JP2005029722A - Method for bonding silicone rubber to adherend and adhesive for silicone rubber therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for bonding a silicone rubber to an adherend in a good state and an adhesive for silicone rubber for the above bonding method. <P>SOLUTION: The method for the bonding of a silicone rubber and an adherend comprises a step to modify the surface of the silicone rubber, a step to form a primer layer by coating at least a part of the surface-modified silicone rubber with an epoxy resin composition and curing the applied epoxy resin composition, a step to coat at least a part of the primer layer with a photosetting acrylic resin composition, and a step to form an adhesive layer between the primer layer and the adherend by placing the adherend on the photosetting acrylic resin composition and curing the photosetting acrylic resin composition. The adhesive for silicone rubber contains the epoxy resin composition and the photosetting acrylic resin composition. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for bonding silicone rubber and a member to be bonded, and an adhesive for silicone rubber used therefor.

  Conventionally, buttons such as mobile phones, personal digital assistants, remote controls for various home appliances, card remote controllers and various keyboards are made of soft or hard resin on a keypad made of silicone rubber having excellent weather resistance and electrical insulation. The key top made of is formed by bonding.

  In the first place, silicone rubber has poor adhesion to other materials and is easy to peel off, so that there is a problem that the key top is detached during use. In particular, recently, there are many cases in which an operation of pressing the same button many times is required, and the demand for improving the adhesiveness has become stronger.

  In order to solve this problem, Japanese Patent Application Laid-Open No. 11-144549 discloses a method of bonding a key top to a key top using a short-time moisture curable reaction curable resin such as cyanoacrylate as an adhesive after surface modification of the silicone rubber. It is described in the gazette (patent document 1). However, its adhesiveness has not been sufficient yet. In addition, since a short-time moisture-curable reaction curable resin is used, there is a problem that application by screen printing is impossible and productivity is low. Further, cyanoacrylate has a problem of whitening the adherend.

In addition, there is a method of preventing the detachment by forming a brim or the like on the key top, but even in this case, when the key pad and the key top are separated, the key top becomes unstable, There was a problem that the operability deteriorated.
JP-A-11-144549

  This invention is made | formed in view of the said situation, and it aims at providing the adhesive method which can adhere | attach silicone rubber and a to-be-adhered member favorably, and the adhesive agent for silicone rubber used therefor.

The present invention
(A) a step of surface-modifying the surface of the silicone rubber;
(B) An epoxy resin composition is applied to at least a part of the surface-modified silicone rubber, and the epoxy resin composition is cured, so that the epoxy is applied to at least a part of the silicone rubber. Forming a primer layer in which the resin composition is cured;
(C) applying a photocurable acrylic resin composition to at least a part of the primer layer;
(D) A member to be adhered is disposed on the photocurable acrylic resin composition, and the photocurable acrylic resin composition is cured, so that the light is interposed between the primer layer and the member to be adhered. Forming a cured adhesive layer of the curable acrylic resin composition;
It is the adhesion method of the silicone rubber which has this, and the member to be adhered.

  According to such a bonding method of the present invention, the silicone rubber and the member to be bonded can be favorably bonded.

The present invention also provides:
An adhesive for silicone rubber for bonding silicone rubber and an adherend,
(A) an epoxy resin composition for forming a primer layer on at least a part of the silicone rubber;
(B) a photocurable acrylic resin composition for forming an adhesive layer between the primer layer and the adherend,
This is an adhesive for silicone rubber having two components.

  Such an adhesive for silicone rubber of the present invention becomes an adhesive for silicone rubber capable of favorably bonding the silicone rubber and the member to be bonded by the above-described bonding method.

  Using a silicone rubber adhesive having two components of an epoxy resin composition and a photocurable acrylic resin composition, a step of surface modifying the surface of the silicone rubber, and at least on the surface-modified silicone rubber Applying an epoxy resin composition to a part and curing the epoxy resin composition to form a primer layer in which the epoxy resin composition is cured on at least a part of the silicone rubber; and on the primer layer A step of applying a photocurable acrylic resin composition to at least a part, a member to be bonded on the photocurable acrylic resin composition, and a curing treatment of the photocurable acrylic resin composition, A step of forming an adhesive layer in which the photocurable acrylic resin composition is cured between the adhesive member and the adherend member. With, it is possible to satisfactorily adhere the silicone rubber and the bonded component.

