JP3280225B2 - Sol-gel thin film deposition method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a wet film forming method using a solution such as an alkoxide sol.
For example, a sol-gel thin film with a well-controlled thickness of about 2000 nm or less, particularly about 1000 nm or less, especially a base film, or a water-repellent film, an ultraviolet shielding film, an infrared shielding, a protective film, a transparent conductive film,
Various functional films such as photocatalyst film and colored film can be formed continuously, and high quality oxide thin film with uniform film thickness distribution over a large area with uniform film thickness distribution can be obtained with high efficiency. The present invention relates to a method for forming a useful sol-gel thin film that can be provided by the method described above.

[0002]

2. Description of the Related Art Conventionally, in a wet film forming method for forming a coating film on a substrate using a solution, for example, a dipping method in which the substrate is immersed in the solution and then pulled up at a constant speed, a solution is poured from above the substrate onto the substrate. There are various methods such as a flow coating method that spreads, a roll coating method that wets the rotating plastic roll surface with a solution and contacts the roll while transporting the substrate, and a spin coating method that drops the solution on the rotating substrate and flows it over the substrate by rotating force to spread it. Methods are known.

[0003] Among these methods, the above-mentioned flow coating method and roll coating method can form a coating film on one side of a substrate very easily. However, when an extremely thin film having a thickness of about 1 μm or less is to be obtained, for example. In the flow coating method, a large amount of solution must be constantly circulated in order to create a curtain of a wide range of solutions, and the solution is liable to change with time, such as an increase in solute concentration and an increase in viscosity. Since it is very difficult to adjust the contact degree (gap) of the substrate, when forming a thin film on a large-sized substrate, the obtained film thickness tends to vary from place to place, and a uniform film, particularly, for example, It is difficult to obtain an optical thin film or the like falling within ± 10%, and it is particularly difficult to control the film thickness on the order of submicrons, which is not suitable for forming an optical thin film or the like.

In a so-called reverse roll coating method in which the roll rotation direction and the substrate transfer direction are opposite to each other, for example, a relatively thick film having a thickness of about several μm or more can obtain a uniform film having a uniform thickness. Micron thin film,
In particular, it can be said that it is not an exaggeration to say that there is no practical example because it is difficult to obtain a good thin film with an optical thin film.

On the other hand, the above-mentioned dipping method and spin coating method have very excellent controllability of the film thickness, and are generally used, for example, as a method capable of controlling the film thickness on the order of submicrons. When a coating film is formed on both surfaces, it is necessary to cover the non-film-forming surface with a masking tape or the like to perform the film-forming operation. Although a coating film is formed with good controllability of the thickness, when the size of the substrate is large, a large-scale apparatus is required to rotate the substrate at a high speed, and the attachment / detachment of the substrate tends to be extremely complicated.

For example, Japanese Patent Publication No. Sho 60-52870 describes a method of forming a film, in which a film is formed on the surface of a substrate by rotation (revolution) in which a rotation center axis is located at a position other than the substrate. In the method, the substrate is rotated (rotated) around or around the central axis of the orbiting substrate, and is a flat substrate having a relatively small surface, for example, a diameter of 30.
mm or less.

[0007] For example, in Japanese Patent Application Laid-Open No. 3-65530,
A method for forming a film is described, and fine particles such as MgF ₂ and SiO ₂ sized to a particle diameter of 5 to 1000 nm are added to an alcohol solution of Si (OR) ₄ having R as an alkyl group. A method of forming a coating comprising spin-coating a liquid obtained on a glass surface and baking the liquid, wherein the liquid is spin-coated while the glass surface is inclined at an angle in the range of 10 ° to 60 °, and a cathode ray tube. It is described that the face surface may be sufficient.

[0008] For example, in Japanese Patent Application Laid-Open No. H5-24887,
A water-repellent treated glass is described, which has a transparent metal oxide film on the glass surface, and the surface of which is (1) CF _X H _Y or CCl _x H _y or a mixed gas thereof, or (2) ) Plasma etching in at least one gas selected from the group consisting of O ₂ , H ₂ , N ₂ O, CO ₂ and Ar gas, or in a mixed gas of (1) and (2) It has a description that it has fine irregularities provided by the above, and further has a water-repellent treatment layer thereon.

