Glass plate with antibacterial film, its producing method, and article having the glass plate

The present invention relates to a glass plate with an antibacterial film and a method for producing the same, and further relates to an article having the glass plate.

The need for a comfortable living space is extremely high, and in Japan in particular, the growth of bacteria, microorganisms, etc. becomes active in a hot and humid environment. Such bacteria, microorganisms, etc. often have an adverse effect on the human body, and in order to effectively inhibit their reproduction, plate-shaped antibacterial members that can be used as constituent members of living spaces and inexpensive mass production There is a need for a possible method for manufacturing the member.

For example, Patent Document 1 discloses an antibacterial processed plate glass material capable of forming a coating film with a resin composition containing titanium oxide or the like as an antibacterial agent and exerting an antibacterial effect. However, in the antibacterial processed plate glass material, roll coating, dip coating, spray coating, electrostatic coating, electrodeposition coating, wire coating, flow coating, doctor coating, etc. Since the coating film is formed by any of the methods selected from the above, the thickness of the coating film is in the micron unit of 10 to 50 μm, and it is not possible to uniformly form a film thinner than these. It was. In the present specification, a film formed on the surface of a member in order to impart antibacterial properties to the member is referred to as an "antibacterial film". As the antibacterial film, a metal material such as silver, zinc, or copper, or a photocatalytic material such as titanium oxide is used.

Titanium oxide is widely used as a photocatalytic material because it has high photocatalytic activity and excellent chemical stability. When titanium oxide is irradiated with ultraviolet rays, electrons and holes are generated, and a photo-induced decomposition reaction or a photo-induced hydrophilic reaction is exhibited. Antibacterial tiles and the like utilizing these reactions have already been commercialized.

Patent Document 2 discloses a technique of sintering powdered titanium oxide on a glass plate. Although a plate-shaped antibacterial member can be obtained by using this technique, when the particulate titanium oxide is coated on the glass plate, the titanium oxide particles aggregate and the particle size of titanium oxide is unavoidable. Becomes larger. As the particle size of titanium oxide increases, the film thickness of the antibacterial film containing titanium oxide increases. As a result, there is a problem that the reflectance of the antibacterial film becomes high and the interference color of the reflection becomes conspicuous.

Further, the method of Patent Document 2 has a problem that the mechanical durability of the antibacterial film is low because the antibacterial film is formed by using powdered titanium oxide. Further, it is difficult to uniformly form an antibacterial film on a large-area glass substrate, and it is necessary to perform a firing treatment or a coating treatment, and as a result of increasing the number of manufacturing processes, there is also a problem that the manufacturing cost increases. , It was not suitable for continuous mass production of large-area glass plates.

Further, the method for producing a nitrogen-doped titanium oxide film disclosed in Patent Document 3 is an invention relating to a method for producing a glass plate having an antibacterial film formed on the surface thereof, and is TiO by a sputtering method.₂This is a method in which a film is formed and then fired in an atmosphere containing ammonia and nitrogen. However, although the method of Patent Document 3 can obtain a plate-shaped antibacterial member, it requires a large-scale vacuum device and often requires a huge cost for the film forming device. In addition, there is a problem that it is necessary to perform a firing process, the number of manufacturing processes increases, and the manufacturing cost increases. As described above, the method for producing a nitrogen-doped titanium oxide film disclosed in Patent Document 3 is not suitable for continuous mass production of a large-area glass plate.

<patcit num="1"><text>Japanese Unexamined Patent Publication No. 2001-73438</text></patcit><patcit num="2"><text>International Publication No. 94/11092 Pamphlet</text></patcit><patcit num="3"><text>International Publication No. 01/10552 Pamphlet</text></patcit>

<p> The present invention has been completed by paying attention to the above-mentioned problems. An object of the present invention is to provide a glass plate with an antibacterial film provided with an antibacterial film in which reflection interference color is unlikely to occur. Another object of the present invention is to provide a method for manufacturing a glass plate having a large area on which an antibacterial film is formed and having enhanced mechanical durability of the antibacterial film in a large amount at low cost.</p>

