JPH11320762A - Composite rubber film for adhesion and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stick on an article using no pressure sensitive adhesive in order to fix the article provisionally to another article or in order to cover/protect the surface by forming the adhesive surface, whose average surface roughness is not exceeding a specified value, of a rubber film to be laminated on at least one side of a polyester backing film. SOLUTION: A rubber film is laminated at least on one side of a polyester backing film having appropriate rigidity in order to form the surface of the rubber film whose average surface roughness (Ra) is not exceeding 0.12 μm. Since a backing film is made of a polyester having proper rigidity, the dimensional stability and handling of the composite rubber film are good, and since the surface roughness of the rubber film is not exceeding a specified value, when the surface is pressed on the smooth surface of an article, the composite rubber film for adhesion is bonded strongly without an adhesive and can be peeled off easily by peeling one end. Natural rubber, silicone rubber, and others, or mixtures are used as the rubber constituting the rubber film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite rubber film to be used for fixing an article or protecting the surface of the article, and a method for producing the same.

[0002]

2. Description of the Related Art In various fields, an adhesive sheet or an adhesive tape is widely used for fixing an article or protecting the surface of the article. In the case of fixing an article, for example, exposure and washing of a plate during photoengraving,
There is a temporary fixation of a plate and a printing substrate during printing. Further, there is a temporary fixing of a work such as a wafer in a semiconductor manufacturing process and a temporary fixing of a work in a processing step of a precision glass component such as an optical glass filter and other precision components.
On the other hand, as a case of protecting the surface of an article, there is an example in which the surface is temporarily covered in the processing steps of various articles and then peeled off after finishing the processing.

[0003] In the above-mentioned temporary fixing and surface protection, good releasability as well as fixing force are required, but conventional adhesive sheets and adhesive tapes require the adhesiveness of an adhesive layer laminated on one side or both sides of a support. It is intended to be attached to and detached from goods using
By changing its adhesive properties, it can be used for various applications, and is used in a wide range of industrial fields. However, since the pressure-sensitive adhesive layer is used, when the above-mentioned sheet or tape is peeled off, the pressure-sensitive adhesive is transferred to the above-mentioned article, and there is a problem that the surface of the article is contaminated. Moreover, since the pressure-sensitive adhesive generally has low heat resistance, the above-mentioned pressure-sensitive adhesive tape or pressure-sensitive adhesive sheet cannot be used when drying or heat-treating the article.

[0004]

SUMMARY OF THE INVENTION The present invention utilizes an adhesive force (tack force) generated when smooth surfaces come into contact with each other, thereby adhering the article to an article without using an adhesive and attaching the article to another article. It can be temporarily fixed to an article, can protect the surface of an article, and has excellent heat resistance, allowing the article to be dried or heat-treated while being adhered to the article. Things.

[0005]

According to a first aspect of the present invention, there is provided a composite rubber film obtained by laminating a rubber film on at least one surface of a base film made of polyester. The surface of the rubber film is formed as an adhesive surface having an average surface roughness (Ra) of 0.12 μm or less.

The above-mentioned composite rubber film for application is a composite of a rubber film and a base film. Since the base film is made of polyester having a suitable rigidity, the dimensional stability and handleability of the composite rubber film are improved. Becomes better,
Moreover, since the average surface roughness (Ra) of the surface of the rubber film is 0.12 μm or less, when the rubber film surface is pressure-bonded to the smooth surface of the article, the composite rubber film to be adhered without an adhesive is firmly attached, Thereafter, the composite rubber film to be adhered can be easily peeled off by turning it from one end. Further, since no pressure-sensitive adhesive or other adhesive is used, it has excellent heat resistance and can be used for drying or heat-treating the above-mentioned article.

The rubber constituting the rubber film of the present invention is not particularly limited, and natural rubber (NR), silicone rubber (Q), ethylene propylene rubber (EPDM), acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR) ), Chloroprene rubber (CR), acrylic rubber (ACM), and fluoro rubber (FKR), or a mixture of any two or more of them.

It is preferable that the rubber is compounded with an adhesion improver for improving the adhesion to a polyester base film as an additive, as described in claim 2, whereby the surface of the rubber film becomes an article. It is possible to prevent peeling between the rubber film and the base film before peeling from the rubber film. For this reason, the interlayer peel strength of the rubber film / base film is preferably 5 N / 20 mm or more, particularly preferably 7 N / 20 mm or more.