  The present invention relates to adhesion between silicone rubber and a member to be bonded. Silicone rubber generally has poor adhesion and is easily peeled off, but according to the bonding method of the present invention, it is possible to bond the silicone rubber and the member to be bonded satisfactorily.

  The silicone rubber in the present invention is not particularly limited, and a silicone rubber molded into a desired size and shape using millable silicone rubber or liquid silicone rubber can be used. The thickness is usually about 0.1 mm to 10 mm. Examples of the millable silicone rubber include SH831U, SH841U, SH851U, SH961U, SE4705U, SE4706U (above, trade names) manufactured by Toray Dow Corning Silicone, KE931-U, KE941-U, KE951-U manufactured by Shin-Etsu Silicone. , KE961-U, KE971-U, KE981-U (above, product names), TSE221-4U, TSE221-5U, TSE2121-6U, XE20-523-5U, XE20-523-6U (above, products) manufactured by Toshiba Silicone Name). Examples of the liquid silicone rubber include SE6745A / B (trade name) manufactured by Toray Dow Corning Silicone, KE1990 (A / B) (trade name) manufactured by Shin-Etsu Silicone, TSE3503, TSE3504, TSE350, and TSE3502 manufactured by Toshiba Silicone. (Product name).

  The member to be bonded in the present invention is not particularly limited, and polyethylene, polypropylene, polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, polycarbonate, polyoxymethylene, polyethylene terephthalate, polyethylene naphthalate, polytetrafluoroethylene, polyamide, polyimide, ABS Resin, AS resin, acrylic resin, epoxy resin, unsaturated polyester resin, resin such as phenol resin, metal such as copper, iron, aluminum, ceramics such as metal oxide, metal nitride, metal fluoride, etc. It can be. This is preferably carried out when a resin having low adhesion to silicone rubber is used as the member to be bonded. Among these, it is more preferable when any one of polycarbonate, ABS resin, and acrylic resin is used as the adherend. This is particularly preferred when polycarbonate is used as the adherend.

  In the bonding method of the present invention, first, (A) a step of surface-modifying the surface of the silicone rubber is performed. By the surface modification treatment in this step, the surface of the silicone rubber is easily adhered, and the adhesive strength with the adherend can be increased.

  Specifically, as the surface modification treatment, (i) irradiation treatment with ultraviolet rays of a short wavelength from a mercury lamp, (ii) corona discharge treatment by discharge in which breakdown is caused by applying a high voltage between the electrodes in the atmosphere, ( iii) Flame treatment through strong oxidation flame, (iv) Plasma treatment by glow discharge in low-pressure inert gas, oxygen, halogen gas, etc. (v) Cups made of silane, titanium, aluminum, etc. The process etc. which apply | coat a ring agent on the surface are mentioned. Both have the effect of increasing the surface energy of the silicone rubber, and can increase the adhesive strength with other materials. In particular, a corona discharge treatment is preferable from the viewpoint of increasing the adhesive strength with a simple treatment. Further, these surface modification treatments may be performed alone or in combination with a plurality of surface modification treatments.

  In the bonding method of the present invention, after the step (A), (B) applying an epoxy resin composition to at least a part of the surface-modified silicone rubber, and curing the epoxy resin composition. The step of forming a primer layer in which the epoxy resin composition is cured is performed on at least a part of the silicone rubber. By this step, it is possible to increase the adhesive strength with the member to be bonded by the acrylic resin composition described later.

  The epoxy resin composition of the present invention is not particularly limited, and is a combination of an epoxy resin, a curing agent, and, if necessary, a solvent and various additives.

  Epoxy resins include bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether, resorcinol diglycidyl ether, hexahydrobisphenol A diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, neopentyl Glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, phenol novolac type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, tetrabromobisphenol A Diglycidyl ether, bisphenol hex Glycidyl ether type epoxy resins such as fluoroacetone diglycidyl ether, tetraphenyl glycidyl ether ethane, and triphenyl glycidyl ether methane; diglycidyl ester types such as phthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ether, and dimer acid diglycidyl ester Epoxy resins; glycidylamine type epoxy resins such as triglycidyl isocyanurate, tetraglycidyldiaminodiphenylmethane, tetraglycidylmetaxylenediamine; 3,4-epoxycyclohexylmethylcarboxylate, 3,4-epoxy-6-methylcyclohexylmethylcarboxylate, etc. The alicyclic epoxy resin or the like can be used, and may be appropriately selected and used according to the application. Epoxy resins may be used alone or in combination of two or more. From the viewpoint of handleability, it is preferable to include an alicyclic epoxy resin.