Among them, for example, in Example 1, ethoxysilane and hexylene glycol were dissolved in ethanol, reacted and cooled, then water and nitric acid were added, and the mixture was heated and reacted to form a sol-gel coating for film formation. 2 to 3 ml is dropped on a glass plate set on a spinner at 30 rpm at 3000 rpm.
Coat for 30 seconds, set for about 30 minutes,
It is described that a SiO ₂ film was prepared by baking for 30 minutes.

[0010] For example, Japanese Patent Application Laid-Open No. H5-120921 discloses that
A transparent conductive film and a method for producing the same are described.
It is described that a coating liquid containing an aluminum complex in which a ligand is coordinated to aluminum and ultrafine particles of a conductive oxide is applied to a substrate and cured, and for example, in Example 1, for example, The coating liquid is applied to the surface of the glass plate.
It describes that the coating was performed by a spin coat method at 750 rpm for 5 seconds.

[0011]

The above-mentioned method of forming a film described in, for example, Japanese Patent Publication No.
The method of forming a coating described in Japanese Patent No. 65530 is intended for a material having a relatively small surface area of about 30 mm or less in diameter or about the face surface of a cathode ray tube. Spin coating on large areas such as automotive window glass or architectural window glass by tilting the glass surface at an angle of 10 to 60 ° tends to be unstable and unsafe, and is not necessarily sufficiently uniform over a large area. Thus, it is difficult to form a film having no fringe (striped pattern due to light interference) phenomenon, and it is difficult to adopt it for glass having a very large area.

For example, in the water-repellent glass described in the above-mentioned Japanese Patent Application Laid-Open No. Hei 5-24887, a film on the surface of which fine irregularities are formed by etching is spin-coated, and the glass plate for a vehicle is not coated. It is not always possible to adopt a sufficient spin film formation for film formation that requires a high-precision film thickness that does not receive optical interference with a uniform film thickness distribution over the entire surface.

Furthermore, for example, in the transparent conductive film and the manufacturing method thereof described in the above-mentioned Japanese Patent Application Laid-Open No. 5-210921, there is still no uniform thickness distribution on the entire surface of a large-sized vehicle base plate and no optical interference. It is difficult to necessarily adopt a sufficient spin deposition for a deposition that requires such a highly accurate film thickness.

[0014]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has been made in consideration of the problem that a sol-gel solution is applied to a substrate by a spin coating method to form a thin film. By setting the spin film forming conditions of the comparatively fast spin rotation time, the time at which the spin rotation is stopped, and the relatively slow spin rotation time in an appropriate time series, for example, the organometallic compound is used as the main component. The sol-gel solution that has been prepared is simple, efficient in a relatively short time, and maintains the same level of film thickness controllability as dipping, regardless of the entire surface or almost the entire surface of a large-area substrate.
An optical thin film that suppresses fringe (stripes due to light interference (thickness unevenness), etc.) with a uniform film thickness distribution for thin films of about 2000 nm or less, especially about 1000 nm or less It is intended to provide a method for forming a thin film to be obtained.

[0015] That is, an automobile present invention, to be covered form a sol-gel film by spin coating on a glass substrate
In the method of film formation on window glass and architectural window glass plate ,
Set on spin coater and spin rotation speed is 50rpm
Viscosity of the solution on the surface of the substrate rotating at 500 rpm or less
Was added dropwise to about 0.1 to 50 centipoise film-forming coating solution prepared in, after coating the coating solution on the substrate surface, a spin rotation of the substrate before losing first flowable coating solution該被forming a film thirst the once stopped, then leveling the flow of the coating solution itself was coated reduction, then times while leveling
That the rolling speed to low speed below 100rpm or more 20rpm
Film thickness over or almost the entire surface of a larger substrate
A film with a uniform thickness distribution of 1000 nm or less is formed ,
Of fringe phenomena and liquid cracks at the four corners of the substrate
A method for forming a sol-gel thin film, wherein

Further, the organic gold of the coating solution for forming a film is used.
The method for forming a Rugel thin film as described above , wherein the concentration of the group compound is 0.1 to 10% by weight in terms of oxide .

Further, the film thickness is from 10 nm to a monomolecular layer.
A method for forming a sol-gel thin film as described above, comprising forming a thin film.

In an environment of 25 ° C. and a relative humidity of 45-70% RH
Coating film-forming, leveling and drying to film formation method of the sol-gel thin film described above, characterized in Rukoto.

Furthermore, the above-mentioned method for forming a sol-gel thin film , wherein the thin film is SiO ₂ —TiO ₂ .

