JPH10199311A - Lighting system for tunnel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain water repellency for a long period and control a spread of contamination for a cover surface by forming virtually a transparent surface layer that contains photo catalyst particles, water repellent silicone and a substance to prevent water repellent silicone from having a hydrophilic property by means of the light excitation of the photo catalyst. SOLUTION: A lighting system 10 for a tunnel as a recessed type has a housing to be buried in the concrete wall of the tunnel. A light source 16 covered with a cover glass 18 is applicable to a high pressure sodium vapor lamp, low pressure sodium vapor lamp, metal halide lamp, fluorescent lamp, mercury vapor lamp, etc. The surface layer that contains photo catalyst particles, silicone, and cobalt or cobalt compound or the like which is the substance to prevent the silicone from having a hydrophilic property by the photo excitation of the photo catalyst is formed on the external surface of the cover glass 18. The layer that has the photo catalyst particles and water repellent silicone is formed on the surface of the cover glass 18 and the substance to prevent the silicone from having the hydrophile property is fixed in at least a part of the surface layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting device for a tunnel which is hardly contaminated with smoke or the like.

[0002]

2. Description of the Related Art The cover of a tunnel lighting device is contaminated by combustion products in exhaust gas and dust soaring from a road surface. With dirt, the light output of the lighting device decreases. Therefore, the cover must be cleaned regularly or as needed.

[0003]

The cleaning of tunnel lighting devices often requires traffic regulation and hinders smooth road traffic. Especially in tunnels, it is not only difficult to regulate traffic for cleaning lighting equipment,
Due to the considerable danger, it is not possible to carry out a thorough cleaning. In addition, since cleaning is a high-altitude operation and requires a long time, the time for traffic regulation tends to be long. Therefore, there is a demand for a tunnel lighting device that is less likely to be soiled.

[0004] As a method of preventing the adhesion of the dirt,
It is known that it is better to impart water repellency to the surface of a substrate. When water repellency is imparted to the surface of the base material, the surface energy is significantly reduced, so that it becomes difficult for dirt components to adhere. As one of the methods, there is a method of forming a surface layer made of a water-repellent silicone on a substrate surface. However, with this structure, the contact angle with water is reduced to about 70 ° due to the adhesion of dirt over time, and the effect of water repellency is not maintained. Therefore, as another method for solving the above-mentioned problem, there is a method of forming a surface layer comprising a photocatalyst and a water-repellent silicone on the surface of a substrate. According to this method, it is possible to decompose the adhered dirt over time based on the oxidative decomposability of the photocatalyst. However, in this configuration, when exposed to sunlight outdoors, the silicone is hydrophilized by photoexcitation of the photocatalyst, so that the water repellency of the surface cannot be maintained. In view of the above circumstances, it is an object of the present invention to provide a tunnel lighting device cover that can maintain the water repellency of the surface for a long period of time, and to provide a tunnel lighting device that is less likely to be soiled.

[0005]

According to the present invention, in order to solve the above-mentioned problems, photocatalyst particles, water-repellent silicone, and hydrophilicity of the water-repellent silicone by photoexcitation of the photocatalyst are provided on a cover surface. A substance for preventing the formation of a substantially transparent surface layer containing, or on the surface of the substrate,
A substantially transparent layer containing photocatalyst particles and water-repellent silicone is formed, and at least a part of the surface of the layer is used to prevent the water-repellent silicone from becoming hydrophilic by photoexcitation of the photocatalyst. A lighting device for a tunnel, characterized in that the substance is fixed. Preventing the silicon from becoming hydrophilic by photoexcitation of the photocatalyst by making the surface layer contain a substance such as cobalt or a cobalt compound for preventing the photocatalyst from becoming hydrophilic by photoexcitation. Can be. And because it contains a photocatalyst, based on the oxidative decomposability of the photocatalyst,
Dirt that adheres over time can be broken down. Therefore, the water repellency of the surface can be maintained, and the cover of the tunnel lighting device can be maintained in a state that is hardly stained permanently.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION A lighting device for a tunnel can be of an embedded type or a direct mounting type depending on the tunnel structure.
In the example shown in FIG. 1, the lighting device 10 is of a recessed type and has a housing 14 buried in a concrete wall 12 of the tunnel. The light source 16 is covered by a cover glass 18. The light source 16 includes a high-pressure sodium lamp, a low-pressure sodium lamp, a metal halide lamp,
Fluorescent lamps, mercury lamps, fluorescent mercury lamps and other electric lights can be used. As shown in FIG. 2, on the outer surface of the cover glass 18, a surface layer containing photocatalyst particles, silicon, and a substance for preventing photocatalytic excitation of photocatalyst such as cobalt or a cobalt compound by photoexcitation is formed. Have been. In another embodiment of the present invention, as shown in FIG. 3, a layer containing photocatalyst particles and a water-repellent silicone is formed on the surface of the cover glass 18, and at least a part of the surface of the layer is formed. Is a water-repellent silicone such as cobalt or a cobalt compound.
A substance for preventing the photocatalyst from becoming hydrophilic by photoexcitation is fixed.

