JP4522453B2 - Manufacturing method of rubber film composite - Google Patents

Description

  The present invention relates to a method for producing a rubber film composite, more specifically, a laminate of a rubber film and a base film, excellent interfacial adhesion between the rubber film and the base film, and the surface roughness of the rubber film. A method for producing an arbitrarily settable rubber film composite is provided.

  Since rubber films have cushioning properties, they are used as sealing materials and cushion materials in a wide range of industrial fields. However, rubber films, particularly silicone rubber films and ethylene propylene-based rubber films, have poor adhesiveness to other materials, and therefore require expensive adhesives when incorporating rubber films into devices and parts. In addition, since the rubber film is flexible, it has a defect such as inferior workability during assembling work. As a means to solve such problems, it is combined with a base film such as a polyester film that is excellent in heat resistance like a rubber film, has better adhesiveness than a rubber film, and can be bonded with a low-cost general-purpose adhesive. This method is known to be used, and since the rubber film is reinforced with the base film, the workability during the assembly work is improved, but it is put to practical use because the adhesion between the rubber film and the base film is poor. Not.

  As means for improving the adhesion between rubber, for example, silicone rubber and other materials, allyl glycidyl ether and glycidyl acrylate are blended with silicone rubber (see Patent Document 1), hexavinyldisiloxane, dimethyltetravinyldisiloxane, etc. (See Patent Document 2), compounding an alkenyl carbonate group-containing compound and / or a mercaptoacetate group-containing compound (see Patent Document 3), etc. are proposed. Even when a film made of rubber or ethylene propylene rubber is laminated on a polyester film, the interfacial adhesive force between the two films is still insufficient, and a practical composite has not been obtained.

  On the other hand, the rubber film composite may have various surface roughnesses depending on the purpose of use. For example, in a rubber sheet for cushioning to be mounted on a drive table of a compact disc, it is necessary to set the surface roughness appropriately in order to balance the grip properties and the detachability of the compact disc. As a method for controlling the surface roughness of the rubber film composite for such a purpose, various synthetic resin films and fabrics having different surface roughnesses are used as a cover sheet, and the surface of the cover sheet is superposed on an uncrosslinked rubber film surface. A method of transferring the form to a rubber film is known. For example, as a means for imparting fine irregularities to the surface of a general rubber sheet, a fabric weight that uses a mat or embossed polyethylene film or vinyl chloride film, or a filament fabric such as nylon taffeta or polyester taffeta for the cover sheet Is widely practiced.

By the way, the above-mentioned cover sheet is superimposed on the surface of the rubber film when it is not cross-linked, and peeled off after cross-linking, but as described above, the adhesive strength improver that improves the interfacial adhesive force with the base film. When the cover sheet is blended, even if an attempt is made to peel the cover sheet after cross-linking, the interfacial adhesion between the rubber film and the cover sheet is also improved, making it difficult to peel off the cover sheet. When the sheet was peeled off, there was a problem that the rubber film adhered to the cover sheet.
Japanese Patent Laid-Open No. 54-162751 Japanese Patent Laid-Open No. 3-111142 JP-A-8-120177

  This invention consists of a laminate of an arbitrary rubber film and an arbitrary base film, has excellent interfacial adhesive force, and can be bonded with an inexpensive general-purpose adhesive when incorporated into various devices and parts. A method for producing a rubber film composite that has good workability during assembling work and can set the surface roughness of the rubber film to any roughness such as a glossy surface or a satin finish. It is to provide.

The present invention relates to a laminate of a base film, a non-crosslinked rubber film comprising a rubber composition obtained by blending at least one compound selected from an acrylic acid derivative and a methacrylic acid derivative as an adhesion improver, and a cover sheet. In a method for producing a rubber film composite comprising a base film and a rubber film by performing a crosslinking treatment by irradiation with radiation, and then peeling off the cover sheet.
The laminate is (1) a laminate in which an interlayer adhesive force between the base film and the rubber film is weaker than an interlayer adhesive force between the rubber film and the cover sheet, or (2) the laminate The body is a laminate in which an uncrosslinked rubber film is formed on the cover sheet surface by a coating method, and then a base film is pasted on the uncrosslinked rubber film, and the solvent resistance in the base film coating method Is a laminate inferior to the solvent resistance of the cover sheet,
By performing the electron beam irradiation at least once from the base film side, the total energy of the electron beam applied to the interface between the base film and the rubber film of the electron beam irradiation performed before peeling the cover sheet is determined. A method for producing a rubber film composite characterized in that the total energy of an electron beam applied to the interface of the film is made larger.

