JPH0741337A - Optical coloring prevention transparent body - Google Patents

Abstract

PURPOSE: To obtain a transparent body to prevent schillerization which can prevent color shading (schillerization) caused by an uneven thickness of a highly refractive transparent electrically conductive film and a change of viewing angle, irrespective of thickness of a substrate film.

CONSTITUTION: There is a mixed layer 12 between a transparent electrically conductive film 11 and a substrate film 13, which comprises components of the transparent electrically conductive film 11 and the substrate film 13. The transparent body to prevent schillerization is formed in such a way as the refractive index of the mixed layer 12 changes gradually between the substrate film 13 and the transparent electrically conductive film 11.

COPYRIGHT: (C)1995,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antiglare transparent body.

[0002]

2. Description of the Related Art Conventionally, a glass substrate having a transparent conductive film formed on the surface of the glass substrate has been used as an electrode for various displays and a low-emission glass plate. For example, a glass substrate having indium tin oxide (ITO) formed on the glass substrate by an ion plating method is often used as a transparent electrode of a display element such as a liquid crystal. A fluorine-doped tin oxide (SnO ₂ : F) film formed on a glass substrate by a spray method is widely used as a low-emission glass plate for a window glass of a house. Further, recently, the glass substrate on which the transparent conductive film is formed is considered to be a new application such as an electromagnetic shielding glass plate for construction, an electrically heated windshield glass for automobiles, and a transparent conductive substrate for consumer solar cells. It's starting to happen. All of these are applications requiring a large area glass substrate.

However, as the material forming the transparent conductive film,
There are ITO, fluorine-doped tin oxide (SnO ₂ : F), antimony-doped tin oxide (SnO ₂ : Sb), aluminum-doped zinc oxide (ZnO: Al), and the like, but all of these transparent oxide materials have a refractive index. Since it is 1.8 to 2.2, which is larger than that of glass, the reflectance at the wavelength satisfying the interference condition becomes large. That is, when these transparent oxides are formed on the glass substrate to a certain thickness or more, a maximum and minimum wave (ripple) appears in the spectral reflection (transmission) spectrum. Therefore, when these thin films are formed on a large-area glass substrate, the wavelength of the reflection (transmission) maximum shifts due to in-plane film thickness fluctuations (unevenness), which causes reflection (transmission) color irradiance, that is, color unevenness (iridence). Will be perceived by the eyes.

The film thickness distribution on the surface of the glass substrate depends on the film forming method. For example, when a glass plate of 1 m × 1 m is considered, a vapor deposition method, a sputtering method, a CVD method, an online spray method or the like. In the method according to (2), it is the current situation that an extremely high technology is required to suppress the amount within ± 5%. According to our research, assuming this thickness distribution,
When the transparent conductive film is formed on a glass substrate with a thickness of about 0.15 μm or more, in-plane color unevenness reaches a problematic level. On the other hand, as the film thickness is increased, the saturation of the reflected (transmitted) color begins to decrease. The vividness decreases with a thickness of about 0.6 μm or more, but a film thickness of 3 μm or more, preferably 5 μm or more is required to exceed the level of discrimination as color unevenness.

Further, even if the film thickness distribution can be controlled extremely uniformly, a large ripple remains in the spectral spectrum, so that a film having a film thickness of 3 μm or less is perceived as a vivid color. . When this is formed on a large-area glass substrate, the maximum reflection (transmission) wavelength shifts due to the angle (visual angle) formed by the surface of the glass substrate and the line of sight, and the color changes, so it is also perceived as color unevenness. Therefore, it is desirable to reduce the ripple itself in the spectrum. When the film thickness is thinner than 0.15 μm, the variation of the film thickness distribution is ±
Since the thickness is about 7.5 nm, the in-plane color unevenness due to the film thickness variation is hardly sensed, but the color unevenness due to the viewing angle is still a problem. When the transparent conductive film is formed to a certain thickness on the glass substrate as described above, color unevenness may be observed on the glass substrate due to in-plane film thickness variation and change in viewing angle, which may significantly impair commercializability.