Curing agents include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, diethylaminopropylamine, polyamidoamine, mensendiamine, isophoronediamine, N-aminoethylpiperazine, bis (4-amino-3-methylcyclohexyl) methane, bis Polyamine type curing agents such as (4-aminocyclohexyl) methane, metaxylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, metaphenylenediamine, dicyandiamide, adipic dihydrazide; phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyl Tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyl nadic anhydride, dodecyl succinic anhydride, chlorendic anhydride, pyro anhydride Acid anhydride type curing agents such as litnic acid, benzophenone tetracarboxylic acid anhydride, ethylene glycol bis (anhydrotrimate), methylcyclohexene tetracarboxylic acid anhydride, trimellitic anhydride; polyphenol types such as phenol novolac and cresol novolak Curing agent: Polymercaptan type curing agent such as trioxane trimethylene mercaptan, polysulfide; benzyldimethylamine, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (diaminomethyl) phenol, 2-methylimidazole, 2- Ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazo Anionic polymerization type curing agent such as _{Le; BF 3, PF 5, AsF} 5, SbF 5, SnCl 5, FeCl 3, or, of these, amine salts, aromatic diazonium salts, triaryl sulfonium salts or triallyl selenium salt The cationic polymerization type curing agent can be used, and may be appropriately selected according to the use. One curing agent may be used, or two or more curing agents may be combined. From the viewpoint of handleability, it is preferable to include a cationic polymerization type curing agent. What is necessary is just to select suitably from the composition of each component of an epoxy resin composition, and to determine about the compounding ratio of an epoxy resin and a hardening | curing agent.

  It does not specifically limit as a solvent contained as needed in an epoxy resin composition, A well-known solvent can be used. For example, xylene, toluene, ethyl acetate, isobutyl acetate, methanol, ethanol, isopropyl alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, etc. Can be mentioned.

  Various additives included in the epoxy resin composition as necessary are not particularly limited, and known additives can be used. For example, a diluent, a plasticizer, a coupling agent, a filler, etc. are mentioned. From the viewpoint of enhancing adhesiveness, it is preferable that a coupling agent is included. The coupling agent is not particularly limited and may be appropriately selected from silane-based, titanium-based, aluminum-based, etc., and silane-based coupling agents are particularly preferable.

  Such an epoxy resin composition is applied to at least a part of the above-described surface-modified silicone rubber and then cured to form a primer layer. The method for applying the epoxy resin composition is not particularly limited, and examples thereof include brushing, roller coating, dipping, potting, spin coating, screen printing, and dispensing. From the viewpoint of workability, any one of the brush coating method, the roller coating method, and the dipping method is preferable. In particular, the brushing method is preferable. The curing method may be determined by appropriately selecting from the composition of each component of the epoxy resin composition. For example, a method of leaving at room temperature (room temperature curing), a method of heating (heat curing), a method by light irradiation (photocuring) and the like can be mentioned. From the viewpoint of workability, heat curing or photocuring is preferable. When the epoxy resin composition contains a solvent, it is preferable to remove the solvent by a drying treatment or the like before curing. Although there is no restriction | limiting in particular in the thickness of a primer layer, In order to respond | correspond to a small apparatus, the thinner one is good and about 0.1-10 micrometers is preferable.

  In the bonding method of the present invention, after the step (B), (C) a step of applying a photocurable acrylic resin composition on at least a part of the primer layer, and (D) a photocurable acrylic resin composition. A step of forming an adhesive layer in which the photocurable acrylic resin composition is cured between the primer layer and the adherend member by disposing the adherend member thereon and curing the photocurable acrylic resin composition; ,I do. Through these steps, the silicone rubber and the adherend can be favorably bonded via the primer layer.

  The photocurable acrylic resin composition includes (meth) acrylate monomers or oligomers, photopolymerization initiators, and other reactive diluents, solvents, sensitizers, pigments, fillers, paints, Includes foaming agents. In addition, the expression “(meth) acrylate” means methacrylate or acrylate (the same applies hereinafter).