<p>The glass plate with an antibacterial film of the present invention is a glass plate with an antibacterial film having an antibacterial film directly or via an undercoat film on the glass plate, and the film thickness of the antibacterial film is 2 nm or more and 100 nm or less.</p><p> In a preferred embodiment, the antibacterial performance of the antibacterial film is 10 μW / cm based on the light irradiation film adhesion method established by the Antibacterial Product Technology Council.²It is an antibacterial performance that reduces the number of Staphylococcus aureus or Escherichia coli after being irradiated with ultraviolet light of the amount of light for 24 hours to 1/100 or less of the number of bacteria before light irradiation.</p><p> In a preferred embodiment, the antibacterial performance of the antibacterial film is 10 μW / cm based on the light irradiation film adhesion method established by the Antibacterial Product Technology Council.²It is an antibacterial performance that reduces the number of Staphylococcus aureus or Escherichia coli after irradiation with ultraviolet light of the amount of light for 8 hours to 1/100 or less of the number of bacteria before light irradiation.</p><p> In a preferred embodiment, the antibacterial performance of the antibacterial film is the number of yellow staphylococcus or Escherichia coli after irradiation with a white fluorescent lamp having a light amount of 1000 Lx for 24 hours based on the light irradiation film adhesion method defined by the Antibacterial Product Technology Council. Is an antibacterial performance that reduces the number of bacteria to 1/100 or less of the number of bacteria before light irradiation.</p><p>In a preferred embodiment, the antibacterial performance of the antibacterial film is the number of yellow staphylococcus or Escherichia coli after irradiation with a white fluorescent lamp having a light amount of 500 Lx for 24 hours based on the light irradiation film adhesion method defined by the Antibacterial Product Technology Council. Is an antibacterial performance that reduces the number of bacteria to 1/100 or less of the number of bacteria before light irradiation.</p><p> In a preferred embodiment, the antibacterial performance of the antibacterial film is the number of yellow staphylococcus or Escherichia coli after irradiation with a white fluorescent lamp having a light amount of 250 Lx for 24 hours based on the light irradiation film adhesion method defined by the Antibacterial Product Technology Council. Is an antibacterial performance that reduces the number of bacteria to 1/100 or less of the number of bacteria before light irradiation. </p><p> In a preferred embodiment, the antibacterial performance is an antibacterial performance that reduces the number of Staphylococcus aureus or Escherichia coli to 1/10000 or less.</p><p> In a preferred embodiment, the film thickness of the antibacterial film is 5 nm or more and 80 nm or less, and in a more preferable embodiment, the film thickness of the antibacterial film is more than 25 nm and less than 70 nm.</p><p> In a preferred embodiment, the main component of the antibacterial film is one selected from the group consisting of titanium oxide, nitrogen-doped titanium oxide, titanium oxynitride and titanium nitride.</p><p> In a preferred embodiment, the main component of the antibacterial membrane is nitrogen-doped titanium oxide.</p><p> According to another aspect of the present invention, there is provided a method for producing a glass plate with an antibacterial film. In this production method, the antibacterial film is formed by a thermal decomposition method.</p><p> In a preferred embodiment, the antibacterial film is formed by supplying a film-forming gas to the surface of the glass plate held above the temperature at which the film-forming gas decomposes or the surface of the glass ribbon in the glass plate manufacturing process.</p><p> In a preferred embodiment, the film-forming gas comprises a titanium-containing compound, a nitrogen-containing compound and an oxidizing gas.</p><p> In a preferred embodiment, the film-forming gas further comprises a reaction inhibitor that suppresses a chemical reaction between the titanium-containing compound and the nitrogen-containing compound.</p><p> In a preferred embodiment, the nitrogen-containing compound is ammonia.</p><p> In a preferred embodiment, the oxidizing gas is oxygen.</p><p> In a preferred embodiment, the molar ratio of oxygen to ammonia in the coating gas is 0.05 or more.</p><p> In a preferred embodiment, the reaction inhibitor is hydrogen chloride.</p><p> In a preferred embodiment, the thermal decomposition method is a CVD method performed in a bath for forming a molten glass ribbon into a plate shape in a glass manufacturing process by a float method.</p><p> According to yet another aspect of the present invention, a glass window of a building is provided. They have the glass plate with the antibacterial film. For example, glass windows in living spaces or medical facilities, indoor glass, etc. are provided.</p><p> According to yet another aspect of the invention, glass partitions within a building are provided. They have the glass plate with the antibacterial film.</p><p> According to yet another aspect of the invention, furniture is provided. They have the glass plate with the antibacterial film. For example, glass tables, glass shelves, glass showcases or glass food cases are provided.</p><p> According to yet another aspect of the present invention, a glass window of a transport machine is provided. They have the glass plate with the antibacterial film. For example, glass windows for vehicles, ships or aircraft are provided.</p><p> According to yet another aspect of the present invention, a glass panel for displaying information is provided. They have the glass plate with the antibacterial film. For example, a display panel, a touch panel, and the like are provided.</p>