Several proposals have been made to prevent this. For example, Japanese Patent Publication No. 63-3953
JP-A No. 5 (1994) discloses a layer having a refractive index (n) of 1.7 to 1.8 between a transparent conductive film and a glass substrate and having a thickness corresponding to a quarter wavelength of visible light (at a wavelength of 500 nm). A method of forming is shown. Further, in the publication, the refractive index (n) between the transparent conductive film and the glass substrate is 1.6 to 1.7, and the thickness corresponds to ¼ wavelength of visible light (at a wavelength of 500 nm). And the refractive index (n) = 1.8 to 1.9.
That is, a method of continuously forming a layer having a thickness corresponding to ¼ wavelength of visible light in the above order from the two-layer glass substrate side is shown.

Further, in JP-A-1-201046, n = 1.7-1..n is provided between the transparent conductive film and the glass substrate.
A method of forming a SiC _x O _y film is disclosed as a practical means for forming the layer No. 8. Assuming that the float method is used as a method for producing sheet glass, a mixed gas of silane, an unsaturated hydrocarbon compound and carbon dioxide is applied to the glass ribbon surface in a molten metal kiln such as tin. It is a method of forming a transparent film having an intermediate refractive index between the plate glass and the transparent conductive film by the method.

In any case, the film thickness of the underlying layer of the transparent conductive film is 1 / visible light (at a wavelength of 500 nm).
At least a film thickness corresponding to four wavelengths is required. Therefore, in any case, the atmospheric pressure CVD method is described as an example as a forming means. It is said that the film formation by the atmospheric pressure CVD method or the online spray method is a very advantageous method especially in terms of cost when a large number of glass plates are continuously processed in the manufacturing process. However, as described above, on the other hand, these methods make it very difficult to precisely control the film thickness within the glass plate surface. Is difficult to do.

In many cases, the transparent conductive film has a semiconductive property. On the other hand, soda-lime-silicate glass containing an alkali component is often used for the glass substrate, but when sodium in the glass enters the transparent conductive film, its conductivity and low radiation performance are remarkably increased. descend. The base film provided between the transparent conductive film and the glass is
It also has the effect of suppressing the entry of sodium ions and other alkali ions into the glass (so-called alkali inhibition), but in order to make the effect sufficient, it is desirable that the film thickness is thicker.

On the other hand, according to the disclosures of JP-A-63-39535 and JP-A-1-201046, the silicon oxynitride coating and the silicon oxycarbide coating serve as good barriers for sodium ions, and the alkali blocking is 1 / 4
It is stated that a film thickness corresponding to the wavelength is sufficient,
When forming these films, a silane-based compound, which is highly dangerous, is often used as a raw material for the reason of forming the film, which may cause a safety problem in manufacturing. Therefore, when another material is used, if the underlayer is made thicker to obtain the alkali barrier effect, there is a drawback that the effect of preventing iris is lost.

[0011]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems and provides a transparent body which can easily achieve the prevention of iris regardless of the thickness of the underlying film provided under the transparent conductive film. It is intended to be newly provided.

[0012]

The present invention has been made to solve the above-mentioned problems, and has a transparent conductive film on a transparent substrate, and between the transparent substrate and the transparent conductive film. In a transparent body having a base film, a mixed layer composed of constituent components of the transparent conductive film and the base film is interposed between the transparent conductive film and the base film, and the mixed layer is the base film. And a transparent conductive film, wherein the refractive index is gradually increased from the side closer to the base conductive film to the side closer to the transparent conductive film. To do.

According to the present invention, the condition for iris prevention can be greatly relaxed by gradually changing the refractive index between the transparent conductive film and the underlayer film for iris prevention.