The above-mentioned adhesion improver is preferably a compound containing a reactive group active against a radical reaction. Examples of the compound include an acrylic acid derivative, a methacrylic acid derivative, and an allylic acid derivative. Among them, a derivative having two or more, particularly three or more unsaturated bonds is preferable. These compounds are widely used as co-crosslinking agents for rubber, and include acrylic acid esters and methacrylic acid esters of polyhydric alcohols, allyl esters of polyvalent carboxylic acids, triallyl isocyanurate, triallyl cyanurate and the like. .

The acrylate or methacrylate of the polyhydric alcohol 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. For example, ethylene 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, neo Pentyl glycol dimethacrylate, 2,
2'bis (4-acryloxydiethoxyphenyl) propane, 2,2'bis (4-methacryloxydiethoxyphenyl) pron, 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 triacrylate Methacrylate, tetramethylol tetraacryl Over DOO, tetramethylolmethane tetramethacrylate, dimer diol diacrylates, dimer diol dimethacrylate and the like, particularly compounds containing three or more allyl esters or methacrylic esters are preferred. In addition, although the said compound illustrated each single ester compound of acrylic acid and methacrylic acid, it may be in the form of a mixed ester of acrylic acid and methacrylic acid.

Further, examples of the allyl ester of a polyvalent carboxylic acid include phthalic acid diallylate, trimellitic acid diallylate, and pyromellitic acid tetraarylate.

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

The compounding amount of the above-mentioned adhesion improving agent is 0.2 to 20 parts by weight, preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the whole rubber component. If the adhesive strength to the material film is insufficient, and if it exceeds 20 parts by weight, the effect of improving the adhesive strength reaches saturation and the physical properties of the rubber deteriorate. In addition, if necessary, reinforcing fillers, pigments, dyes, antioxidants, antioxidants, release agents,
A flame retardant, a thixotropic agent, a filler dispersant, and the like can be added. In addition, a peroxide can be blended as an adhesion improving agent for promoting the effect of improving the adhesion by the above-mentioned adhesion improving agent.

The method of compounding the above compounding agent with rubber is not particularly limited. For example, when a rubber compound is produced,
This may be performed using a rubber kneading machine such as a roll, a Banbury mixer or a dough mixer (kneader). Alternatively, when the rubber is dissolved in a solvent and the film is formed by a casting method, the rubber compound is dissolved in the solvent. It may be added and blended either when preparing the solution or after forming the solution.

As the base film serving as a support for the rubber film, any polyester film containing polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate or the like as a main component can be used.

The base film is preferably one in which the surface on the side on which the rubber film is laminated is treated with an actinic ray or an easy-adhesion layer made of a compound for improving the adhesion is laminated on the surface. The use of these easily-adhesive polyester films makes it possible to reduce the amount of the adhesion improver to the rubber film.

Examples of the treatment method using the actinic ray include corona discharge treatment, ultraviolet irradiation treatment, plasma treatment, and flame treatment. Examples of the compound for the easy adhesive layer that improves the adhesiveness by lamination include polyester-based, polyurethane-based, and polyacryl-based polymers or a mixture thereof. The method of laminating the easily adhesive layer may be a so-called in-line method of laminating at the time of film formation or a so-called off-line method of laminating on a formed film. Further, the surface of the easy-adhesion layer of the film on which the easy-adhesion layer is laminated can be treated with the above-mentioned actinic ray.

The substrate film of the present invention may have a multilayer structure. For example, a composite rubber film obtained by laminating a polyester film having a low melting point on the above-mentioned polyester film and laminating a rubber film on the film surface on the high melting point side has a film surface on the low melting point side, for example, heat applied to an arbitrary substrate on the fixed side. Adhesion becomes possible, and the application field as a composite rubber film to be attached is expanded.

In the present invention, the rubber film is laminated on at least one surface of the base film. That is,
A rubber film may be laminated on both sides of the base film, and in this case, it can be used as a double-sided adhesive tape.
The thickness of each of the rubber film and the base film can be arbitrarily set, but when cushioning is required, the thickness of the rubber film is preferably 10 μm or more. Further, from the viewpoint of handleability, the thickness of the base film is preferably 8 μm or more. The upper limit of the thickness can be appropriately determined according to the application, but is generally preferably 1 mm or less.

