling the separator from the adhesive sheet by a physical method.

  In this step, the adhesive part where the surface opposite to the surface bonded to the adherend is exposed is cured by moisture absorption. As a method of curing the adhesive portion by moisture absorption, for example, in an environment where moisture exists, there is a method of allowing the adhesive portion exposed to moisture to stand until it reacts with water and cures. Can be mentioned.

  Here, in the environment where moisture exists, the time until the adhesive part exposed to moisture reacts with water and hardens is called curing time of the adhesive part. The curing time of the adhesive part is appropriately adjusted according to the material of the adhesive part, that is, the composition and blending ratio of the moisture curable resin composition constituting the adhesive part, the environmental conditions such as humidity and temperature. be able to. The curing time for the adhesive portion in the present disclosure can be, for example, 6 hours or more and 7 days or less in a temperature 23 ° C. and humidity 50% environment. When the curing time of the adhesive portion is within the above range, the adhesive portion can be sufficiently cured by moisture absorption, and the adherend can be reinforced more effectively. In addition, about the physical property of the adhesive bond part after hardening, it describes in the above-mentioned "A. Adhesive sheet 1. Adhesive part (2) Physical property" and "A. Adhesive sheet 4. Others". Since it can be the same as that described, description here is omitted.

  In this indication, it is preferred that the punching strength of the adhesion part after a hardening process is 1.5 or more kN. In addition, about the punching strength after hardening of the adhesion part in this indication, it shall be the same as the content demonstrated by the term of the above-mentioned "A. Adhesive sheet 1. Adhesion part (2) Physical property." The description here is omitted.

4). Primer treatment step The reinforcing method of the present disclosure may have a primer treatment step of applying a primer to the surface of the adherend to which the adhesive bond portion is to be bonded before the bonding step. Moreover, the primer used by primer processing has an epoxy resin and a polyamine type hardening | curing agent.

  In the present disclosure, before the bonding step, the surface of the adherend to which the adhesive portion is bonded is provided with a primer treatment step for performing primer treatment, whereby the adhesion between the adhesive portion and the adherend is performed. The property can be further strengthened.

  Examples of the epoxy resin included in the primer include glycidyl ether type epoxy resin polyamine type curing agents such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenolvolak type epoxy resin; glycidyl ester type epoxy resin such as hexahydrophthal. Glycidyl ester, dimer acid glycidyl ester; glycidyl amine type epoxy resin, eg triglycidyl isocyanurate, tetraglycidyl diaminodiphenylmethane; linear aliphatic epoxy side, eg epoxidized polybutadiene, epoxidized soybean oil; alicyclic epoxy side For example, 3,4-epoxy-6-methylcyclohexyl methyl carboxylate, 3,4-epoxycyclohexyl methyl carboxylate and the like can be mentioned.

  The polyamine curing agent that the primer has is preferably liquid at room temperature. Examples thereof include aliphatic polyamines, alicyclic polyamines, aromatic polyamines, polyamide polyamines and polymercaptans.

  The primer may have other materials as needed in addition to the epoxy resin and the polyamine curing agent. Examples of other materials include general additives such as a diluent, a thixotropic agent, and a coupling agent.

  The primer treatment step can be usually carried out by applying a primer to the surface of the adherend and then drying it. Examples of the method for applying the primer to the surface of the adherend include a method using a brush or a roller. The thickness of the primer layer obtained by applying a primer in the primer treatment step can be, for example, in the range of 1 μm to 1 mm.

5). Other Steps In the present disclosure, in addition to the above-described bonding step, peeling step, and curing step, other steps may be included as necessary.

  As other steps, for example, as shown in FIG. 1B, when the separators 2a and 2b are provided on both surfaces of the adhesive portion 1, one separator 2a is peeled before the bonding step. You may have the peeling process to perform. That is, in this case, in the peeling step, one separator 2a is peeled off, and after the bonding step in which the exposed adhesive part is stuck to the adherend, the other separator 2b is peeled off and the curing step is performed. It will be. In addition, since it can be made to be the same as that of the peeling method of the separator demonstrated in the term of "3. hardening process" mentioned above, description here is abbreviate | omitted.

  The other steps can be appropriately selected according to the type of adherend to be reinforced in the present disclosure, and are not particularly limited. As other processes, for example, before the bonding process, with respect to the surface of the adherend to which the adhesive portion is bonded, a surface treatment process using a sander keren or a gold brush or the like, Examples include a flattening correction process for flattening. Moreover, the light-resistant agent application | coating process of apply | coating a light-proofing agent to the surface on the opposite side to the surface bonded to the to-be-adhered part of an adhesive bond part after a bonding process is mentioned. In addition, about the surface treatment process, the unevenness correction treatment process, and the light-proofing agent application process described above, since they can be the same as conventionally known processes, description thereof is omitted here.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  The present disclosure will be described in more detail with reference to the following examples.

[Example]
(Synthesis of ketimine)
142 g of 1,3-bisaminomethylcyclohexane (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name 1,3-BAC), 258 g of 3-fold molar equivalent of diethyl ketone, and 200 g of toluene are placed in a flask, and water formed is removed by azeotropic distillation. The reaction was continued for 20 hours at a temperature (120 to 150 ° C.) at which toluene and diethyl ketone were refluxed. Then, excess diethyl ketone and toluene were distilled off to obtain a ketimine compound.