  According to this invention, it is possible to obtain a rubber film composite comprising an arbitrary base film and an arbitrary rubber film, and the surface of the rubber film being controlled to an arbitrary roughness according to market demands. When the cover sheet is peeled off, it is easy to peel off and no rubber adheres to the cover sheet. And since the obtained rubber film composite is a composite of a rubber film and a base film, when the base film surface is incorporated into an apparatus or a part as an adhesive surface, the rubber film alone cannot be used due to its weak adhesive strength. Such a general-purpose adhesive can be used, and since it is stronger than the rubber film alone, the assembling work is facilitated and the efficiency is improved. Furthermore, since the above rubber film composite has a strong interlayer adhesion between the rubber film and the base film, it is not peeled off by external force after being incorporated into a device or a part, so that it can be used as a sealing material or cushioning material in a wide range of industrial fields. Can be used as

  In this invention, a rubber film made of a rubber composition containing an adhesion improver is used, and since this rubber film is laminated on the base film, the interlayer adhesion between the base film and the rubber film is enhanced, It is not easily peeled off from the interface, so the workability when incorporating into various devices is improved compared to the rubber film alone, and the surface of the base film is adhered when fixed to the above devices by bonding. By using it on the surface, bonding with a general-purpose adhesive becomes possible. And the electron beam irradiation conditions are specified, the interlayer adhesive force between a rubber film and a cover sheet is restrained low, and peeling of a cover sheet becomes easy.

  The base film in the present invention is not particularly limited as long as it is a film having good adhesion as compared with a rubber film and having a firmness, and is not collapsed by electron beam irradiation. Examples thereof include a polyolefin film, a polyester film, a polyamide film, a polysulfide film, a polyimide film, a polyether ether ketone film, a polysulfone film, a polyhalogenated vinyl film, and a polyhalogenated vinylidene film.

  As the base film, an easily adhesive polyester film whose surface is treated with actinic radiation or a compound that improves adhesiveness is laminated on the surface can be used. In this case, adhesion in the rubber film is possible. The compounding quantity of a property improvement agent can be decreased. Examples of the treatment method using active rays include corona discharge treatment, ultraviolet irradiation treatment, plasma treatment, flame treatment and the like, and the easy-adhesion component of the easy-adhesion film includes polyester-based, polyurethane-based, and polyacrylic compounds. Or a combination thereof. Further, the method of laminating the easy-adhesion layer may be either a so-called in-line method for laminating at the time of film formation or a so-called offline method for laminating on the film formed. And although the easy-bonding layer surface of the film which laminated | stacked the easy-bonding layer can be further processed with said active ray, it is not limited to these.

  The rubber components used in this invention include natural rubber (NR), silicone rubber (Q), ethylene propylene diene rubber (EPDM), acrylonitrile butadiene rubber (NBR), chloroprene rubber (CR), acrylic rubber (ACM) and fluorine. Any rubber such as rubber (FKM) and mixtures thereof can be used.

  The adhesion improver compounded in the rubber component is not particularly limited as long as it improves the adhesion of the rubber composition to the base film, but a compound containing a functional group active against radical reaction is preferable. . Examples of this compound include acrylic acid derivatives and methacrylic acid derivatives. Among these derivatives, compounds having 2 or more, particularly 3 or more unsaturated bonds are preferred. These compounds are compounds widely used as rubber co-crosslinking agents, and examples thereof include acrylic acid esters and methacrylic acid esters of polyhydric alcohols.

  The polyhydric alcohol acrylic ester or methacrylic ester is an ester compound obtained by esterifying two or more alcoholic hydroxyl groups of a polyhydric alcohol having two or more alcoholic hydroxyl groups with acrylic acid or methacrylic acid. Glycol diacrylate, ethylene glycol dimethacrylate, 1,3 butanediol diacrylate, 1,3 butanediol dimethacrylate, 1,4 butanediol acrylate, 1,4 butanediol methacrylate, 1,6 hexanediol diacrylate, 1,6 Hexanediol dimethacrylate, neopentyl glycol diacrylate, neopentyl glycol dimethacrylate, 2,2'bis (4-acryloxydiethoxyphenyl) propane, 2,2'bis (4-methacrylate) Roxydiethoxyphenyl) propane, glycerin dimethacrylate, glycerin triacrylate, glycerin trimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol diacrylate, pentaerythritol dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, pentaerythritol tetraacrylate, Pentaerythritol tetramethacrylate, tetramethylol methane diacrylate, tetramethylol methane dimethacrylate, tetramethylol methane triacrylate, tetramethylol methane trimethacrylate, tetramethylol tetraacrylate, tetramethylol tetramethacrylate, dimer diol diacrylate, Softimage ol dimethacrylate, and the like, particularly compounds containing three or more allyl esters or methacrylic esters are preferred. In addition, although said compound illustrated each single ester compound of acrylic acid and methacrylic acid, the form of mixed ester of acrylic acid and methacrylic acid may be sufficient.