[0020] In the composite rubber film to be stuck according to the present invention, an uncrosslinked rubber composition containing an adhesion improving agent is laminated on at least one surface of a base film made of polyester, and then crosslinked. In the method for producing a composite rubber film, the surface of the rubber film obtained by laminating the rubber composition has an average surface roughness (Ra) of 0.12 μm.
It can be manufactured by forming on an adhesive surface of m or less.

As a method of laminating the uncrosslinked rubber on the base film, a rubber solution obtained by dissolving a rubber composition in a solvent is applied to the surface of the base film and dried to form a rubber thin film. And a method of extruding the rubber composition on the surface of the base film under high pressure to form a rubber thin film, a calendering method, and the like. When a liquid rubber such as a liquid silicone rubber is used, it may be applied without being diluted with a solvent.

In the production method of the present invention, a cross-linking treatment is performed after the above-mentioned lamination, and a cross-linking reaction of the rubber proceeds by the cross-linking treatment, and at the same time, an adhesive force is developed between the rubber film and the base film. When the rubber film is in an unvulcanized state, the adhesive strength between the rubber film and the base film is low, and even when the vulcanized rubber film is laminated on the base film, the adhesive strength is not exhibited. And even if an adhesiveness improving agent or an adhesiveness improving accelerator is compounded in the rubber film, or an easy-adhesive layer is laminated on the base film, the adhesiveness improving effect is obtained in the unvulcanized state described above. It does not appear unless lamination is performed and crosslinking treatment is performed after lamination.

The crosslinking method is also optional. For example, a peroxide may be added to the rubber composition, and after laminating the base film as described above, the laminate may be cross-linked by heat treatment. Crosslinking may be carried out by irradiation with actinic rays such as electron beams and γ rays. The addition of various auxiliaries in these crosslinking treatments is not limited at all.

In the present invention, it is essential that the average surface roughness (Ra) of the rubber film surface is 0.12 μm or less, but the means for achieving this is arbitrary. For example, claim 7
As described in above, the cover film having an average surface roughness (Ra) of 0.12 μm or less is laminated on the surface of the uncrosslinked rubber film, and the cover film is peeled off before or after the crosslinking treatment. .

The above cover sheet has an average surface roughness (R
If a) is 0.12 μm or less, the type, thickness and the like are not particularly limited. Preferred examples include polyesters, polyolefins, polyacryls, and polyamides. The thickness is preferably from 10 to 200 μm.

This cover film is finally peeled from the rubber film surface of the composite rubber film. The peeling time may be before or after the crosslinking treatment,
Considering that the surface of the composite rubber film can be protected by the cover film, it is preferable that the cover film be peeled off after the crosslinking treatment and immediately before the use of the composite rubber film. Therefore, this cover film is, as described in claim 4,
It should be laminated releasably on the surface of the rubber film, and its delamination strength is smaller than the delamination strength of the rubber film / substrate film, specifically, as described in claim 5, 4N / 20 mm or less, particularly preferably 3 N / 20 mm or less, more preferably 2 N / 20 mm or less.

As described above, as a method of controlling the delamination strength of the rubber film to the cover film to be lower than the delamination strength of the base film, the surface treatment is performed on the base film as described above. For example, selecting a material having low adhesiveness. Further, since the adhesive strength is developed as the crosslinking reaction of the rubber proceeds, it is preferable to select an adhesiveness improving agent and to optimize the crosslinking means and crosslinking conditions. In addition, multilayered rubber film,
In addition, it is possible to make a difference in the concentration of the adhesion improving agent between the base film side and the cover film side.

As described above, the adhesive rubber composite film of the present invention utilizes the fact that the rubber film surface exhibits a strong adhesive force with the smooth surface of the article. The above-mentioned adhesive strength is obtained by using a polyethylene terephthalate film (average surface roughness Ra: 0.05 μm or less) as the above-mentioned article, and the tensile shear adhesive strength between the polyethylene terephthalate film (hereinafter, referred to as “article film”). 1N / cm ² or more, especially 2 N / cm
^It is preferably at least ^{2 and} more preferably at least 3 N / cm ² . When used for temporary fixing or temporary surface protection, the peeling strength from the article is preferably lower, contrary to the above-mentioned adhesive strength, and the peeling adhesive strength with the article film is 1 N / 20 mm.
0.5N / 20mm or less, especially 0.3N / 2
0 mm or less is preferable.

