JPH11657A - Water purifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance portability and removal performance by forming on an inner surface of a transparent container a coating layer of a composition comprising inorganic particles having a photocatalytic action and an inorganic substance and/or a binder which has been converted into an inorganic substance. SOLUTION: A coating layer containing particles of an inorganic substance having a photocatalytic action, e.g. oxide semiconductor such as TiO2 and the like, is formed almost uniformly on a whole inner face of a transparent container 1. The coating layer is of a thickness of not more than 0.5 μm. The coating layer containing particles of the inorganic substance is formed of a composition comprising particles of the inorganic substance having an average size of not more than 0.01 μm and an inorganic substance and/or a binder which has been converted into an inorganic substance, e.g. alumina sol. The transparent container 1 is made of a material having an ultraviolet absorption ratio of less than 20%, e.g. glass and the like. By this constitution the coating layer has no possibility of being separated and transparency can be maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water purifier for removing components harmful to the human body and unpleasant odor from drinking water, particularly tap water. More specifically, the present invention relates to a simple water purifier using an oxide semiconductor activated by ultraviolet rays.

[0002]

2. Description of the Related Art Conventionally, as a simple water purifier, a method of removing foreign substances from water by installing tap water in a faucet and passing tap water through hollow fibers or activated carbon by fluid pressure, a method using a barite or a medical device in a container. There is known a method of decomposing or adsorbing and removing foreign matter in tap water by adding a functional stone such as a king stone.

[0003] However, in the former method, since the pressure of the water supply is required, the place of use is limited, and a separate container is required for storing. Moreover, since it is necessary to replace the filtration and adsorption unit, handling is complicated,
Running cost has become expensive. Further, in the latter method, although it is only necessary to leave the stone in the container, the effect is unclear and the variation is large because the stone is a natural stone.

[0004] In any of these methods, when stored as drinking water in a refrigerator or the like for a long period of time, it has been difficult to prevent the growth of bacteria because chlorine components having a bactericidal action have been removed.

[0005]

SUMMARY OF THE INVENTION In view of the above problems, the present invention has a structure capable of removing components harmful to the human body and unpleasant odor by simply storing drinking water in a container, and further forcing the inside. An object of the present invention is to provide a water purifier which is easy to carry by stirring and has excellent removability.

[0006]

Means for Solving the Problems As a result of repeated studies to solve the above problems, the present inventors have found that a coating layer containing inorganic particles having a photocatalytic action may be formed on the inner surface of a water purifier. The present invention has been completed.

That is, according to the present invention, the following water purifier is provided. (1) A water purifier provided with a coating layer made of a composition of inorganic particles having a photocatalytic action and an inorganic substance and / or a binder converted to an inorganic substance on an inner surface of a transparent container. (2) The water purifier according to the above (1), wherein an agitator driven indirectly from outside is mounted in the container. (3) The water purifier according to the above (1) or (2), wherein the inorganic particles are made of an oxide semiconductor. (4) The water purifier according to any one of the above (1) to (3), wherein the average particle diameter of the inorganic particles is 0.01 μm or less. (5) A coating layer having a thickness of 0.5 μm or less containing inorganic particles is provided on the inner surface of a transparent container having an ultraviolet absorptivity of less than 20%, and an irradiation source for irradiating the container with ultraviolet light is provided outside the container. The water purifier according to any one of (1) to (4) above.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view illustrating an embodiment of the present invention. In FIG. 1, 1 is a transparent container, and 2 is an upper lid. Any material can be used for the transparent container 1 as long as it has transparency. However, in consideration of the durability of the coating layer applied to the inner surface, the cost of the container, etc., materials such as glass, polycarbonate, and acrylic can be used. Is preferred. A material having an ultraviolet absorption of less than 20% is preferred. The upper lid 2 is usually made of a flexible general-purpose plastic, is detachable from the transparent container 1, and has a sealing property. Further, the upper lid 2 may be provided with a water spout 3 and a detachable cap 4 in some cases. A coating layer containing inorganic particles having a photocatalytic action is formed almost uniformly on the entire inner surface of the transparent container 1. The thickness of this coating layer is 0.5μ
m or less.