  Any one of the rubber film adhesion improvers may be used alone, or two or more may be used in combination. Further, the adhesion improver used in the present invention is not limited to the above exemplary compounds.

  The compounding amount of the adhesion improver is 0.2 to 20 parts by weight, preferably 0.5 to 10 parts by weight with respect to 100 parts by weight of the total rubber component. On the contrary, when the amount exceeds 20 parts by weight, the effect of improving the adhesive strength reaches saturation and the physical properties of the rubber decrease. If necessary, reinforcing fillers, pigments, dyes, antioxidants, antioxidants, mold release agents, flame retardants, thixotropic agents, filler dispersants, and the like can be blended. Moreover, a peroxide can be mix | blended as an adhesive improvement promoter for promoting the adhesive improvement effect by said adhesive improvement agent.

  The method of blending the above compounding agent with rubber is not particularly limited. For example, when preparing a rubber compound, it may be performed using a rubber kneader such as a two-roll, Banbury mixer, or dough mixer (kneader). When a rubber is dissolved in a solvent and a film is formed by a casting method, the rubber compound may be dissolved in a solvent to prepare a solution, or may be added and blended with the obtained solution.

  The cover sheet of this invention controls the surface roughness of the rubber film. That is, the surface shape of the cover sheet is transferred to the surface of the uncrosslinked rubber film by utilizing the plasticity of the uncrosslinked rubber, and a film, fabric, paper, or the like whose surface shape is controlled is used. The cover sheet is preferably a film or a fabric because it is easier to handle if the waist is weak. The material is not particularly limited, and examples thereof include polyolefins represented by polyethylene and polypropylene, polyamides represented by polycaproamide and polyhexamethylene adipamide, polyesters represented by polyethylene terephthalate, and polyvinyl chloride.

  The surface roughness of the cover sheet is given by any means according to the surface roughness required for the rubber film. For example, in the case of using a film, in addition to a film having a mirror-finished surface, a method of blending fine particles inert to the polymer at the time of resin polymerization or film formation, mat processing, embossing, and the like can be mentioned. Further, when a fabric is used, a filament woven fabric such as taffeta is preferable, and the surface roughness can be variously controlled by the thickness and density of warp and weft. In addition, although thickness is not specifically limited, From the point of handleability and economical efficiency, the thing of a thin ground of about 0.015-0.10 mm is preferable.

  In this invention, the method of laminating the rubber film on the base film is arbitrary. For example, a solution obtained by dissolving the rubber composition in a solvent is applied to the surface of the base film and dried to form a rubber thin film. Examples thereof include a method, a method of forming a rubber thin film by extruding a rubber composition onto a surface of a base film under high pressure, and a calendar method. When liquid rubber such as liquid silicone rubber is used, a coating method may be used without diluting with a solvent. In addition, the thickness composition ratio of the rubber film and the base film in the present invention can be arbitrarily set according to the use of the composite.

  Also, the method for laminating the cover sheet is not particularly limited except that the surface of the cover sheet whose surface shape is controlled is directed to the rubber film surface side and is laminated before the crosslinking treatment, but the uncrosslinked rubber film composite is not limited. One method is to stack the above cover sheet on the rubber surface and to pass through a nip roll.

  In addition, the definition of the base film and the cover sheet in the present invention is determined by the configuration of the rubber film composite that is the final product. That is, the one integrated with the rubber film of the rubber film composite is the base film, and the one peeled off in the manufacturing process is the cover sheet. For example, when a rubber film composite is produced by performing a crosslinking treatment by electron beam irradiation on a laminate having a three-layer structure in which a rubber film and then a polyethylene film are laminated on a polyester film, the polyester film is used in the production of the laminate. Although it is a material film, in this invention, it is not necessarily a base film. That is, when the polyester film is peeled off after electron beam irradiation, the polyester film is a cover sheet and the polyethylene film is a base film.

