JPH0570177A - Antistatic glass and its production - Google Patents

Abstract

PURPOSE:To improve through-vision properties and resistant light, weather and chemicals, etc., by forming a film which is an outermost surface layer thin film having a prescribed film thickness and surface resistivity on the surface of a glass plate by a reactive DC sputtering method. CONSTITUTION:A target of metallic Sn is set and a glass plate is introduced and arranged in a vacuum thin film laminator in which a mixed gas of O2 and Ar is used as an atmosphere at 0-75wt.% ratio of O2/(O2+Ar). The glass plate is then subjected to reactive DC sputtering to coat the glass plate surface with a laminated thin film. Heat treatment is subsequently carried out at 100-500 deg.C in air atmosphere so as to provide a tin oxide thin film of high resistance having 200-2000 A film thickness of the outermost surface layer thin film and 10<6> to 10<9>OMEGA/square surface resistivity. The objective antistatic glass in which the tin oxide thin film has oxygen deficiency and 260% visible light transmittance and the color tone of transmitted light is colorless or a light chromatic color is then produced.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention can prevent the electrification of an insulator and is useful for a clean room or a display showcase. Further, the present invention can be applied to a wide variety of fields such as a glass for a copying machine. The present invention provides an antistatic glass and an efficient manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, semiconductor-related industries, precision parts-related industries, etc. have developed more and more and become socially important. Above all, the cleanliness in a clean room that is extremely reluctant to remove dust is the product. This will greatly affect the deterioration of quality or yield. That is, an insulating material such as dust floats in the air and hits a wall or the like. At that time, if the wall material is an insulating material, friction occurs between the dust or the air flow and the wall material to generate static electricity and electrostatic adsorption. It causes the dust to adhere to the wall and reduces the cleanliness, which is the main cause of product defects.

Therefore, an antistatic technique for removing the static electricity charged so that the attached dust is separated from the wall material at an appropriate time is becoming very important. Among them, as an antistatic method, for example, a method in which Sn is doped with In by a reactive sputtering method and the resistance value is about 10 ⁴ to 10 ⁶ is used, and a method of using a doping material is used. A method to prevent dust from adhering by using a wall material with a resistance value slightly higher than the surface resistance value, for example, kneading a conductive material into a polymer material such as acrylic, or using a surfactant / hydrophilic resin Coating (10 ³ to 10 ⁴ Ω / □ when using a charged paint) [JP-A-63-67
No. 92, etc.], or by spraying a conductive metal material,
There is a method such as applying a conductive metal filler.

The surface resistivity of the wall material is, for example, 10 ³ Ω.
/ □ or less to remove the static electricity by grounding to reduce the static electricity, such as low resistance Au, ITO (indium tin oxide), SnO ₂ , TiO ₂ / Ag / TiO ₂ conductive thin film or each layer film Etc. are used. Further, the surface of the inorganic substrate has a large number of fine ridges having a height of 0.1 to 2.0 μm, and the surface has a specific resistance of 10 ⁶ Ω · cm to 1
It is known from JP-A-62-176946 that a transparent inorganic coating film of a tin compound or an indium compound is provided by a sol-gel method of 0 ⁴ MΩ · cm.

[0005]

Among the conventional methods as described above, for example, the method of kneading a conductive material cannot be kneaded into a large-sized glass substrate or the like and cannot be adopted. Even if it is contained, it is likely to be deteriorated by ultraviolet rays, and the method using a surfactant may be inferior in adhesiveness even to a wall material, and it is difficult to use because a similar phenomenon is expressed even in a glass substrate. It is difficult to obtain transparency with the method of spraying a conductive metal material or application of a conductive metal filler, and peeling of the metal material is likely to occur, so it is necessary to install a ground in the method using a low resistance film The sol-gel method has a specific resistance of 10 ⁶ Ω · cm to 10 ⁴ MΩ · cm.
In the case of forming a transparent inorganic film of a tin compound or an indium compound, which has to be applied to a large-sized glass substrate by a spray method, a dipping method, or a flow-down method, it is necessarily abrasion resistant or durable. It cannot be said.

In any case, in recent years, the glass substrate has been increasingly used as a wall material, and it has abrasion resistance, durability, and light resistance, and it is not necessary to install a ground. And has an antistatic property, especially 10
It was hard to say that the surface resistivity of ⁶ to 10 ⁹ Ω / □ could be adjusted sufficiently.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks of the prior art, and was specified by making oxygen defects existing in a tin oxide film without using a doping agent. Provided are an antistatic glass and a method for producing the same, which can have a surface resistivity of ⁶ to 10 ⁹ Ω / □ arbitrarily and easily and can be used as an antistatic film and has sufficient transparency and durability. It is a thing.

