JPH06271336A - Water-repellent article and its production - Google Patents

Abstract

PURPOSE:To provide a transparent or opaque article of glass etc., having water repellency and excellent in durability such as resistances to weather water, moisture and wear. CONSTITUTION:The objective water-repellent article consists of a substrate, a silicon dioxide-contg. coating film formed on the surface of the substrate by plasma CVD and a water-repellent layer of an org. silazane compd. formed on the surface of the coating film.

Description

Detailed Description of the Invention

[0001]

This invention relates to water repellent articles, especially construction,
Windshields for cars, vehicles, aircraft or ships,
TECHNICAL FIELD The present invention relates to a water-repellent article in which a transparent or opaque article such as an optical component lens or other glass products is coated with a water-repellent coating having excellent durability such as weather resistance, moisture resistance, water resistance and abrasion resistance, and a method for producing the same.

[0002]

2. Description of the Related Art When a surface of a glass article is treated to be water repellent, 1) water drops containing a contaminant component do not remain on the surface of the glass, so that the glass can be prevented from being contaminated or burnt.
2) When water-repellent glass is used for windshields and side windows of automobiles, even when driving in the rain, rainwater adhering to the glass surface is blown away by wind pressure, ensuring the driver's view and improving driving safety. The effect of can be expected. Further, as a method for producing such a water-repellent glass, a water-repellent agent composed of an organosilicon compound centering on polydimethylsiloxane or a fluorine-containing silicon compound is wet-coated on the glass surface, and a dry method by plasma or vapor deposition is used. A coating method or the like is generally used.

[0003]

However, in the method of directly applying the water repellent agent to the glass, it is difficult to maintain the water repellent performance for a long period of time because the adhesive force between the water repellent agent and the glass is weak. .

The present invention eliminates such drawbacks and is excellent in durability such as weather resistance, water resistance, moisture resistance and abrasion resistance,
Moreover, it is an object to provide a transparent article such as glass or an opaque article having water repellency.

[0005]

Means for Solving the Problems The inventors of the present invention can improve the adhesion performance between a substrate and a water repellent by forming a silicon dioxide-containing coating by a special production method and improve the above durability performance. I found it.

That is, the present invention relates to a substrate and a plasma CV.
A water repellent article comprising a silicon dioxide-containing coating formed on the surface of a substrate by the method D, and a water repellent layer formed on the surface of the coating, the organic silazane compound.

The present invention will be described in detail below. In the present invention, a transparent substrate and an opaque substrate can be used as the substrate. Examples of the transparent substrate include ordinary inorganic glasses such as soda-lime silicate glass, borosilicate glass, and quartz glass. Examples of the opaque substrate include various metals and opaque glass.

In the present invention, a silicon dioxide-containing coating is formed on the surface of the base material by the plasma CVD method. This silicon dioxide film is formed as follows, for example. That is, a high-density arc discharge plasma is generated in a vacuum chamber by a plasma generator having a plasma source and an anode, which is installed in a vacuum chamber in which a decompressed atmosphere can be adjusted, and the generated plasma is magnetic field means. The sheet plasma is transformed into a sheet plasma by introducing a gas containing a raw material gas from a gas introduction tube arranged on one side of the sheet plasma, and a substrate is provided on the opposite side of the gas introduction tube with the sheet plasma interposed therebetween. And, while the surface of the substrate is opposed to the sheet surface of the sheet plasma and is moved in the direction connecting the plasma generation source and the anode, the source gas component passed through the sheet plasma is transferred to the substrate surface. To precipitate. The plurality of plasmas generated from the plurality of plasma generators are deformed into a sheet shape by magnetic field means, and the plurality of sheet deformed plasmas are formed adjacent to each other in the same plane. It is preferable to use a sheet plasma having a larger area in order to uniformly coat a film on a large-area substrate.

The gas for generating the sheet plasma is not particularly limited, but from the viewpoint of discharge stability, A
It is desirable to use a single gas such as r, He, H2 or a mixed gas thereof.

The gas for forming the silicon dioxide film is not particularly limited, and a liquid raw material may be supplied into plasma together with a carrier gas such as hydrogen. For example, monosilane (S
A silane gas such as iH4) or disilane (Si2H6) or a silane derivative gas such as SiF4, SiCl4 or Si (CH3) 4 can be used. As the reaction gas, oxygen, nitrous oxide or the like can be used. For the details, the method described in JP-A-4-110473 can be used.