<p> According to the present invention, since the thickness of the antibacterial film is set in the range of 2 nm or more and 100 nm or less, the antibacterial film in which the generation of reflection interference color is suppressed even when a titanium compound having a relatively high refractive index is used. A glass plate with an antibacterial film is provided.</p><p> Further, according to the present invention, in the process of manufacturing float glass, a large area is obtained by performing a thermal decomposition method in a bath for forming a molten glass ribbon into a plate shape, and the mechanical durability of the antibacterial film is large. A method for inexpensively producing a large amount of glass plates with an antibacterial film having improved properties is provided.</p><p> Further, according to the present invention, an article having a glass with an antibacterial film is provided.</p>

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments.

As used herein, the term "antibacterial" means suppressing the growth of bacteria or microorganisms adhering to an object and reducing the viable count of bacteria or microorganisms over time. The term "principal component" means a component that accounts for 50% by weight or more. The term "light irradiation film adhesion method specified by the Antibacterial Product Technology Council" means the light irradiation film adhesion method (2003 version) specified by the Antibacterial Product Technology Council, and unless otherwise noted, the adhesion is concerned. Evaluate antibacterial performance based on the conditions stipulated by law.

FIG. 1 is a schematic cross-sectional view illustrating two forms of the glass plate 4 with an antibacterial film according to the present invention. In the glass plate according to the present invention, as the first form, the antibacterial film 2 is formed on the glass plate 1 as shown in FIG. 1 (a).

Further, as the second form, as shown in FIG. 1 (b), it is preferable to sandwich one or more layers of the base film 3 between the glass plate 1 and the antibacterial film 2. It is preferable that this base film has a role such as an alkali barrier function. When the glass plate 1 is a glass plate containing an alkaline component, for example, if the alkaline component moves to the antibacterial film 2 during the film forming process of the antibacterial film 2, the crystallinity of the antibacterial film deteriorates and the antibacterial performance deteriorates. In that case, if the base film is configured to sandwich the base film, it is possible to prevent an adverse effect due to the movement of the alkaline component.

[Preferable range of film thickness]

(Antibacterial film) If the film thickness of the antibacterial film is large, it shows reflection interference color and significantly deteriorates the appearance quality. On the other hand, if the film thickness is too small, the reflection interference color is suppressed, but the antibacterial performance is deteriorated. Therefore, the film thickness of the antibacterial film is preferably in the range of 2 nm or more and 100 nm or less, and more preferably in the range of 5 nm or more and 80 nm or less. Further, the range of more than 20 nm and less than 70 nm is most preferable.