  In this method, for example, in a method for producing a rubber film composite by coating a solution obtained by dissolving a rubber composition in a solvent, a film having poor solvent resistance such as a polyethylene film is used as a base film. This is a suitable method. That is, when a solution is applied to a polyethylene film, a satisfactory laminate cannot be obtained because the polyethylene film is eroded by a solvent and shrinkage wrinkles are formed. However, after the solution is applied to the polyester film and dried, the polyethylene film is When this polyethylene film is laminated and integrated with a rubber film as a base film, there is no shrinkage of the polyethylene film, and a practical laminate is obtained.

  On the other hand, when the polyethylene film is peeled off, the polyester film becomes the base film. Therefore, the method of laminating the rubber film on the base film described above is an example of the production method and is not limited to this. The conversion of the base film and the cover sheet can be performed by optimizing the electron beam irradiation conditions described later.

  In this invention, the base film, a non-cross-linked rubber film made of a rubber composition containing an adhesion improver, and a cover sheet are subjected to a cross-linking treatment by electron beam irradiation, and then the cover sheet is peeled off to form a base material. A rubber film composite consisting of a film and a rubber film is produced. The greatest feature of the present invention is that the total number of electron beams applied to the interface between the base film and the rubber film irradiated with the electron beam before peeling off the cover sheet. The purpose is to make the energy larger than the total energy of the electron beam applied to the interface between the cover sheet and the rubber film. As a result, it is possible to make a difference in the adhesive force between the rubber film and the base film and between the rubber film and the cover sheet. In other words, the adhesive force between the rubber film and the base film becomes stronger, while the adhesive force between the rubber film and the cover sheet becomes weaker and the cover sheet can be easily peeled off, and the rubber film composite having the desired surface roughness is obtained. You can get a body. This feature is based on the discovery of the phenomenon that each adhesive force between the rubber film and the base film and between the rubber film and the cover sheet is greatly influenced by the irradiation energy of the electron beam applied to each interface. .

  As a means for achieving the electron beam irradiation conditions, it is preferable to perform electron beam irradiation at least once from the base film side. In the electron beam irradiation, the energy of the electron beam is attenuated in the process of the electron beam passing through the substance, and the energy of the electron beam is weakened in proportion to the transmission distance. Therefore, when the electron beam is irradiated from the base film side, the energy between the base film and the rubber film becomes larger than that between the cover sheet and the rubber film, and the above-described requirements of the present invention can be achieved. . The attenuation of electron beam energy when passing through this substance is proportional to the acceleration voltage of the electron beam, and the attenuation increases as the acceleration voltage is lowered. Therefore, in order to increase the difference between the electron beam energies applied to the two interfaces, it is preferable to reduce the acceleration voltage of the electron beam.

  In addition, the value calculated by the approximate expression called EDMULT (Energydeposision in multilayer absorber) was used for the electron beam energy concerning said both interfaces. In addition, calculation is performed by R, Ito and T, Tabata: Radia.Center Osaka Prefect.Tech.Rep. 8 (1987).

  The optimum value of the energy of the electron beam applied to each interface varies greatly depending on the types of base film, rubber composition, cover sheet and adhesion improver, and the thickness of each constituent component, which are constituent requirements. I can't. Conditions should be set appropriately according to the target product. In general terms, in order to bring the peel strength of the cover sheet to a practical level, the electron beam energy applied to the interface between the cover sheet and the base film is preferably 2 Mrad or less.

  After the cover sheet is peeled off, the rubber film composite can be subjected to re-crosslinking treatment by electron beam irradiation, thereby completing the crosslinking of the rubber film. The electron beam irradiation at this time may be performed from either the base film side or the rubber film side. However, from the viewpoint of uniformizing the degree of crosslinking in the efficiency and thickness direction of the rubber film, high acceleration is performed from the surface side of the rubber film. It is preferable to carry out with voltage. Conditions for this electron beam irradiation can be appropriately set depending on the composition of the rubber component, the thickness of the rubber film, and the like.

  Moreover, in this invention, it is preferable to set the delamination strength of a rubber film and a base film to 4 N / 20 mm or more. Particularly preferable delamination strength is 6 N / 20 mm or more, and most preferable delamination strength is 8 N / 20 mm or more. When the delamination strength is less than 4 N / 20 mm, practicality is reduced because delamination is likely to occur between layers due to external force when the composite film is incorporated into a component or apparatus.