[0029]

Embodiment 1 After dissolving a silicone rubber composition in toluene, 0.2 to 20 parts by weight of a polyhydric alcohol methacrylate is blended with 100 parts by weight of the above composition and stirred. A polyethylene terephthalate base film (thickness:
50-500 μm) with a thickness of 10-500 after drying on the surface
μm and dried in an oven, and then a cover film made of polymethylpentene (thickness: 10-200 μm, average surface roughness: 0.1
(2 μm or less) is pressed so that the surface whose surface roughness is controlled is in contact with the rubber film.

Next, the electron beam (10
0 to 1000 KV, 2 to 30 Mrad), followed by irradiating the same electron beam as described above from the cover film side to carry out a crosslinking treatment.
A laminate is obtained in which cover films are laminated on opposite sides.

In the obtained laminate, the delamination strength on the cover film side is 4 N / 20 mm or less, while the delamination strength on the opposite substrate film side is 5 N / 20 mm or more. Easily peeled off from the rubber film surface. However, the composite rubber film does not separate into the rubber film and the base film, and the rubber film does not peel off from the base film together with the cover film.

When the rubber film surface of the composite rubber film exposed by peeling the cover film is pressed against the smooth surface of the article, for example, the surface of an article film made of polyethylene terephthalate, the adhesive force between the article film and the rubber film is obtained. And its size is 1 N / cm ² or more in terms of tensile shear adhesive strength, so that it can be used for temporarily fixing an article or protecting the surface of an article. Moreover, the peel adhesive strength between the composite rubber film attached to the article and the article, for example, the above-mentioned article film is 1N / 2.
Since it is 0 mm or less, the composite rubber film can be easily peeled off by turning the composite rubber film from one end. Since this composite rubber film uses silicone rubber, it is particularly suitable for applications requiring heat resistance.

Embodiment 2 To 100 parts by weight of EPDM, 0.2 to 20 parts by weight of an acrylic acid ester of a polyhydric alcohol in addition to a usual compounding agent are mixed and kneaded, and the obtained EPDM composition is preliminarily mixed with a polyester. 10 to 5 by a calender method on the above-mentioned easy-adhesion layer of a polyester film having
After laminating to a thickness of 00 μm, a cover film was laminated in the same manner as in Embodiment 1 above, a cross-linking treatment was performed by electron beam irradiation from the substrate film side, and after the cover film was peeled off, the exposed rubber film surface A cross-linking treatment by electron beam irradiation is performed to produce a composite rubber film. The obtained composite rubber film has almost the same performance as that of the composite rubber film to be adhered of Embodiment 1 and uses EPDM, so that it is particularly suitable for applications requiring adhesiveness.

Embodiment 3 An uncrosslinked rubber film and a cover film are sequentially laminated on the base film surface of the composite rubber film with a cover film obtained by laminating and crosslinking according to the method of Embodiment 1 in the same manner as described above. Electron beam irradiation is performed from the cover film side of the uncrosslinked rubber film to produce a double-sided adhesive composite rubber film having rubber films on both sides of the base film.
In addition, an uncrosslinked rubber film and a cover film may be sequentially laminated on both surfaces of the base film, and then a crosslinking treatment may be performed by electron beam irradiation from one cover film side and the other cover film side.

[0035]

EXAMPLES Various rubber composite films to be adhered were produced using various rubbers, and their performance was tested. Hereinafter, the details of the representative examples will be described. In the following description, "part"
Indicates parts by weight. In the performance test, the measurement method was as described below.

Delamination strength A knife is inserted into the interface between the rubber film and the base film or cover film, and a force is applied to the portion or the portion is immersed in toluene to cause interfacial separation.
It was measured by a T-type peeling method according to IS K6854.

Tensile shear adhesive strength An article film ("Polyester film E500" manufactured by Toyobo Co., Ltd.)
0, average surface roughness Ra: 0.05 μm or less, thickness: 50
μm) were overlaid, pressed with a finger, and measured according to JIS K6850.

Peel Adhesive Strength In the same manner as in the measurement of the tensile shear adhesive strength, a sample obtained by pressing a composite rubber film on an article film according to JIS K6 was used.
It was measured according to 854.