[Antibacterial performance]

The antibacterial performance of the antibacterial film of the present invention is 10 μW / cm in the light irradiation film adhesion method (2003 version) established by the Antibacterial Product Technology Council.²The antibacterial performance that reduces the number of Staphylococcus aureus or Escherichia coli after being irradiated with ultraviolet light of the same amount of light for 24 hours to 1/100 or less of the number of bacteria before light irradiation is preferable. More preferably, 10 μW / cm²It is an antibacterial performance that reduces the number of Staphylococcus aureus or Escherichia coli after irradiation with ultraviolet light of the amount of light for 8 hours to 1/100 or less of the number of bacteria before light irradiation. In addition, in the light irradiation film adhesion method (2003 version) established by the Antibacterial Product Technology Council, the number of Staphylococcus aureus or Escherichia coli after irradiation with a white fluorescent lamp with a light intensity of 1000 Lx for 24 hours is calculated as the number of bacteria before light irradiation. Antibacterial performance that reduces the number to 1/100 or less is preferable. More preferably, it is an antibacterial performance that reduces the number of Staphylococcus aureus or Escherichia coli after irradiation with a white fluorescent lamp having a light amount of 500 Lx for 24 hours to 1/100 or less of the number of bacteria before light irradiation. More preferably, it is an antibacterial performance that reduces the number of Staphylococcus aureus or Escherichia coli after irradiation with a white fluorescent lamp having a light amount of 250 Lx for 24 hours to 1/100 or less of the number of bacteria before light irradiation. Since the antibacterial performance evaluation is a test using microorganisms, the evaluation test error is larger than that of other physical property evaluations. If the number of bacteria after light irradiation is 1/100 or less (sterilization rate of 99% or more), it can be said that there is clearly an advantageous effect on antibacterial performance, not within the error range. The Japan Building Materials and Housing Equipment Industry Association also shows the difference between antibacterial processed products and unprocessed products if the bacterial survival rate is 1% or less (the number of bacteria is reduced to 1/100 or less) in the antibacterial performance evaluation. Is said to be able to be significantly determined. In a more preferable range, the number of bacteria after light irradiation is 1/1000 or less. In a more preferable range, the number of bacteria after light irradiation is 1/10000 or less.

In the antibacterial performance evaluation, it is necessary to set the intensity of the ultraviolet light to be irradiated and the illuminance of the white fluorescent lamp according to the usage situation. The intensity of ultraviolet light and the illuminance of white fluorescent lamps are typified by the following places of use. Ultraviolet light 10 μW / cm² A place in the room in the daytime, about 1.5m away from the window where sunlight enters. Fluorescent lamp 1000Lx A place at a height of about 1m from the floor in the room where only the fluorescent lamp is lit. The intensity of ultraviolet light in a fluorescent lamp 1000Lx is 4μW / cm.²degree. Fluorescent lamp 500Lx The floor surface of the room where only the fluorescent lamp is lit. The intensity of ultraviolet light in a fluorescent lamp 1000Lx is 2μW / cm.²degree.

The bacteria to be reduced by the present invention are not particularly limited, but the present invention can be used for the following fungi. For example, there are gram-positive bacteria (Staphylococcus aureus, Bacillus, etc.) or gram-negative bacteria (Escherichia coli, Salmonella, etc.), fungi such as molds, mushrooms, yeasts, other viruses, and protozoa.

[Ingredients of antibacterial membrane]

The main component of the antibacterial film of the present invention is preferably one selected from the group consisting of titanium oxide, nitrogen-doped titanium oxide, titanium oxynitride and titanium nitride. This is because an antibacterial film containing these as a main component has high antibacterial performance and excellent chemical stability.

In particular, it is preferable that the main component is nitrogen-doped titanium oxide. In particular, nitrogen-doped titanium oxide is a photocatalytic material that responds to light in the visible light region, and is therefore preferable in that light in the visible light region, which is abundant in sunlight and fluorescent lamps, can be used.

[material]

(Raw Material of Antibacterial Membrane) The raw material of the antibacterial membrane of the present invention needs to contain at least one kind of titanium-containing compound, at least one kind of nitrogen-containing compound, and at least one kind of oxidizing gas. Is.

As the titanium-containing compound, titanium chloride, titanium alkoxide, titanium chelate compound and the like are preferable. These titanium-containing compounds are preferably gas or liquid at room temperature, and when they are liquid at room temperature, they preferably have a low boiling point. These preferable titanium-containing compounds can be vaporized as they are or by heating a little, and can be used as a component of the raw material gas. Further, a titanium-containing compound that sublimates even if it is solid at room temperature, or a titanium-containing compound that can be dissolved in an organic solvent such as alcohol or toluene can also be used.