Reference embodiment 1
A rubber solution is obtained by dissolving 0.2 to 20 parts by weight of a polyhydric alcohol methacrylate with 100 parts by weight of silicone rubber and dissolving the resulting silicone rubber composition in a solvent such as toluene. After the solution is dried, it is applied to the surface of a polyester film (base film, thickness 0.01 to 0.3 mm) so that the thickness becomes 0.02 to 0.5 mm, dried, and polyethylene as a cover sheet on the rubber film surface. The film is pressure-bonded so that the surface having a controlled surface roughness is in contact with the rubber film, and the unevenness of the cover sheet is transferred to the surface of the rubber film, and then 100 to 1000 KV, 1 to 30 Mrad from the base film side. The pre-crosslinking is performed by irradiating the electron beam and the cover sheet is peeled off. Thereafter, the obtained composite is again guided to an electron beam irradiation apparatus, and post-crosslinking is performed by irradiating an electron beam of 100 to 1000 KV and 1 to 30 Mrad from the rubber film side. The obtained rubber film composite is a laminate of a silicone rubber film and a polyester film, and its delamination strength is 8 N / 20 mm or more.

  The rubber film composite has a strong delamination strength between the rubber film and the base film, and can be easily bonded to a desired equipment with a commercially available general-purpose adhesive by using the base film surface as an adhesive surface. It is practical because it is not peeled off from the interface between the rubber film and the base film by an external force. For example, when using a double-sided pressure-sensitive adhesive tape that is widely used when bonding rubber film to equipment, the adhesive force at the interface is strong, so there is no peeling at the interface when external force is applied. Peeling occurs at the adhesive part with the adhesive tape.

  Then, any irregularities such as a mirror surface and a satin finish are formed on the surface of the rubber film by transfer from the cover sheet.For example, when fine irregularities such as a satin finish are formed, the rubber film surface is raised on a drive table such as a compact disc. Thus, the grip and cushioning properties of the compact disc are improved when used after being bonded. In addition, it is a composite composed of a rubber film and a base film, and is firmer than a rubber film alone, so that it is excellent in workability when incorporated in an arbitrary apparatus. Therefore, the cushioning property of the rubber film can be fully utilized and used as a cushioning material or a sealing material.

Embodiment 1
A polyester film subjected to mat processing is used as a cover sheet, the rubber solution of Reference Embodiment 1 is applied to the mat processing surface, dried, and a polyethylene film is laminated as a base film on the rubber film surface and pressure-bonded. A rubber film composite composed of a polyethylene film and a silicone rubber film is obtained in the same manner as in Reference Example 1 except that the polyester film of the cover sheet is peeled off by pre-crosslinking by electron beam irradiation from the film side.

Reference embodiment 2
Using a liquid silicone rubber composition, the polyhydric alcohol methacrylic acid ester is immediately added and diluted without being diluted, and then applied to the surface of the polyester film (base film) and then dried without drying. Nylon taffeta is overlaid on the surface as a cover sheet, and the unevenness created by the warp and weft on the taffeta surface is transferred to the surface of the silicone rubber film by pressure bonding. The cover sheet is peeled off and post-crosslinked in order to obtain a rubber film composite having a thickness of 0.03 to 0.5 mm. The obtained rubber film composite has a textured unevenness transferred from the cover sheet on the surface of the silicone rubber film, and has a high interfacial peel strength between the silicone rubber film and the base film, and the rubber film composite of Reference Embodiment 1 Can be used in the same way as the body.

Reference embodiment 3
A rubber film composite comprising a laminate of an EPDM rubber film and a polyester film (base film) is obtained in the same manner as in Reference Embodiment 1 except that EPDM is used instead of the silicone rubber of Reference Embodiment 1. In this case, since the rubber film is made of EPDM, ozone resistance and heat aging resistance of the rubber film are improved as compared with the rubber film composite of Reference Embodiment 1.

Reference embodiment 4
The rubber composition of Reference Embodiment 1 or 3 is formed into a sheet shape with a calendar, the base film and the cover sheet are stacked and pressure-bonded, and pre-crosslinking by electron beam irradiation, peeling of the cover sheet and post-crosslinking are sequentially performed as described above. To obtain a rubber film composite. In addition, it may replace with a calendar and may shape | mold by extrusion.

  Hereinafter, the present invention will be described in detail by way of examples. In the following description, “parts” indicates parts by weight.

Reference example 1
As a silicone rubber compound, a commercially available high-strength silicone rubber compound and a commercially available silicone rubber compound for general molding are blended at a weight ratio of 60:40, and are kneaded at 100 to 200 ° C. using two rolls and have a thickness of 3 mm. A rubber sheet was formed. This unvulcanized rubber sheet is cut into 1 cm square pieces, which are weighed so that the weight ratio with respect to toluene is 23%, and put together with toluene into a stirrer equipped with a vacuum defoaming device. After stirring for 15 hours and dissolving the above strips in toluene, trimethylolpropane trimethacrylate was added to the solution so as to be 2 parts with respect to 100 parts of the silicone rubber compound, and after stirring uniformly, The vacuum deaerator was driven, and the mixture was further stirred for 20 minutes under a vacuum with a gauge pressure of −750 mmHg for defoaming.