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Here, a coating liquid for forming a coating is dropped on the surface of a substrate which is being set and rotated on the spin coater, and the coating liquid is coated on the surface by spin rotation. The spinning of the substrate is temporarily stopped before the coating liquid starts to dry and loses fluidity, leveling is performed by the flow of the coating liquid itself, and then a low-speed rotation with the leveling is performed to form a uniform coating As shown in FIG. 1, an optimum spin force (centrifugal force) matching the properties of the coating solution and the surface area of the substrate is exerted in the coating film area as shown in FIG. By establishing the leveling power of the liquid itself and the characteristics of the coating film, and by setting such as reducing the tact time and determining the characteristics of the coating film in the drying promotion area, the entire surface of a large-area substrate or almost the entire surface In any case, fringe phenomena with uniform thickness distribution for thin films of about 2000 nm or less, especially about 1000 nm or less, while maintaining the same level of film thickness controllability as simple and efficient in a relatively short period of time while maintaining dipping. Can be obtained, and an optical thin film without a film cracking phenomenon can be obtained.
This is a method of forming a sol-gel thin film which is much better than the conventional method.

Further, the spin rotation conditions during the film formation are as follows:
The reason that the rotation speed is 50 rpm or more and 500 rpm or less and the rotation time is 60 seconds or less is that if the rotation speed is less than 50 rpm, the spreadability of the coating liquid is deteriorated and a liquid cracking phenomenon occurs, In order to prevent the liquid cracking phenomenon, an excessive amount of the coating liquid is required, and waste is increased. On the other hand, when the rotation speed exceeds 500 rpm, when the size of the substrate is large, the instability of the spin rotation state increases, which is dangerous for the work, and when the same amount of the coating liquid is used, the film thickness decreases. In order to compensate, the concentration of the solute in the coating solution must be increased, resulting in an increase in loss, and with this, the difference in film thickness between the central portion and the peripheral edge tends to increase. The reason why the rotation time is further set to 60 seconds or less is that if the rotation time exceeds 60 seconds, drying of the coating solution proceeds excessively and the self-leveling property of the solution is reduced. Preferably, the spin rotation conditions during the film formation are a rotation speed of 70 rpm or more and 250 rpm or less and a rotation time of 30 seconds or less. More preferably the rotation speed is 100 rpm or more 20
The rotation time is 20 seconds or less at 0 rpm or less.

The reason why the time for temporarily stopping the spin rotation and for leveling is 20 seconds or more is as follows.
If the time is less than 2 seconds, the coating solution will be affected by the centrifugal force of the next rotation without proceeding with leveling and drying, and the solution will again approach the glass substrate end face, the film thickness distribution will increase, and film defects such as fringe phenomenon Will be generated. However, this time can vary greatly depending on the dilution solvent used for the coating solution. For example, methanol, ethanol, n-acetate
If the drying time is very fast, such as butyl, about 20 seconds may be used. Conversely, if the drying time is slow, such as butanol, about 60 seconds are required.

Furthermore, the condition for the low-speed rotation is that the rotation speed is 20 rpm or more and 100 rpm or less and the rotation time is 10 seconds or more. If the rotation speed is less than 20 rpm,
The effect of promoting the drying of the film is small, the meaning of promoting the drying of the film is meaningless, and if it exceeds 100 rpm, the drying time of the film will be shortened, but the fluidity of the liquid still remains at the beginning of rotation, Under the influence of the centrifugal force of the rotation, the liquid is again shifted to the end face of the glass substrate, the film thickness distribution increases, and a film defect such as a fringe phenomenon occurs. Further, the reason that the rotation time is set to 10 seconds or more is that if the rotation time is less than 10 seconds, the drying of the film is not completely completed, and the original purpose cannot be achieved.

The coating liquid is not particularly limited as long as it forms a sol-gel thin film. Examples of the coating liquid include Japanese Patent Application No. 7-294106 filed by the present applicant, A coating solution for a sol-gel thin film filed by a human being is preferred.

For example, it is stable to use a solution prepared such that the solid content of the coating solution is about 0.1 wt% to 10 wt% in terms of oxide and the viscosity of the solution is about 0.1 cP to 50 cP. This leads to excellent wear resistance, durability and optical characteristics.