As the transparent substrate in the present invention, ordinary plate glass, float glass plate, other various glass substrates,
Although a plastic film, a plastic substrate or the like can be used, the scope of the present invention is not limited to these. Examples of the transparent conductive film of the present invention include Sn-doped indium oxide film (ITO), F-doped tin oxide film (SnO ₂ : F), and Sb-doped tin oxide film (SnO ₂ : Sb). , Al-doped zinc oxide film (ZnO: Al), Ga-doped zinc oxide film (ZnO: Ga), etc. are used as typical ones, but the scope of the present invention is not limited thereto. is not. The transparent body on which the transparent conductive film is formed can be used as a heat mirror glass plate for construction, a low radiation glass plate, an electromagnetic shielding glass plate, an electrically heated windshield glass plate for automobiles, an ultraviolet cut glass plate and the like. The thickness of the transparent conductive film is set so as to obtain a desired resistance value, low radiation performance, heat ray reflection performance, electromagnetic shielding performance, electric heating performance, etc., but is usually about 0.03 μm to 1.0 μm. In particular, in the mixed layer, in particular, a layer portion having a refractive index equal to or higher than the average value of the refractive index of the transparent conductive film and the refractive index of the underlying film, and the same refractive index as the transparent conductive film. When the thickness of the layer portion, which is the sum of the layer portion having the film thickness and the layer portion having, is regarded as the substantial film thickness of the transparent conductive film, the substantial film thickness of the transparent conductive film is 0.
When the thickness is 15 μm or more, the effect of the mixed layer on preventing iris is remarkable.

The base film of the present invention is aluminum,
Cerium, lanthanum, magnesium, silicon, zirconium at least one oxide, nitride, carbide, fluoride or a composite thereof, or a composite oxide containing SiO ₂ as a main component, for example, SiC _x O _y , SiN _x. O _y
Etc. are used as typical examples, but the scope of the present invention is not limited thereto. Especially considering the price and durability, Al ₂ O ₃ or its composite oxide,
Alternatively, a composite oxide containing SiO ₂ as a main component, such as Si
_{C x O y, SiN x O} y and the like are preferred. When manufacturing the above-mentioned architectural heat mirror glass plate, low-emission glass plate, electromagnetic shielding glass plate, and the like, the atmospheric pressure CVD method or online spray method is often used in the float glass manufacturing process. The above-mentioned SiC _x O _y and SiN _x O _y
In the case of forming the undercoat film, the silane compound in a gas state or a gas-liquid equilibrium state is often used as a raw material for the reason of film formation, but the silane compound is highly dangerous. Therefore, in consideration of safety, A
It is desirable to use 1 ₂ O ₃ or its composite oxide. As the film thickness of such a base film, maintaining transparency,
In addition, it is preferable that the thickness is sufficient to obtain a sufficient alkali barrier effect.

In particular, in the mixed layer, a layer portion having a refractive index less than or equal to the average value of the refractive index of the transparent conductive film and a refractive index of the underlying film, and a layer portion having the same refractive index as the underlying film. When the sum of the thicknesses is regarded as the substantial thickness of the base film, the substantial thickness of the base film is 0.04 μm to 0.20.
It is preferably in the range of μm.

The mixed layer in the present invention is composed of the components of the transparent conductive film and the underlying layer. For example, the transparent conductive film is a F-doped tin oxide film (SnO).
₂ : F) and the underlayer is made of Al ₂ O ₃ , the mixed layer is a layer containing both (SnO ₂ : F) and Al ₂ O ₃ and is formed on the transparent conductive film side. Is (Sn
O ₂ : F) rich layer, Al ₂ O ₃ on the underlayer side
It is a rich layer. And the refractive index of the mixed layer is
It is high on the transparent conductive film side and low on the underlayer side. For example, the refractive index of the mixed layer is about 2.0 on the transparent conductive film side and about 1.7 on the underlayer side, and the refractive index gradually decreases from the transparent conductive film side toward the underlayer side in the meantime. is doing. The thicker the mixed layer, the higher the effect of preventing iris, but the preferable substantial thickness of the underlying film is 0.40 μm at the maximum because of the above-mentioned restrictions.
The following is preferable.