  Next, the silicone rubber solution obtained by the above dissolution and defoaming is supplied to a roll coater, and the corona-treated surface of a 0.038 mm-thick polyethylene terephthalate film (base film) subjected to corona treatment has a thickness of 0 after drying. .15mm, then introduced into an oven, dried at 80 ° C, and the silicone rubber side surface is made of polyethylene, and one side is embossed to form a fine unevenness. The cover sheet is laminated so that the embossed surface faces silicone rubber, and is continuously laminated using a pressure roll at a pressure of 49 N / cm, and the resulting laminate is further led to an electron beam irradiation device. Irradiate an electron beam of 150 KV and 10 Mrad from the side of the base film to perform pre-crosslinking treatment, and then peel off the cover sheet, Obtain a complex of the total thickness 0.188mm made of Lum and polyester film was wound it into a roll. Then, the above composite is again guided to the electron beam irradiation device, and 200 kV and 10 Mrad of electron beam is irradiated from the silicone rubber film side to perform post-crosslinking treatment, and the embossed surface of the cover sheet is transferred well. A film composite was obtained.

Comparative Example 1
A silicone rubber film composite of Comparative Example 1 was produced in the same manner as in Reference Example 1 except that the addition of trimethylolpropane trimethacrylate was omitted in Reference Example 1.

Example 1
In Reference Example 1, a silicone rubber film composite was obtained in the same manner as in Reference Example 1 except that the electron beam irradiation of the pre-crosslinking treatment was performed from the cover sheet side. In this case, the cover sheet is a rubber film base film.

Reference example 2
In Reference Example 1, the addition amount of trimethylolpropane trimethacrylate was 1 part, and a polyester-based adhesion improver (terephthalic acid, isophthalic acid, sodium 3-sulfoisophthalic acid on both sides of the polyester film as a base film. Reference Example 1 except that an easy-adhesive polyethylene terephthalate film laminated with a polyester comprising a salt, ethylene glycol, diethylene glycol and neopentyl glycol) and a matte-processed 0.05 mm thick polyethylene film as a cover sheet are used. Similarly, a silicone rubber film composite was obtained. The surface of the silicone rubber film corresponds to the surface of the cover sheet and has a surface roughness lower than that of Reference Example 1.

Comparative Example 2
In Reference Example 2, a silicone rubber film composite was obtained in the same manner as Reference Example 2 except that the addition of trimethylolpropane trimethacrylate was omitted.

Example 2
In Reference Example 2, a silicone rubber film composite was obtained in the same manner as in Reference Example 2 except that the electron beam irradiation of the pre-crosslinking treatment was performed from the cover sheet side. In this case, the cover sheet is a rubber film base film.

Reference example 3
In Reference Example 2, (1) a commercially available high-strength silicone rubber compound, a commercially available silicone rubber compound for general molding, and a commercially available conductive silicone rubber compound were used as the silicone rubber compound, and the ratio was 70:10:20. (2) Nylon taffeta as cover sheet, (3) Silicone rubber film composite as in Reference Example 2 except that the acceleration voltage of electron beam during pre-crosslinking treatment is 200 KV and energy is 2 Mrad The body was manufactured. It should be noted that the nylon taffeta texture was clearly transferred onto the surface of the silicone rubber film of the composite.

Comparative Example 3
In Reference Example 3, when the cover sheet was peeled off without performing pre-crosslinking treatment, the silicone rubber film adhered to the nylon taffeta, and the rubber film composite laminated with the base film could not be produced.

Comparative Example 4
In Reference Example 3, a silicone rubber film composite was produced in the same manner as Reference Example 3 except that the blending of trimethylolpropane trimethacrylate was omitted.

Example 3
In Reference Example 3, a silicone rubber film composite was obtained in the same manner as in Reference Example 3 except that the electron beam irradiation of the pre-crosslinking treatment was performed from the cover sheet side. In this case, the cover sheet is a rubber film base film.

Reference example 4
In Reference Example 2, a silicone rubber film composite was produced in the same manner as in Reference Example 2, except that trimethylolpropane triacrylate was used as the adhesion improver and the blending amount was 4 parts by weight.

