JPH0626863B2 - Method for producing silicone rubber connector having sponge-like support material - Google Patents

Description

TECHNICAL FIELD The present application relates to a method for producing a silicone rubber connector having a sponge-like foamed rubber plate as a support material.

[Prior Art] Conventionally, in the production of a silicone rubber connector having a sponge-like support material, when thermoforming this sponge-like support material, as shown in FIG.
Spacer 6 with the same dimensions as the product dimensions required after molding
Was inserted, heated and foamed to be molded.

However, in this method, since the heating start time difference and unevenness occur in the heat supply to the support material to be molded, the eccentricity of the core material 2 as shown in FIG. 3 (biased to the upper mold side)
The corrugation of the core material 2 is likely to occur, and molding of a material having a thickness of 2 to 3 mm or more could not be carried out once.

[Problems to be Solved by the Invention] The present application has been made to solve the above-mentioned problems of the prior art and to provide a silicone rubber connector having a sponge-like support material without eccentricity or waviness of the core material. .

[Means for Solving the Problems] The present application is to solve the above-mentioned problems, and a gist of the method for manufacturing a silicone rubber connector is that a floating mold is used for thermoforming a sponge-like support material. To do.

The present application will be described in detail below.

In the present application, the core material sandwiched between the support material materials is thermoformed using a floating mold. By using this mold, the mold is brought into close contact with the material from the initial heating, and the upper and lower support material materials are used. The time difference between the start of heating and the uneven heating are eliminated, and the foaming force of the support material material caused by heating allows the material to be thermoformed to the required thickness dimension while the die is in close contact with the material.

At this time, the gas generated by decomposition of the foaming agent mixed into the support material is used to foam into a sponge shape, but the expansion force due to foaming is adjusted to be larger than the load of the floating mold and the mold is pushed up. The load of the mold is preferably 15 gf / cm ² or less, and most preferably around 6 gf / cm ² .

The support material may be made of silicone rubber, which allows sufficient bonding with the core during thermoforming.

[Examples] Examples of the present application will be described below.

Based on silicone rubber compound KE151KU (trade name of Shin-Etsu Chemical Co., Ltd.), a foaming agent SO paste (trade name of Shin-Etsu Polymer Co., Ltd.) and vulcanizing agents C-1 and C
-3M (both trade names manufactured by Shin-Etsu Chemical Co., Ltd.) is kneaded as a support material 1 ', and is dispensed to a predetermined thickness on a polyethylene terephthalate film 7 having a thickness of 100 μm. The core material 2
As a sandwich. The thickness W'of this sandwich was set to be 1.5 to 1.7 times the thickness W when molded and foamed. (See FIG. 4) This was inserted into a hydraulic bench press (manufactured by Koei Seisakusho) with an electric mechanical stopper equipped with a floating mold 3 having a thickness dimension W set in advance and heated to about 170 ° C. to perform thermoforming. At this time, the above set value is obtained at the end point where the floating mold 3 is pushed up by the heat foaming. (Refer to FIG. 1) In the above thermoforming, foaming is performed for about 15 seconds after the start of heating / pressurization, but for the vulcanization of the support material 1, after that, heating / pressurization is continued for about 75 seconds as it is to complete the molding. did.

In the thermoforming, the pressure applied by the hydraulic bench press (clamping force) was maintained at about 11.5 kgf / cm ² .

The silicone rubber connector having the sponge-like support material thus obtained had no eccentricity or waviness of the core material.

[Effects of the Invention] As is apparent from the above description, by the molding method using the floating mold of the present application, the eccentricity of the core material in which the lower side of the support material is generated earlier than the upper side is foamed,
The corrugation of the core material due to local heat unevenness was prevented, and it became possible to mold even those having a thickness of 2 to 3 mm or more, which could not be molded by one time in the past. Not only that, the heat transfer time was shortened and the vulcanization speed was accelerated by the close contact of the mold.

Furthermore, by introducing a floating mold, the conventional spacers can be removed, and by attaching an electric mechanical stopper to the hydraulic bench press, product thickness dimensions can be easily changed.

[Brief description of drawings]

FIG. 1 is a diagram showing a heating / pressurizing state by a floating mold according to one embodiment of the present application as the heating progresses,
FIG. 2 is a view showing a heating / pressurizing state in the conventional method,
FIG. 3 is a view showing an eccentricity or a wavy state of the core material, and FIG. 4 is a view showing a method of constructing a sandwich-shaped article composed of a support material and a core material in one embodiment of the present application. 1 ... Support material foamed into a sponge 1 '... Support material before foaming (support material) 2 ... Core material 3 ... Floating mold 4 ... Hot plate mounted on hydraulic bench press 5 ... Conventional Hot plate attached to die hydraulic press 6 …… Conventional die spacer 7 …… Polyethylene terephthalate film (100μ
m) 8 ... Lower hot plate

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Claims (1)

[Claims] 1. A method for producing a silicone rubber connector, wherein a floating mold is used for thermoforming a sponge-like support material.