JP3516186B2 - Window glass - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention has excellent antifouling and antibacterial properties.
The present invention relates to a novel window glass having a self-cleaning property suitable for a window glass having a deodorizing function, particularly a window glass for a building, or a window glass for a transportation vehicle such as an automobile and a train.

[0002]

2. Description of the Related Art The surface of buildings such as buildings and window glass for transportation vehicles such as automobiles and trains is contaminated by cigarette tar and oil mist coming out of the room, and dust and dirt easily adhere to the surface. Has become. As one of the countermeasures, it has been attempted to coat the surface of the glass body with a fluororesin or introduce fluorine into the glass itself to enhance the water repellency of the surface and to give it antifouling property, but the processing cost In addition to high cost, it is easy to clean oil stains and tobacco tars, it is not very effective in preventing adhesion itself, and after all there is no way but to increase the frequency of cleaning, so a fundamentally good solution is I couldn't find it.

On the other hand, conventionally, attempts have been widely made to remove and decompose pollutants and the like in the air by using a photocatalyst centered on titanium oxide (for example, Japanese Patent Laid-Open No. 6-3.
No. 85, JP-A-6-49677, etc.). An attempt was made to form a hydrogen semiconductor optical semiconductor electrode by attaching a 1 μm thick titanium oxide thin film to a quartz glass substrate by RF sputtering (Japanese Patent Laid-Open No. 44053/1985), and a photocatalyst powder was applied to the surface of a glass tube for a discharge lamp. Attempts have been made to provide a deodorizing effect (Japanese Patent Application Laid-Open No. 1-169866).
Also, an attempt has been made to attach a titanium oxide film to the surface of the spectacle lens by the ion plating method to decompose the surrounding malodorous components (Japanese Patent Laid-Open No. 223909/1990).

[0004]

Problems to be Solved by the Invention [Patent Document 1] Japanese Patent Application Laid-Open No. 1-169866
In the discharge lamp described in Japanese Patent Laid-Open Publication No. 2003-242242, an anatase type titanium oxide powder having a particle diameter of 500 angstrom is merely applied on the outer surface of the discharge vessel, and the light transmittance and wear resistance are inferior. Even if the applied titanium oxide powder is baked, it is obvious that only high temperature is required and only the one having poor optical transparency can be obtained. Therefore, the obtained photocatalytic effect was small, and the surface was powdery and the surface was highly uneven. Further, in the air purifying eyeglasses described in JP-A-2-223909, although a titanium oxide thin film is provided on the glass lens surface by a physical method such as an ion plating method, the identification of titanium oxide and the crystal structure of the thin film are performed. However, there is little disclosure of objective composition and data regarding the determination of deodorizing effect.

Further, conventionally, in order to obtain a practical level of photocatalytic action by forming titanium oxide in a thin film form, titanium oxide sol is sintered and formed on a substrate, or fine powder of titanium oxide is applied and baked together with a binder. It was thought that there was no other suitable method. However, in the former case, it is necessary to set the sintering temperature to a temperature higher than the glass softening point in order to obtain a film strength that can be practically used even if one having high activity and light transmittance to some extent is obtained. It was difficult to apply it to a glass body for use. Further, in the latter case, since the light transmittance is low due to the finely powdered titanium oxide, and the surface irregularities are severe, dirt and dust are likely to be attached as described above.

An optical semiconductor thin film formed by a physical film forming method such as a sputtering method is disclosed in JP-A-60-44053, which is formed on a quartz substrate for generating hydrogen as an optical semiconductor. Thus, it is unsuitable for the photocatalyst thin film for the purpose of the present invention for decomposing oils and fats applied to window glass for transportation vehicles and the like. Certainly, with a quartz substrate, even a thin titanium oxide thin film can be obtained with some activity, but it cannot be used as a window glass.

Further, since the conventional glass body with titanium oxide is made of powder or sol, it is substantially opaque and has low light transmittance, and the light from the outside of the window is a contaminant of the atmosphere. There is a drawback that it is difficult to reach the outermost surface of the titanium oxide layer inside the window, which is most likely to adhere. Therefore, the amount of light that can be used is much less than when a transparent titanium oxide thin film is attached, and the amount of pollutants decomposed is also small, and in addition, dirt and oil mist due to surface irregularities are easily attached. was there.