For such a mixed layer, for example, a rotary shutter having two holes formed by a binary vapor deposition method is used, and the shutter is gradually rotated during vapor deposition so that atoms or atoms reaching the substrate from each vapor deposition source can be used. It can be formed by a method such as controlling the number of molecules. In forming each coating film relating to the present invention on the transparent substrate, not limited to the vacuum deposition method, a spraying method, a chemical film forming method such as a CVD method, a sputtering method, a physical film forming method such as an ion plating method,
Other various film forming methods can also be used.

[0019]

[Function] In the first place, the cause of the appearance of iris, that is, color unevenness is
This is the interference effect of light at the upper and lower interfaces of the high refractive index thin film when a transparent thin film having a sufficiently higher refractive index than the substrate is formed on the transparent substrate. Therefore, a maximum (minimum) (ripple) of reflectance (transmittance) occurs in the spectrum. Here, when the film thickness of the high refractive index thin film is changed, the positions (wavelengths) of the maximum and minimum are changed, and it is observed that the color tone is changed. Alternatively, when the viewing angle is changed, the positions (wavelengths) of maximum and minimum in the spectrum are similarly changed, and the change in color tone is observed.

One of the anti-glare methods described in JP-B-63-39535 is to reduce the magnitude of ripples by providing an anti-reflection layer having an optical film thickness of 1/4 wavelength. By doing so, it is intended to prevent glow. The mixed layer in the present invention has the effect of widening the range of the iris prevention condition of the undercoat film, and thus, the iris effective even when the undercoat film thickness deviates from the value described in JP-B-63-39535. The prevention effect can be retained.

2 to 4 show that the film thicknesses of the underlying films having a refractive index of 1.7 are 50, 100 and 200 nm, respectively.
The thickness of the transparent conductive film having a refractive index of 0 is 250 nm to 5 nm.
The change in the reflected color when the thickness is changed to 00 nm is calculated and shown on the CIE chromaticity coordinates. The thickness of the mixed layer is 40 nm and 80 nm without the mixed layer.
The case was calculated. The refractive index of the substrate at this time was calculated as 1.515. In addition, in this calculation, comparison was made by making the total film thickness the same in the case where there is no mixed layer and the case where there is a mixed layer. For example, when comparing a structure having no mixed layer and a transparent conductive film of 400 nm and an underlying film thickness of 100 nm with a mixed layer of 40 nm, the transparent conductive film at that time is 380 nm and the underlying film thickness is 80 nm, each of 20 nm. The calculation was performed so that the total film thickness would be the same as when there was no mixed layer, by decreasing the value by each. 2 to 4
Therefore, as the thickness of the transparent conductive film changes, the reflection color draws an arc around the light source color and gradually approaches the light source color. The thickness of the base film is 50 nm, 100
It can be seen that the reflected color becomes more neutral by having the mixed layer even when the values are largely deviated from the antireflection condition (81 nm) of nm and 200 nm. Further, it can be seen that the reflected color is more neutral when the thickness of the mixed layer is 80 nm than when the mixed layer is 40 nm.