If the thickness of the silicon dioxide-containing coating coated on the surface of the base material is too small, the improvement in adhesiveness described later cannot be expected. On the other hand, if the thickness is too large, it is not economical, so the thickness is usually 10 to 500 nm, preferably 20 to 150 nm. In the present invention, a water repellent layer made of an organic silazane compound is further formed on the silicon dioxide-containing coating film coated on the substrate. An organosilazane compound is a nitrogen analog of polysiloxane,
Includes everything that has a -Si bond. For example, as a typical example, hexamethyldisilazane, CF3 (CF
2) 7CH2CH2Si (NH) 3/2, NH [Si (CH3)
2CH2Cl] 2,1,3-divinyl-1,1,3,3-
Tetramethyldisilazane, 1,3-diphenyltetramethyldisilazane, octamethylcyclotetrasilazane,
1,1,3,3-tetramethyldisilazane, polytitanosilazane, polydisilacyclobutasilazane, polyalkoxysilylalkylenedisilazane, hexamethylcyclotrisilazane, organotetrachlorosilazane, hydridothiosilazane, and the like, The present invention is not limited to these descriptions. In addition, these silazane compounds may be used as a mixture, and an acid,
You may use it, after making a partial hydrolysis-condensation product with alkali etc. Further, these silazane compounds may be copolymerized with those having an acryl group, an epoxy group or other modifying groups. Further, these silazanes may be partially reacted with organochlorosilane, bis (methyldichlorosilyl) ethane or the like. Further, in order to lower the surface energy of these silazane compounds and increase the water repellency, organic fluorine-containing silazane compounds in which these compounds are partially substituted with fluorine or the like may be used. Further, a small amount of SiO bond may be contained in these silazane compounds. Also,
A part of these silazane compounds may be treated with ammonia.

The silazane compound is water (H 2 O) adsorbed in air or on the surface of the substrate or silanol group (S) on the surface.
i-OH), but the silicon dioxide-containing coating used in the present invention has a large number of silanol groups on the surface, so the bond density between the silicon dioxide-containing coating and the water repellent layer made of an organic silazane compound is high. It is considered to be.

In the present invention, if desired, a solvent, a curing agent, a curing catalyst, etc. may be added to the silazane compound.

The solvent must be one that dissolves the above organic silazane compound and can be evenly applied to the substrate. Generally, fluorine-based, aliphatic-based or aromatic-based,
Examples thereof include ketone type and ester type solvents.

With respect to the organic silazane compound having a hydroxyl group in the molecular chain, a curing agent such as polyisocyanate can be added to improve the moisture resistance and water resistance of the film. It is not always necessary to use a curing agent, but it may be appropriately selected depending on the application.

Further, the curing catalyst is not necessarily required, but is suitably used for promoting the curing of the organic silazane compound having a functional group and increasing the stability of the film. When the organosilazane compound has an alkoxy group as a functional group, the catalyst for promoting hydrolysis and condensation of the alkoxy group is an acid catalyst such as hydrochloric acid, sulfuric acid, nitric acid, glacial acetic acid, sodium hydroxide, potassium hydroxide, ammonia, etc. Alkaline catalysts, ammonium perchlorate, magnesium perchlorate, aluminum acetylacetonate, etc. are mainly used. When the organic silazane compound has an isocyanate and a hydroxyl group as functional groups, a tin catalyst such as dibutyltin dilaurate and an amine catalyst are generally used as a reaction catalyst for the isocyanate and the hydroxyl group. Further, a platinum catalyst is generally used to bond the mercapto group and the vinyl group. A large number of catalysts such as azo-based or peroxide-based catalysts are commercially available for thermal polymerization of (meth) acryloxy groups, and acetophenone-based and benzophenone-based catalysts for polymerization by ultraviolet rays or electron beams. Known methods such as anion and cation catalysts are used for the polymerization of vinyl groups.