The present invention has been made under the above-mentioned background, and an oxidation which can obtain a sufficient photocatalytic action by utilizing this light transmission property while ensuring a sufficient light transmission property as a window glass. By providing a titanium thin film on the surface, it is possible to effectively decompose even fat and oil components in an amount that adheres in a normal living space and obtain a novel self-cleaning performance. It is intended to be provided.

[0009]

In order to solve the above problems, a window glass according to the present invention has the following constitution. (Configuration 1) Photocatalytic action on at least one surface of the glass plate
A glass for windows provided with a titanium oxide thin film having
The titanium oxide thin film is directly exposed to light having a wavelength of 550 nm.
It has a linear transmittance of 50% or more and is compatible with light with a wavelength of 365 nm.
And the linear transmittance is 50% or less,
The film thickness between the thin plate and titanium oxide thin film is 0.02-1μ
Window glass characterized by having a pre-coated thin film
It is. (Structure 2) The titanium oxide thin film is at least anatase
ZE crystal is included, and the film thickness is 0.1 to 5 μm.
The window glass according to the configuration 1, characterized in that
It (Structure 3) The titanium oxide thin film is made of silver, copper or zinc.
At least one additive selected from the group
Characterized by containing 0.05 to 5 atom% with respect to the atom
It is the window glass according to configuration 1 or 2. (Structure 4) The precoat thin film contains SiO ₂ as a main component.
Structure 1 characterized by being a thin film made of a material
A window glass according to any one of 3 to 4. (Structure 5) At least one layer of the pre-coated thin film is acid.
Material containing indium oxide and / or tin oxide as a main component
Structure 1 to 1 including a thin film made of
The window glass according to any one of 4 above.

[0010]

According to the above configuration 1, at least the glass plate is
Titanium oxide thin film with photocatalytic action was provided on one surface
A glass for windows, wherein the titanium oxide thin film has a wavelength of 55
The linear transmittance for 0 nm light is 50% or more, and the wave
The linear transmittance for light with a length of 365 nm is 50% or less
And a film between the glass plate and the titanium oxide thin film.
Providing a pre-coated thin film having a thickness of 0.02 to 1 μ
In, it allows to obtain a revolutionary self cleaning performance that decomposed effectively the extent of the amount of fat and oil components to be attached with sufficient optical transparency in particular normal living space while ensuring as glass windows I have to. Therefore, for example, when it is used as a window glass for a building or a transportation vehicle such as an automobile or a train, it is very difficult to remove the oil smoke, cigarette tar, etc. that adhere to these indoors. It adheres to the glass by outdoor light and at the same time decomposes and removes relatively easily, without any intervention,
It can be used as an epoch-making window glass that can automatically maintain the desired clean state at all times. Of course, since it has the ability to decompose even fats and oils components that are generally said to be extremely difficult to decompose, it also has antibacterial and deodorizing functions. In addition, a pleco coat is formed between the glass body and the titanium oxide thin film.
By providing a thin film, some of the components of the glass body
Titanium oxide thin film photocatalyst diffused and permeated into titanium oxide thin film.
It is possible to prevent adverse effects such as a decrease in action.
This also expands the range of choices for glass body materials.
It has become possible. Furthermore, it is possible to directly oxidize the glass body.
When forming a thin film of tin, the substance in the glass body is oxidized.
Even if it penetrates into a thin film of titanium, it has a charge separation function.
It is necessary to increase the film thickness of titanium oxide to the extent that it does not reach tongue.
It was necessary, but because it is no longer necessary, the glass body
Regardless of the material of the titanium oxide thin film thickness
It is possible to obtain sufficient photocatalytic action even if it is thin.
It was In addition, the thickness of the pre-coated thin film is 0.02
If it is ~ 1 μm, it can be used as a pre-coated thin film
Ensure sufficient transparency even when considering quality in general.
With the effect of preventing the penetration of inhibitory substances from the glass body
be able to. On the other hand, 0. Sufficient penetration is less than 02μm
The blocking effect cannot be obtained, and a film of more than 1.0 μm is formed.
However, there is no further advantage to the penetration prevention effect.
Not only that, the film forming operation becomes complicated, and depending on the material,
This is because it may not be possible to ensure transparency.