Examples of such titanium-containing compounds include titanium tetrachloride (TiCl).₄), Titanium ethoxydo (Ti (OC)₂H₅)₄), Titanium Isoproxide (Ti (OC)₃H₇)₄), Titanium Normal Butoxide (Ti (OC)₄H₉)₄), Titanium Acetylacetone ((C)₃H₇O₂)₂Ti (C₅H₇O₂)₂) Etc. can be exemplified. In particular, titanium tetrachloride (TiCl)₄), Titanium Isoproxide (Ti (OC)₃H₇)₄), Or Titanium Normal Butoxide (Ti (OC)₄H₉)₄), Is preferably used.

Ammonia (NH) is a nitrogen-containing compound.₃), Amines and hydrazine derivatives can be exemplified as suitable. Among these, ammonia is preferable because it is easily liquefied by compression and is a gas at normal temperature and pressure, so that it can be easily introduced into a raw material gas, and it is particularly preferable because it can be obtained in large quantities at low cost. Since amines and hydrazine derivatives are highly reactive, they are excellent in that high-quality films can be easily produced. On the other hand, the disadvantage is that it is expensive.

As an oxidizing gas, oxygen (O)₂) Is preferred, and carbon dioxide (CO)₂), Carbon monoxide (CO), water vapor (H)₂Oxygen-containing compounds such as O) can be used. Water (H₂When a liquid raw material such as O) or ester is used, equipment for vaporizing the liquid raw material is required, and the amount of vaporization tends to be unstable. It is preferable to use a gas raw material whose supply amount can be easily controlled. Of these, it is particularly preferable to use oxygen. Also, air can be used. When air is used as an oxidizing gas, nitrogen (N) contained in the air₂) Can act as a reaction diluent.

When ammonia is used as the nitrogen-containing compound and oxygen is used as the oxidizing gas, the molar ratio of oxygen to ammonia (O)₂/ NH₃The ratio) is preferably 0.05 or more. This is because the crystallinity of the film can be improved by setting the molar ratio of oxygen to ammonia to 0.05 or more. The recombination of the generated electrons and holes is thought to occur at the defect site of the crystal. Therefore, by improving the crystallinity, that is, reducing the defect sites of the crystal, the rate of recombination of electrons and success can be reduced and the antibacterial property can be enhanced.

The raw material of the antibacterial membrane of the present invention preferably further contains a reaction inhibitor that suppresses a chemical reaction between the titanium-containing compound and the nitrogen-containing compound.

It is preferable to use hydrogen chloride as the reaction inhibitor .

When titanium tetrachloride is used as the titanium-containing compound and ammonia is used as the nitrogen-containing compound, the vapor phase reaction may proceed before the raw material gas reaches the glass plate. As this gas phase reaction proceeds, a solid reaction product is produced in the raw material gas pipe. This reaction product can clog the pipe. Further, this reaction product is transported to the surface of the glass plate by the flow of the raw material gas and is taken into the film to be formed, which causes defects such as pinholes. In order to prevent this gas phase reaction, it is preferable to use hydrogen chloride as a reaction suppressor.

[Manufacturing method of glass plate with antibacterial film]

The method for producing the above-mentioned antibacterial film is not particularly limited, and in addition to a known thermal decomposition method such as a thermal CVD method or a spray method, a fine powder of the above-mentioned antibacterial film is adhered to the glass surface, and then the glass is used together. An example is a method of heating to agglomerate the fine powder. Further, after the fine powder is agglomerated, the antibacterial film may be crystal-grown with the agglomerated fine powder as a nucleus by a thermal decomposition method. Among these, according to the thermal decomposition method, particularly the thermal CVD method, a film having high mechanical durability can be easily formed.

The film formation by the thermal CVD method can be performed, for example, by using a glass plate as a substrate, heating a glass plate having a predetermined size, and spraying a gaseous raw material on the surface of the heated glass plate.