Average Surface Roughness (Ra) The average surface roughness was measured using an SE-200 type surface roughness meter manufactured by Kosaka Laboratory under the following conditions. Vertical magnification: 1000 Horizontal magnification: 20 Cut-off: 0.08 mm Measurement length: 8 mm Measurement speed: 0.1 mm

Example 1 A commercially available silicone rubber composition (rubber hardness: 40 degrees) was
The mixture was kneaded at 100 ° C. using two rolls to form a rubber sheet having a thickness of 3 mm. This unvulcanized rubber sheet is cut into 1 cm square pieces, weighed so that the weight ratio to toluene is 23%, and put into a stirrer with a vacuum defoaming device together with toluene, and the atmospheric pressure is reduced. After dissolving the strips in toluene for 15 hours under stirring, trimethylolpropane trimethacrylate was added to the solution in an amount of 2 parts based on 100 parts of the silicone rubber compound, and the mixture was stirred uniformly. The vacuum defoaming device was driven, and the mixture was further stirred for 20 minutes under vacuum at a gauge pressure of -750 mmHg to defoam.

Next, the silicone rubber solution obtained by the above dissolution and defoaming was supplied to a roll coater, and dried on a corona-treated surface of a 188 μm-thick polyethylene terephthalate film (base film) which had been subjected to corona discharge treatment in advance. It is applied so as to have a thickness of 300 μm, subsequently introduced into an oven and dried at 80 ° C., and a cover film made of polymethylpentene is applied on the surface (average surface roughness (Ra): 0.025 μm, thickness: 100 μm) Were laminated. Next, the obtained laminate was introduced into an electron beam irradiation device, and irradiated with an electron beam of 200 KV and 15 Mrad from the side of the substrate film. Subsequently, the above laminate was introduced again into the electron beam irradiation device, and 500 KV, 5 KV from the cover film side.
The laminate of the composite rubber film and the cover film was wound into a roll by irradiation with an electron beam of Mrad.

The delamination strength between the composite rubber film and the cover film of the obtained laminate was 1.2 N / 20 mm,
Excellent peelability. Further, the interlayer peel strength of the silicone rubber film and the base film constituting the composite rubber film was such that the silicone rubber film was damaged at the time of measurement, and the peel strength was judged to be 18 N / 20 mm or more.

In the composite rubber film obtained by removing the cover film from the laminate, the average surface roughness (Ra) of the rubber film surface was 0.025 μm. Was as high as 9 N / cm ^2, and the adhesive strength to an article having a smooth surface was strong. On the other hand, when the article film is adhered to the rubber surface, the peel adhesion strength is 0.1 N / 20.
mm and were excellent in peelability. That is, the sticking composite rubber film of Example 1 has a strong fixing force of the article and also has good releasability. Furthermore, since this composite rubber film does not use an adhesive and utilizes the adhesive force of the rubber film itself, even if the fixed article is peeled off, the surface of the article is not contaminated by the adhesion of the adhesive. . Therefore,
The above-mentioned composite rubber film can be used in a wide range of industrial fields as a sheet or tape for temporarily fixing a printing plate or other articles and for covering and protecting the surface of the article, and is particularly practical for fixing a printing plate.

Comparative Example 1 The procedure of Example 1 was repeated, except that a mat type polymethylpentene film having an average surface roughness (Ra) of 0.54 μm was used as the cover film. A composite rubber film to be worn was manufactured. In this composite rubber film, the average surface roughness (Ra) of the rubber film surface is 0.54 μm, and the tensile shear adhesive strength of the rubber film / article film of the composite rubber film is as low as 0.1 N / cm ² or less. However, it is not practical for fixing articles or protecting coatings.

Comparative Example 2 A laminated composite rubber film of Comparative Example 2 was produced in the same manner as in Example 1 except that the addition of trimethylolpropane trimethacrylate was omitted. The composite rubber film of Comparative Example 2 had a low interlayer peel strength of 0.2 N / 20 mm between the rubber film and the base film, and lacked practicality.

Example 2 EPDM (ethylene content 34%, manufactured by Nippon Synthetic Rubber Co., Ltd.)
2.5 parts of polyethylene glycol (molecular weight 4000) and 0.5 parts of stearic acid per 100 parts of "EP21")
Parts, zinc salt of 2-mercaptobenzimidazole (“Nocrack MBZ”, manufactured by Ouchi Shinko Chemical Co., Ltd.)
Part, 4,4- (α, α-dimethylbenzyl) diphenylamine (“Nocrack CD” manufactured by Ouchi Shinko Chemical Co., Ltd.)
0.7 parts, phenol formaldehyde 2.0 parts,
40.0 parts of FT carbon, 15.0 parts of polybutene,
4 parts of trimethylolpropane triacrylate were mixed and kneaded by a conventional method.

