JPH11290767A - Water-repellent member and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the water-repellent member capable of easily preventing the deposition of a waterdrop and the production method suitable for the member. SOLUTION: A water-repellent film cosisting of a vinylidene fluoride polymer obtained on the positive electrode side by the plasma polymerization utilizing a glow discharge generated by applying a DC high voltage in vacuum is provided on the surface of a member 1 to be treated. The inside of a vacuum treating chamber is filled with a vinylindene fluoride monomer gas under vacuum, a DC high voltage is applied on the reticular electrode provided directly above the number 1 prepared in the vacuum treating chamber to generate a glow discharge, and the monomers are plasma-polymerized. Otherwise, a positive DC high voltage is directly applied on the member 1 itself or on the electrode holding the member to generate a glow discharge to polymerize the monomers, and the water-repellent plasma-polymerized film 2 is formed on the member 1 surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-repellent member having improved water repellency of members which cause inconveniences such as generation of mold due to dew condensation or water, insulation breakdown, etc. It relates to the manufacturing method.

[0002]

2. Description of the Related Art Heretofore, hydrophilic ceramics or synthetic resin has been used for this kind of member, and the member is used in a state where the member is exposed as it is.

[0003]

For example, a member such as an insulator for electric insulation has a drawback that, in weather conditions such as rainfall and fog, water droplets adhere to the outer surface of the member, resulting in poor electric insulation.
In addition, in the case of aluminum sashes and the like, which are house building materials, a large amount of water droplets are generated due to dew condensation in winter, and molds are generated due to the water droplets.

An object of the present invention is to provide a water-repellent member capable of easily preventing the attachment of water droplets, and to provide a method suitable for manufacturing the member.

[0005]

According to the present invention, a monomer is subjected to plasma polymerization using a glow discharge generated by applying a high DC voltage in a vacuum, and a water-repellent plasma polymerization obtained on the positive electrode side. The above object is achieved by a member having a film on the surface. The plasma polymerized film is preferably a plasma polymerized film using a vinylidene fluoride monomer as a raw material.

Another object of the present invention is to provide a method in which a monomer gas of vinylidene fluoride is present as a raw material gas in a vacuum processing chamber under a vacuum, and a positive direct current This is achieved by applying a high voltage to generate glow discharge to cause plasma polymerization, and forming a water-repellent plasma polymerized film on the surface of the member to be processed. The member to be processed is desirably made of, for example, metal, glass, ceramics, synthetic resin, or the like.

A member to be processed made of metal, glass, ceramics or synthetic resin is prepared in a vacuum processing chamber under a vacuum, and a positive DC voltage is applied directly to the member to be processed itself or to an electrode holding the member to be processed. The above object can also be achieved by applying a voltage to generate glow discharge to cause plasma polymerization, and forming a water-repellent plasma polymerized film on the surface of the member to be processed.

As the member to be processed, for example, a house building material such as a sash or an insulator is desirable.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As a member to be treated for obtaining a water-repellent member of the present invention, a member to be treated generally used, made of glass, ceramics, synthetic resin or metal, is used as described above. Can be According to an example of the embodiment of the present invention, the water-repellent member is formed by directly forming a water-repellent plasma-polymerized film 2 on at least one surface of a member to be processed 1 as shown in FIG. As the plasma polymerized film 2, vinylidene fluoride gas is formed by decomposing and exciting vinylidene fluoride monomer gas in a plasma generated by applying a high DC voltage and polymerizing on the surface of the member 1 to be processed. The polymer film is suitable because it has sufficient water repellency. The plasma polymerized film 2 is usually formed to a thickness of 100 to 300 nm.

According to experiments conducted by the present inventors, the plasma polymerized film has a property of increasing the contact angle of a water droplet contacting the film, and the contact angle is substantially equal to the applied voltage at the time of forming the plasma polymerized film. It is known that they are arranged, but in this case, it is necessary to form a conductive film on the member to be processed before film formation,
This conductive film forming process complicates the film forming process and causes an increase in cost. Thus, by conducting further experiments and searching for a film forming method and a kind of film that can be manufactured easily and inexpensively, the contact angle is also substantially proportional to the pressure of the monomer gas at the time of forming the plasma polymerized film. By controlling the pressure of the monomer gas and the applied voltage during the formation of the plasma polymerized film, the contact angle with water is high, and particularly when the film is formed on the positive electrode side, high water-repellent plasma polymerization exceeding 160 ° is obtained. It has been found that a membrane can be produced. Further, when a plasma polymerized film is obtained by using a vinylidene fluoride monomer gas, the monomer is convenient as a raw material of the plasma polymerized film because the contact angle of the polymerized film changes in proportion to the gas pressure.