A photocatalyst has an energy greater than the energy gap between the conduction band and the valence band of the crystal.
A substance capable of generating conduction electrons and holes by excitation of electrons in the valence band (photoexcitation) when irradiated with light (excitation light) having a short wavelength (excitation light).
Oxides such as zeta-type titanium oxide, zinc oxide, tin oxide, ferric oxide, bismuth trioxide, tungsten trioxide and strontium titanate can be suitably used. As a light source used for photoexcitation of the photocatalyst, illumination 16 in a tunnel such as a high-pressure sodium lamp, a low-pressure sodium lamp, a metal halide lamp, a fluorescent lamp, a mercury lamp, a fluorescent mercury lamp, and a lighting of a passing car such as a headlamp can be used.

The silicone has an average composition formula R _p SiO _{(4-p) / 2} (where R is a functional group comprising one or more monovalent organic groups, or a monovalent organic group) A resin represented by the following formula: X is an alkoxy group or a halogen atom, and p is a number satisfying 0 <p <2. Is available.

As the cobalt compound, cobalt alloy, cobalt oxide, cobalt chloride, cobalt sulfate, cobalt iodide, cobalt bromide, cobalt acetate, cobalt chlorate, cobalt nitrate and the like can be suitably used.

The thickness of the surface layer is preferably set to 0.4 μm or less. Then, cloudiness due to irregular reflection of light can be prevented, and the surface layer becomes substantially transparent. Further, it is more preferable that the thickness of the surface layer be 0.2 μm or less. Then, it is possible to prevent the surface layer from being colored by light interference. Also, the thinner the surface layer, the better its transparency. Further, when the film thickness is reduced, the wear resistance of the surface layer is improved.

A metal such as Ag, Cu and Zn can be added to the surface layer. The surface layer to which the metal is added can kill bacteria and fungi attached to the surface even in a dark place.

Pt, Pd, Ru, Rh, I
A platinum group metal such as r or Os can be added.
The surface layer to which the metal is added can enhance the redox activity of the photocatalyst, and can improve the decomposability of organic contaminants and the decomposability of harmful gases and odors.

Next, a surface layer containing photocatalyst particles, water-repellent silicone, and a substance for preventing the water-repellent silicone from becoming hydrophilic by photoexcitation of the photocatalyst is formed on the surface of the substrate. The method of manufacturing the water-repellent member described above will be described. The production method in this case is basically based on applying a coating composition on the surface of a substrate and curing the coating composition.

Here, the coating composition contains a precursor of silicon as an essential component of a substance for preventing photocatalytic particles, cobalt or a cobalt compound or the like from becoming hydrophilic by photoexcitation of a photocatalyst. Solvents such as ethanol and propanol, catalysts that promote hydrolysis of silicone precursors such as hydrochloric acid, nitric acid, sulfuric acid, acetic acid and maleic acid, and basic compounds such as tributylamine and hexylamine Silicon compounds such as acidic compounds such as aluminum, aluminum triisopropoxide and tetraisopropyl titanate;
And a surfactant for improving the dispersibility of the coating liquid such as a silane coupling agent.

As cobalt or a cobalt compound, a water-soluble cobalt compound is preferably used. As the water-soluble cobalt compound, for example, cobalt chloride, cobalt sulfate, cobalt iodide, cobalt bromide, cobalt acetate, cobalt chlorate, cobalt nitrate and the like can be suitably used.

