JPH09224800A - Glassware and water-washing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to wash the top face of the surface layer through a simple washing by providing thereon with a surface layer containing the transparent photo-catalytic oxide corpuscles so that the top face of the surface layer represents the hydrophile, corresponding to the photo-generation of the photo-catalyst. SOLUTION: A layer containing the photo-catalyst is formed over the top surface of the base material on the surfaces of glassware. Constructing this surface results in giving a high hydrophile corresponded to the photo-generation of the photo-catalyst. This produces the stronger hydrophile than the lipophile to facilitate an ease of washing the surfaces of the glassware with water. M stands for a metallic element. If the most top face consists of a general inorganic oxide, the oxide represents the hydrophile in a state of absorbing no contaminant in the environment so that activating the photo-generation of the photo catalyst (photo-catalytic titanium oxide) to be mixed into the surface layer other than any inorganic oxide, rejects any contaminant. Forming an absorption water film can produce an uniform water film. As a photo-catalyst, anatase-type titanium oxide, tin oxide and the like can be listed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to glass tableware (including glass cups), and particularly to tableware capable of easily removing dirt adhering to the surface thereof by washing with water or the like.

[0002]

2. Description of the Related Art Oily stains on food adhered to tableware are difficult to remove. In particular, glass tableware is transparent, so it stands out when dirt adheres. For this reason, a chemical method of immersing dishes in a neutral detergent or the like, floating oil on the surface, and then washing with water is used in ordinary households.

[0003]

The use of detergents to remove oil stains on tableware causes rough skin. Also,
In recent years, wastewater containing neutral detergent from households has become a problem as a cause of water pollution in rivers. Therefore, the purpose of the present invention is to
It is an object of the present invention to provide a glass dish having a surface that can be easily washed by rinsing with water or immersing in water, and a method for washing the same.

[0004]

SUMMARY OF THE INVENTION The present invention is based on the discovery that, in a member having a surface layer containing a photocatalyst formed thereon, when the photocatalyst is photoexcited, the surface of the member is highly hydrophilized. This phenomenon is considered to proceed by the following mechanism. That is, when the photocatalyst is irradiated with light having an energy larger than the energy gap between the valence band upper end and the conduction band lower end of the photocatalyst, the electrons in the valence band of the photocatalyst are excited to generate conduction electrons and holes. The action of either or both of them probably imparts polarity to the surface and collects polar components such as water and hydroxyl groups. Then, one or both of conduction electrons and holes and the above-mentioned polar component cooperate with each other to cut off a chemical bond between the surface and the contaminant chemically adsorbed on the surface, and to cause a chemical adsorbed water on the surface. Is adsorbed, and a physically adsorbed water layer is formed thereon. Further, once the surface of the member is highly hydrophilized, the hydrophilicity of the surface is maintained for a certain period even if the member is kept in a dark place.

The present invention provides easily washable glass tableware having a surface layer containing photocatalyst particles on the surface of a glass tableware substrate. By providing a surface layer containing a photocatalyst, the surface of the surface layer exhibits hydrophilicity in response to photoexcitation of the photocatalyst, so that the surface of the glass tableware can be easily washed by rinsing it with water or immersing it in water. Become.

In a preferred embodiment of the present invention, the surface layer further contains silica. By containing silica, the surface is likely to exhibit a high degree of hydrophilicity near a water wetting angle of 0 °, and the hydrophilicity retention when held in a dark place is improved. The reason seems to be related to the ability of silica to store water in its structure.

In a preferred embodiment of the present invention, the surface layer further contains a solid acid. When the solid acid is contained, the surface is likely to exhibit a high degree of hydrophilicity near a water wetting angle of 0 °, and the hydrophilicity retention when kept in a dark place is improved. The reason is that when a solid acid is contained in the surface layer, the polarity of the surface is large regardless of the presence or absence of light, so it is easier to selectively adsorb water molecules that are polar molecules than hydrophobic molecules. . Therefore, a stable physical adsorption water layer is easily formed, and even if it is kept in a dark place,
Surface hydrophilicity can be maintained at a high level for a fairly long time.

