JPH07100743B2 - Adhesive silicone rubber sponge gasket - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive silicone rubber sponge gasket, and more particularly to an adhesive silicone rubber sponge gasket which can be adhered to a concrete panel or the like using a chloroprene adhesive.

[0002]

2. Description of the Related Art Conventionally, a method of attaching a chloroprene-based gasket with a chloroprene-based adhesive has been used to attach the gasket to a building exterior material (hereinafter abbreviated as PC panel). Since gaskets are required to have fire resistance and heat resistance, silicone rubber sponge gaskets have been used for this purpose.

However, since this silicone rubber sponge gasket cannot be bonded with a chloroprene adhesive, a two-color extruded gasket made of silicone-modified EPDM is used for this bonding portion, or a method of bonding with a silicone rubber adhesive, Alternatively, a method has been adopted in which the skin layer of the silicone rubber sponge gasket is removed and the cell layer surface is permeated with a chloroprene-based adhesive to adhere with a physical anchor effect.

[0004]

[Problems to be Solved by the Invention]
The color extruded sponge gasket has a problem that the production process is complicated and the productivity is inferior.In the method using the silicone rubber adhesive, the gasket is peeled by its own weight because the silicone rubber adhesive is not sticky. Therefore, there is a drawback in that it is necessary to temporarily fix the tape until the gasket is completely adhered, and an extra step of temporary fixing is required. Further, the method of permeating the chloroprene adhesive into the cell layer has a problem that the chloroprene adhesive does not sufficiently permeate depending on the foaming state of the silicone rubber sponge, the adhesive strength is not stable, and there are many variations. is there.

[0005]

The present invention relates to an adhesive silicone rubber sponge gasket which solves the above drawbacks and problems, in which the silicone rubber sponge cell surface excluding the skin layer has a silane coupling agent. And then the surface is coated with a chloroprene adhesive.

That is, the present inventors have conducted various studies to develop a silicone rubber sponge gasket capable of adhering to a PC panel or the like. As a result, regarding this, a chloroprene adhesive is adhered to a silicone rubber sponge gasket from which a skin layer has been removed according to a known method. It penetrates the agent,
Before the treatment with the chloroprene adhesive, the cell surface of the silicone rubber sponge excluding the skin layer is treated with the silane coupling agent in advance, so that the filler and the silane coupling agent contained in the silicone rubber are separated. Since the chloroprene adhesive adheres to the organic group part of this silane coupling agent, the silicone rubber sponge gasket and the chloroprene adhesive bond firmly, and since the silane coupling agent is attached, the chloroprene adhesive It has been found that the silicone rubber sponge gasket thus produced can be easily bonded to a PC panel or the like with this chloroprene adhesive, and the present invention has been completed. It was This will be described in more detail below.

[0007]

The present invention relates to an adhesive silicone rubber sponge gasket, which is obtained by treating the silicone rubber sponge cell surface excluding the skin layer with a silane coupling agent and then coating the surface with a chloroprene adhesive. This is because the chloroprene adhesive adheres to the silane coupling agent, and therefore the silicone rubber sponge gasket and the chloroprene adhesive firmly adhere to each other, so this product can be easily applied to PC panels, etc. The advantage is given that it can be glued.

The adhesive silicone rubber sponge gasket of the present invention is a silicone rubber sponge gasket provided with a chloroprene adhesive layer. This silicone rubber sponge gasket is made of a foam of silicone rubber, which average unit formula R _a S i O
_{(4-a) / 2} , wherein R is an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, an alkenyl group such as a vinyl group or an allyl group, an aryl group such as a phenyl group or a tolyl group, Or an unsubstituted or substituted monovalent selected from a chloromethyl group, a trifluoropropyl group, a cyanoethyl group, etc., in which some or all of the hydrogen atoms bonded to these carbon atoms are substituted with a halogen atom, a cyano group, etc. An organopolysiloxane having a hydrocarbon group and a of 1.8 to 2.1, preferably 80 mol% of which is a methyl group, and 0.1 to 0.5 mol% of which is a vinyl group, 25 It is made of methylvinylsiloxane having a viscosity at 100C of 100 cS or more, preferably 1,000 cS or more.

The organopolysiloxane contains a filler,
A silicone rubber sponge compound for forming a silicone rubber sponge gasket by blending a cross-linking agent and a foaming agent is used, and the filler used here is fumed silica, wet silica, quartz powder, diatomaceous earth, etc. It is sufficient to add 20 to 200 parts by weight of particles having a particle size of 50 μm or less to 100 parts by weight of organopolysiloxane. In addition to the silica, a silane or siloxane containing an alkoxy group, a silanol group or the like may be added as a silica dispersant.

The cross-linking agent used here is for curing the silicone rubber composition, which includes benzoyl peroxide, 1,1-ditertiary butyl peroxy-3,3,5-. Trimethylcyclohexane, 2,5-dimethyl-2,5-dibenzoylperoxyhexane, 1,6-bisterly butyl carboxyhexane, dicumyl peroxide, 2,5-dimethyl-2,5-ditertiary butyl hexane, etc. For example, these are added in an amount of 1 to 5 parts by weight based on 100 parts by weight of the organopolysiloxane. This is because the above-mentioned organopolysiloxane contains an alkenyl group, and it is added to the molecule serving as a crosslinking agent. Organohydrogenpolysiloxane having at least two hydrogen atoms bonded to elementary atoms and addition reaction An addition reaction type silicone rubber composition to which a platinum catalyst (chloroplatinic acid, chloroplatinic acid and an alcohol, aldehyde, olefin, vinylsiloxane complex salt, etc.) as a reaction catalyst is added may be used.