The obtained rubber composition was applied to a 188 μm-thick polyester film (substrate film) which had been surface-treated with a polyester-based surface treating agent to a thickness of 3
It is laminated so as to have a thickness of 50 μm, and an ethylene / methyl methacrylate copolymer (manufactured by Sumitomo Chemical Co., Ltd.,
"Aclift CM") and a mixture of polyethylene and have an average surface roughness (Ra) of 0.040 μm and a thickness of 1
A 00 μm gloss type cover film was laminated.
The obtained laminate was introduced into an electron beam irradiation device, and irradiated with 150 KV and 25 Mrad of electron beam from the substrate film side.
After the cover film was peeled off, the composite rubber film was again introduced into the electron beam irradiation device, and 300 mm from the rubber film side.
An electron beam irradiation of KV, 15 Mrad was performed.

The obtained composite rubber film for adhesion has a rubber film / base film with an interlayer peel strength of 19 N / 20.
mm and high practicality. The average surface roughness (Ra) of the rubber film surface is 0.038 μm, and the tensile shear adhesive strength of the rubber film / article film is 12
It was as high as N / cm ^2, and had a strong adhesive strength to an article having a smooth surface. The peel adhesion strength of the rubber film / article film was as low as 0.2 N / 20 mm or less, and the peelability was good. That is, similarly to the composite rubber film of Example 1, the fixing force of the article is strong, and the releasability is also good.
For example, it was highly practical for fixing a printing plate.

Comparative Example 3 In Example 2, the average surface roughness (R
A laminated composite rubber film of Comparative Example 3 was produced in the same manner as in Example 2 except that a) was increased to 0.15 μm by blending titanium oxide. The resulting composite rubber film had an average surface roughness (Ra) of the rubber film surface of 0.1.
It was 4 μm, the tensile shear adhesive strength of the rubber film / article film was as low as 0.2 N / cm ^2, and the practicability was low.

Comparative Example 4 A laminated composite rubber film of Comparative Example 4 was produced in the same manner as in Example 2 except that the addition of trimethylolpropane trimethacrylate was omitted. The delamination strength of the obtained composite rubber film is 0.1 N / 20.
mm, which was inferior in practicality.

Example 3 In Example 1, a rubber composition having a rubber hardness of 50 degrees was used as a silicone rubber compound, and a 50 μm-thick polyethylene terephthalate film treated with a polyester-based surface treating agent was used as a base film.
An uncrosslinked composite rubber film with a cover film was laminated in the same manner as in Example 1 except that the rubber thickness after drying was changed to 50 μm. The laminate was introduced into an electron beam irradiation device, irradiated with an electron beam of 250 KV and 12 Mrad from the substrate film side, and then wound into a roll.

The resulting composite rubber film / cover film had low interlaminar peel strength of 1.5 N / 20 mm, and the cover film was easily peeled. Further, the interlayer peel strength of the rubber film / base film was determined to be 8 N / 20 mm or more because the rubber film was damaged during the measurement. Also,
The average surface roughness (Ra) of the rubber film after peeling the cover film is 0.024 μm.
The tensile shear strength of the article film was as high as 7 N / cm ² , and the peel adhesive strength was as low as 0.1 N / 20 mm, indicating excellent practicability. The composite rubber film was suitable as a sheet for temporarily fixing the disk when printing on a compact disk and for protecting the surface of precision parts such as semiconductor wafers and optical glass filters.

Comparative Example 5 A laminated composite rubber film of Comparative Example 5 was produced in the same manner as in Example 3, except that the polymethylpentene film of Comparative Example 1 was used as the cover film. The average surface roughness (Ra) of the rubber film surface is 0.5
The rubber film / article film had a low tensile shear adhesive strength of 0.1 N / cm ² or less, and lacked practicality.

Comparative Example 6 A laminated composite rubber film of Comparative Example 6 was produced in the same manner as in Example 3, except that the addition of trimethylolpropane trimethacrylate was omitted. The delamination strength of the obtained composite rubber film is 0.1 N / 20.
mm, which was inferior in practicality.

Example 4 In Example 3, the silicone rubber compound was changed to a rubber having a hardness of 20 degrees, the adhesion improver was changed to pentaerythritol tetraacrylate, the addition amount of the adhesion improver was changed to 3 parts, and the rubber thickness was changed. An uncrosslinked composite rubber film with a cover film was laminated in the same manner as in Example 3 except that each (after drying) was changed to 150 μm. This laminate was introduced into an electron beam irradiation device, and 20 mm from the substrate film side.
After irradiating with an electron beam of 0 KV and 15 Mrad, and then peeling off the cover film, it was again introduced into the electron beam irradiation device,
The film was irradiated with an electron beam of 200 KV and 10 Mrad from the rubber film side and wound up in a roll.