In a preferred embodiment of the present invention, the surface layer further contains silicone.
By containing silicone, by photoexcitation of the photocatalyst, at least a part of the organic group bonded to the silicon atom in the silicone is replaced with a hydroxyl group, and a physically adsorbed water layer is formed on the organic group, so that the surface is It exhibits a high degree of hydrophilicity close to a water wetting angle of 0 °, and improves the hydrophilicity maintaining ability when kept in a dark place.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a specific structure of the present invention will be described. On the surface of the glass tableware in the present invention,
As shown in FIG. 1 or FIG. 2, a layer containing a photocatalyst is formed on the surface of the substrate. By taking such a surface structure, the surface of the glass tableware is highly hydrophilized in response to photoexcitation of the photocatalyst. Thereby, the hydrophilicity of the surface becomes stronger than the lipophilicity. This makes it easy to wash the surface of the glass tableware with water.

In FIG. 1, when the surface layer comprises only a photocatalyst, the photocatalyst is preferably an oxide.
By doing so, the oxide shows hydrophilicity in the state where the pollutants in the environment are not adsorbed, so that the pollutants are rejected by the photoexcitation action and the adsorbed water layer is formed, so that the oxides easily exhibit hydrophilicity. A uniform water film can be formed. In FIG. 2, M represents a metal element. Therefore, in the case of FIG. 2, the outermost surface is made of a general inorganic oxide. Again,
Since the oxide shows hydrophilicity in a state where the pollutant in the environment is not adsorbed, the pollutant is rejected by a photoexcitation effect of a photocatalyst mixed into the surface layer other than the inorganic oxide,
By forming the adsorbed water layer, a uniform water film can be formed.

A photocatalyst is a photocatalyst of an electron in the valence band when irradiated with light (excitation light) having an energy (that is, a short wavelength) larger than the energy gap between the conduction band and the valence band of the crystal. A substance that is excited (photoexcited) to generate conduction electrons and holes. For example, anatase-type titanium oxide, rutile-type titanium oxide, tin oxide, zinc oxide, dibismuth trioxide, tungsten trioxide, oxide trioxide. Diiron, strontium titanate and the like can be preferably used. Here, as a light source used for photoexcitation of the photocatalyst, a fluorescent lamp, an incandescent lamp, a metal halide lamp, a black light lamp, a xenon lamp, a mercury lamp, sunlight, and the like can be suitably used. In order to make the surface of the base material highly hydrophilic by photoexcitation of the photocatalyst, the illuminance of the excitation light is 0.001 mW /
cm ² suffices above, but preferably that it 0.01 mW / cm ² or more, and more preferably it 0.1 mW / cm ² or more.

The thickness of the surface layer containing the photocatalyst is 0.4
It is preferable that the thickness is less than or equal to μm. Then, white turbidity due to irregular reflection of light can be prevented, and the surface layer becomes substantially transparent. More preferably, the thickness of the surface layer containing the photocatalyst is 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. The surface of the surface layer may be further provided with a wear-resistant or corrosion-resistant protective layer capable of being made hydrophilic and other functional films.

The surface layer preferably has a refractive index not so high as compared with the substrate. Preferably, the refractive index of the surface layer is 2 or less. Then, light reflection at the interface between the substrate and the surface layer and the interface between the surface layer and air can be suppressed. In order to reduce the refractive index of the surface layer to 2 or less, a substance having a refractive index of 2 or less is used for the photocatalyst, or if the photocatalyst has a refractive index of 2 or more, another substance having a refractive index of 2 or less is used for the surface layer. To be added. As a photocatalyst having a refractive index of 2 or less, tin oxide (refractive index: 1.9) or the like can be used. 2
As the photocatalyst having the above refractive index, there are anatase type titanium oxide (refractive index 2.5) and rutile type titanium oxide (refractive index 2.7). In this case, other substances having a refractive index of 2 or less, For example, calcium carbonate (refractive index 1.6), dolomite (refractive index 1.7), magnesium carbonate (refractive index 1.5), calcium hydroxide (refractive index 1.6), strontium carbonate (refractive index 1.5). ), Magnesium fluoride (refractive index 1.4), calcium fluoride (refractive index 1.
4), silica (refractive index 1.5), alumina (refractive index 1.
6), silica sand (refractive index 1.6), kaolin (refractive index 1.
6), montmorillonite (refractive index 1.5), sericite (refractive index 1.6), zeolite (refractive index 1.6), tin oxide (refractive index 1.9) and the like may be added to the surface layer.

A metal such as Ag, Cu, or 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.

