JP3637118B2 - Non-adhesive rubber molded product and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement in a rubber molded product having a low hardness and rich sealing properties.
[0002]
[Prior art]
Rubber molded products that control fluids must have sufficient sealing properties and sharp operating sensitivity, so it is generally necessary to use soft rubber molded products with low hardness, but soft rubber has adhesive properties, so rubber compounding components Attempts have been made to devise the above, or to form a fluororesin film on the surface of a rubber molded product.
However, with such a method, the mechanical strength and solvent resistance of the rubber are lowered, and there are problems such as insufficient adhesion when the fluororesin is laminated, and the sealing property of the rubber molded product is low. It was difficult to achieve both tackiness.
[0003]
[Problems to be solved by the invention]
An object of the present invention is to make a soft rubber molded article non-adhesive without impairing its mechanical properties, solvent resistance, etc., and can be used as a fluid control member with good sealing properties.
[0004]
[Means for Solving the Problems]
In the present invention, the above problem is solved by forming an amorphous quartz film in which polyfluorinated olefin particles are dispersed on the surface of a soft rubber molded product.
[0005]
That is, the product of the present invention is a synthetic rubber molded product having a rubber hardness of 90 degrees or less according to JIS-K6301, and has an amorphous quartz film having polyfluorinated olefin particles dispersed on its surface with a thickness of 5 μm or less. It is characterized by.
[0006]
In this product, polyperhydrosilazane in which polyfluorinated olefin particles are dispersed is applied to the surface of a synthetic rubber molded article having a rubber hardness of 90 degrees or less according to JIS-K6301, and then 80 ° C to 180 ° C, preferably 130 to It is obtained by heating to 150 ° C. and forming an amorphous quartz film having polyfluorinated olefin particles dispersed on the surface to a thickness of 5 μm or less .
[0007]
The amorphous quartz film is preferably formed to a thickness of 0.5 to 3 μm, and the polyfluorinated olefin particles dispersed in the quartz film are particles of polyfluorinated ethylene having a particle diameter of 0.3 to 5 μm. Is preferably used. In general, the polyfluorinated olefin particles are preferably used at a ratio of about 10 to 30% by weight with respect to the quartz film.
[0008]
Further, as the rubber used in the rubber molded product of the present invention, for example, fluorine rubber, fluorosilicone, nitrile rubber, butyl rubber, ethylene propylene rubber and the like are effective.
[0009]
Furthermore, in order to form the amorphous quartz thin film of the present invention, it is preferable to use a 1 to 3% solution of polyperhydrosilazane having a molecular weight of 600 to 1500, and the solvent is polar such as xylene, cyclohexane or cyclohexene. Organic solvents are suitable.
[0010]
Such rubber molded article obtained in the present invention, the silica film formed on the surface, as well as blocking the adhesive extracts contained in the rubber, the poly fluorinated olefin particles present on the surface, stable, non-tacky give In addition, it has good sealing properties as a rubber molded product, and heat resistance and gasoline resistance are improved. As will be shown later in the examples, it does not stick, operates lightly, and has a remarkable mechanical resistance during steady operation. Improved.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in more detail with reference to the following examples.
Example 1
The product shown in FIG. 1 is a needle valve that supplies an appropriate amount of fuel required for the engine, but this valve is required to operate accurately to keep the gasoline oil level constant.
First, the tip of the valve seat body, which is a brass product, is a fluororubber (FN903, manufactured by Fujikura Rubber) molded product with a rubber hardness of 90 degrees 2—the tip diameter is 10 mm, the bottom diameter is 35.4 mm, and the thickness is The valve seat 1 equipped with a substantially conical molded product of 10 mm was immersed in xylene and degreased and washed.
Next, a solution obtained by dispersing polyfluorinated ethylene having a particle size of 0.3 to 2 μm in a 20% xylene solution of polyperhydrosilazane having a molecular weight of 900 (Tonen polysilazane PHPS-2) in a ratio of 20% by weight of the solid content , A coating solution was prepared by diluting with 10 times the amount of xylene.
After immersing the valve seat 1 fitted with the rubber molded product 2 degreased and washed as described above in this coating solution, the excess coating solution is shaken off with a centrifuge, heated to 80 ° C. to remove the solvent, and then further 150 The amorphous quartz film 3 was formed on the surface of the rubber molded product 2 by heating at 0 ° C. for 30 minutes.
[0012]
The results obtained and the surface of the product was measured under a microscope, dispersed high-purity amorphous silica film 0.6μm was poly fluoride ethylene particles were found to be in close contact.
Next, the adhesiveness of the rubber molded product 2 of the valve seat 1 coated with the quartz film and the rubber molded product of the uncoated valve seat was measured by the following method.