Specifically, it can be carried out as follows. The glass plate is placed on a mesh belt and transported, and passed through a tunnel-shaped heating furnace. The glass plate is transported into a heating furnace and heated to a temperature at which the film-forming gas decomposes (hereinafter, abbreviated as "film-forming gas decomposition temperature"). When the glass plate is heated to the film forming gas decomposition temperature, the raw material gas is supplied into the heating furnace. The raw material gas reacts with the heat of the surface of the glass plate, and an antibacterial film having an antibacterial action is formed on the glass plate.

The film-forming gas decomposition temperature is preferably 500 ° C. or higher from the viewpoint that high crystallinity can be obtained and a high film-forming rate can be obtained. That is, it is preferable to form an antibacterial film on the surface of a glass plate at 500 ° C. or higher. If it is less than 500 ° C, TiNCl, TiCl₄ This is because low-temperature products such as nNH3 are likely to be formed.

Further, in the thermal CVD method, the high temperature of the glass plate is utilized in the step of forming the glass melt into the glass plate or the slow cooling step after the glass plate is formed in the glass plate manufacturing process. Is preferable. This is because if the raw material gas is supplied onto a high-temperature glass plate, a thin film can be formed without using a separate heating facility. Further, in this way, a thin film can be formed on a glass plate having a large area at high speed, and a glass plate with a thin film for applications requiring a large area such as a building, a vehicle, and a display panel can be manufactured. As described above, the method of forming a film on a high-temperature glass plate during the manufacturing process is called an online CVD method.

(In-bus CVD method) The above-mentioned step of forming a glass plate from a glass melt is performed in a molten tin tank (called a float bath) in a glass plate manufacturing process by a float method. The glass melt melted in the melting furnace (called a float kiln) flows into the float bath. The glass melt is stretched onto a long strip of plate without interruption and is called a glass ribbon.

The method of performing the online CVD method in the float bus is called the in-bus CVD method. In addition to the advantages described above, the in-bus CVD method has the following advantages. First, the atmosphere inside the float bath is controlled so that the atmosphere does not enter. Therefore, it is possible to suppress defects such as pinholes. Moreover, the temperature of the glass ribbon in the float bath is very high. The temperature depends on the composition of the glass ribbon, but in the case of ordinary soda lime silicate glass, it is in the range of 650 to 1150 ° C, for example.

Within such a temperature range, the crystallinity of the thin film having antibacterial performance can be improved and the antibacterial performance can be enhanced. Further, since the raw material gas exhibits sufficient reactivity, a thin film having a sufficient thickness and antibacterial activity can be easily formed on the glass ribbon without slowing down the transport speed of the glass ribbon. As a result, the productivity can be expected to be improved, so that a large amount of glass plates with an antibacterial film can be manufactured at low cost.

FIG. 2 shows a form of an apparatus for forming a film on a glass ribbon by the in-bus CVD method in the float method. As shown in FIG. 2, in this device, a predetermined number of coaters 16 float at a predetermined distance from the surface of the glass ribbon 10 that flows out from the float kiln 11 into the float bath 12 and moves in a band shape on the molten tin 15. It is located in the bus. Although three coaters 16a, 16b, and 16c are shown in FIG. 2, the number of coaters can be appropriately designed by designing the film configuration and the like. From these coaters, raw materials for an antibacterial film and an undercoat film having an antibacterial action are supplied in a gas state, and each thin film is continuously formed on the glass ribbon 10. Further, if a plurality of coaters are used, a thin film can be laminated on the glass ribbon 10. The temperature of the glass ribbon is adjusted by a heater and a cooler (not shown) arranged in the float bath so as to reach a predetermined temperature immediately before the coater 16. The glass ribbon 10 on which the thin film is formed is pulled up by the roller 17 and sent to the rare (slow cooling kiln) 13. The glass plate slowly cooled by the rare 13 is cut into a glass plate having a predetermined size by a general-purpose cutting device (not shown).

