JPH0470331A - Manufacture of silicone rubber material having sticking layer - Google Patents

Abstract

PURPOSE:To obtain an inexpensive silicone rubber material by strongly bonding a double-side sticking tape to the surface of the silicone rubber material by applying a silane coupling agent solution to the surface of the silicone rubber material and bonding the double-side sticking tape to the coated surface thereof when the coated surface is in a wet state and subsequently drying the coated surface to bond the double- side sticking tape to the surface of the silicone rubber material. CONSTITUTION:First, a silane coupling agent solution is applied to the surface of a silicone rubber material and, next, a double-side sticking tape is bonded to the coated surface thereof before the coating solution containing the silane coupling agent is dried. When the coating solution containing the silane coupling agent is made uniform, it is diffused and simultaneously becomes easy to penetrate in the sticking layer of the tape and bonding strength is enhanced. Finally, the whole is dried to integrally bond the silicone rubber material and the double-side sticking tape. As the double-side sticking, one containing an acrylic sticking agent is used and, as the silane coupling agent, N- (aminoethyl) -aminopropyltrimethoxysilane is used to obtain the silicone rubber material low in manufacturing cost and having a surface sticking layer increased in bonding strength.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for producing a silicone rubber material having an adhesive layer on its surface.

[Prior Art] A silicone rubber material having an adhesive layer on its surface is useful, for example, as a temporary bonding means for a silicone rubber connector or as a bonding means for a silicone rubber foam. These are used in various fields such as electrical/electronic parts and precision machinery.

Conventionally, the silicone rubber material having the above-mentioned surface adhesive layer is
It was manufactured by applying a silicone adhesive to the silicone rubber surface. The reason for this is that the silicone rubber surface has few active groups and is difficult to adhere to, so it was necessary to improve the adhesive strength or integrate it with the silicone rubber material using a silicone adhesive, which is a homogeneous material.

Another known example is an invention in which acryloxyalkylsilane is mixed into silicone rubber, molded into a desired shape while in contact with the surface of a substrate, and bonded to the surface of the substrate by heating and vulcanization. -24457).

Another known example is an invention in which a silane compound is applied to one side of a silicone rubber sheet, heat treated, and then the silane compound coated sides of the silicone rubber sheet are bonded together with an adhesive (particularly Kosho 61-3686
Publication No. 5). Furthermore, as another known example, it has been proposed to apply a silane coupling agent to the surface of silicone rubber, and after drying, apply a double-sided adhesive (JP-A-61-2
Publication No. 33025).

[Problems to be Solved by the Invention] However, in the conventional technology, a silicone adhesive is applied as an adhesive, and the silicone adhesive is expensive, making it impossible to reduce the overall manufacturing cost. There was an issue.

In addition, even if a normal adhesive, such as an adhesive based on an acrylic ester polymer, is applied directly to a silicone rubber material, the silicone rubber surface has few active groups (and is difficult to adhere to, so the adhesive peels off immediately). There was an issue of doing so.

Also, JP-A No. 61-233025 and JP-A No. 61-233025,
The method disclosed in Publication No. 36865 had a problem in that the adhesive strength between the silicone rubber and the double-sided adhesive was not very high.

In order to solve the problems of the prior art, the present invention firmly adheres a double-sided adhesive tape to the surface of a silicone rubber material,
It is an object of the present invention to provide a method for manufacturing a silicone rubber material having an adhesive layer at low cost.

[Means for Solving the Problems] In order to achieve the above object, the method for manufacturing a silicone rubber material having a surface adhesive layer of the present invention is a method for manufacturing a silicone rubber material having a surface adhesive layer, which first comprises: The method is characterized in that a silane coupling agent solution component is applied to the surface of the silicone rubber material, a double-sided adhesive tape is applied when the coated surface is wet, and then the silicone rubber material and the double-sided adhesive tape are bonded by drying.

In the present invention, the double-sided adhesive tape preferably contains an acrylic adhesive, and the silane coupling agent preferably comprises N-β(aminoethyl)γ-aminopropyltrimethoxysilane.

Further, in the present invention, it is preferable that the base material of the double-sided adhesive tape is made of a resin film.

[Function] According to the configuration of the method of the present invention described above, first, the silane coupling agent solution component is applied to the surface of the silicone rubber material. The silane coupling agent solution component may be pure as it is, or may be dissolved or suspended in water. When dissolved or suspended in water, the concentration of the silane coupling agent is preferably about 0.1 to 90% by weight.