As the method for forming the water repellent layer made of the organic silazane compound, a method of coating a solution containing the organic silazane compound on a substrate having a silicon dioxide film formed thereon, vapor deposition of the organic silazane compound, plasma Various methods such as a dry coating method by polymerization or a method of evaporating and adsorbing the organic silazane compound can be used. However, in consideration of cost, a method of applying a solution containing the above organic silazane compound is preferable.

As a method for applying the solution containing the above organic silazane compound, a dipping method, a spray method, or a commonly used method is used.
The roller coating method, the flow coating method, the rubbing method, etc. are used. The substrate coated with the organic silazane compound in this manner is air-dried, or at a temperature of 50 to 200 ° C. for 1 to 12
A water-repellent film can be formed on the silicon dioxide film by heat treatment for 0 minutes. The application method, drying and heat treatment times, etc. may be appropriately selected according to the required product. The coating thickness is several nm (1 molecular layer) to 50.
0 nm is desirable, and more preferably 10 to 100 nm. If the coating film thickness exceeds 500 nm, the water-repellent layer will have poor abrasion resistance and the appearance after the abrasion test will be poor.

[0019]

The silicon dioxide film formed according to the present invention exhibits good properties as an adhesive layer of an organic silazane compound and / or an organic fluorine-containing silazane compound and is excellent in durability such as water resistance and moisture resistance. A water-repellent glass was obtained.

[0020]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

<Evaluation and test method> 1) Contact angle: Contact angle meter (CA- manufactured by Kyowa Interface Science Co., Ltd.)
Using D), the contact angle of water was measured by the sessile drop method. Five points were measured for each sample, and the average value was used as the contact angle value. 2) Hot water resistance: The contact angle was measured after the sample was immersed in boiling water for 6 hours.

EXAMPLES The present invention will be described below based on examples. FIG. 1 shows an apparatus for forming a silicon dioxide film according to the present invention. Two sets of plasma generators each having a plasma generator 4 and an anode 5 are provided in a vacuum chamber 1 in which a reduced pressure atmosphere can be adjusted. Two sets of ring-shaped air-core coils 6 were installed so that the magnetic field formed by them was directed from the plasma generation source 4 to the anode 5. Then, two high-density plasma streams generated by the arc discharge generated from the plasma generation source 4 were drawn into the film forming chamber 13. The soda lime glass substrate 3 manufactured by the float method is placed facing the plasma flow,
The substrate 3 is moved substantially parallel to the plasma flow. Further, in order to make the drawn plasma into a sheet shape, the pair of permanent magnets 7 are connected to the plasma source 4 and the film forming chamber 13.
By sandwiching the N pole surface so as to face each other from the vertical direction in FIG. 1 and arranging the N pole or S phase of the permanent magnet 7 in parallel with the glass substrate 3 forming the film. , The plasma is crushed in a direction parallel to the glass substrate 3 to form the sheet plasma 11. At this time, as shown in FIG. 2, the spread state of the plasma is such that the two sheet plasmas 11a and 11b are overlapped at the end and are continuously connected.
It becomes one sheet plasma.

On the other hand, the supply nozzle 9 for supplying the raw material gas and the reaction gas for forming the thin film is provided with the sheet plasma 1
The glass substrate 3 is placed at a position opposite to the substrate with respect to 1.
A gas supply nozzle having a large number of nozzles each having a plurality of minute diameters is used in a direction perpendicular to the moving direction of.

The inside 2 of the vacuum tank 1 is evacuated from an exhaust port (not shown) by a vacuum pump (not shown). A plasma generation source 4 having an intermediate electrode 12 built in is formed on the wall (wall perpendicular to the paper surface) of the vacuum chamber on the one upstream side in the transport direction (indicated by an arrow) of the glass substrate 3 in the film forming chamber 13, Air core coil 6, permanent magnet 1 for making plasma into a sheet
An anode 5 and an air-core coil 6 are attached to the wall surface (wall perpendicular to the paper surface) 2 of the vacuum chamber on the downstream side. The anode 5 is connected to a large current type DC power source 8, and a negative voltage is applied from the DC power source 8 to the plasma generation source 4. Further, the plasma generation source 4 is provided with a discharge gas introduction pipe 10 to introduce a discharge gas such as Ar or He. The substrate glass 3 is adapted to be covered with the SiO2 film when it is transported rightward or leftward over the plasma. The gas supply nozzle 9 is provided below the sheet plasma in the film forming chamber 13.