[0022]

【Example】

Example 1 A film was formed on a ribbon of 6 mm float glass by an online spray method. Al (NO ₃ ) ₃ and Sn (NO ₃ ) ₄ were used as raw materials, respectively, and were 10: 0, 9: 1,
11 kinds of solutions dissolved in ethanol were prepared while heating at a ratio of 8: 2 ... 0:10, and left standing at room temperature for 2 days and nights.
Arrangement of the spray nozzle is parallel to the flow direction.
10 pieces were arranged in a direction perpendicular to the flow direction. When the float glass ribbon from the float bath is at 650 ° C,
The ratio of Al (NO ₃ ) ₃ and Sn (NO ₃ ) ₄ is 10: 0.
The above raw material was sprayed onto the ribbon from a nozzle to form a film of aluminum oxide having a thickness of 80 nm. Next, Al (NO ₃ )
The raw material in which the ratio of ₃ and Sn (NO ₃ ) ₄ is 10: 0 is supplied from the nozzle next to the lower nozzle, and further from the lower nozzle to Al (NO 3
_{3) 3} and Sn (NO _{3) 4} ratio 9: 1 of the raw material, hereinafter, Al (NO ₃ from the upstream side) ₃ and Sn (NO _{3) 4} ratio respectively 8: 2, 7: 3 ... Nine kinds of raw materials of 0:10 are set and sprayed at the same time, and the directions and positions of the nozzles are adjusted so that the raw materials sprayed from the neighboring nozzles overlap each other on the substrate, and the mixed layer is 40n.
m was formed into a film. Next, Al (NO ₃ ) ₃ and Sn (NO ₃ ) ₄
Was sprayed from the nozzle onto the ribbon to form a fluorine-doped SnO ₂ film having a thickness of 400 nm. The refractive index of the sample manufactured by this method was 1.7 for the aluminum oxide film and 2.0 for the SnO ₂ film. The spectral reflection spectrum of this sample is as shown in FIG.

Example 2 Next, similarly to the method of Example 1, the film thickness of the aluminum oxide film was 60 nm and the film thickness of the fluorine-doped SnO ₂ film was 3 nm.
A sample having a thickness of 80 nm and a mixed layer thickness of 80 nm was prepared, and the refractive index was measured in the same manner. As a result, the aluminum oxide film was 1.7 and the SnO ₂ film was 2.0. The spectral reflection spectrum of this sample is as shown in FIG.

Example 3 A glass substrate that had been thoroughly washed and dried, Al ₂ O ₃ on a hearth, and SnO ₂ and Sb ₂ O ₅ raw materials on another hearth prepared in the same bath. After being set in a vacuum chamber and evacuated to 5 × 10 ⁻⁶ Torr, by an EB vapor deposition method while introducing O ₂ gas near the glass substrate,
40 nm of aluminum oxide was vapor-deposited. Next, Al ₂ O
The power of the EB power supply of ₃ is gradually reduced and at the same time SnO
_The mixed layer was formed while increasing the power of the EB power source of ₂ and Sb ₂ O ₅ , and the film thickness was set to 40 nm. Then SnO ₂
And Sb ₂ O ₅ EB power supply only, antimony-doped Sn
An O ₂ film was formed to a thickness of 400 nm. The samples prepared by this method have a refractive index of 1.7 for the aluminum oxide film and Sn, respectively.
The O ₂ film was 2.0. The spectral reflection spectrum of this sample was almost the same as the spectrum shown in FIG. Then, in the same manner as above, the thickness of the aluminum oxide film is 60 nm and the thickness of the antimony-doped SnO ₂ film is 38 nm.
A sample having a thickness of 0 nm and a mixed layer thickness of 80 nm was prepared.
Similarly, when the refractive index was measured, the aluminum oxide film was 1.7 and the SnO ₂ film was 2.0. The spectral reflection spectrum of this sample was almost the same as the spectrum shown in FIG.

Comparative Example The thickness of the aluminum oxide film was set to 1 by the same method as in Example 1.
00 nm, the film thickness of fluorine-doped SnO ₂ is 420 nm
As a result, a film having a structure without a mixed layer was obtained. The refractive index of the film thus produced was 1.7 for the aluminum oxide film and 2.0 for the fluorine-doped SnO ₂ film. The spectral reflection spectrum of this film is as shown in FIG. Compared with the curves shown in FIG. 5 and FIG. 6, the ripple was slightly larger, and the film with the mixed layer had a significantly reduced chromatic color compared with the film without it.