FIG. 2 shows an example of an apparatus which can be used for carrying out the production method of the present invention. The apparatus comprises a vacuum exhaust port 3 connected to a vacuum pump and an evaporation source containing the raw material monomer 4 of the plasma polymerization film 2. A vacuum processing chamber 5 having an inlet 10 is provided, and a glass plate, a ceramics plate, a synthetic resin plate, or a metal plate to be processed 1 is placed on a holding member (not shown), and The processing target 1 is provided with a mesh electrode 6 connected to a DC power supply 8 immediately above a film forming surface of the processing target member 1, that is, a surface facing the counter electrode 7.

When the above apparatus is used, first, the inside of the vacuum processing chamber 5 is evacuated to 10 ⁻² Pa, for example, and the vapor of the raw material monomer 4 is evaporated from the evaporation source while adjusting the monomer gas introduction valve 9. It is introduced into the chamber 5 and has a predetermined pressure,
For example, the pressure is set to 30 Pa. Next, when a positive DC high voltage is applied from the DC power supply 8 to the mesh electrode 5, a glow discharge occurs, whereby the vapor is decomposed and excited, and the plasma polymerized film 2 is formed on the processing target member 1. .

The applied voltage during the formation of the plasma polymerized film 2 and the contact angle of the film 2 with water have a linear relationship. For example, when the pressure is 30 Pa using a vinylidene fluoride monomer, FIG. As described above, the contact angle of the water droplet changes in proportion to the applied voltage, and a good water-repellent film having a contact angle of 160 ° at a voltage of +1 kV can be obtained.

When the applied voltage is 1 kV or more, the discharge becomes unstable and uniform film formation cannot be performed. When the gas pressure is higher than 30 Pa, the contact angle with water becomes smaller, and the pressure becomes lower than 30 Pa. And the discharge becomes unstable.

The size and shape of the member to be processed 1 are arbitrary.
For example, even in the case of a member to be processed having a curved surface or a member having a large surface area such as 1 × 1 m, the plasma polymerized film 2 can be uniformly formed by providing the mesh electrode 5 along the surface of the member to be processed 1. Can be formed. The distance between the surface of the member to be processed 1 and the mesh electrode 6 is preferably about 10 mm.

Another example of an apparatus that can be used to carry out the manufacturing method of the present invention is that the apparatus shown in FIG. 2 does not have a mesh electrode and directly or directly holds the member to be processed. Is configured so that a positive direct current high voltage can be applied to an electrode which also serves as a holding member for use. That is, in this apparatus, a member made of metal, glass, ceramics, or synthetic resin is used as a member to be processed. However, a positive DC high voltage is directly applied to the member itself to be processed, or the member to be processed is made of metal. It is configured so that a glow discharge can be generated by applying a positive direct current high voltage to the member holding electrode.
Using such an apparatus, a water-repellent plasma polymerized film can be formed in the same manner as in the apparatus shown in FIG.

[0017]

(Embodiment 1) Using the apparatus having the structure shown in FIG. 2, a 5 mm thick, 0.3 × 0.times.
A 3 m plate glass window substrate 1 is installed, the inside of the vacuum processing chamber 5 is evacuated to 10 ⁻² Pa, and then, from the evaporation source containing the vinylidene fluoride monomer, into the chamber 5 through the inlet 10. The monomer vapor was introduced, the pressure was adjusted to 30 Pa, and a high voltage of +1 kV was applied to the mesh electrode 6. The mesh electrode 6
Glow discharge is generated between the window substrate 1 and the counter electrode 7.
When the plasma polymerized film 2 of vinylidene fluoride was formed with a thickness of 100 nm on the surface of, the application of the voltage was stopped, the glow discharge was extinguished, and the film formation was stopped there. When the obtained window material was inclined and water droplets were applied to the surface thereof, the water droplets flowed down and no water film was formed. The contact angle of the vinylidene fluoride plasma polymerized film was 160 °.