(Preparation of adhesive sheet)
A transparent polyester film (trade name: SP-PET-03, film thickness: 38 μm, manufactured by Tosero Co., Ltd.) having a release treatment with a silicone release agent on one side was prepared as a separator. An applicator is prepared such that the adhesive-bonded portion forming composition containing the moisture-curable resin composition and the solvent is applied to the release-treated surface of the prepared separator that has been subjected to the release treatment so that the thickness after coating is 200 μm. It applied using. Finally, it was dried at 80 ° C. for 2 minutes using a drying oven to obtain an adhesive sheet having an adhesive part and a separator. The details of the moisture curable resin composition are shown in Table 1.

[Comparative Example 1]
An adhesive sheet was produced in the same manner as in Example except that the material of the adhesive part was changed.

[Comparative Example 2]
Instead of the adhesive sheet, an adhesive sheet (Structural Adhesive Tape VHB Tape manufactured by 3M Company) was used.

[Comparative Example 3]
An adhesive sheet was prepared in the same manner as in Example except that 216 g of methyl ethyl ketone was used as the carbonyl compound and ketimine was synthesized.

[Comparative Example 4]
An adhesive sheet was prepared in the same manner as in Example except that 300 g of methyl isobutyl ketone was used as the carbonyl compound and ketimine was synthesized.
Details are shown in Table 1.

  As shown in Table 1, “-” in the column of the acrylic resin of Comparative Example 1 means that it was not contained in the moisture curable resin composition. Moreover, since the comparative example 2 uses the commercially available adhesive tape, it shows as "-" in Table 1.

The details of the liquid epoxy resin, solid epoxy resin, and acrylic resin in Table 1 are as follows.
Liquid epoxy resin (bisphenol A type epoxy resin, epoxy equivalent: 190 g / eq., Molecular weight: 380, manufactured by Mitsubishi Chemical Corporation, trade name: jER828)
Solid epoxy resin (bisphenol A type epoxy resin, molecular weight: 5000, manufactured by Mitsubishi Chemical Corporation, trade name: jER1009)
Acrylic resin (modified methyl methacrylate-butyl acrylate-methyl methacrylate triblock copolymer having a polar group introduced, Tg: −42 ° C., manufactured by Arkema, Inc., trade name: M22N)

(Evaluation)
Examples and Comparative Examples 1 to 4 were evaluated. The evaluation method is as follows. First, a concrete test piece was prepared, and the coating amount after drying a primer (primary agent: bisphenol-based epoxy resin, curing agent: epoxy amine primer with knitted aliphatic polyamine, E810LW manufactured by Konishi Co., Ltd.) It apply | coated so that it might become 200 g / m < ² >, and it was made to dry. Next, the adhesive sheet is peeled off the separator on one side, and the exposed adhesive layer is bonded to the surface of the primer-treated concrete piece with a hand roll, at a temperature of 23 ° C. and a humidity of 50%. For 7 days. After curing, a punch test was performed according to JSCE-K511. The evaluation results are shown in Table 2.

  As shown in Table 2, in Examples, a desired adhesive sheet could be obtained, but in Comparative Example 1, the adhesive part became liquid and could not be formed into a sheet. This is considered due to the fact that the adhesive portion does not have an acrylic resin.

  Next, the punching strength after curing was measured. As a result, in the example, a higher punching strength was obtained than in Comparative Examples 1 and 2. From this, it was found that the adhesive sheet of the present disclosure has high adhesiveness of the adhesive part after curing. On the other hand, in Comparative Example 3 and Comparative Example 4, since the progress of curing of the adhesive portion was fast, it was not possible to bond to the adherend, and it was impossible to measure the punching strength. That is, in the example, it was found that excellent sheet stability was obtained, whereas in Comparative Example 3 and Comparative Example 4, desired sheet stability could not be obtained.

DESCRIPTION OF SYMBOLS 1 ... Adhesive part 1 '... Adhesive part after hardening 2 ... Separator 3 ... Adhering body 4 ... Core material 10 ... Adhesive sheet

Claims (5)

An adhesive sheet having an adhesive part that is cured by moisture absorption,
The adhesive portion has an epoxy resin, an acrylic resin, and a curing agent,
The adhesive is characterized in that the curing agent is a ketimine compound produced by a condensation reaction between an amine having a primary amino group and diethyl ketone.   The adhesive sheet according to claim 1, wherein the adhesive part has a core material. A reinforcing method for reinforcing an adherend using an adhesive sheet having an adhesive part that is cured by moisture absorption,
A preparation step of preparing the adhesive sheet having the adhesive part;
A bonding step of bonding the adhesive portion of the adhesive sheet to the surface of the adherend;
In the state where the surface opposite to the surface bonded to the adherend of the adhesive portion is exposed, the curing step of curing the adhesive portion, and
The adhesive portion has an epoxy resin, an acrylic resin, and a curing agent,
The said hardening | curing agent is a ketimine compound produced | generated by the condensation reaction of the amine which has a primary amino group, and diethyl ketone, The reinforcement method characterized by the above-mentioned. Before the bonding step, the surface of the adherend for bonding the adhesive portion has a primer treatment step for applying a primer,
The reinforcing method according to claim 3, wherein the primer includes an epoxy resin and a polyamine-based curing agent.   The reinforcing method according to claim 3 or 4, wherein a punching strength of the adhesive portion after the curing step is 1.5 kN or more.

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