Next, while the coating liquid component containing the silane coupling agent is in a wet state, that is, before it dries, a double-sided adhesive tape is applied to the coated surface. When the coating liquid component containing the silane coupling agent is in a wet state, if double-sided adhesive tape is applied to the coating surface,
The coating liquid components containing the silane coupling agent are uniformly diffused and at the same time easily permeate into the interior of the adhesive layer, improving adhesive strength.

Finally, the silicone rubber material and double-sided adhesive tape are bonded and integrated by drying. The key is to apply the double-sided adhesive tape to the surface coated with the silane coupling agent while it is wet.

Further, according to a preferred embodiment of the present invention, a double-sided adhesive tape containing an acrylic adhesive is used, and a silane coupling agent is N-β (aminoethyl) γ-ruaminopropyltrimethoxysilane. A method of manufacturing a silicone rubber material having a surface adhesive layer with low manufacturing cost and high adhesive strength can be provided.

Furthermore, according to a configuration in which a resin film is used as the base material of the double-sided adhesive tape, which is a preferred embodiment of the present invention,
When the silicone rubber material is a foam or something soft and easily stretchable, a reinforcing effect is exhibited and it can be made difficult to stretch and easy to position.

[Example] The present invention will be explained in more detail below using Examples.

First, as the adhesive composition of the double-sided adhesive tape, it is preferable to use one whose main ingredient is an acrylic ester polymer. Adhesives based on acrylic ester polymers have superior weather resistance and heat resistance compared to rubber-based adhesives, require almost no anti-aging agents, are highly transparent, and have excellent oil resistance and adhesive properties. It is. Furthermore, the ester moiety of the polyacrylic acid ester is preferably an ethyl group, a butyl group, a 2-ethylhexyl group, or the like in order to increase flexibility.

Furthermore, acrylic acid, methyl methacrylate, vinyl acetate, etc. can also be copolymerized.

In addition to the main ingredient, the double-sided adhesive tape used in the present invention also contains ester gum, rosin and its derivatives, tackifiers such as coumaron/indene resin, phenol resin, and petroleum resin, and phthalic acid. Plasticizers such as esters (such as DBPSDOP), chlorinated paraffin, diphenyl chloride, castor oil, and low molecular weight polyisobutylene may be added. As the support (substrate), commonly used materials such as cloth, paper, and resin films can be used. Among these, particularly preferred base materials are polyester films, polypropylene films, and the like. This is because when the silicone rubber material is a foam or something soft and easily stretchable, a reinforcing effect is exhibited, and it can be made difficult to stretch and easy to position.

In the above, the silane coupling agent can be represented by the general formula R' Si (OR)3, and has two types of reactive groups: an R+ group and an OR group.

R1 group is an amino group, a mercapto group, a methacryloxy group,
It is an organic reactive group such as a vinyl group or an epoxy group, and easily bonds with the adhesive layer. The OR group represents a hydrolyzable alkoxy group. For example, methoxy group. This alkoxy group (OR group) becomes silanol through hydrolysis, reacts with the silicone rubber material, and easily forms a 5i-0-8i bond. Therefore, the silane coupling agent can firmly adhere the adhesive layer and the silicone rubber material.

Next, in the present invention, the adhesive layer is formed of a double-sided adhesive tape. If double-sided adhesive tape is used, the adhesive layer can be formed to have a uniform thickness, and commercially available double-sided adhesive tapes can be used, so manufacturing costs can be reduced. There is also the advantage that a double-sided adhesive tape having an adhesive with optimal characteristics can be selected depending on the conditions for the other side, the intended use, the object to be bonded, etc.

This will be explained below based on specific experimental examples.

Example 1 N-β(
A silane coupling agent consisting of a solution of (aminoethyl) γ-aminopropyltrimethoxysilane (manufactured by Nippon Unicar) was applied uniformly by spray, and when wet,
Main ingredient is acrylic ester polymer with a width of 25 mm.
A double-sided adhesive tape (manufactured by Nitto Denko Corporation) using a polyester film as a base material was attached. In this state, it was dried at a temperature of 100° C. for 15 minutes, and at the same time it was dried, an adhesive treatment was performed. The adhesive strength between the silicone rubber of the obtained silicone rubber material having an adhesive layer and the double-sided adhesive tape was measured by peeling it off in a 180° direction using a tensile tester. Table 1 shows the adhesive strength when the amount of silane coupling agent applied was changed.