As the foaming agent used here, azo type azodicarbonamide, azobisisobutyronitrile, nitroso type N, N'-dimethyl-N, N'-dinitrosoterephthalamide, N, An organic foaming agent that decomposes to generate nitrogen gas, such as N'-dinitrosopentamethylenetetramine, is preferable. This type may be selected from the decomposition temperature, the amount of generated gas, etc., but this amount is necessary. According to the expansion ratio of the sponge, the amount may be 1 to 10 parts by weight with respect to 100 parts by weight of the organopolysiloxane.

The silicone rubber compound for producing the silicone rubber sponge thus produced is extruded into a gasket shape from an extruder, put in a horizontal or vertical vulcanization furnace, and heated to foam and cure. Then, the silicone rubber sponge gasket is made, but since this sponge gasket is made of silicone rubber and cannot be adhered to the PC panel as it is, a chloroprene adhesive is adhered to it.

In the present invention, a chloroprene adhesive is adhered to the silicone rubber sponge gasket. In the present invention, first, the skin layer of the silicone rubber sponge is removed and the sponge cell surface is treated with a silane coupling agent. To be done. When treated in this way, the filler contained in the silicone rubber compound appears on the cell surface of the silicone rubber sponge gasket that appears when the skin layer is removed. The coupling agent and the filler are reactively bonded, and the organic group of the silane coupling agent is retained in the cell layer.

The treatment with the silane coupling agent may be carried out by applying the silane coupling agent to the cell surface of a silicone rubber sponge and then drying the sponge. The silane coupling agent used here is a known commercially available product. And thus examples are aminosilanes, epoxysilanes, mercaptosilanes and the like. In this treatment, a primer blended with a silicone rubber base, a silica type filler and the like may be used together with the silane coupling agent.

The adhesive silicone rubber sponge body of the present invention is obtained by coating the surface of the silicone rubber sponge gasket treated with the silane coupling agent with a chloroprene adhesive. As described above, the organic group of the silane coupling agent is held on the agent-treated surface, so if the chloroprene adhesive is coated here, the chloroprene adhesive firmly adheres to the silicone rubber sponge gasket, and The coupled coupling agent facilitates the permeation of the chloroprene adhesive, and also provides a strong anchoring effect, resulting in a stronger bond, and this chloroprene adhesive makes it easier to adhere to the PC panel. Advantages are given.

[0016]

EXAMPLES Next, examples and comparative examples of the present invention will be described. Examples, Comparative Examples Silicone rubber sponge compound KE1725U [trade name of Shin-Etsu Chemical Co., Ltd.] having a foaming ratio of 3 times is extruded into a gasket shape having a bottom surface of 15 mm x width of 17 mm x height of 25 mm using an extruder. In a horizontal vulcanization furnace, it was heated to 300 ℃ and foamed and cured to form a silicone rubber sponge gasket with a bottom surface of 23 mm × width of 31 mm × height of 42 mm.

Then, the skin layer 2 mm on the bottom surface of the silicone rubber sponge gasket was removed with a dedicated slicer, and the silane coupling agent shown in Table 1 was applied to the cell surface excluding the skin layer at a rate of 100 g / m ² and dried. After that, a chloroprene adhesive was applied to this surface at a rate of 200 g / m ² to make a silicone rubber sponge gasket to which the chloroprene adhesive was adhered. Next, apply a chloroprene adhesive of 200 g / m ² to the surface of a concrete plate of 250 × 250 × 50 mm, and join the chloroprene adhesive applied surface of the silicone rubber sponge gasket obtained above to this chloroprene adhesive applied surface. After one day, the adhesive strength was measured by peeling at 90 °, and the results shown in Table 1 were obtained.

However, for comparison, the same silane coupling agent as described above was used instead of the above silane coupling agent, and the same treatment as in Example was carried out. The results are as shown in the above.

[0019]

[Table 1]

[0020]

The present invention relates to an adhesive silicone rubber sponge gasket, which is prepared by treating the silicone rubber sponge cell surface excluding the skin layer with a silane coupling agent as described above, and then adhering this surface to chloroprene. It is characterized by being coated with an agent,
Since the chloroprene adhesive is firmly adhered to the silicone rubber sponge cell surface, it has an advantage that it can be easily adhered to a PC panel or the like.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroyoshi Arima 300--5 Toyohara, Motohara, Kamigawa-cho, Kodama-gun, Saitama Shin-Etsu Polymer Co., Ltd. Kodama Factory (56) Reference JP-A-61-233025 (JP, Sho A) JP-A-5-280105 (JP, A)

Claims (1)

[Claims] 1. An adhesive silicone rubber sponge gasket, characterized in that the silicone rubber sponge cell surface excluding the skin layer is treated with a silane coupling agent, and then this surface is coated with a chloroprene adhesive.