  (Meth) acrylate monomers or oligomers include monofunctional (meth) acrylate monomers, polyfunctional (meth) acrylate monomers, polyether (meth) acrylates, polyester (meth) acrylates, polyurethane (meth) acrylates, polyether polyurethanes ( Select a known one such as (meth) acrylate, polyester polyurethane (meth) acrylate, epoxy (meth) acrylate, melamine (meth) acrylate, amino resin (meth) acrylate, acrylic resin (meth) acrylate, or a modified product thereof. Can be used. These may be one kind or a combination of two or more. When (meth) acrylate-based oligomers are used, since these have high viscosity, the viscosity is usually adjusted with a reactive diluent or solvent.

  Examples of the photopolymerization initiator include 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzophenone, 1- [4- (2-hydroxyethoxy) phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropane -1-one, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, acylphosphine oxide, etc. Any known one can be appropriately selected and used. These may be one kind or a combination of two or more.

  The photocurable acrylic resin composition containing the above components may have ultraviolet curable properties or visible light curable properties. In particular, a photocurable acrylic resin composition having visible light curability is preferable because visible light is easily transmitted when polycarbonate, acrylic resin, or ABS resin is used as an adherend. In addition, since it hardens | cures after arrange | positioning a to-be-adhered member, when the heat resistance of a to-be-adhered member is low, the thermosetting acrylic resin composition which is difficult to utilize is not so preferable.

  Examples of commercially available photocurable acrylic resin compositions having ultraviolet curable properties include 349, 350, 352, 366, 3523, LID-1316 (above, trade names) manufactured by Henkel Japan. Examples of commercially available photocurable acrylic resin compositions having visible light curability include 3201, 3221, 3301, 3311, 3321, 3341, 3102, 3103, 3104, 3105, 3106 (and above, trade names). .

  The application method of the photocurable acrylic resin composition in the present invention is not particularly limited, and examples thereof include a brush coating method, a roller coating method, a dipping method, a potting method, a spin coating method, a screen printing method, and a dispensing method. It is done. From the viewpoint of efficiently applying to a precise place, a screen printing method or a dispensing method is preferable. In particular, the screen printing method is preferable from the viewpoint of productivity. Although there is no restriction | limiting in particular in thickness, From a viewpoint of expressing high adhesiveness, about 1-200 micrometers is preferable.

  After applying such a photocurable acrylic resin composition to at least a part of the primer layer, placing the adherend, and irradiating the photocurable acrylic resin composition with predetermined light and curing, An adhesive layer is formed between the primer layer and the adherend member. What is necessary is just to select and determine the wavelength and intensity | strength of the light to irradiate suitably according to the photocuring characteristic of the photocurable acrylic resin composition to be used. In particular, it is preferable to cure with visible light because it is easy to transmit when polycarbonate or acrylic resin is used as the adherend. The temperature at the time of irradiation with light is often normal temperature (about 20 ° C.), but it can also be performed while heating within a range where the bonded member does not deform or the like.

  The adhesive for silicone rubber of the present invention comprises (a) an epoxy resin composition for forming a primer layer on at least a part on the silicone rubber, and (b) at least on the primer layer as described above. It has two components: a photocurable acrylic resin composition for forming an adhesive layer between a part and an adherend member. By setting it as such a structure, a silicone rubber and a to-be-adhered member can be adhere | attached firmly. Since the silicone rubber and the member to be bonded are bonded by the method of bonding the silicone rubber of the present invention and the member to be bonded as described above, the epoxy resin composition as the component (a) and the component (b) described above It is a preferred embodiment that the photocurable acrylic resin composition as a component is provided in an unmixed state. Each of the component (a) and the component (b) may be one liquid or may be provided in two or more liquids.

  As described above, the method for bonding the silicone rubber and the member to be bonded using the adhesive for silicone rubber of the present invention includes keypads for buttons of mobile phones, portable information terminals, remote controls for various household appliances, card remote controllers, and various keyboards. This is suitable for bonding the silicone rubber to the soft resin or hard resin which is the key top of the button.

  Hereinafter, the present invention will be described in detail by way of examples. In addition, the epoxy resin composition used in the Example is shown in Table 1, and the photocurable acrylic resin composition is shown in Table 2.