Here, as the amount of oil and fat generated,
For example, Electrochemistry and Industrial Physical Chemistry vol63 No.1 p11 (199
As described in 5), it is 0.1 mg / cm ² · day even in a place where an extremely large amount of fats and oils are expected to be attached, such as in the vicinity of the ventilation fan above the range of kitchens in ordinary households, and it is 0.1 mg / cm ² · day. The amount of tobacco tar and tar contamination is 1 μg / c
Since it is reported to be less than m ² · day, it can be said that the value of 0.5 μg / cm ² · Hr is a sufficient value as the estimated amount of oil and fat to be attached when considering a normal living space. . Further, it can be said that a foul-smelling component contained in a small amount in the indoor space and various bacteria floating in the indoor space can be easily decomposed and killed if they adhere to the surface of the self-cleaning window glass according to the present invention.

According to the structure 2, the titanium oxide thin film is
At least include anatase crystals, and
By having the thickness of 0.1 to 5 μm , sufficient photocatalytic activity is obtained, and at the same time, the linear transmittance for light with a wavelength of 550 nm is 5
A titanium oxide thin film having 0% or more is obtained. in this case,
If the film thickness is less than 0.1 μm, sufficient photocatalytic activity cannot be obtained. Further, if the film thickness exceeds 5 μm, the linear transmittance for light having a wavelength of 550 nm is less than 50%, and sufficient transparency cannot be ensured, which is not preferable.

[0013]

According to Structure 3 , silver is formed on the titanium oxide thin film,
By adding at least one additive selected from the group consisting of copper and zinc in an amount of 0.05 to 5 atomic% with respect to titanium atoms, it is possible to improve catalytic activity, particularly deodorizing property and antibacterial activity. It is possible. These additives can be added by various addition methods, but as a method for uniformly adding a trace amount of additives, the photoreduction method by photocatalysis is the easiest and excellent in this case. As a result, for example, in the case of adding silver, there is an advantage that the antibacterial activity can be maintained high not only when light is irradiated, but also when light is not irradiated. Can be reduced to facilitate the adsorption of even acidic substances on the surface, which is advantageous for their decomposition and removal.

[0015]

[0016]

When the precoating thin film is usually made of a material containing SiO2 as the main component as in the constitution 4 , the glass body serving as the base body can ensure the best transparency and the substance permeation inhibiting effect.

According to the structure 5 , since at least one layer of the precoat thin film contains a thin film made of a material containing indium oxide and / or tin oxide as a main component,
It is possible to impart an electromagnetic wave shielding function to this glass body not only by the substance permeation-preventing effect from the glass body of the same substrate as the SiO2 thin film, but also by the conductivity derived from the indium oxide and / or tin oxide thin film. In general buildings, such as buildings, it is said that electromagnetic waves from the outside are the most common invasion route through the window glass, and it is extremely valuable to give window glass an electromagnetic wave shielding function along with self-cleaning properties. Can be said.

[0019]

DETAILED DESCRIPTION Reference Example 1 FIG. 1 is a sectional view of a window glass according to Reference Example 1 of the present invention. Hereinafter, the window glass of Reference Example 1 will be described with reference to FIG.

In FIG. 1, soda lime glass was used for the glass plate 1 serving as the substrate. That is, the titanium oxide thin film 2 is formed on one surface. Titanium oxide thin film 2
Is a titanium oxide thin film containing anatase crystals and having a thickness of 4.7 μm. This was created as follows.

First, width 15 cm, length 20 cm, thickness 1
mm soda lime glass plate 1 is set in the pyrosol film forming apparatus and titanium tetraisopropoxide 0.5 mo is used.
A raw material solution prepared by dissolving 1 of 1 l in acetylacetone was ultrasonically atomized, introduced into the above apparatus at 20 ml / min, and formed into a film at 500 ° C. for about 80 minutes to give a film thickness of 4.7 μm on the glass plate 1. The titanium oxide thin film 2 was formed. When a part of this glass plate was cut and the thin film was observed by thin film X-ray diffraction analysis, it was found to contain anatase crystals.

Next, the activity of decomposing fats and oils, which is an index of the antifouling function, and the linear transmittance of light, which is an index of transparency, of the glass plate provided with the titanium oxide photocatalyst thin film obtained were measured by the following method.