[0026]

As is clear from the above examples, the present invention has the effect of widening the range of antireflection conditions necessary for preventing iris. For example, when the thickness of the base film cannot be strictly controlled, when it is desirable to make the base film thicker to suppress the entry of alkali ions from the glass substrate, and when it is desired to make the base layer thinner to further improve the productivity. Providing a mixed layer has a remarkable effect. In particular, a silica-based underlayer formed from a silane-based gas, which presently poses a safety problem, is used as an alkali barrier layer from a glass substrate, but an alkali barrier effect is produced by increasing the thickness of the underlayer. In that case, there is an effect that it is possible to use other materials, and it is possible to select a material that does not pose a safety problem.

[Brief description of drawings]

FIG. 1 is a sectional view of a transparent body having a film structure of the present invention.

FIG. 2 is a diagram showing the influence of the mixed layer on the chromaticity change when the transparent conductive film thickness is changed.

FIG. 3 is a diagram showing the influence of the mixed layer on the chromaticity change when the transparent conductive film thickness is changed.

FIG. 4 is a diagram showing the influence of the mixed layer on the chromaticity change when the transparent conductive film thickness is changed.

FIG. 5 is a spectral characteristic diagram of the antiglare transparent body of Example 1 of the present invention.

FIG. 6 is a spectral characteristic diagram of an antiglare transparent body of Example 2 of the present invention.

FIG. 7 is a spectral characteristic diagram of an antiglare transparent body of a comparative example of the present invention.

[Explanation of symbols]

 10: transparent substrate 11: transparent conductive film 12: mixed layer 13: base film

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takuji Oyama 1150 Hazawa-machi, Kanagawa-ku, Yokohama, Kanagawa Asahi Glass Co., Ltd. Central Research Laboratory (72) Inventor Makoto Noshiro 1150, Hazawa-machi, Kanagawa-ku, Yokohama Asahi Glass Co., Ltd. In the Central Laboratory (72) Inventor Robert Terno Belgium 6218 Chimeon, Le, de, Manant 6 (72) Inventor Michel Annotio Belgium 5911 Jodhwany, Le, de, Chantreine 2 a

Claims (6)

[Claims] 1. A transparent body having a transparent conductive film on a transparent substrate and having an undercoat film between the transparent substrate and the transparent conductive film, wherein the transparent film is provided between the transparent conductive film and the undercoat film. A mixed layer composed of the constituent components of the transparent conductive film and the base film is interposed, and the mixed layer is located between the base film and the transparent conductive film from the side closer to the base film to the side closer to the transparent conductive film. An anti-glare transparent body, characterized in that it is formed so that the refractive index gradually increases as it goes down. 2. A layer portion having a refractive index which is equal to or higher than an average value of the refractive index of the transparent conductive film and the refractive index of the underlying film in the mixed layer, and the same refractive index as the refractive index of the transparent conductive film. The substantial film thickness of the transparent conductive film is 0.03 μm or more, when the thickness of the layer part including the layer part which is included is regarded as the substantial film thickness of the transparent conductive film. The antiglare transparent body according to claim 1. 3. The antiglare transparent body according to claim 1, wherein the transparent conductive film has a refractive index of 1.8 to 2.5. 4. The mixed layer has a layer portion having a refractive index less than or equal to an average value of the refractive index of the transparent conductive film and the refractive index of the base film, and the same refractive index as that of the base film. When the thickness obtained by adding the layer portion is regarded as the substantial film thickness of the underlying film, the substantial film thickness of the underlying film is 0.04 to 0.2.
The anti-glare transparent body according to any one of claims 1 to 3, which has a thickness of 0 µm or more. 5. The antiglare transparent body according to claim 1, wherein the underlying film has a refractive index of 1.6 to 2.0. 6. The antiglare transparent body according to claim 1, wherein the transparent base is a glass substrate.