JPS60152584A - Rubber o-ring - Google Patents

Abstract

PURPOSE:To provide a low-cost and highly chemical resistant O-ring made of rubber, prepd. by surface coating a base O-ring with a corrosion-resistant fluorine-contg. polymer by high-frequency sputtering. CONSTITUTION:A coating film of about 1-10mu is formed on the surface of an O-ring made of industrical rubber such as fluorine rubber by high-frequency sputtering of a corrosion-resistant fluorine-contg. polymer (e.g. polytetrafluoroethylene or polyvinylidene fluoride). The resultant O-ring has excellent resistance to chemicals, flexural property, adhesion and durability and is suitable for mechanical seal of a pump for chemicals, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to rubber O-rings. More specifically, the present invention relates to a rubber O-ring having a coating on its surface.

Submerged pumps are often used in chemical tankers, chemical plants, etc., and because these pumps require mechanical seals, O-links are built into them. However, when this pump is used for aromatic hydrocarbons such as benzene, toluene, and xylene, ordinary rubber materials can cause problems such as swelling instantaneously, making it difficult to use them for long periods of time or repeatedly. It was impossible to do so. Furthermore, recently, rubber materials with excellent chemical resistance have been developed, but these are generally very expensive and cannot be used as general-purpose materials.

However, the inventors have discovered that by corrugating the surface of a rubber O-ring with a high-frequency sputtering coating of a corrosion-resistant fluorine-containing polymer, a rubber 1ilQ ring with good chemical resistance can be obtained at low cost. . Therefore, the present invention
The present invention relates to such a surface-broken rubber O-ring.

The surface-coated O-ring is molded from an industrial rubber material such as fluororubber, and its surface is coated with a sputtering film (film) of a corrosion-resistant fluorine-containing polymer such as polytetrafluoroethylene, borif, vinylidene fluoride, etc.

The coating is performed by radio frequency sputtering, and a schematic diagram of one embodiment of the process is shown in FIG.

Rlj, in a reactor 1 equipped with a vacuum (not shown),
Upper electrode 2 and lower electrode #i+3 located opposite each other
were installed, and the upper electrode was fitted with a disc-shaped fluorocarbon-containing combined molded product target 4, which was machined with mounting screws, etc., and the lower electrode was made of 0'J made from fluorocarbon A, which had been degreased with methanol, etc. Equipped with a 5.5' engine.

In the sputtering process, first use a vacuum pump (not shown) such as an oil diffusion pump to exhaust the air in the reactor through the exhaust port 6.
Then, reduce the pressure to the order of 10-5 Torr, then adjust the barrier pull leak valve 7. Open the pressure adjustment valve 8 from step C, and add argon or other inert gas from the cylinder 9. Adding bongas etc. to the reactor,
The pressure there is on the order of 10-3 Torr. Here, the main valve (not shown) of the exhaust stack is adjusted to bring the pressure to A-der of 10-2 Torr. In addition, the code|symbol 10 is a pressure gauge.

The sputtering operation is performed using a high frequency power source (i3.56MHz
) 11i and the barrier pull capacitor 12. First, under the above argon pressure, the surface of the O-ring is subjected to high-frequency sputter edging for about 3 minutes with an effective power of about 50 W. After cleaning, high-frequency sputtering was performed at an effective power of about 200 W for about 30 minutes, and the surface of the O-ring was sputtered to a Tt of 101 rms in order to prevent pinholes from forming on the O-ring surface and from the viewpoint of durability (flexibility and adhesion). Generally, when a film with a thickness of about 5 μm is obtained, the discharge is stopped, the introduction of argon gas, etc. is stopped, the main valve is closed, the process is temporarily stopped, and then the treated surface of the O-ring is Perform the same process on the opposite side.

In order to confirm the chemical resistance effect of the thus treated O-IJ, the surface of which was coated with a polytetrafluoroethylene sputtering film with a film thickness of 5 μm, it was added to toluene at room temperature (26-30°C). We conducted an immersion test of
The weight increase rate due to Akijun was measured. The results obtained are shown in the following table.

Immersion time (min) Untreated 0 ring Surface wave No. 5 +0.10% 0 10 +0.12% 0 100 +0.62% +0.07% 5(1(1+1.60% +(1,25%) 1000+
2.38% +0.74%5000' +5.0%
As can be seen from the results of +1.65% or more, the O l surface was coated with a high-frequency sputtering film that was different in composition and chemical application from the corrosion-resistant fluorinated polymer used as the sputtering material. ) ring has good chemical resistance, showing only about % less swelling than the fluororubber O-ring used in various parts due to its excellent chemical resistance. Even though the coating is thin, it has good adhesion because it is a high-frequency sputtering coating, and it has excellent bending resistance and durability.

Figure 1 is a schematic diagram of the high-frequency temporary sputtering method applied in the present invention.

(Explanation of symbols) 1... Reactor 2... Upper electrode 3... Lower electrode 4... Fluorine-containing cable car combination target 5...
・Rubber O-ring 9...Inert gas cylinder 11...High frequency type nri 1 12...Pariabu A condenser representative reception [Shiko [IXI Wa lost]

Claims (1)

[Scope of Claims] A rubber O-ring whose surface is coated with a high-frequency snow-cutter nong film-C made of a tiUV edible fluorine-containing polymer. 2. Patent curved water in which the corrosion-resistant fluorine-containing main body combination is polytetrafluoroethylene.
0 link made by Mu. 3. A rubber O-ring according to claim 1 or 2, the surface of which is coated with a coating having a thickness of about 1 to 10 μm.