The concentration of the organometallic compound, that is, the solute, in the solution for forming a film is set to about 0.1 to 10% by weight in terms of oxide. When the concentration is less than 0.1% by weight, for example, the supply amount of the solution and the rotation speed are changed. When trying to obtain the desired film thickness, not only does the film thickness distribution deteriorate and the variation increases, but also defects such as film breakage occur and the desired film thickness cannot be obtained. When the thickness is changed from 10 nm to a monomolecular layer film, it becomes difficult to become a practical thin film. When the thickness exceeds 10 wt%, cracks tend to develop in the thin film after firing, and it becomes difficult to obtain a stubborn thin film. This is because the film thickness distribution is non-uniform, and the variation does not become less than about ± 10%, but becomes considerably large, for example, about ± 60 to 80 nm or more. Preferably, it is about 0.5 to 7% by weight.

Further, the viscosity of the solution for film formation is 0.1 to
The reason for setting it to about 50 cP is that the film thickness distribution of the formed film can be made uniform, and for example, when it exceeds 50 cP, the solution for film formation cannot be spread evenly on the glass substrate and is difficult to spread. As a result, the uniformity of the film is reduced. It is preferably about 1 to 20 cP.

Furthermore, it is preferable that the baking of the coated glass sheet after the coating is appropriately performed, for example, by a process such as a heating bending process in a line and / or an air-cooling strengthening process.

Further, the substrate is a smooth inorganic transparent plate glass, which is not particularly limited to colorless or colored, and its kind or color tone. It can be used as various tempered glass or strengthened glass, a flat plate or a veneer, and can also be used as a multi-layer glass or a laminated glass. No.

As described above, in the sol-gel thin film forming method of the present invention, when a sol-gel solution is applied on a substrate by a spin coating method to form a thin film, the spin film forming conditions at the time of film formation are relatively fast. For example, a sol-gel solution containing an organometallic compound as a main component is applied to a large-area substrate by appropriately setting the spin rotation speed time, the time during which the spin rotation is stopped, and the relatively slow spin rotation time in a time series. For the whole or almost the whole of
Simple and efficient in a relatively short time, while maintaining the same level of film thickness controllability as dipping, without impairing the optical characteristics, fringe with a uniform film thickness distribution of about 2000 nm or less, especially about 1000 nm or less thin film [ It is an optical thin film that suppresses the phenomenon of light interference (stripe pattern due to uneven film thickness), has no film cracking (liquid-breaking) phenomenon, and has excellent stiffness and excellent wear resistance or durability. It is stable, reliable and free of troublesome processes, and can be manufactured with high quality and very high efficiency. It is especially excellent as an underlayer film, and furthermore, UV shielding film, antireflection film, heat ray reflection film, and certain types of passivation An object of the present invention is to provide a method for forming a useful sol-gel thin film which can be applied to the formation of thin films in various fields such as various functional thin films such as a water repellent film and a base film of a Nesa film.

[0031]

The present invention will be described below in detail with reference to examples. However, the present invention is not limited to such an embodiment.

Example 1 A green color tone float glass substrate having a size of about 1500 mm × 850 mm and a thickness of about 3.5 mm was washed with a neutral detergent, water rinse, and alcohol.
After sequentially cleaning with a filter and drying, the substrate was wiped with acetone to obtain a glass substrate for coating.

Tetraethoxysilane [Si (OC ₂ H ₅ ) ₄ : TEO
S] polymerized sol (average molecular weight Mv = about 1000-3000) and tetrabutoxytitanium [Ti (O
-Bu) ₄ ] (the content of tetrabutoxytitanium stabilized with acetylacetone is about 20 mol% in terms of oxide relative to SiO ₂ ) in isopropyl alcohol (iPA) , Butanol and ethanol alcohols
Solvent and add a solid concentration of about 5 wt% in terms of oxide.
The sol solution A was obtained by diluting until the solution became. [For example, CG19-Ti-1 manufactured by Daihachi Chemical Industry Co., Ltd.] Methyltrimethoxysilane [CH ₃ Si (OCH ₃ ) ₃ : MTMS] polymerized sol (average molecular weight Mv = about 1,000) was added to isopropyl alcohol. (IPA) was added and diluted to a solid content concentration of about 20% by weight in terms of oxide, to obtain a sol solution B.
[For example, MTS-2 manufactured by Daihachi Chemical Industry Co., Ltd.] About 2 g of the sol solution A and about 2 g of the sol solution B were mixed with butanol (n-n-butanol) for adjusting the rate of hydrolysis and dehydration condensation reaction. BuOH, moisture content 2000ppm, for example 150-3500ppm
Or 5500 g, 5000 ppm, 8000 ppm, etc.) About 9 g of the total and about 5 g are thoroughly mixed and stirred at about 50 ° C. for about 3 hours, and then 32.4 g of iPA (90
wt%) and 3.6 gn-BuOH (10 wt%) were diluted with about 36 g of a mixed solvent to obtain a coating solution. At this time, the solid content concentration was about 0.5 to 1.5 wt% in terms of oxide, and the viscosity was about 2 to 3 cP.