Each operating characteristic is measured in accordance with the procedure of FIGS. 2A to 2C. First, as shown in FIG. 2A, the valve seat 4 is put on the valve seat 1, and a load 5 of 13.5 g is placed on B. In this state, gasoline was dropped on the valve seat 4 and then left at room temperature of 20 ° C. for 15 hours, then heated in a constant temperature bath at 80 ° C. for 8 hours, and further left at 20 ° C. for 2 hours. In order to measure the adherence between the seat 1 and the valve seat 4, air pressure is applied from the inlet of the valve seat 4 and the pressure at the time of separation is measured.
[0013]
The peeling pressure between the uncoated valve seat 1 and the valve seat 4 is 0.062 to 0.044 kg / m ² (n = 20), whereas the peeling pressure when the coating of the present invention is applied is 0.012 to 0.012. It was found to be very low as 0.018 kg / m ² (n = 20), and the non-tackiness had a remarkable effect.
[0014]
Example 2
The valve seat integrated diaphragm shown in FIG. 3 was molded with hydrogenated nitrile rubber having a rubber hardness of 60 degrees (NEN605 manufactured by Fujikura Rubber), degreased and washed with cyclohexene.
Next, a liquid obtained by dispersing polyfluorinated ethylene powder having a particle size of 0.3 to 2 μm in a 20% cyclohexene solution of molecular weight 800 polyperhydrosilazane (Tonen polysilazane PHPS-1) at a solid content weight ratio of 15%, Further, a coating solution was prepared by diluting with 10 times the amount of cyclohexene.
A coating liquid was sprayed onto the valve seat 4 of the diaphragm that had been degreased and washed, and heated at 80 ° C. for 10 minutes and further at 140 ° C. for 30 minutes to form an amorphous quartz film 3. The quartz film 3 was provided in a ring shape on the back surface of the valve seat 4 at the portion that contacts the valve seat 1.
The coated diaphragm and the uncoated diaphragm thus obtained were respectively incorporated in a flow rate controller 6 molded with 66 nylon resin as shown in FIG. 3 and 4, reference numeral 7 denotes a spring guide portion, 8 denotes an operation membrane portion, 9 denotes a case mounting seal portion, and 1 in FIG. 4 denotes a valve seat, and 10 denotes a spring. 4A shows a state in which the valve is closed, and B shows an open state.
[0015]
A normal uncoated diaphragm was opened at a pressure of 200 mmaq when the water temperature was 25 ° C. However, when the water temperature was raised to 60 ° C., it was first operated at a pressure of 300 mmaq due to diaphragm adhesion.
However, when the diaphragm coated according to the present invention is mounted, the pressure is 100 mmaq when the water temperature is 25 ° C., and the pressure does not change even when the water temperature is raised to 60 ° C. It didn't change.
[0016]
【The invention's effect】
Rubber molded articles obtained by the present invention, the silica film formed on the surface, as well as blocking the adhesive extracts contained in the rubber, the poly fluorinated olefin particles present on the surface, a stable non-adhesive property can be obtained In addition, because it has good sealing properties as a rubber molded product, and heat resistance and gasoline resistance are also improved, it is possible to apply a low-hardness rubber molded product with excellent sealing properties to the valve seat and valve seat of the valve, and it can be firmly fixed. It is possible to obtain a valve that does not occur, operates lightly, and has a significantly improved mechanical resistance during steady operation.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a valve seat in an example of the present invention.
FIG. 2 is an explanatory view of a method for testing the adhesiveness of a rubber molded product of the valve seat of FIG. 1;
FIG. 3 is a cross-sectional view of a diaphragm according to an example of the present invention.
4 is an explanatory diagram of a test method for the diaphragm of FIG. 3. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Valve seat 2 Rubber molded product 3 Quartz membrane 4 Valve seat 5 Load 6 Flow controller 7 Spring guide part 8 Actuation film part 9 Sealing part 10 for case attachment Spring

Claims (5)

A non-adhesive rubber molded product having an amorphous quartz film in which polyfluorinated olefin particles are dispersed with a thickness of 5 μm or less on the surface of a synthetic rubber molded product having a rubber hardness of 90 degrees or less according to JIS-K6301 . To JIS-K6301 synthetic rubber molded surface rubber hardness of 90 degrees or less by, coated with poly-perhydro silazane dispersed polyfluorinated olefins particles, followed by heating to 80 ° C. to 180 ° C., polyvinylidene olefin particles to the surface method for producing a non-tacky rubber molded article and forming the amorphous silica film thickness of less than 5μm were dispersed. 3. The polyfluorinated olefin particles are particles of polyfluorinated ethylene having a particle size of 0.3 to 5 [mu] m, and are used at a ratio of 10 to 30% by weight with respect to the quartz film. the method of.   The method according to claim 2 or 3, wherein the polyperhydrosilazane has a molecular weight of 600 to 1,000.   The method according to any one of claims 2 to 4, wherein the rubber is fluorine rubber, fluorosilicone, nitrile rubber, butyl rubber or ethylene propylene rubber.

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