The surface layer includes Pt, Pd, Ru, R
A platinum group metal such as h, Ir, Os can be added. The surface layer to which the metal is added can enhance the oxidation-reduction activity of the photocatalyst and improve the deodorizing and purifying action and the like. In addition, when a solid acid is added in addition to the photocatalyst, the acidity of the solid acid is improved by the addition of a platinum group metal, so that the hydrophilicity is also improved, and the formation of a water film on the attached water is further promoted. The hydrophilicity when the excitation light is not irradiated to the photocatalyst for a long period of time is also improved. Mo may be added to the surface layer. Also in this case, when a solid acid is added in addition to the photocatalyst, the acidity of the solid acid is improved, so that the hydrophilicity retention property is also improved, the water film of the attached water is further promoted, and the photocatalyst is excited for a long period of time. Is also improved when not irradiated.

When the substrate is glass containing alkali network modifying ions such as sodium (soda lime glass, parallel plate glass, etc.), an intermediate layer such as silica may be formed between the substrate and the surface layer. Good. Then, the diffusion of the alkali network modifying ions from the base material to the surface layer during the firing is prevented, and the photocatalytic function is more effectively exhibited.

The term "hydrophilic" refers to the property of being easily conformed when water is dropped on the surface, and generally refers to a state where the water wetting angle is less than 90 °. The term “high hydrophilicity” in the present invention refers to a property that is highly compatible when water is dropped on the surface, and more specifically, a state where the water wetting angle is about 10 ° or less. In particular, PCT / JP96 / 0 for easy cleaning with water
As disclosed in 0734, the water wetting angle is preferably 10 ° or less, more preferably 5 ° or less.

The solid acid in the present invention means an acid containing a solid oxide as a constituent element, specifically, sulfuric acid-supporting Al ₂
O ₃ , sulfuric acid supported TiO ₂ , sulfuric acid supported ZrO ₂ , sulfuric acid supported S
nO ² , sulfuric acid supported Fe ₂ O ₃ , sulfuric acid supported SiO ₂ , sulfuric acid supported HfO ₂ , TiO ₂ / WO ₃ , WO ₃ / SnO ₂ , WO ₃ / Z
_{rO 2, WO 3 / Fe 2} O 3, SiO 2 · Al 2 O 3, TiO 2
/ SiO ₂ , TiO ₂ / ZrO ₂ , TiO ₂ / Al ₂ O _{3 and the} like can be preferably used.

Next, a method for forming the surface layer will be described. First, the production method in the case where the surface layer is composed only of the photocatalyst will be described by taking the case where the photocatalyst is anatase type titanium oxide as an example. In this case, there are roughly three methods. One method is a sol coating and firing method, the other method is an organic titanate method, and the other method is an electron beam evaporation method. (1) Sol-coating and firing method Anatase-type titanium oxide sol is applied to the surface of a substrate by a method such as spray coating, dip coating, flow coating, spin coating, or roll coating, and then fired. (2) Organic titanate method Titanium alkoxide (tetraethoxy titanium, tetramethoxy titanium, tetrapropoxy titanium, tetrabutoxy titanium, etc.), titanium acetate, titanium chelate, etc. are added with a hydrolysis inhibitor (hydrochloric acid, ethylamine, etc.). , After diluting with a non-aqueous solvent such as alcohol (ethanol, propanol, butanol, etc.), while partially or completely proceeding the hydrolysis, the mixture is spray-coated, dip-coated, Apply by methods such as flow coating method, spin coating method, roll coating method,
dry. By drying, the hydrolysis of the organic titanate is completed to produce titanium hydroxide, and a layer of amorphous titanium oxide is formed on the surface of the base material by dehydration-condensation polymerization of the titanium hydroxide. Thereafter, the amorphous titanium oxide is calcined at a temperature equal to or higher than the crystallization temperature of anatase to cause a phase transition from the amorphous titanium oxide to the anatase titanium oxide. (3) Electron beam evaporation method An amorphous titanium oxide layer is formed on the surface of a substrate by irradiating a titanium oxide target with an electron beam. After that, firing at a temperature higher than the crystallization temperature of anatase,
Phase transition of amorphous titanium oxide to anatase titanium oxide.