Example 4
In Reference Example 4, a silicone rubber film composite was produced in the same manner as in Reference Example 4 except that the pre-crosslinking treatment with electron beam irradiation was performed from the cover sheet side. In this case, the cover sheet is a rubber film base film.

Example 5
In Reference Example 3, a polyethylene terephthalate film having a thickness of 0.075 mm subjected to sand mat processing as a polyester film was used, and a silicone rubber solution was applied to the sand mat processing surface, and the amount of trimethylolpropane trimethacrylate was 4 parts by weight. A laminate was obtained in the same manner as in Reference Example 3 except that a 0.05 mm thick polyethylene film subjected to corona treatment was used as the polyethylene film. The polyethylene film was laminated with the corona-treated surface aligned with the rubber surface.

  The above laminate is guided to an electron beam irradiation apparatus, irradiated with an electron beam of 150 KV and 15 Mrad from the polyethylene film side to give a pre-crosslinking treatment, and then the polyethylene terephthalate film is peeled off, and consists of a silicone rubber film and a polyethylene film. A composite having a total thickness of 0.20 mm was wound into a roll. The composite is again guided to an electron beam irradiation apparatus, and 200 KV, 10 Mrad of electron beam is irradiated from the silicone rubber film side to perform post-crosslinking treatment, and the silicone rubber having the sand mat processed surface of the polyester film transferred well. A silicone rubber film composite comprising a film and a polyethylene film was obtained.

Comparative Example 5
In Example 5, a silicone rubber film composite was obtained in the same manner as in Example 5 except that the blending of trimethylolpropane trimethacrylate was omitted.

Reference Example 5
EPDM (ethylene content: 34%) was used as the rubber, and kneaded by a conventional method with the following composition.
EPDM 100.0 parts Polyethylene glycol 2.5 parts Stearic acid 0.5 parts Anti-aging agent A 1.5 parts Anti-aging agent B 0.7 parts Phenol / formaldehyde resin 2.0 parts MAF carbon 30.0 parts FT carbon 40 0.0 part naphthenic plasticizer 15.0 parts NN'-m phenylenedimaleimide 1.5 parts 2,5-dimethyl-2,5-di (t-butylperoxy) hexane 5.0 parts

  The kneaded rubber is molded into a rubber sheet having a thickness of 10 mm, the unvulcanized rubber sheet is cut into 1 cm square pieces, and the pieces are weighed so that the weight ratio to toluene is 30%. After putting into a stirrer with a vacuum defoaming device together with toluene and stirring for 15 hours under atmospheric pressure to dissolve the above fine pieces in toluene, trimethylolpropane trimethacrylate is added to the solution to 12 parts with respect to 100 parts of EPDM. After stirring uniformly, the vacuum deaerator was driven, and the mixture was further stirred for 20 minutes under vacuum with a gauge pressure of −750 mmHg to degas.

  The obtained EPDM rubber solution was supplied to a roll coater, applied to the easy-adhesive polyethylene terephthalate film (base film) used in Reference Example 2 so that the thickness after drying was 0.25 mm, and then introduced into an oven. And dried at 80 ° C., the embossed surface of the cover sheet used in Reference Example 1 is laminated on the rubber side surface, and the layers are continuously laminated while pressing at a pressure of 49 N / cm. Lead to the irradiation device, irradiate 150KV, 15Mrad of electron beam from the base film side, pre-crosslinking treatment, and then peel off the cover sheet to obtain a composite consisting of EPDM rubber film and polyester film. Guided again to the electron beam irradiation device, irradiated with an electron beam of 200 KV and 15 Mrad from the EPDM rubber film side to perform post-crosslinking treatment, and had a total thickness of 0.28. Wound into a roll to obtain a EPDM rubber film composite mm.

Comparative Example 6
In the above Reference Example 5, an EPDM rubber film composite of Comparative Example 6 was obtained in the same manner as in Reference Example 5 except that the addition of trimethylolpropane trimethacrylate was omitted.

Example 6
In Reference Example 5, an EPDM rubber film composite was obtained in the same manner as in Reference Example 5 except that the electron beam irradiation of the pre-crosslinking treatment was performed from the cover sheet side. In this case, the cover sheet is a rubber film base film.

Reference Example 6
Using the silicone rubber compound, the base material film (polyester film) and the cover sheet (polyethylene film) of Reference Example 2, the same composition as Reference Example 2 was laminated by the calendar method, and the obtained laminate was referred to Reference Example 2 and The same electron beam irradiation treatment was performed to obtain a silicone rubber film composite.