Antifouling Function Measuring Method As an index of the antifouling function, a commercially available salad oil containing linoleic acid as a main component was decomposed. The surface of a glass plate provided with a titanium oxide thin film was thinly coated with paper so that the salad oil was 0.1 to 0.15 mg per cm ² . The coating amount was determined by measuring the weight before and after coating. At least 300-4
After irradiating and irradiating the surface of the glass plate with 5 mW / cm ^{2 of} ultraviolet light including a part of the light of 00 nm, the weight of the glass plate at a predetermined time was calculated in order to obtain the relationship between the elapsed time and the weight change amount. It was measured with a precision balance and used as an index of decomposition activity.

Measurement of linear transmittance of light A part of a glass plate having titanium oxide was cut to obtain a width of 10 m.
A sample having a length of m and a length of 20 mm was prepared. Prepare a similar sample with a glass plate without titanium oxide, and measure the linear transmittance for light with wavelengths of 550 nm and 365 nm with a Shimadzu UV-3100PC spectrophotometer, with one side being the sample side and the other side being the reference side. did.

The result of the measurement by the above-mentioned method shows that the salad oil decomposition activity is 12.5 μg / Hr. cm ² , wavelength 550 nm
The linear transmittance with respect to the light was 75%, and the linear transmittance with respect to the light having a wavelength of 365 nm was 10%, and it was confirmed that it has excellent fat and oil decomposing activity and sufficient transparency.

Further, from the back surface of the glass plate provided with the titanium oxide thin film, a black light FL1 which is an ultraviolet lamp.
0BLB (trade name of Toshiba Lighting & Technology Co., Ltd.) was used to adjust the light irradiation intensity of the titanium oxide thin film surface to 5 mW / cm ² by irradiating light, and the salad oil degrading activity was examined in the same manner. Almost the same, 11.7 μg / H
It was confirmed that a fat-decomposing activity of r · cm ² was obtained. This indicates that when the titanium oxide photocatalyst film according to the present invention is attached to one surface of the glass plate, not only the light from the surface on which the titanium oxide film is attached, but also the light from the back surface can be sufficiently utilized.

< Reference Examples 2 to 4 > As in Reference Example 1 , except that the thickness of the titanium oxide thin film was changed, the titanium oxide thin film had the same structure as that of Reference Example 1 and was manufactured by the same method. reference
Examples of film thickness, the salad oil decomposition activity measurements and light linear transmittance measurement results, and detailed descriptions thereof will listed in the table in FIG. 2 will be omitted.

As shown in the table of FIG. 2, it can be seen that each of the examples has excellent fat and oil decomposing activity and sufficient transparency.

< Examples 1 to 3 > These examples are shown in FIG.
Similar manner between the titanium oxide thin film 2 and the glass plate 1 in Reference Example 1 as indicated, in addition to the pre-coated film made of SiO ₂ film formed by dip coating is constructed like the reference example 1 in Since it was manufactured in the above, the film thickness of each example, the fat and oil decomposition activity measurement result, and the light linear transmittance measurement result are listed in the table of FIG. 2 and the detailed description thereof is omitted.

As shown in the table of FIG. 2, as compared with Reference Examples 1 to 4 in which the pre-coated thin film layer was not provided, even if the titanium oxide thin film was thinned, excellent fat-and-oil decomposition activity was exhibited, so that higher transparency was obtained. It turns out that you can secure.

Example 4 In this example, silver is added to the titanium oxide thin film 2 of Example 3 . A glass plate on which a titanium oxide thin film was applied in the same manner as in Example 3 until the film thickness became 3.0 μm, width 10 cm, length 15 cm,
Place in a glass container with a depth of 1 cm and prepare a 1% silver nitrate aqueous solution 3
0 ml was added, and a 400 W high-pressure mercury lamp was irradiated for 40 minutes to deposit a small amount of metallic silver on the titanium oxide thin film by photoreduction. The amount of silver deposited was determined by the SEM-EDS method, and the results of the salad oil decomposition activity measurement and the linear light transmittance measurement were shown in FIG.
Tables are listed together.

< Embodiment 5 > In this embodiment, Embodiments 1 to 1
In the same manner as in No. 3, a pre-coated thin film made of a SiO ₂ film was formed between the titanium oxide thin film 2 and the glass plate 1 by dip coating, and a second pre-coated thin film was formed on the indium oxide containing 8% tin oxide. Thin film (IT
The pre-coat thin film having a thickness of 0.2 μm is formed by the above-mentioned pyrosol device, and then the titanium oxide thin film is provided by the same method as in Reference Example 1. , And the fat and oil decomposition activity measurement result and the light linear transmittance measurement result are listed in a table in FIG. 2 and the detailed description thereof is omitted.