In the obtained composite rubber film for bonding, the rubber film / substrate film had a delamination strength of 10 N / 20 mm or more because the rubber film was damaged during the measurement. Also, the average surface roughness (Ra) of the rubber film
Was 0.025 μm, the tensile shear adhesive strength of the rubber film / article film was as high as 10 N / cm ² , and the peel adhesive strength was as low as 0.1 N / 20 mm.
The composite rubber film to be adhered was suitable for temporary fixing at the time of surface processing of an optical glass filter.

Example 5 An uncrosslinked rubber film (thickness after drying: 50 μm) and a non-crosslinked rubber film were formed on the base film surface of the composite rubber film with a cover film obtained by laminating and crosslinking in Example 3 in the same manner as in Example 3. The cover film was laminated, and the laminate was introduced into an electron beam irradiation device, irradiated with an electron beam of 250 KV and 15 Mrad from the cover film side on the uncrosslinked rubber film, and wound into a roll. The obtained rubber film has an adhesive function on both sides.For example, when used as a sheet for temporarily fixing the disk when printing on a compact disk, the adhesive tape is not required for fixing to a printing machine. It is more suitable for fixing than the composite rubber film to be attached of Example 3.

[0058]

According to the first aspect of the present invention, since the rubber film has a smooth surface, the rubber film has excellent adhesion to an article having a smooth surface and can strongly fix the article. In addition, since it does not have an adhesive layer, the adhesive does not transfer to the article when the article after fixing is peeled off and does not stain the article surface, and is also combined with a polyester base film,
It is excellent in handleability and workability, and is excellent in cushioning property due to the elasticity of the rubber film, and excellent in protection of the article surface. Therefore, it can be used in a wide range of industrial fields as a sheet or tape for temporarily fixing an article and for covering and protecting the article surface.

In particular, according to the second aspect of the present invention, it is possible to increase the delamination strength between the rubber film and the base film to make the base film more difficult to peel. Claim 3
In the invention described in (1), since the interlayer peel strength of the rubber film / base film is limited by a numerical value, the production becomes easy. According to the fourth aspect of the invention, it is easy to set the average surface roughness of the rubber film surface, and it is effective for protecting the rubber film surface. In the invention according to claim 5, since the interlayer peel strength of the rubber film / cover film is lower than that between the rubber film and the base film and is limited by a numerical value, the production becomes easier, and Separation from the article becomes easier.

According to the invention of claim 6, according to claim 1,
5 can be easily and economically produced. In particular, according to the invention described in claim 7, the average surface roughness (Ra) of the rubber film can be easily set to a predetermined size, and the surface of the rubber film can be easily protected.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29L 9:00

Claims (7)

[Claims] 1. A composite rubber film obtained by laminating a rubber film on at least one surface of a base film made of polyester, wherein the surface of the rubber film is formed as an adhesive surface having an average surface roughness (Ra) of 0.12 μm or less. A composite rubber film for sticking, characterized in that: 2. The sticking composite rubber film according to claim 1, wherein the rubber film comprises a rubber composition containing an adhesion improver. 3. The composite rubber film according to claim 1, wherein the rubber film / base film has an interlayer peel strength of 5 N / 20 mm or more. 4. The sticking composite rubber film according to claim 1, wherein a cover film is releasably laminated on the surface of the rubber film. 5. The composite rubber film according to claim 4, wherein the rubber film / cover film has an interlayer peel strength of 4 N / 20 mm or less. 6. A method for producing a composite rubber film comprising laminating an uncrosslinked rubber composition containing an adhesion improving agent on at least one side of a base film made of polyester, and then laminating the rubber composition. A method for producing a composite rubber film for sticking, characterized in that the surface of the rubber film obtained as described above is formed on an adhesive surface having an average surface roughness (Ra) of 0.12 μm or less. 7. The composite rubber according to claim 6, wherein a cover film having an average surface roughness (Ra) of 0.12 μm or less is laminated on the surface of the uncrosslinked rubber film, and the cover film is peeled off before or after the crosslinking treatment. Film manufacturing method.