The inside of the vacuum chamber 1 is set to 1.
After evacuating to a pressure of 3 × 10 ⁻⁴ Pa, Ar is introduced as a discharge gas by about 30 sccm from the discharge gas introduction pipe 10 and a current of 100 A is supplied to each plasma generator to generate about 70 cm from the plasma generation source 4. Two sheet plasmas were generated adjacent to each other with the remote anode 5. At this time, the plasma 11 has a thin shape spread in the plane parallel to the plane of the substrate by the air-core coil 6 and the permanent magnet 7. When the apparatus of FIG. 1 is viewed from above, it is as shown in FIG. Each of the sheet plasmas formed from the two plasma generation sources is a sheet plasma that spreads over a large area by adjoining in the peripheral portion.

From the gas supply nozzle 9, 170 sccm of SiH4 gas and 2100 sccm of O2, the flow rate of which was controlled by a flow meter provided outside each separate apparatus.
Gas was supplied into the plasma 11. The pressure in the vacuum chamber 2 at this time was 1.1 Pa as indicated by a vacuum gauge.

In this state, a soda lime glass substrate having a thickness of 30 mm and a thickness of 3 mm and manufactured by the float method is moved from the left to the right at a conveying speed of 600 mm / min to form a SiO2 film on the glass substrate. Was formed. After stopping the supply of gas and the supply of electric power, the inside of the vacuum chamber 2 is returned to atmospheric pressure, and the coated glass substrate is removed from the vacuum chamber 2.
I took it out of. The thickness of the formed silicon dioxide film is 10
It was 0 nm.

The glass substrate having a silicon dioxide film produced as described above was treated with a disilazane water repellent KP801 [CF ₃
(CF ₂ ) ₇ CH ₂ CH ₂ Si (NH) _3/2 , manufactured by Shin-Etsu Chemical Co., Ltd.] and pulled up at a speed of about 350 mm / min to apply a water repellent. After air-drying for 10 minutes, 1
A water repellent layer was prepared by baking at 50 ° C. for 30 minutes. The thickness of the obtained water repellent layer was about 10 nm. The measurement results of the contact angle of this sample are shown in the table.

Comparative Example A water-repellent glass was prepared in the same manner as in Example 1 except that the substrate on which the silicon dioxide film was formed was changed to a substrate on which this film was not formed.

The durability of the water-repellent glass produced as described above was evaluated and shown in the table.

It is apparent that the water-repellent glass has higher durability in Examples than in Comparative Examples.

[Table 1] Table ------------------ Contact angle (°) ------------------ −−−−−−−−−− Initial hot water resistance −−−−−−−−−−−−−−−−−−−−−−−−− Example 107 101 Comparative example 100 67 ----- −−−−−−−−−−−−−−−−−−−−−−

[Brief description of drawings]

FIG. 1 is a plan view of an apparatus used to carry out the present invention.

2 is a cross-sectional view of the device shown in FIG.

[Explanation of symbols] 1 ... Vacuum layer, 2 ... Vacuum layer inside, 3 ... Glass substrate, 4
..Plasma generation sources, 5 ... Anodes, 6 ... Air core coils,
7 ... Permanent magnet, 8 ... Large current type DC power supply, 9 ... Gas supply nozzle, 10 ... Discharge gas introduction pipe, 11 ... Sheet plasma

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshio Kado 3-5-11 Doshomachi, Chuo-ku, Osaka City Japan Sheet Glass Co., Ltd.

Claims (2)

[Claims] 1. A water-repellent article comprising a substrate, a silicon dioxide-containing coating formed on the surface of the substrate by a plasma CVD method, and a water-repellent layer made of an organic silazane compound formed on the surface of the coating. 2. A plasma generated by using a plasma generator having a plasma source and an anode installed in a depressurized vacuum chamber is transformed into a sheet plasma by a magnetic field means, and a raw material is contained in the sheet plasma. A gas containing gas is introduced to form a silicon dioxide film on the surface of a base material placed in a vacuum chamber, the base material is taken out of the vacuum chamber, and then a solution containing an organic silazane compound on the surface of the silicon dioxide film. A method for producing a water-repellent article, which comprises applying and drying or curing.