(Intra-rare CVD method) As described above, the online CVD method can also be performed in a slow cooling step (called rare) after being formed into a glass plate. In this case, the introduction of the source gas is carried out at the entrance of the rare (slow cooling kiln) and / or inside the rare. Hereinafter, this method is referred to as an intra-rare CVD method. The glass ribbon near the rare entrance or the rare entrance in the rare has a low temperature as compared with the inside of the bath, but has a sufficiently high temperature for the film formation reaction. Unlike the in-bus CVD method, the in-rare CVD method has the following features. First, even raw materials that are not suitable for the in-bath CVD method, for example, raw materials whose reaction rate is too fast at the glass ribbon temperature of the in-bath CVD method, or raw materials that may have an unfavorable effect on the float bath. , Can be adopted. Further, it can be applied to a glass plate manufacturing process that does not have a float bath. For example, it can be applied to the glass plate manufacturing process by the roll-out method to manufacture a template glass, a meshed glass, and a wire-reinforced glass having an antibacterial film having an antibacterial effect.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples. (Examples 1 to 12, Comparative Example) A 0.7 mm-thick non-alkali glass plate was cut into a square with a side of 10 cm, washed, and then dried. A nitrogen-doped titanium oxide film was formed on one surface of this glass plate by a normal pressure thermal CVD method using a transfer furnace of a normal pressure thermal CVD apparatus. Specifically, it is as follows.

The above-mentioned glass plate was placed on a mesh belt and conveyed in the above-mentioned furnace to heat the glass plate. A nitrogen-doped titanium oxide film was formed by supplying a raw material gas to the surface of the glass plate in a region inside the furnace where the temperature of the glass plate reached about 850 ° C. Titanium tetrachloride (TiCl) is used as this raw material gas.₄), Oxygen (O₂), Ammonia (NH₃), Hydrogen chloride (HCL) was adopted as the reaction inhibitor, and a gas diluted to a predetermined concentration with nitrogen gas was used. A nitrogen-doped titanium oxide film was formed by adjusting the concentration and transport rate of the raw material gas.

(Examples 12 to 13) Using the apparatus shown in FIG. 2, a thin film was formed on the surface of the glass ribbon by the in-bus CVD method. Specifically, it is as follows.

A glass melt melted in a float kiln and whose temperature was controlled to 1150 to 1100 ° C. was flowed into a float bath. In the float bath, the glass melt was formed into a glass ribbon while being cooled. The glass ribbon was molded to a thickness of 4.0 mm. SiO as a base film on the glass ribbon by the first coater (16a in Fig. 2)₂The film was formed to have a thickness of 50 nm. Then, the raw material gas was sprayed from the second coater (16b in FIG. 2) to form a thin film.

In Example 13, the raw material gas is titanium tetrachloride (TiCl).₄), Ethyl acetate (C₄H₈O₂) Was adopted, and a gas diluted to a predetermined concentration with nitrogen gas was used. A titanium oxide film was formed by adjusting the concentration of the raw material gas and the transport speed.

In Example 14, a nitrogen-doped titanium oxide film was formed using the same raw material gas as in Examples 1 to 12 and Comparative Example.

(Thickness of antibacterial film) The cross section of the glass plate on which the thin film was formed was measured by observing with a scanning electron microscope (SEM).

(Interference color) The presence or absence of interference color was judged by visual observation.

(Antibacterial performance) The antibacterial properties of the obtained film were evaluated by the light irradiation film adhesion method established by the Antibacterial Product Technology Council.

(Antibacterial performance test 1) Based on the light irradiation film adhesion method specified by the Antibacterial Product Technology Council, a black light fluorescent lamp (FL20S / BLB / JET20W manufactured by Toshiba Lighting &amp; Technology) is used, and an ultraviolet intensity meter (UVR-2 manufactured by Topcon) is used. The ultraviolet intensity measured by the light receiving part UD-36) is 10 μW / cm.²The cells were irradiated with ultraviolet rays for 24 hours under the conditions of humidity of 95% and temperature of 25 ° C. Evaluation was performed using Staphylococcus aureus NBRC12732 as the test bacterium. In addition, for Examples 3, 5, 8 to 14, evaluation using Escherichia coli (Escherichiacoli NBRC3972) as a test bacterium was also carried out. In both the thin films of Examples 1 to 14 and Comparative Examples, the number of Staphylococcus aureus after 24 hours of ultraviolet irradiation was reduced to 1/100 or less, and they had good antibacterial properties. Further, in the thin films of Examples 3, 5, 8 to 14, the number of Escherichia coli after 24 hours of ultraviolet irradiation was reduced to 1/100 or less, and had good antibacterial properties.