That is, according to the present invention, in the laminated thin film coated on the surface of the glass plate, the outermost surface thin film is a thin film formed by the reactive DC sputtering method, and the thin film has a thickness of 200 to 20.
An antistatic glass, which is a tin oxide thin film having a film thickness of 00Å, and which is a high resistance thin film having a surface resistivity of 10 ⁶ to 10 ⁹ Ω / □. Also, the tin oxide thin film has oxygen defects and has a visible light transmittance of 6
The above-mentioned antistatic glass, which is 0% or more and has a colorless or pale color tone of transmitted light.

Further, according to the present invention, in a vacuum thin film laminating apparatus, a target of metallic tin is set, and an atmosphere in which a mixed gas of oxygen and argon is O ₂ / (O ₂ + Ar) = 0 to 75%, As the outermost surface thin film of the laminated thin film-coated glass plate, the film thickness was 20 by reactive DC sputtering.
A process for producing antistatic glass, characterized in that a tin oxide thin film having a thickness of 0 to 2000 Å is formed so as to be a high resistance thin film having a surface resistivity of 10 ⁶ to 10 ⁹ Ω / □.

Further, according to the present invention, in a vacuum thin film laminating apparatus, a metallic tin target is set, and an atmosphere in which a mixed gas of oxygen and argon is O ₂ / (O ₂ + Ar) = 0 to 75%, As the outermost surface thin film of the laminated thin film coated glass plate, the film thickness is 2 by the reactive DC sputtering method.
A tin oxide thin film having a thickness of 0 to 2000 Å is formed, and a surface resistivity of the tin oxide thin film is a high resistance thin film of 10 ⁶ to 10 ⁹ Ω / □ in an air atmosphere of 100 to 500 °.
A method for producing an antistatic glass, characterized in that a heat treatment is performed at a treatment temperature of C. And the mixed gas is O ₂
When the film is formed in an atmosphere of / (O ₂ + Ar) = 0 to 30%, after the film is formed, it is 100 to 250 ° in air.
The method for producing antistatic glass as described above, characterized in that heat treatment is performed at a treatment temperature of C. In addition, the mixed gas is O
When the film is formed in an atmosphere of ₂ / (O ₂ + Ar) = 20 to 75%, after the film formation, 200 to 50 in air.
The respective methods for producing antistatic glass described above are characterized in that heat treatment is performed at a treatment temperature of 0 ° C.

Here, the outermost surface thin film is a thin film formed by the reactive DC sputtering method, and the thin film has a thickness of 200 to 200.
The tin oxide thin film having a film thickness of 0 Å means that the tin oxide thin film has the highest chemical durability among the oxides whose surface resistivity can be 10Ω / □ or less, and the reduction of hydrogen in the nascent stage Although it dissolves only by, it does not dissolve in acid or alkaline solution and is suitable as the outermost surface thin film,
In addition, the color tone of transmitted light is colorless or pale, and the visible light transmittance is 60% or more, which is preferable, and the tin oxide thin film is formed by the reactive DC sputtering method, for example, a metal tin target. Is inexpensive, it is easy to control the surface resistance of the thin film, and the deposition rate is high even in reactive sputtering deposition in the presence of oxygen gas. This is because a surface thin film can be obtained.

Further, if the film thickness is less than 200Å,
For example, if the surface resistivity is about 100 Å, it may not always be possible to sufficiently guarantee the quality of the outermost surface thin film under various conditions or periods even if the intended purpose can be achieved. Because it ’s hard to say, 2
If it exceeds 000Å, the coating time becomes too long, which is not economically preferable.
It is about 1500Å.

Further, the surface resistivity of the tin oxide thin film is 10
The high resistance thin film of ⁶ to 10 ⁹ Ω / □ means that when the insulating material particles such as dust floating in the air hit the wall surface and the wall material is an insulator, Static electricity is generated by friction with the air flow containing air, and dust adheres to the wall surface due to electrostatic attraction, but if the wall surface is made of a material whose half-life of the charged charge is 2 seconds or less. , I found that the dust did not adhere to the wall surface,
The surface resistivity of the tin oxide thin film having a half-life of 2 seconds or less was confirmed by a static Honest meter (manufactured by Shishido Electrostatics) to be about 10 ⁹ Ω / □ or less, and the upper limit of the surface resistivity was 10 ⁹ Ω. / □ or less. On the other hand, for some reason, charged human beings have a resistance of 10 ⁶ Ω / □
When a human touches a lower object such as a metal doorknob, an electric discharge is generated and a human being is shocked. The lower limit of the surface resistivity is 10 ⁶ Ω / □. That is, it is possible to sufficiently exert the static electricity diffusive action and to exhibit the antistatic effect, so that it is possible to eliminate the need to install a ground, for example.