In the above description, the ratio of the sol solution A to the sol solution B is about 1: 4 by weight of the solid content, and more preferably, the ratio is about 1: 3.5 to 5.5. The stirring time after the mixing is, for example, preferably the stirring time is about
If the temperature is 50 ° C, it will be about 1-6 hours (honey stopper) to about 30 ° C
At a temperature of about 3 to 12 hours (honey plug).

Next, a glass substrate for coating is set on a spin coater, and the prepared coating solution is applied to the glass substrate for coating, for example, when the size of the front glass or rear window glass for automobiles. About 150-250ml
The amount of dripping, and also the side window glass for automobiles (for example,
Door glass, rear quarter, etc.)
It can be supplied onto the glass substrate for coating in a dripping amount of about 60 to 100 ml. However, the appropriate amount of application varies depending on the ratio of the length of the short side to the length of the long side of the glass substrate. For example, when the ratio is about 1: 1.75, about 160 ml / m ² is appropriate, and for example, When the ratio becomes about 1: 1, the appropriate value becomes smaller.

As for spin film forming conditions, as shown in FIG. 1, a raw glass of a rear window glass for an automobile, which is a glass substrate for a film, is set on a spin coater, and a coating film area (high-speed spin rotation) is first set. In, the spin rotation is started, the rotation speed becomes about 150 rpm (for example, about 50 to 250 rpm),
After 3 seconds, about 200 ml of the above-mentioned coating solution was dropped, and the rotation speed was maintained for about 19 to 17 seconds to form a film. Subsequently, in the leveling zone (stopping spin rotation), before the coated coating solution begins to dry and loses fluidity,
The spin rotation is temporarily stopped, and the sample is allowed to stand still for about 60 seconds and leveled. In the drying acceleration region (slow spin rotation), the spin rotation is started again, and about 50 rpm (eg, about 20 to 100 rpm).
(approximately pm) and maintained for about 40 seconds to promote drying and setting of the coating film. The coating was performed in an environment of about 25 ° C. and a relative humidity of about 45 to 70% RH, leveling time, drying acceleration and setting were performed, one cycle was completed, and a gel film was obtained with good film-forming properties.

Next, the glass substrate with the gel film was heated to about 250 ° C.
About 30 minutes in a large hot air circulating furnace, then calcining at about 740 ° C for about 4 minutes (actually about 10 seconds) in a muffle furnace to obtain a SiO ₂ -TiO ₂ thin film Was.
The solvent and organic substances are evaporated or decomposed in the pre-baking step to increase the film hardness, and furthermore, the organic substances, alkyl groups, alkoxyl groups, and the like are decomposed in the main firing, and the film strength is dramatically increased. .

The obtained glass substrate with a film was evaluated as follows. [Observation of surface shape of surface layer] Visual observation under a white fluorescent lamp. And AFM of scanning probe microscope (atomic force microscope)
Observed in a mode (Seiko Electronics, SP13700, 5 μm square scan or Olympus NV2000, 5 μm square scan), for example, average surface roughness Ra value (nm) [JIS B 06
This is a three-dimensional extension obtained by applying the center line average roughness Ra defined in 01 to the measurement surface, and can be expressed as "the average value of the absolute value of the deviation from the reference surface to the specified surface" (expression Is omitted)]. [Thickness measurement] Measured with DEKTAK (manufactured by Sloan). [Hardness measurement (wear resistance test)] Taber tester (taber
The increase ΔH in the haze value after 20 rotations with a worn wheel CS-10F was determined.

As a result, the thickness of the SiO ₂ —TiO ₂ thin film in the obtained glass plate with a film was, as shown in FIG.
For example, the film thickness distribution in the long side direction of the glass substrate (Example 1, solid line) is remarkably improved as compared with the conventional example (broken line), and the fluctuation width of the film thickness is greatly reduced. Excellent uniform film thickness distribution comparable to film formation by the dipping method.