In the above embodiment, a window glass substrate is used as a member to be processed. However, the same applies to a plasma polymerized film obtained using a member to be processed made of a metal plate, a ceramic plate and a synthetic resin plate. A water-repellent plasma polymerized film having a high contact angle was obtained.

Thus, it is possible to improve the water repellency of the building material for a house and the insulator.

(Embodiment 2) Using the apparatus shown in FIG. 2 in which a mesh electrode is not provided in a vacuum chamber, a metal having a thickness of 2 mm and a length and width of 0.4 × 0.4 m is placed in the vacuum chamber. A member to be processed was placed, and a high voltage of +1 kV was directly applied to the member to be processed to form a film in the same manner as in Example 1. As in Example 1, a repellent having a high contact angle was obtained. An aqueous plasma polymerized film could be formed.

In place of the above metal plate, a thickness of 5 m
m, a synthetic resin plate or a ceramic plate of 0.3 × 0.3 m in length and width was placed on the electrode for holding the member to be processed, and a positive DC high voltage was applied to this electrode. As a result, as in the case of Example 2, a water-repellent plasma-polymerized film having a high contact angle could be formed.

[0022]

According to the present invention, a water-repellent film made of a vinylidene fluoride polymer obtained on the positive electrode side by plasma polymerization utilizing a glow discharge generated by applying a positive direct current high voltage is provided. Since it is formed directly on the surface of the member to be processed, it is possible to provide a highly water-repellent member that is simple to manufacture and low in manufacturing cost and that can easily prevent the attachment of water droplets.

Further, according to the manufacturing method of the present invention, a glow discharge is performed by applying a high positive DC voltage to a mesh electrode provided directly above the surface of a member to be processed in a vacuum processing chamber in the presence of a monomer gas in a vacuum. To generate a glow discharge by applying a positive DC high voltage directly to the member to be processed itself or to an electrode holding the member to be processed, thereby causing a plasma polymerization to be performed. Since the water-repellent plasma polymerized film is formed directly on the surface, the pressure and applied voltage of the monomer gas at the time of forming the plasma polymerized film are controlled to form a high contact angle with water, especially at the positive electrode side. When the film is formed, a highly water-repellent member having a contact angle exceeding 160 ° and having a plasma polymerized film capable of easily preventing the attachment of water droplets can be easily and inexpensively manufactured.

[Brief description of the drawings]

FIG. 1 is a cut side view of an example of a water-repellent member of the present invention.

FIG. 2 is a schematic cross-sectional view of an example of an apparatus used in the manufacturing method of the present invention.

FIG. 3 is a diagram showing a relationship between an applied voltage and a contact angle of a plasma-polymerized film with water.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Processed member (window base material) 2 Plasma polymerization film 3 Vacuum exhaust port 4 Monomer 5 Vacuum processing chamber 6 Reticulated electrode 7 Counter electrode 8 DC power supply 9 Monomer gas introduction valve 10 Inlet

Claims (5)

[Claims] In a vacuum processing chamber, a monomer gas of vinylidene fluoride is present as a raw material gas under a vacuum, and a positive DC high voltage is applied to a mesh electrode provided immediately above the surface of a member to be processed prepared in the vacuum processing chamber. A method for producing a water-repellent member, characterized in that a plasma-polymerized film is formed on the surface of the member to be treated by applying the voltage to generate a glow discharge for plasma polymerization, thereby obtaining a water-repellent member. 2. A method in which a monomer gas of vinylidene fluoride is present as a raw material gas in a vacuum processing chamber under a vacuum, and a positive electrode is directly applied to a processing target member prepared in the vacuum processing chamber or to an electrode holding the processing target member. Applying a DC high voltage to generate glow discharge for plasma polymerization, and forming a water-repellent member by forming a water-repellent plasma-polymerized film on the surface of the member to be processed. Production method. 3. The method for producing a water-repellent member according to claim 1, wherein the member to be processed is made of metal, glass, ceramics or synthetic resin. 4. A water-repellent film comprising a vinylidene fluoride polymer obtained by plasma polymerization by a glow discharge generated by applying a high DC voltage in the presence of a vinylidene fluoride monomer in a vacuum and obtained on the positive electrode side A water-repellent member, characterized by having on its surface. 5. The water-repellent member according to claim 4, wherein the water-repellent member is a water-repellent sash or insulator.