Next, the case where the surface layer is composed of a photocatalyst and silica will be described by taking the case where the photocatalyst is anatase type titanium oxide as an example. In this case, for example, there are the following three methods. One method is the sol coating firing method, the other is the organic titanate method, the other is 4
This is a functional silane method. (1) Sol coating and baking method A mixture of anatase-type titanium oxide sol and silica sol is applied to the substrate surface by a method such as a spray coating method, a dip coating method, a flow coating method, a spin coating method, and a roll coating method, and then fired. I do. (2) Organic titanate method Titanium alkoxides (tetraethoxytitanium, tetramethoxytitanium, tetrapropoxytitanium, tetrabutoxytitanium, etc.), titanium acetate, titanium chelate, and other organic titanates are added with a hydrolysis inhibitor (hydrochloric acid, ethylamine, etc.) and silica sol. Add alcohol (ethanol,
After diluting with a non-aqueous solvent such as propanol, butanol, etc., and then allowing the hydrolysis to proceed partially or completely, the mixture is spray-coated, dip-coated, flow-coated,
It is applied by a method such as spin coating or roll coating and dried. By drying, the hydrolysis of the organic titanate is completed to produce titanium hydroxide, and a layer of amorphous titanium oxide is formed on the surface of the base material by dehydration-condensation polymerization of the titanium hydroxide. Thereafter, the amorphous titanium oxide is calcined at a temperature equal to or higher than the crystallization temperature of anatase to cause a phase transition from the amorphous titanium oxide to the anatase titanium oxide. (3) Tetrafunctional silane method A mixture of tetraalkoxysilane (tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, tetramethoxysilane, etc.) and anatase type titanium oxide sol is spray-coated or dip-coated on the surface of a substrate. , A flow coating method, a spin coating method, a roll coating method, or the like, and if necessary, hydrolyzing to form silanol, and then silanol is subjected to dehydration condensation polymerization by a method such as heating.

Next, the case where the surface layer is composed of a photocatalyst and a solid acid will be described by taking as an example the case where the photocatalyst is anatase type titanium oxide and the solid acid is TiO ₂ / WO ₃ . One method in this case is a method in which an ammonia solution of tungstic acid and an anatase type titanium oxide sol are mixed, and if necessary, a mixture diluted with a diluent (water, ethanol, etc.) is spray-coated on the surface of the base material, It is applied by a method such as a dip coating method, a flow coating method, a spin coating method or a roll coating method, and baked. Other methods include electron beam evaporation, titanium alkoxide, titanium acetate, hydrolysis of organic titanates such as titanium chelates, and dehydration polycondensation to form an amorphous titanium oxide film, and then tungstic acid is applied. Heat treatment is performed at a temperature at which amorphous titanium oxide is crystallized and a TiO ₂ / WO ₃ composite oxide is formed.

Next, the case where the surface layer is composed of a photocatalyst and silicone will be described by taking the case where the photocatalyst is anatase type titanium oxide as an example. The method in this case is to mix a coating composed of uncured or partially cured silicone or a precursor of silicone and anatase type titanium oxide sol, and hydrolyze the precursor of silicone as needed, and then mix the mixture. Spray coating method on the surface of the substrate,
It is applied by a method such as a dip coating method, a flow coating method, a spin coating method, a roll coating method, etc., and a hydrolyzate of a silicone precursor is subjected to dehydration polycondensation by a method such as heating to obtain anatase type titanium oxide particles. A surface layer made of silicone is formed. The formed surface layer, by photoexcitation of anatase type titanium oxide by irradiation with light including ultraviolet rays, at least a part of the organic group bonded to the silicon atom in the silicone molecule is substituted with a hydroxyl group, and further on it. A physically adsorbed water layer is formed,
It exhibits a high degree of hydrophilicity. Here, the precursor of silicone includes methyltrimethoxysilane, methyltriethoxysilane, methyltributoxysilane, methyltripropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltributoxysilane, ethyltripropoxysilane, and phenyl. Trimethoxysilane, phenyltriethoxysilane, phenyltributoxysilane,
Phenyltripropoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldibutoxysilane, dimethyldipropoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, diethyldibutoxysilane, diethyldipropoxysilane, phenylmethyldimethoxysilane, phenylmethyl Diethoxysilane, phenylmethyldibutoxysilane, phenylmethyldipropoxysilane, γ-glycidoxypropyltrimethoxysilane, a hydrolyzate thereof, and a mixture thereof can be suitably used.