  The peel strength of the cover sheet and the peel strength of the base film with respect to the rubber film in the composites of the above Reference Examples, Examples and Comparative Examples were tested by the T-type peel method according to JIS K6854, respectively. The results are shown in Table 1 below. In the table, “reference” indicates a reference example, “actual” indicates an example, and “ratio” indicates a comparative example. TMP means trimethylolpropane trimethacrylate. Moreover, what attached | subjected "super" by peeling strength means that the rubber film was damaged at the time of a measurement. Further, the “base side” of the interfacial energy and peel strength indicates between the rubber film and the base film, and the “front side” indicates between the rubber film and the cover sheet. In addition, * is what performed electron beam irradiation from the cover sheet side.

  As shown in Table 1, in Example 5 and Reference Examples 1-6, the delamination strength of the rubber film / cover sheet is low, the cover sheet can be smoothly peeled, and the embossed surface of the cover sheet Further, the matted surface, the texture and the like were transferred well, and the delamination strength of the rubber film / base film was high, so that the base film did not peel off and was excellent in practicality. These rubber film composites can be bonded to equipment with a general-purpose adhesive when the surface of a polyester film or polyethylene film as a base film is used as an adhesive surface. Since the adhesive force between the films was strong, it did not peel off at the interface between the two due to external force, and was excellent in practicality. For example, when the base film side is bonded to any equipment with a double-sided adhesive tape, even if an attempt is made to peel off the rubber film, the peeling does not occur between the rubber film and the base film. woke up. Further, the above composite was stronger than a single rubber film, was easy to handle when incorporated into an apparatus or component, and was excellent in workability.

  On the other hand, in Comparative Examples 1, 2, 4, 5, and 6, since the compounding of the adhesion improver was omitted, the delamination strength of the rubber film and the base film was remarkably lowered, and the composite was incorporated into the apparatus and parts. At that time, delamination easily occurred with weak external force, and lacked practicality. In Examples 1, 2, 3, 4, and 6, since the electron beam irradiation of the pre-crosslinking treatment was performed from the cover sheet side, the delamination strength of the rubber film / cover sheet was increased, and the cover sheet was smoothly peeled off. Could not be done. Further, in Comparative Example 3, since the pre-crosslinking treatment was omitted, as described above, rubber adhered to the cover sheet when the cover sheet was peeled off, and a composite body could not be manufactured.

Claims (4)

Crosslinking of a laminate of an uncrosslinked rubber film and a cover sheet comprising a base film, a rubber composition comprising at least one compound selected from an acrylic acid derivative and a methacrylic acid derivative as an adhesion improver by electron beam irradiation In a method for producing a rubber film composite comprising a base film and a rubber film by performing a treatment and then peeling the cover sheet,
The laminate is a laminate in which an interlayer adhesion between the base film and the rubber film is weaker than an interlayer adhesion between the rubber film and the cover sheet,
By performing the electron beam irradiation at least once from the base film side, the total energy of the electron beam applied to the interface between the base film and the rubber film of the electron beam irradiation performed before peeling the cover sheet is determined. A method for producing a rubber film composite, wherein the total energy of an electron beam applied to an interface of the film is made larger. Crosslinking of a laminate of an uncrosslinked rubber film and a cover sheet comprising a base film, a rubber composition comprising at least one compound selected from an acrylic acid derivative and a methacrylic acid derivative as an adhesion improver by electron beam irradiation In a method for producing a rubber film composite comprising a base film and a rubber film by performing a treatment and then peeling the cover sheet,
The laminate is a laminate in which an uncrosslinked rubber film is formed on a cover sheet surface by a coating method, and then a base film is pasted on the uncrosslinked rubber film, and in the coating method of the base film It is a laminate in which the solvent resistance is inferior to the solvent resistance of the cover sheet,
By performing the electron beam irradiation at least once from the base film side, the total energy of the electron beam applied to the interface between the base film and the rubber film of the electron beam irradiation performed before peeling the cover sheet is determined. A method for producing a rubber film composite, wherein the total energy of an electron beam applied to an interface of the film is made larger.   The coating method is a method in which a solution obtained by dissolving the rubber composition in a solvent is applied to the surface of the cover sheet and dried to form a rubber thin film, or liquid rubber is applied to the surface of the cover sheet. 3. The method for producing a rubber film composite according to claim 2, wherein the method is a method of forming a rubber thin film.   The method for producing a rubber film composite according to claim 1, wherein the cover sheet is a polyester sheet, and the base film is a polyolefin film.