[0016] Here silicone - The precursor emissions in the average composition formula _{R p SiX q O (4-} pq) / 2 ( wherein, R consists of one or more organic groups monovalent functional X or a functional group comprising two or more selected from a monovalent organic group and a hydrogen group, X is an alkoxy group or a halogen atom, and p and q are 0 <p <2, 0 <
a film-forming element composed of a siloxane represented by the following formula: q <4) or a general formula R _p SiX _4-p (where R is one or more monovalent organic groups) Wherein X is an alkoxy group or a halogen atom, and p is 1 or 2. A film-forming element comprising a hydrolyzable silane derivative to be
Can be suitably used.

Here, as the coating film forming element comprising the hydrolyzable silane derivative, methyltrimethoxysilane,
Methyltriethoxysilane, methyltripropoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, ethyltributoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, Phenyltributoxysilane,
Dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldipropoxysilane, dimethyldibutoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diethyldipropoxysilane, diethyldibutoxysilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, phenyl Methyldipropoxysilane, phenylmethyldibutoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltripropoxysilane, n-propyltributoxysilane, γ-glycoxydoxypropyltrimethoxysilane, γ -Acryloxypropyltrimethoxysilane and the like can be suitably used.

The film-forming element composed of the siloxane includes partial hydrolysis and dehydration-condensation polymerization of the hydrolyzable silane derivative, or partial hydrolyzate of the hydrolyzable silane derivative, tetramethoxysilane, tetramethoxysilane, It can be produced by dehydration polycondensation with a partial hydrolyzate such as ethoxysilane, tetrapropoxysilane, tetrabutoxysilane, diethoxydimethoxysilane and the like.

The coating method of the coating composition includes spray coating, dip coating, flow coating, spin coating, roll coating, brush coating, and sponge. A method such as coating can be suitably used. As a curing method, it can be carried out by polymerizing by heat treatment, standing at room temperature, ultraviolet irradiation, or the like.

Next, a layer containing photocatalyst particles and a water-repellent silicone is formed on the surface of the base material, and at least a part of the surface of the layer is formed by photoexcitation of the photocatalyst by the water-repellent silicone. A method for manufacturing a water-repellent member to which a substance for preventing hydrophilicity is fixed will be described. The production method in this case is basically based on the photo-excitation of a photocatalyst such as cobalt or a cobalt compound after coating and curing a coating composition containing photocatalyst particles and a water-repellent silicone precursor. By applying a solution containing a substance for preventing hydrophilization and fixing the solution to the surface.

Here, the coating composition has photocatalyst particles and a precursor of a water-repellent silicone as essential components, and in addition, a solvent such as water, ethanol, propanol, hydrochloric acid, nitric acid, and the like. Catalysts that promote the hydrolysis of silica precursors such as sulfuric acid, acetic acid and maleic acid, basic compounds such as tributylamine and hexylamine, and acidic compounds such as aluminum triisopropoxide and tetraisopropyl titanate Such as a catalyst for curing a precursor of silica,
A surfactant such as a silane coupling agent for improving the dispersibility of the coating liquid may be added.

[0022] Here silicone - The precursor emissions in the average composition formula _{R p SiX q O (4-} pq) / 2 ( wherein, R consists of one or more organic groups monovalent functional X or a functional group comprising two or more selected from a monovalent organic group and a hydrogen group, X is an alkoxy group or a halogen atom, and p and q are 0 <p <2, 0 <
a film-forming element composed of a siloxane represented by the following formula: q <4) or a general formula R _p SiX _4-p (where R is one or more monovalent organic groups) Wherein X is an alkoxy group or a halogen atom, and p is 1 or 2. A film-forming element comprising a hydrolyzable silane derivative to be
Can be suitably used.

Here, as the coating film forming element comprising the hydrolyzable silane derivative, methyltrimethoxysilane,
Methyltriethoxysilane, methyltripropoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, ethyltributoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, Phenyltributoxysilane,
Dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldipropoxysilane, dimethyldibutoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diethyldipropoxysilane, diethyldibutoxysilane, phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, phenyl Methyldipropoxysilane, phenylmethyldibutoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-propyltripropoxysilane, n-propyltributoxysilane, γ-glycoxydoxypropyltrimethoxysilane, γ -Acryloxypropyltrimethoxysilane and the like can be suitably used.

The film-forming element composed of the siloxane includes partial hydrolysis and dehydration-condensation polymerization of the hydrolyzable silane derivative, or a partial hydrolyzate of the hydrolyzable silane derivative, tetramethoxysilane, tetramethoxysilane and tetramethoxysilane. It can be produced by dehydration polycondensation with a partial hydrolyzate such as ethoxysilane, tetrapropoxysilane, tetrabutoxysilane, diethoxydimethoxysilane and the like.