[0033] As can be seen from the table of FIG. 2, Example 1
Similar to the case of 3, a thin film having a higher salad oil decomposing activity than that of the titanium oxide thin film having no precoat layer was obtained. In addition, in the case of Example 5 , since the transparent conductive film was pre-coated, the electromagnetic waves passing through the glass plate were weakened, and the adhesion of dust due to static electricity was reduced.

Comparative Example 1 This comparative example has the same structure as that of Reference Example 1 except that the thickness of the titanium oxide thin film 2 in Reference Example 1 is reduced to 0.05 μm, and is manufactured by the same manufacturing method. Therefore, the film thickness, the fat and oil decomposition activity measurement result, and the light linear transmittance measurement result of this comparative example are shown in a table in FIG. 2 and the detailed description thereof is omitted.

As shown in the table of FIG. 2, in this comparative example, the transparency is good, but the fat and oil decomposing activity is hardly exhibited.

[0036] <Comparative Example 2> The comparison example, in addition to changing the temperature for forming the titanium oxide thin film 2 in Reference Example 1 in 360 ° C. in the same manufacturing method has the same configuration as in Reference Example 1 Since it was manufactured, the film thickness of this comparative example, and the fat and oil decomposition activity measurement result and the light linear transmittance measurement result are shown in FIG.
It is listed in the table and its detailed description is omitted. In the case of a glass plate provided with this titanium oxide thin film, the titanium oxide thin film 2 contains no anatase crystals,
Confirmed by thin film X-ray diffraction.

The composition of the window glass used in the present invention is not particularly limited as long as it is a composition of a glass used for a window glass of a normal building and a window glass of transportation equipment such as an automobile and a train. Absent.

When the glass plate of the substrate is soda lime glass or the like, the fat and oil decomposing activity of the titanium oxide thin film is inhibited by the alkaline component such as sodium diffusing from the substrate. It is desirable to provide a pre-coated thin film on. As a result, it is possible to advantageously use inexpensive glass such as soda lime glass in which alkali components may diffuse.

The titanium oxide thin film has a thickness of 0.1 μm to 5 μm.
If it is less than 0.1 μm, it is transparent but its activity is low, so that it is not practical, and if it exceeds 5 μm, the activity can be maintained high and coloring due to light interference is reduced, but the film is However, defects such as peeling of the film and a long film forming time tend to occur.

Further, the film thickness of titanium oxide to be formed is made large, for example, 0.3 μm to 5 μm, the concentration of sodium in the titanium oxide thin film is gradually decreased, and titanium oxide in the vicinity of the thin film surface is utilized as a photocatalyst. It is also possible, in which case the pre-coated thin film can be omitted.

The pre-coated thin film has a thickness of 0.02 μm to 1 μm.
If it is less than 0.02 μm, the ability to prevent alkali diffusion is low, and if it exceeds 1 μm, the ability to prevent alkali diffusion is not hindered, but the light transmittance is lowered and the film forming conditions are complicated, which is not preferable. By providing a pre-coated thin film, diffusion of alkali components such as sodium from the substrate can be prevented, so that the titanium oxide thin film can be made thinner, and it has a self-cleaning property with high transparency in the visible light region. Glass can be obtained.

The composition of the pre-coated thin film is not limited as long as it has a high visible light transmittance and is capable of suppressing the diffusion of sodium from the substrate. For example, a SiO ₂ thin film, a tin oxide thin film, an indium-added tin oxide thin film, an oxide film can be used. Indium thin film, tin-doped indium oxide thin film, germanium oxide thin film, alumina thin film, zirconia thin film, SiO ₂ + MOx
(MOx is P ₂ O ₅ , B ₂ O ₃ , ZrO ₂ , TiO ₂ ,
At least one kind of metal oxide selected from Ta ₂ O ₅ and Nb ₂ O ₅ ) thin film can be mentioned as an example, but from the viewpoint of alkali diffusion preventing ability, it is a silicon oxide thin film or SiO ₂ containing P ₂ O. ₅ was added about 5 wt% film is particularly desirable.