[0023]

【Example】

Embodiment 1 FIG. Tetraethoxysilane (Wako Pure Chemical Industries) 0.69
g and anatase type titanium oxide sol (NISSAN CHEMICAL, TA-1
5, average particle size 10 nm) 1.07 g and ethanol 29.
88 g and 0.36 g of pure water were mixed to prepare a coating liquid. This coating liquid was applied on a 10 cm square glass substrate by a flow coating method. By holding this glass plate at a temperature of about 150 ° C. for about 20 minutes, tetraethoxysilane is subjected to hydrolysis and dehydration polycondensation, and a coating in which anatase-type titanium oxide particles are bound with amorphous silica is applied to the glass plate. Formed on the surface. The weight ratio of titanium oxide to silica in this coating is 1
Met. After leaving this glass plate in the dark for several days, it is then exposed to an ultraviolet light source (Sankyo Denki, Black Light Blue (BLB)).
A # 1 sample was obtained by irradiating the surface of the sample with ultraviolet light for about 1 hour at a UV intensity of 0.5 mW / cm ² using a fluorescent lamp.
For comparison, a # 2 sample in which a 10 cm square glass plate was left in the dark for several days was also prepared. First, a water drop was dropped on the # 1 sample and the # 2 sample, and the state after the drop was observed and the contact angle with water was measured. Here, the contact angle with water was evaluated using a contact angle measuring device (Kyowa Interface Science, CA-X150) based on the contact angle with water 30 seconds after dropping. As a result, when a water drop was dropped from the micro syringe onto the sample surface, it was observed that the water droplet spread uniformly on the sample surface in a water film shape. Further, the contact angle with water after 30 seconds was highly hydrophilized to about 0 °. On the other hand, in the case of the # 2 sample, when a water drop was dropped on the sample surface from the microsyringe, the water droplet adapted to the surface but did not reach a uniform water film state. The contact angle with water after 30 seconds was 30 °.
Next, the # 1 sample and the # 2 sample were blown to examine whether or not clouding occurred. As a result, fogging occurred in the # 2 sample, but no fogging occurred in the # 1 sample. Further, the # 1 sample was left in a dark place for two days thereafter, to obtain a # 3 sample. Then, for the # 3 sample, the contact angle with water was similarly measured by a contact angle measuring device. As a result, when a water drop was dropped on the sample surface from the microsyringe on the # 3 sample, it was observed that the water droplet spread uniformly on the sample surface like a # 1 sample. The contact angle with water was maintained at about 3 °.
Next, the presence or absence of fogging after spraying was observed for the # 3 sample. As a result, no fogging was observed.

Next, oleic acid was applied to the surfaces of the # 3 sample and the # 2 sample, and each sample was immersed in water filled in a water tank while keeping the sample surfaces in a horizontal posture. as a result,#
In the two samples, oleic acid remained attached to the surface,
Even with a slight rubbing, oleic acid only extended the sample surface. On the other hand, in the # 3 sample, the oleic acid became round, and when lightly rubbed, it separated from the surface.

Next, 1 part by weight of hydrophobic carbon black,
A slurry was prepared by suspending a powder mixture consisting of 1 part by weight of hydrophilic carbon black in water at a concentration of 1.05 g / liter. 150 ml of the above slurry was made to flow down on a # 3 sample inclined at 45 degrees and dried for 15 minutes, then 150 ml of distilled water was made to flow down and dried for 15 minutes, and this cycle was repeated 25 times. The change in color difference before and after the test was measured using a color difference meter (Tokyo Denshoku). The color difference was evaluated according to Japanese Industrial Standards (JIS) H0201 using ΔE * notation. As a result, the color difference change of the # 3 sample before and after the test was 0.
There was almost no change from 6.