The coating method of the above coating composition includes spray coating, dip coating, flow coating, spin coating, roll coating, brush coating, and sponge. A method such as coating can be suitably used. As a curing method, it can be carried out by polymerizing by heat treatment, standing at room temperature, ultraviolet irradiation, or the like.

The method of applying a solution containing a substance for preventing the photocatalyst such as cobalt or a cobalt compound from being hydrophilized by photoexcitation and fixing it on the surface includes, for example, cobalt chloride, cobalt sulfate, cobalt iodide, bromide, and the like. cobalt,
Spray coating method, dip coating method, flow coating method, spin coating method, roll coating method, brushing water-soluble cobalt compounds such as cobalt acetate, cobalt chlorate and cobalt nitrate Coating, sponge coating, etc., photoreduction, heat treatment, alcohol
This is performed by fixing by a method such as reduction using a sacrificial oxidizing agent such as toluene.

[0027]

【Example】

Reference example. Anatase type titanium oxide sol (Nissan Chemical, TA
-15, nitric acid peptized type, pH = 1), silica sol (Nippon Synthetic Rubber, Glasca A solution, pH = 4), methyltrimethoxysilane (Nippon Synthetic Rubber, Glasca B solution) and ethanol are mixed. The coating liquid obtained by stirring for 2 to 3 hours was applied on a 5 × 10 cm square glazed tile base material (TOTOKIKI, AB02E11) by spray coating.
A heat treatment was performed at 200 ° C. for 15 minutes to obtain a # 1 sample having a surface layer formed of 11 parts by weight of anatase type titanium oxide particles, 6 parts by weight of silica, and 5 parts by weight of silicone. The contact angle of the # 1 sample with water was 92 °. Here, the contact angle with water was evaluated using a contact angle measuring device (Kyowa Interface Science, CA-X150) by the contact angle with water 30 seconds after a water droplet was dropped from the micro syringe. Next, the surface of the # 1 sample was irradiated for one day with an ultraviolet illuminance of 0.3 mW / cm ² using an ultraviolet light source (Sankyo Electric, Black Light Blue (BLB) fluorescent lamp) to obtain a # 2 sample. As a result, the contact angle with water of the # 2 sample was hydrophilized to 0 °. Next, # 1 sample and #
One sample was irradiated with a mercury lamp at an ultraviolet irradiance of 22.8 mW / cm ² for 2 hours, and the surface of each of the # 3 samples obtained was subjected to Raman spectroscopic analysis. As a result, a peak of methyl group observed on the surface of sample # 1 was not observed in sample # 3, but a peak of hydroxyl group was observed instead. From the above,
It can be seen that the organic group bonded to the silicon atom in the silicon molecule on the surface of the film by the photoexcitation of the anatase type titanium oxide which is a photocatalyst is replaced by a hydroxyl group and becomes hydrophilic.

Embodiment 1 FIG. Anatase type titanium oxide sol (Nissan Chemical, TA-15, peptized nitrate, pH = 1),
Silica sol (Nippon Synthetic Rubber, Glasca A solution, pH = 4)
And methyltrimethoxysilane (Nippon Synthetic Rubber, Glasca B solution), cobalt chloride hexahydrate, and ethanol, and stirred for 2-3 hours. -Applied on a soda lime glass substrate of 10 cm square by a coating method and heat-treated at 150 ° C. for 15 minutes to obtain 11 parts by weight of anatase type titanium oxide particles, 6 parts by weight of silica,
A # 4 sample having a surface layer composed of 5 parts by weight of silicon and 0.2 parts by weight of cobalt was obtained. The contact angle of the # 4 sample with water was 95 °. Here, the contact angle with water was evaluated using a contact angle measuring device (Kyowa Interface Science, CA-X150) by the contact angle with water 30 seconds after a water droplet was dropped from the micro syringe. Next, the surface of the # 4 sample was irradiated with ultraviolet light of 0.3 mW / cm ² for one day using an ultraviolet light source (Sankyo Electric, Black Light Blue (BLB) fluorescent lamp), and # 5
A sample was obtained. As a result, the contact angle of the # 5 sample with water was still 92 °, maintaining water repellency. Therefore, from the above,
It can be seen that the hydrophilicity of the silicon on the surface of the coating film by photoexcitation of the anatase type titanium oxide as a photocatalyst is inhibited by cobalt. This is considered because the substitution of the hydroxyl group for the organic group bonded to the silicon atom in the silicon molecule on the surface of the coating is inhibited by cobalt.