Comparative Example 1 In Example 1, after applying the silane coupling agent, it was dried (air-dried) at room temperature for 30 minutes, and then a double-sided adhesive was attached. Other conditions were the same as in Example 1. Table 1 shows the adhesion strength between the silicone rubber of the obtained silicone rubber material having the adhesive layer and the double-sided adhesive tape.

Note that Comparative Example 1 is a supplementary test to the example disclosed in Japanese Patent Application Laid-Open No. 61-233025.

As is clear from Table 1, the adhesive strength of the examples of the present invention was clearly higher than that of the method of JP-A-61-233025. The reason for this is that the silane coupling agent was applied and the double-sided adhesive tape was attached while it was still wet.

Example 2 N-β (
A silane coupling agent consisting of a solution of γ-aminopropyltrimethoxysilane (manufactured by Nippon Unicar) was sprayed uniformly at a rate of 3 g/m, and when wet, a 20 mm wide acrylic ester was applied. A double-sided adhesive tape (manufactured by Nitto Denko Corporation) containing a polymer as a main ingredient and a polyester film as a base material was attached.

Next, heat treatment (drying) was performed in an oven at a temperature of 100° C. for the time shown in Table 2. Table 2 shows the results of the adhesive strength of the obtained products.

As is clear from Table 2, it is effective to carry out the drying treatment after applying the double-sided adhesive tape.

Example 3 N-β (aminoethyl)γ-aminopropyltrimethoxysilane (Nippon Unicar) was applied to the surface of a silicone rubber foam sponge sheet (manufactured by Fuji Polymer Industries Co., Ltd.) with a thickness of 5 mm, a length of 100 mm, and a width of 25 mm. Spray a silane coupling agent made from a solution of 5 glrd evenly, and when wet, apply it to a width of 20 mm.
A double-sided adhesive tape (manufactured by Nitto Denko Co., Ltd.) containing an acrylic ester polymer as a main ingredient and a polyester film as a base material was attached.

Next, heat treatment (
The adhesive strength of the obtained product was 440 g.

According to this example, the silicone rubber foam sponge sheet is soft and easy to stretch (has no rigidity), but since the base material of the double-sided adhesive tape is made of a resin film, it has a reinforcing effect and is easy to stretch. It was also easy to position.

As explained above, according to the method of the present invention, the adhesive layer and the silicone rubber material are bonded together using a silane coupling agent, and since the adhesive layer is formed of a double-sided adhesive tape, the surface of the silicone rubber material A silicone rubber material having an inexpensive adhesive layer can be obtained by firmly adhering double-sided adhesive tape to the adhesive layer.

[Effects of the Invention] As explained above, according to the method of the present invention, a silane coupling agent solution component is first applied to the surface of a silicone rubber material, and a double-sided adhesive tape is applied to the surface of the silicone rubber material in a wet state, that is, before drying. When applied to a surface, the following effects can be achieved: the coating liquid component containing the silane coupling agent is uniformly diffused, and at the same time, it becomes easier to penetrate into the inside of the adhesive layer, thereby improving the adhesive strength.

Further, according to a preferred embodiment of the present invention, in which a double-sided adhesive tape containing an acrylic adhesive is used and N-β (aminoethyl) γ-aminopropyltrimethoxysilane is used as a silane coupling agent, A method of manufacturing a silicone rubber material having a surface adhesive layer with low manufacturing cost and high adhesive strength can be provided.

Furthermore, according to a configuration in which a resin film is used as the base material of the double-sided adhesive tape, which is a preferred embodiment of the present invention,
When the silicone rubber material is a foam or something soft and easily stretchable, a reinforcing effect is exhibited and it can be made difficult to stretch and easy to position.

Claims (3)

[Claims] (1) A method for manufacturing a silicone rubber material having an adhesive layer on the surface, in which a silane coupling agent solution component is first applied to the surface of the silicone rubber material, and a double-sided adhesive tape is applied when the coated surface is wet. 1. A method for producing a silicone rubber material having a surface adhesive layer, which comprises drying and adhering the silicone rubber material and the double-sided adhesive tape. (2) Production of a silicone rubber material having a surface adhesive layer according to claim 1, wherein the double-sided adhesive tape contains an acrylic adhesive and the silane coupling agent comprises N-β(aminoethyl)γ-aminopropyltrimethoxysilane. Method. (3) The method for producing a silicone rubber material having a surface adhesive layer according to claim 1, wherein the base material of the double-sided adhesive tape is made of a resin film.