Further, it is preferable that the visible light transmittance is 60% or more and the color tone of transmitted light is colorless or light colored. For example, sufficient transparency is required for automobile window glass. Even in such a case, safety can be ensured by using, and it is more preferably about 70% or more.

Furthermore, the reason why the metallic tin target is set by the reactive direct current sputtering method and the laminated coating is performed in the atmosphere of the mixed gas of oxygen and argon is to adjust the oxygen gas in the film forming atmosphere. , Especially O
_By adjusting oxygen defects (anion vacancies) in the tin oxide thin film, which are manifested by film formation in a controlled atmosphere in which ₂ / (O ₂ + Ar) = 0 to 75% or heat treatment in air after film formation This is because, depending on the behavior to be exhibited, the desired antistatic property, transparency, or the like is achieved, and the above-described high workability and high economic efficiency are provided.

Above all, after film formation, 1
The heat treatment is performed at a temperature of 00 to 500 ° C. when the temperature is lower than 100 ° C. or higher than 500 ° C., after adjusting the oxygen gas in the film forming atmosphere of the mixed gas of oxygen and argon, the film is formed. This is because adjustment to 10 ⁶ to 10 ⁹ Ω / □ cannot be performed sufficiently.

The glass plate is not only a so-called inorganic transparent plate glass, but also an organic resin plate or a glass-like material such as a film.
It is needless to say that the shape is not particularly limited, and it can be used as a tempered glass, a single plate as a flat plate or a bent plate glass, and can also be used as a multi-layer glass or a laminated glass.

[0018]

As described above, the antistatic glass and the method for producing the same of the present invention are the glass plate which is an insulator in the reactive direct current sputtering method in the mixed gas atmosphere of O ₂ and Ar with the target of metallic tin. tin oxide thin film can be coated on the surface, or by further performing a particular heat treatment and can be adjusted as appropriate oxygen defects Some of the coating film is expressed, for example, as shown in FIG. 1, O ₂ / ( O
₂ + Ar) in the atmosphere of 0 to 60% by the sputtering method, the surface resistivity of the coating thin film is obtained, and the surface resistivity can be adjusted by adjusting the O ₂ gas content. A specific high resistance thin film of 10 ⁶ to 10 ⁹ Ω / □ can be arbitrarily selected, and if the O ₂ gas content is 75% or less, the coated thin film after film formation is 100 to 500 in air.
By heat-treating at a specific temperature of ° C, it becomes possible to more reliably and arbitrarily select a value between 10 ^{6 and} 10 ⁹ Ω / □, and the transparency is high and the abrasion resistance is more excellent. As a result, it becomes more durable and can be used as a veneer enough to use it as a wall material such as windows in clean rooms where dust is extremely disliked. Even if it adheres to the wall, it will separate from the wall material, and it will exhibit a sufficient antistatic effect, and will not cause electrostatic damage to the human body. Furthermore, it will be used for display cases and automobiles. It can be used as window glass for
It is intended to provide an excellent antistatic glass and a method for producing the same, which has a radio wave transmitting effect and is sufficiently transparent and highly safe.

[0019]

EXAMPLES The present invention will be specifically described below with reference to examples. However, the present invention is not limited to the embodiment.

Size 610 mm × 610 mm, thickness 5 m
The clear glass plate of m was washed with a neutral detergent, rinsed with water, isopropyl alcohol in that order, dried, and then set so that it could reciprocate upward against the Sn target set in the vacuum chamber of the DC magnetron sputtering device. Then, the inside of the tank is vacuum pumped at about 5 × 10 ⁻⁶ Tor.
After deaeration up to r, O ₂ gas and Ar gas (provided that the O ₂ gas concentration is in the range of 0 to 75%) are introduced into the vacuum chamber,
The degree of vacuum is maintained at about 2 × 10 ⁻³ Torr, a power of about 1 kW is applied to the Sn target, and a speed of about 100 mm / in a DC magnetron sputter with a mixed gas of O ₂ and Ar above the Sn target. By transporting the plate glass at min, about 200 to 20
Thin films of tin oxide containing oxygen defects of various thicknesses between 00Å were deposited. After the film formation is completed, the application to the Sn target is stopped.

In the obtained antistatic glass with a tin oxide thin film, the surface resistivity was first measured by a surface high resistance meter (HIRESTA HT-20, manufactured by Mitsubishi Yuka), and as an example, the film thickness was about 1000Å. Change in surface resistivity (Ω / □) when a film is formed by the sputtering method in an atmosphere in which the value of O ₂ / (O ₂ + Ar) is changed between 0% and 60%. Is shown in FIG.
Table 1 shows the surface resistivities (Ω / □) immediately after film formation at various oxygen gas concentrations (%) and after heat treatment of the above-mentioned coated thin film formed in air. Table 1
As is clearer, the surface resistivity is 10 ⁶ to 10 ⁹ Ω / □ when the film is heat-treated only under the above-mentioned film formation conditions or after the film formation is adjusted to a specific temperature and time in air. It could be a resistive thin film.