Embodiment 2 FIG. Anatase type titanium oxide sol (Nissan Chemical, TA-15, peptized nitrate, pH = 1),
Silica sol (Nippon Synthetic Rubber, Glasca A solution, pH = 4)
And methyltrimethoxysilane (Nippon Synthetic Rubber, Glasca B liquid) and ethanol were mixed, and the mixture was stirred for 2 to 3 hours to obtain a coating liquid by spray coating.
Coated on a 0 cm square soda lime glass substrate,
Heat treated at 15 ° C. for 15 minutes to obtain anatase type titanium oxide particles 1
A surface layer consisting of 1 part by weight, 6 parts by weight of silica and 5 parts by weight of silicone was formed. Further, an aqueous solution of cobalt chloride hexahydrate having a cobalt metal concentration of 50 μmol / g was added to the solution.
After applying 3 g, an ultraviolet illuminance of 0.4 mW was obtained using an ultraviolet light source (Sankyo Electric, Black Light Blue (BLB) fluorescent lamp).
The sample was irradiated with ultraviolet rays of 10 cm / cm 2 for 10 minutes to fix cobalt on the substrate to obtain a # 6 sample. The contact angle of the # 6 sample with water is 9
It was 4 ゜. Here, the contact angle with water was evaluated using a contact angle measuring device (Kyowa Interface Science, CA-X150) by the contact angle with water 30 seconds after a water droplet was dropped from the micro syringe. Next, an ultraviolet light source (Sankyo Electric,
Black Light Bull (BLB) fluorescent lamp).
Irradiation was performed at 3 mW / cm ² ultraviolet irradiance for one day to obtain a # 7 sample. As a result, the contact angle with water of the # 7 sample was still 92 °, maintaining water repellency. Therefore, it can be understood from the above that the hydrophilicity of the silicon on the surface of the coating film due to the photoexcitation of the anatase type titanium oxide as a photocatalyst is inhibited by cobalt. This is considered because the substitution of the hydroxyl group for the organic group bonded to the silicon atom in the silicon molecule on the surface of the coating is inhibited by cobalt.

Embodiment 3 FIG. The # 5 sample, the # 7 sample, and a polytetrafluoroethylene plate for comparison were placed under the roofed part of the building as shown in FIG. 4 and left for 4 months. As a result, stains were observed on the polytetrafluoroethylene plate, whereas no stains were observed on the # 5 and # 7 samples.

[0031]

According to the present invention, a photocatalyst particle, a water-repellent silicone, and a substance for preventing the water-repellent silicone from becoming hydrophilic by photoexcitation of the photocatalyst are provided on the substrate surface on the inner wall of the tunnel. Or a layer containing photocatalyst particles and a water-repellent silicone is formed on the surface of the substrate, and at least a part of the surface of the layer has the water-repellent property. By fixing a substance for preventing hydrophilicity of the silicon by photoexcitation of the photocatalyst of the silicone, the surface of the member can maintain water repellency for a long period of time, so that the surface of the member is hardly stained permanently and high. The light output can be maintained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a tunnel lighting device.

FIG. 2 is a diagram showing a surface structure of a cover of the tunnel lighting device according to the present invention.

FIG. 3 is a diagram showing another surface structure of a cover of the tunnel lighting device according to the present invention.

FIG. 4 is a diagram showing a method for setting a test sample according to the embodiment of the present invention.

[Explanation of symbols]

 10: Tunnel lighting device 18: Cover glass 20: Surface layer

Claims (3)

[Claims] 1. A photocatalyst particle, a water-repellent silicone, and the water-repellent silicone on a cover surface of a tunnel lighting device.
A substantially transparent surface layer containing a material for preventing the photocatalyst from becoming hydrophilic due to photoexcitation of the photocatalyst. 2. A substantially transparent layer containing photocatalyst particles and a water-repellent silicone is formed on a surface of a cover of a tunnel lighting device, and at least a part of the surface of the layer has the water-repellent property. An illumination device for tunnels, wherein a substance for preventing hydrophilicity of silicon by photoexcitation of the photocatalyst is fixed. 3. The tunnel lighting device according to claim 1, wherein the substance for preventing the photocatalyst from becoming hydrophilic by photoexcitation is cobalt or a cobalt compound.