(Antibacterial performance test 2) For Examples 3, 5, 8 to 14, the ultraviolet intensity was 10 μW / cm.²The test was carried out in the same manner as in (Antibacterial Performance Test 1) above, except that the irradiation time of ultraviolet rays was set to 8 hours. Evaluation was performed using Staphylococcus aureus NBRC12732 as the test bacterium. In all of the thin films of Examples 3, 5, 8 to 14, the number of bacteria after 24 hours of ultraviolet irradiation was reduced to 1/100 or less, and had good antibacterial properties.

(Antibacterial performance test 3) For Examples 3, 5, 8 to 14, based on the above-mentioned light irradiation film adhesion method established by the Antibacterial Product Technology Council, a white fluorescent lamp was used and the illuminance was adjusted to 1000 Lx. The test was carried out in the same manner as in the above (antibacterial performance test 1) except that the irradiation time of the white fluorescent lamp was set to 24 hours. Evaluation was performed using Staphylococcus aureus NBRC12732 and Escherichia coli NBRC3972 as test bacteria. In all of the thin films of Examples 3, 5, 8 to 14, the number of bacteria after 24 hours of ultraviolet irradiation was reduced to 1/100 or less, and had good antibacterial properties.

(Antibacterial performance test 4) For Examples 3, 5, 9 to 14, based on the above-mentioned light irradiation film adhesion method established by the Antibacterial Product Technology Council, a white fluorescent lamp was used and the illuminance was adjusted to 500 Lx. The test was carried out in the same manner as in the above (antibacterial performance test 1) except that the irradiation time of the white fluorescent lamp was set to 24 hours. Evaluation was performed using Staphylococcus aureus NBRC12732 as the test bacterium. In all of the thin films of Examples 3, 5, 9 to 14, the number of bacteria after 24 hours of ultraviolet irradiation was reduced to 1/100 or less, and had good antibacterial properties.

(Antibacterial performance test 5) For Examples 4, 9, 12 to 13, based on the above-mentioned light irradiation film adhesion method established by the Antibacterial Product Technology Council, a white fluorescent lamp was used and the illuminance was adjusted to 250 Lx. The test was carried out in the same manner as in the above (antibacterial performance test 1) except that the irradiation time of the white fluorescent lamp was set to 24 hours. Evaluation was performed using Staphylococcus aureus NBRC12732 as the test bacterium. In all of the thin films of Examples 4, 9, 12 to 13, the number of bacteria after 24 hours of ultraviolet irradiation was reduced to 1/100 or less, and had good antibacterial properties.

The above results are shown in the table.

<tables num="1"><img file="JP2007254192A_D0001.tif" /></tables>

As shown in the table, the thin films of Examples 1 to 14 had a film thickness in the range of 5 to 80 nm, so that no interference color was generated. On the other hand, the thin film of the comparative example having a film thickness of 150 nm had an interference color.

The glass plate with an antibacterial film of the present invention is different from the conventional one in the fields of glass windows of buildings, glass windows of transportation machines, glass panels for information display, etc. It has great utility value in that it can provide a glass plate with an enhanced antibacterial film.

<figref num="1">1 Glass plate 2 Antibacterial film 3 Base film 4 Glass plate with antibacterial film</figref><figref num="2">It is a schematic diagram of the apparatus used for the online CVD method.</figref>

Code description

10 Glass Ribbon 11 Melting Furnace 12 Float Bath 13 Slow Cooling Furnace 16 Coater 17 Roller