^* a-3 was used as a 5 mass% acetone solution.
The numbers in Table 1 represent parts by mass, and the abbreviations represent the following.
・ Uvacure UVR6128 (Dow Chemical Co., trade name)
Cycloaliphatic epoxy resin Sumifen TM (trade name, manufactured by Sumitomo Bayer Urethane Co., Ltd.)
Polyether polyol Epicote 152 (trade name, manufactured by Japan Epoxy Resin Co., Ltd.)
Phenol novolac epoxy resin / Cyracure UVI 6974 (trade name, manufactured by Union Carbide)
Triallylsulfonium hexafluoroantimony / Cyracure UVI6990 (trade name, manufactured by Union Carbide)
Triallylsulfonium hexafluorophosphate sun aid SI160L (trade name, manufactured by Sanshin Chemical Co., Ltd.)
Organosulfonium hexafluoroantimony.

Numbers represent parts by mass, and abbreviations represent the following.
・ 3341 (Henkel Japan, product name)
Visible light curable acrylic adhesive, CN966J75 (trade name, manufactured by Sartomer)
Polyester polyurethane acrylate / BR582E (Boomer Specialty, trade name)
Polyether Polyurethane Acrylate / BR543 (trade name, manufactured by Boomer Specialty)
Polyether polyurethane acrylate Aerosil # 200 (Nippon Aerosil Co., Ltd., trade name)
Ultrafine silica lucillin TPO (trade name, manufactured by BASF)
Acylphosphine oxide Irgacure 184 (trade name, manufactured by Ciba Specialty Chemicals)
1-Hydroxycyclohexyl phenyl ketone BYK070 (product name)
Silicone defoamer.

(Example 1)
The surface of a 15 mm × 25 mm × 3 mm thick silicone rubber (trade name: KE931-U, manufactured by Shin-Etsu Silicone) was subjected to corona discharge treatment using TANTEC High Frequency Generator HV05-2 (trade name). Specifically, the silicone rubber was conveyed on a conveyor at a rate of, for example, about 30 to 500 cm / min, and subjected to a corona discharge treatment using, for example, a rod-shaped electrode under conditions of 100 to 280 W in the atmosphere.

The epoxy resin composition a-1 was applied to the surface of this corona discharge-treated silicone rubber by a brush coating method so that the thickness after curing was 10 μm or less. The epoxy resin composition a-1 was cured by irradiating visible light with an intensity of 100 mW / cm ² for 30 seconds to form a primer layer.

Next, the photocurable acrylic resin composition b-1 is applied to the region of the central portion (15 mm × 15 mm) on the primer layer by a screen printing method so that the thickness after curing is 5 to 50 μm. Then, a polycarbonate resin plate (15 mm × 25 mm × thickness 3 mm) was placed thereon so as to form a cross shape with the silicone rubber. Then, the adhesive layer which the photocurable acrylic resin composition b-1 hardened | cured was formed by irradiating visible light with the intensity | strength of 100 mW / cm < ² > for 30 second, and the test piece was obtained.

On the silicone rubber side of the obtained test piece, via prism primer 770 (surface pretreatment agent, product name, manufactured by Henkel Japan) / prism 401 (cyanoacrylate adhesive, product name, manufactured by Henkel Japan), In order to reinforce the silicone rubber, it was attached to a glass epoxy laminate (model number: ES3230, manufactured by Risho Kogyo Co., Ltd., trade name), and a tensile test (Autograph AGS-100A (trade name) manufactured by Shimadzu Corporation) was used. Condition: 10 mm / min., room temperature), the adhesive strength was measured, and the adhesive strength was 1.91 N / mm ² . The results are summarized in Table 3.

(Example 2)
A test piece was prepared in the same manner as in Example 1 except that the adhesive layer was formed using the photocurable acrylic resin composition b-2. Evaluation of adhesive strength was attempted by the same method as in Example 1. Before breaking between the silicone rubber and the polycarbonate resin plate, the silicone rubber and the glass epoxy laminate were broken, and the adhesive force was good. The results are summarized in Table 3.

(Example 3)
A test piece was prepared in the same manner as in Example 1 except that the primer layer was formed using the epoxy resin composition a-2. When the adhesive strength was evaluated by the same method as in Example 1, the adhesive strength was 1.67 N / mm ² and good. The results are summarized in Table 3.