FIGS. 3 and 4 show a comparison between the fringe (striped pattern due to light interference and the like) phenomenon portion in the present embodiment and the conventional example.
2 indicates a long side, 3 indicates a short side, 4 indicates a fringe phenomenon part, and 5 indicates a rotation center part. FIG. Such a fringe phenomenon part is shown in FIG.
It almost disappears to the extent that it is slightly left at the four corners of the glass substrate, has a remarkable improvement effect, and in this embodiment,
A glass sheet with a film that can be sufficiently used for practical purposes, such as eliminating the conventional liquid cracks 6 appearing at the four corners of the glass substrate as shown in FIG. This is a method for forming a sol-gel thin film aimed at by the present invention.

Further, for example, even when observed with an AFM, the average surface roughness Ra value is about 5 nm and the upper surface layer of fine irregularities is formed. It was a thin film having extremely good adhesion and hardness, and having remarkably good supporting and holding powers for a coating film and the like.

[0042]

As described above, according to the present invention,
A thin film having a uniform thickness distribution over a large area, particularly a fringe phenomenon, can be suppressed on only one side of a smooth substrate, and a thin film having a thickness of about 2 μm or less, particularly about 1 μm or less can be obtained, for example, at a low cost and significantly more efficiently. It has excellent adhesion, weather resistance, etc. without deteriorating its optical characteristics.It is suitable for certain protective films such as UV shielding films, antireflection films, underlayers, heat ray reflective films, so-called HUD films, etc. An object of the present invention is to provide a method of forming a sol-gel thin film, which is a useful oxide thin film and the like, which can be widely used and has high utility value.

[Brief description of the drawings]

FIG. 1 shows a sol-gel thin film forming method according to a first embodiment of the present invention.
The spin film formation conditions at spin rotation (rpm) and time (s
FIG. 4 is an explanatory diagram showing the relationship with ec) in a time-series manner.

FIG. 2 is an explanatory diagram showing a result of a film thickness distribution (solid line) under the spin film forming conditions (Example 1) shown in FIG. 1 in comparison with a film thickness distribution (broken line) of a conventional example.

FIG. 3 is a plan view showing a fringe phenomenon occurring on a film surface of a glass substrate with a film under the spin film formation conditions (Example 1) shown in FIG.

FIG. 4 is a plan view showing a fringe phenomenon generated on a film surface of a glass substrate with a film by a conventional spin film formation method.

FIG. 5 is a plan view showing a state of liquid cracks generated on a film surface of a glass substrate with a film by a conventional spin film formation method.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B05D 1/40 B60J 1/00 C03C 17/30 C23C 18/02

Claims (5)

(57) [Claims] 1. A motor vehicle window glass and building windows that the covering forms a sol-gel film by spin coating on a glass substrate
In a method of forming a film on a glass plate, the viscosity of the solution is set to about 0.1 to 50 cm on the surface of a substrate which is set on a spin coater and spins at a spin speed of 50 rpm or more and 500 rpm or less.
Was added dropwise film-forming coating liquid prepared in poise, after coating the coating solution on the substrate surface, once stops spinning of the substrate before losing first flowable coating solution該被forming a film is thirst, Leveling is performed by the flow of the coating solution itself, and then the rotation speed is 20 rpm or more 1 in the leveled state.
By rotating at a low speed below 00 rpm, large substrates
Uniform thickness of 1000 nm or less over the entire surface or almost the entire surface
A film with a film thickness distribution is formed and the four corners of the glass substrate are free
A method for forming a sol-gel thin film, characterized by preventing formation of a phenomenon phenomenon part and a liquid crack part . 2. The concentration of an organometallic compound in a coating solution for forming a film.
The method for forming a sol-gel thin film according to claim 1 , wherein the degree is 0.1 to 10 wt% in terms of oxide . 3. A thin film of a monomolecular layered film having a thickness of 10 nm.
Method of forming the sol-gel thin film according to claim 1 or 2 wherein, characterized in that formed. 4. Application in an environment of 25 ° C. and a relative humidity of 45-70% RH
Film-forming, film forming method of sol-gel thin film according to any one of claims 1 to 3, leveling and drying to said Rukoto. Method of forming the sol-gel thin film according to any one of claims 1 to 4, characterized in that wherein the thin film is a SiO ₂ -TiO _2.