Example 2 Amorphous titanium oxide was crystallized by depositing an amorphous titanium oxide film on the surface of a 10 cm square soda lime glass plate by an electron beam vapor deposition method and then firing it at a temperature of 500 ° C. Then, anatase type titanium oxide was produced. The film thickness of the anatase type titanium oxide film was 100 nm. Further, tungstic acid dissolved in 25% ammonia water was applied thereon to convert the weight of tungstic acid to 0.6 μg / cm ² , and then 500
Firing at a temperature of ° C. Next, after leaving this glass plate in the dark for several days, the surface of the sample was irradiated with ultraviolet rays for about 1 hour using a BLB fluorescent lamp at an ultraviolet illuminance of 0.5 mW / cm ² to obtain a # 4 sample. . For comparison, a # 2 sample of Example 1 in which a 10 cm square glass plate was left in the dark for several days was also prepared. First, a water drop was dropped on the # 4 sample and the # 2 sample, and the state after the drop was observed and the contact angle with water was measured. Here, the contact angle with water is measured using a contact angle measuring instrument (Kyowa Interface Science, CA-
X150) was used and the contact angle with water was evaluated 30 seconds after the dropping. As a result, it was observed that when water droplets were dropped from the microsyringe on the sample surface of the # 4 sample, the water droplets spread uniformly on the sample surface in the form of a water film. Further, the contact angle with water after 30 seconds was highly hydrophilized to about 0 °. On the other hand, in the case of the # 2 sample, when a water drop was dropped on the sample surface from the microsyringe, the water droplet adapted to the surface but did not reach a uniform water film state. The contact angle with water after 30 seconds was 30 °. Next, # 4 sample and #
Two samples were blown to examine whether or not clouding occurred. As a result, the # 2 sample generated haze, whereas the # 4 sample did not. Further, the # 4 sample was left in a dark place for two days thereafter to obtain a # 5 sample. Then, for the # 5 sample, the contact angle with water was similarly measured by a contact angle measuring device. As a result, when a water droplet was dropped on the sample surface from the microsyringe on the # 5 sample, it was observed that the water droplet spread uniformly over the sample surface in the form of a water film, similarly to the # 4 sample. The contact angle with water was maintained at about 1 °. Next, with respect to the # 5 sample, it was observed whether or not clouding occurred after the breathing. As a result, no fogging was observed.

Next, oleic acid was applied to the surfaces of the # 5 sample and the # 2 sample, and each sample was immersed in water filled in a water tank while keeping the sample surfaces in a horizontal posture. as a result,#
In the two samples, oleic acid remained attached to the surface,
Even with a slight rubbing, oleic acid only extended the sample surface. On the other hand, in the # 5 sample, the oleic acid became round, and lightly rubbed off the surface.

Next, 1 part by weight of hydrophobic carbon black,
A slurry was prepared by suspending a powder mixture consisting of 1 part by weight of hydrophilic carbon black in water at a concentration of 1.05 g / liter. 150 ml of the above slurry was made to flow down on a # 5 sample inclined at 45 degrees and dried for 15 minutes, then 150 ml of distilled water was made to flow down and dried for 15 minutes, and this cycle was repeated 25 times. The change in color difference before and after the test was measured using a color difference meter (Tokyo Denshoku). The color difference was evaluated according to Japanese Industrial Standards (JIS) H0201 using ΔE * notation. As a result, the color difference change of the # 5 sample before and after the test was 0.
There was almost no change from 4.

[0029]

According to the present invention, the surface of glass tableware is provided with a surface layer containing substantially transparent photocatalytic oxide particles, so that the surface of the surface layer becomes hydrophilic in response to photoexcitation of the photocatalyst. Present. As a result, the surface of the surface layer can be cleaned by simple washing such as rinsing with water or immersion in water.

[Brief description of drawings]

FIG. 1 is a diagram showing a surface structure of glass tableware according to the present invention.

FIG. 2 is a diagram showing another surface structure of the glass tableware according to the present invention.

Claims (8)

[Claims] 1. A surface layer containing photocatalyst particles is provided on the surface of a glass tableware substrate, and in response to photoexcitation of the photocatalyst,
The easily washable glass tableware in which the surface of the layer exhibits hydrophilicity and thus the surface of the layer of the glass tableware can be easily washed with water. 2. The glass tableware according to claim 1, wherein the surface layer further contains silica. 3. The glass tableware according to claim 1, wherein the surface layer further contains a solid acid. 4. The glass tableware according to claim 1, wherein the surface layer further contains silicone. 5. The surface of the surface layer exhibits hydrophilicity of 10 ° or less in terms of contact angle with water in response to photoexcitation of the photocatalyst. Glass tableware. 6. The surface of the surface layer exhibits hydrophilicity of 5 ° or less in terms of contact angle with water in response to photoexcitation of the photocatalyst. Glass tableware. 7. The method according to claim 1, wherein a protective layer capable of being made hydrophilic is further provided on the surface of the surface layer.
The glass tableware according to 6. 8. A step of preparing the glass tableware according to claim 1; and a step of making the surface of the layer hydrophilic by photoexciting a photocatalyst contained in a surface layer of the glass tableware. A method of washing glass tableware, comprising the steps of rinsing the glass tableware with water or immersing it in water to release deposits and / or contaminants adhering to the surface of the layer from the surface and wash away with water.