(Example 4)
Example 1 except that the epoxy resin composition a-3 was cured at 150 ° C. for 30 minutes to form a primer layer and the photocurable acrylic resin composition b-3 was used to form an adhesive layer. A test piece was prepared by the method. When the adhesive strength was evaluated by the same method as in Example 1, the adhesive strength was 1.69 N / mm ² and good. The results are summarized in Table 3.

(Example 5)
A test piece was prepared in the same manner as in Example 1 except that the primer layer was formed by curing the epoxy resin composition a-4 at 150 ° C. for 30 minutes. Evaluation of adhesive strength was attempted by the same method as in Example 1. Before breaking between the silicone rubber and the polycarbonate resin plate, the silicone rubber and the glass epoxy laminate were broken, and the adhesive force was good. The results are summarized in Table 3.

(Comparative Example 1)
A test piece was prepared in the same manner as in Example 1 except that no primer layer was formed. When the adhesive strength was evaluated by the same method as in Example 1, the adhesive strength was as low as 0.26 N / mm ² . The results are summarized in Table 3.

(Comparative Example 2)
In the same manner as in Example 1, the silicone rubber was subjected to corona discharge treatment, and the epoxy resin composition a-1 was further applied to the surface by brushing so that the thickness after curing was 10 μm or less. Applied. A polycarbonate resin plate (15 mm × 25 mm × thickness 3 mm) was placed thereon so as to form a cross with the silicone rubber. Thereafter, the epoxy resin composition a-1 was cured by irradiation with visible light at an intensity of 100 mW / cm ² for 30 seconds, but the silicone rubber and the polycarbonate resin plate were not bonded.

(Comparative Example 3)
A primer layer is formed using prism primer 770 (surface pretreatment agent, product name, manufactured by Henkel Japan), and an adhesive layer is formed using prism 401 (cyanoacrylate adhesive, product name, manufactured by Henkel Japan). A test piece was prepared in the same manner as in Example 1 except that. The prism primer 770 was not cured, and was allowed to stand at room temperature for 2 hours in order to volatilize the solvent. Also, since the prism 401 is a room temperature fast curing type, a polycarbonate resin plate was placed, and a sample that had passed 2 to 3 seconds was directly used as a test piece. When the adhesive strength was evaluated by the same method as in Example 1, the adhesive strength was low at 1.35 N / mm ² . The results are summarized in Table 3.

Claims (8)

(A) a step of surface-modifying the surface of the silicone rubber;
(B) An epoxy resin composition is applied to at least a part of the surface-modified silicone rubber, and the epoxy resin composition is cured, so that the epoxy is applied to at least a part of the silicone rubber. Forming a primer layer in which the resin composition is cured;
(C) applying a photocurable acrylic resin composition to at least a part of the primer layer;
(D) A member to be adhered is disposed on the photocurable acrylic resin composition, and the photocurable acrylic resin composition is cured, so that the light is interposed between the primer layer and the member to be adhered. Forming a cured adhesive layer of the curable acrylic resin composition;
A method for adhering a silicone rubber having an adhesive and an adherend.   The bonding method according to claim 1, wherein the member to be bonded is one of polycarbonate, acrylic resin, and ABS resin.   The adhesion method according to claim 1 or 2, wherein the surface modification treatment in the step (A) is a corona discharge treatment.   The adhesion method according to any one of claims 1 to 3, wherein the photocurable acrylic resin composition is applied in the step (C) by a screen printing method or a dispensing method.   The said photocurable acrylic resin composition has visible light sclerosis | hardenability, and the hardening process of the said photocurable acrylic resin composition in the said process (D) is performed by visible light irradiation. The adhesion method according to crab. An adhesive for silicone rubber for bonding silicone rubber and an adherend,
(A) an epoxy resin composition for forming a primer layer on at least a part of the silicone rubber;
(B) a photocurable acrylic resin composition for forming an adhesive layer between at least a part of the primer layer and the adherend member;
An adhesive for silicone rubber having two components.   The adhesive according to claim 6, wherein the epoxy resin composition contains a cationic polymerization type curing agent.   The adhesive according to claim 7 or 8, wherein the photocurable acrylic resin composition has visible light curability.