When a conductive thin film is provided in one layer of the pre-coated thin film to impart an electromagnetic wave shielding function, a tin oxide thin film, an indium-added tin oxide thin film, and an oxide having both transparency to visible light and conductivity are provided. An indium thin film, a tin-added indium oxide thin film, and the like are preferable, and among them, an indium oxide transparent thin film containing 5 to 10% tin oxide is preferable because it has a high visible light transmittance and excellent conductivity.

Furthermore, the necessary condition for obtaining a titanium oxide thin film having a high photocatalytic activity is that at least an anatase crystal must be contained. Since the anatase crystal undergoes a phase transition at a high film forming temperature or a high heat treatment temperature after the film formation and a part thereof changes to a rutile crystal, a titanium oxide thin film of anatase crystal containing a rutile crystal is also suitably used. However, if all the anatase crystals are converted to rutile crystals at high temperature, the titanium oxide thin film becomes cloudy due to the phase transition, which reduces the visible light transmittance, which is not preferable.

In the present invention, as the film forming method of the titanium oxide thin film and the pre-coated thin film, all the film forming methods which are usually used can be used. That is, the chemical vapor deposition method (C
VD method), spray method, spraying method of sol solution, pyrolysis method of thermally decomposing mist by ultrasonic waves, dip method, spin coating method, printing method, etc., as well as physical film forming method Various film forming methods such as a sputtering method, a vacuum evaporation method, an ion plating method, and a thermal spraying method using fine powder or sol can be adopted. Above all, considering the film formation on the window glass, the CVD method, the spray method,
A film forming method that can be incorporated into a window glass manufacturing process such as a pyrosol method is advantageous when industrial production is considered.
However, a film formation method that requires maintaining the substrate at a temperature higher than the glass softening point, for example, a temperature higher than 600 ° C. is preferable because it accelerates the deformation of the glass plate as the substrate and the diffusion of alkali components such as sodium from the substrate. Absent.

As a chemical agent for producing a pre-coated thin film,
The ones to produce a _{SiO 2, Si (OCH 3)} 4, Si (O
There are silicon alkoxides such as C ₂ H ₅ ) ₄ and SiCH ₃ (OCH ₃ ) ₃ and condensates thereof, and silicon halides such as SiCl _{4, and} as tin oxide-forming materials, Sn
(OCH ₃ ) ₄ , Sn (OC ₂ H ₅ ) ₄ , Sn (OC ₄ H ₉ ) ₄ , Sn
(AcAc) ₄ , Sn (OCOC ₇ H ₁₅ ) ₄ , SnCl ₄ , etc.,
In (OCH ₃ ) ₃ , which produces indium oxide,
_{In (OC 2 H 5) 3} , InCl 3, In (AcAc) 3, In (NO 3) 3
・ There are nH ₂ O, etc., and those that generate germanium oxide include Ge (OC ₂ H ₅ ) ₄ , Ge (OC ₄ H ₉ ) ₄ , GeCl
There are ₄ etc., and Al (O
_{C 2 H 5) 3, Al} (OC 3 H 7-i) 3, Al (OC 4 H 9)
₃ , In (AcAc) ₃ , In (NO 3) ₃ , nH ₂ O, etc.,
P (OC ₂ H ₅ ) ₃ , PO
_{(OCH 3) 3, PO (} OC 2 H 5) 3, H 3 PO 4, include P ₂ O _5, as producing boron oxide, B (OCH
₃ ) ₃ , B (OC ₂ H ₅ ) ₃ , B (OC ₄ H ₉ ) ₃ , B (AcAc)
₃ , BCl ₃ , H ₃ BO _3, etc., and these normally usable compounds or mixtures thereof can be used. In the chemical formula, AcAc represents CH ₃ COCHCOCH ₃ (acetylacetonate).

As a chemical agent for producing a titanium oxide thin film,
Ti (OC ₂ H ₅ ) ₄ , Ti (OC ₃ H _7-i ) ₄ , Ti (OC ₄ H ₉ )
₄ , titanium alkoxides such as Ti (OC ₄ H ₉ ) ₂ Cl ₂ , titanium alkoxides with glycols such as ethylene glycol, carboxylic acids such as acetic acid and lactic acid, alkanolamines such as triethanolamine, β-diketones such as acetylacetone. An addition reaction product or complex with a compound, and a chloride such as TiCl ₄ dissolved in a general-purpose alcohol such as ethanol, a solvent such as acetic acid ester or β-diketone, or a mixture thereof can be used.