The charge elimination half-life, which is the static elimination performance, was measured by the static onest meter (manufactured by Shishido Electrostatics Co., Ltd.) described above, and the charge half-life of the antistatic glass surface was all in the range of 0.1 to 2 seconds. It was a thing. Furthermore, regarding these electrical characteristics, 25 ° C, 50% R
It is measured in a clean room in an H atmosphere.

Next, the visible light transmittance (380 to 780n
m), etc., the optical characteristics of the 340 type self-recording spectrophotometer (manufactured by Hitachi, Ltd.) and JISZ8722, JISR3106 are obtained by measurement and calculation. For example, when the visible light transmittance is 60% or more, 70-80% It has sufficient transparency, and the abrasion resistance of ABRASER MODEL 503 (TYBE
R, 200 rotations under a load of 250 g, and then measured by a digital haze meter (NDH-20D, manufactured by Nippon Denshoku Industries Co., Ltd.), and the value is, for example, 1% or less. The tin oxide thin film had an improved degree of damage resistance and excellent wear resistance.

Further, regarding the acid resistance test of the chemical resistance, it was judged by observing the deterioration state of the film after immersing the test piece in a 1N HCl solution at room temperature for about 6 hours. For the test, 1N NaO at room temperature
After the test piece was immersed in the H solution for about 6 hours, the state of deterioration of the film was judged and judged, and almost no deterioration was observed.

As mentioned above, the antistatic glass obtained had sufficient desired properties.

[0026]

[Table 1]

[0027]

As described above, according to the present invention, the outermost surface thin film of the tin oxide thin film containing oxygen defects at a specific film thickness is formed by the reactive DC sputtering method under the film forming conditions in a specific atmosphere. Efficiently and skillfully coat the surface of the glass plate, and if necessary, heat-treating the coated thin film in air,
It can be assumed that the surface resistivity of the coating itself can be specified as 10 ⁶ to 10 ⁹ Ω / □, and not only the transparency but also the light resistance,
Not only will it be more durable than weather resistance or chemical resistance, but it can also be used as a single plate in places where antistatic is required, for example, and it will exhibit the desired antistatic performance. In addition, it can be widely adopted in various fields.

[Brief description of drawings]

FIG. 1 is an example showing a relationship between an oxygen concentration in a film forming atmosphere and an insulation resistance value which is a surface resistivity in the antistatic glass of the present invention, when the film thickness of a tin oxide thin film is about 1000 Å.

Claims (6)

[Claims] 1. A laminated thin film coated on the surface of a glass plate, wherein the outermost surface thin film is a thin film formed by a reactive DC sputtering method, and the thin film is a tin oxide thin film having a thickness of 200 to 2000 Å. The surface resistivity of the tin oxide thin film is 1
An antistatic glass, which is a high resistance thin film of 0 ⁶ to 10 ⁹ Ω / □. 2. The tin oxide thin film has oxygen defects,
2. The antistatic glass according to claim 1, wherein the visible light transmittance is 60% or more, and the color tone of the transmitted light is colorless or light colored. 3. A laminated thin film-coated glass in a vacuum thin film laminating apparatus, in which a metallic tin target is set and the mixed gas of oxygen and argon is O ₂ / (O ₂ + Ar) = 0 to 75%. As the outermost surface thin film of the plate, the film thickness is 200 to 2000 Å by the reactive DC sputtering method.
The method for producing antistatic glass, characterized in that the tin oxide thin film is formed into a high resistance thin film having a surface resistivity of 10 ⁶ to 10 ⁹ Ω / □. 4. A laminated thin film-coated glass in a vacuum thin film laminating apparatus, in which a target of metallic tin is set and the mixed gas of oxygen and argon is O ₂ / (O ₂ + Ar) = 0 to 75%. As the outermost surface thin film of the plate, the film thickness is 200 to 2000 Å by the reactive DC sputtering method.
To form a tin oxide thin film having a surface resistivity of 10 ⁶ to 10 ⁹ Ω / □.
A method for producing an antistatic glass, characterized in that a heat treatment is performed in an air atmosphere at a treatment temperature of 100 to 500 ° C. 5. The mixed gas is O ₂ / (O ₂ + Ar) =
The antistatic glass according to claim 4, wherein when the film is formed in an atmosphere of 0 to 30%, a heat treatment is performed in the air at a processing temperature of 100 to 250 ° C after the film is formed. Law. 6. The mixed gas is O ₂ / (O ₂ + Ar) =
The antistatic glass according to claim 4, wherein when the film is formed in an atmosphere of 20 to 75%, a heat treatment is performed in the air at a processing temperature of 200 to 500 ° C after the film is formed. Law.