Various additives can be added by known methods to accelerate the photocatalytic reaction. For example, a trace amount of metal (gold, platinum, palladium, silver, copper, zinc) is uniformly supported on a titanium oxide thin film by a photodeposition method utilizing a photocatalytic reaction to such an extent that light transmission is not lost, and the oil decomposition activity It is also possible to impart a high self-cleaning property due to the improvement or a high antibacterial activity.

Further, in order to impart an electromagnetic wave shielding function, an indium-doped tin oxide film is formed on the precoat layer to impart conductivity, and a titanium oxide thin film is further formed on the indium-doped tin oxide film to form an electromagnetic wave from the outside. Can be shielded by the window glass according to the present invention.

[0050]

As described in detail above, the window glass according to the present invention is a window glass in which a titanium oxide thin film having a photocatalytic action is provided on at least one surface of a glass plate. The linear transmittance for light having a wavelength of 550 nm is 50% or more, and the linear transmittance for light having a wavelength of 350 nm is 50% or less, and ultraviolet light containing at least light having a wavelength of 300 to 400 nm is 5 mW / cm ^2. When the thin film is irradiated with the above-mentioned intensity, it is capable of decomposing 0.5 μg or more of linoleic acid per 1 cm ² of the thin film. It also makes it possible to effectively break down even fat and oil components that are attached to the living space, and to obtain a revolutionary self-cleaning performance.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a window glass according to Reference Example 1 .

FIG. 2 Reference Examples 1 to 4, Examples 1 to 5 and Comparative Examples 1 to 3.
It is the figure which showed the characteristic of as a table.

FIG. 3 is a cross-sectional view of the window glass according to the second embodiment.

[Explanation of symbols]

1 ... Glass plate, 2 ... Titanium oxide thin film layer, 3 ... Precoat (SiO ₂ ) layer.

   ─────────────────────────────────────────────────── ─── Continued front page    (73) Patent holder 592116165               Kazuhito Hashimoto               2 2073 Iijima-cho, Sakae-ku, Yokohama-shi, Kanagawa                 NEW CITY Hongodai D Wing No.213 (73) Patent holder 594180092               Tomokazu Yoda               5-9-14-404 Minami Osawa, Hachioji City, Tokyo (72) Inventor Akira Fujishima               710-5 Nakamaruko, Nakahara-ku, Kawasaki City, Kanagawa Prefecture (72) Inventor Kazuhito Hashimoto               2703 Iijima-cho 2073, Sakae-ku, Yokohama-shi, Kanagawa               NEW CITY Hongodai D Wing No.213 (72) Inventor Tomokazu Yata               5-9 Minami Osawa, Hachioji City, Tokyo               Le Colline Minami Osawa Building No.14, No.404 (72) Inventor Shigemichi Miyama               3777-6 Tomitsukacho, Hamamatsu City, Shizuoka Prefecture                (56) Reference JP-A-7-51646 (JP, A)                 JP-A-6-278241 (JP, A)                 JP 9-920 (JP, A)                 International publication 96/13327 (WO, A1)                 International publication 96/29375 (WO, A1)

Claims (5)

(57) [Claims] 1. A window glass having a titanium oxide thin film having a photocatalytic action on at least one surface of a glass plate, wherein the titanium oxide thin film has a linear transmittance of 50% or more for light having a wavelength of 550 nm, The linear transmittance for light having a wavelength of 365 nm is 50% or less, and the film thickness is 0.02 between the glass plate and the titanium oxide thin film.
A glass for windows, which is provided with a pre-coated thin film having a thickness of 1 μm. 2. The titanium oxide thin film is at least
It contains a crystal of Tase and has a film thickness of 0.1 to 5
The window glass according to claim 1, wherein the window glass has a thickness of μm . Wherein the titanium oxide thin film, silver, copper, claim 1 or at least one additive selected from the group consisting of zinc, characterized in that it comprises 0.05 to 5 atomic% with respect to titanium atoms The glass for windows described in 2 . 4. The method of claim, wherein the precoat film is a thin film made of a material mainly composed of SiO ₂
The window glass according to any one of 1 to 3 . 5. The claims at least one layer of the precoat film is characterized to include a thin film made of a material mainly composed of indium oxide and / or tin oxide 1
The glass for windows according to any one of 1 to 4 .