FIG. 2 is a sectional view showing another embodiment. In FIG. 2, 1 is a transparent container and 5 is a storage container. The storage container 5 is divided into a main body 5a and a lid 5b,
The main body 5a has a space 6 for accommodating equipment such as stirring. Basically, a stirrer 7, a stirrer 7,
UV light source 8, power source converter 9 for light source, battery 10, reflector 1
1 etc. are stored. Other than the part 5c of the storage container main body, a member that is not normally transparent is used. This is to prevent ultraviolet rays irradiated into the container from leaking to the outside. Further, the storage container main body portion facing the outside of the transparent container may be coated with a reflective material to improve the ultraviolet irradiation efficiency. One part 5c of the storage container body includes an ultraviolet light source 8
It is made of a material with good transparency (at least as good as or better than the material of the transparent container) in order to efficiently transmit the ultraviolet rays irradiated from the transparent container and make the ultraviolet light applied to the inorganic coating layer on the inner surface of the transparent container. The reflecting plate 11 is provided at the lower part of the shape of the ultraviolet lamp in order to apply the ultraviolet light to the coating layer averagely and efficiently. The stirrer 12 is a stirrer that stirs the inside of the transparent container 1 so that water efficiently contacts the coating layer,
It is indirectly driven by the magnetic force of the stirrer 7. Battery 10
Supplies power to the stirrer 7 and the ultraviolet light source 8, but this can be replaced by a household power supply. That is, when stored in a refrigerator, a switchable type such as using a battery and using a 100 volt power supply in other cases may be used.

FIG. 3 is a sectional view showing an application example of FIG. Although the number designation of each component is the same as that of FIG. 2, here, the ultraviolet ray 8 is installed on the lid 5b, and when the lid is closed, it enters the transparent container 1 and directly irradiates the coating layer. Therefore,
The part 5c of the storage container body does not need to be made of a transparent material. The power supply may be a battery or a home power supply.

FIG. 4a is a cross-sectional view illustrating another embodiment. In FIG. 4a, 1 is a transparent container and 2 is an upper lid. The transparent container 1 is rotated in one direction by a drive gear 12 installed in the storage container 5. In the storage container 5,
It has an instrument storage space 6 and a motor 17 inside.
The drive gear 12, the power converter 9 for the light source, the magnet 15a, and the like are housed. The storage container 5 is also provided with an ultraviolet light source 8. Reference numeral 16 denotes a spiral stirrer having a magnet 15b at the bottom thereof. When the transparent container 1 rotates, the magnet 15b is attracted to and fixed by the magnet 15a.
Moves relative to the wall surface of the transparent container, and consequently agitates water near the coating layer.

FIG. 4B is a plan view of the storage container 5 as viewed from above. The drive gear 12 transmits the rotational force of the motor 17 to the transparent container 1, and when the container rotates, the container 5 is provided with fourteen grooves so that the container does not deviate. The ultraviolet light source 8 is located on the side surface of the transparent container 1, so that the ultraviolet light does not uniformly hit the coating layer when the transparent container 1 is stationary, but the ultraviolet light is not efficiently emitted because the transparent container 1 is rotating. Well absorbed by the coating layer.

FIG. 4c is a partial perspective view showing a rotation mechanism of the transparent container 1. As shown in FIG. A toothed protrusion 13 corresponding to the drive gear 12 is provided at a lower portion of the transparent container 1. The toothed projection 13 fits into the groove 14 in FIG. 4b, preventing the transparent container from escaping during rotation.

In the water purifier of the present invention, the inner surface of the transparent container 1 shown in FIGS. 1 to 4 is composed of a composition of inorganic particles having a photocatalytic action and inorganic and / or a binder converted to inorganic. It is necessary that a coating layer is formed. The term “inorganic particles having a photocatalytic action (hereinafter abbreviated as photocatalytic particles)” as used in the present invention means that active oxygen is generated by irradiation of light such as ultraviolet rays, and many harmful substances and odorous substances are oxidized and decomposed to form a photooxidation catalyst. It means something that functions as
Therefore, the photocatalyst particles often belong to the category of the oxidizing photocatalyst. When such photocatalyst particles are used, deodorization can be performed by utilizing catalytic decomposition instead of a mere adsorption action, and thus the deodorizing or deodorizing effect is maintained for a long period of time. Furthermore, the photocatalyst particles not only decompose harmful substances and malodorous substances, but also have a bactericidal action and the like.

In general, various types of optical semiconductors can be used as the photocatalyst, whether organic or inorganic, but are often inorganic optical semiconductors.

In the present invention, it is preferable that the inorganic particles having photocatalysis (photocatalyst particles) are composed of an oxide semiconductor having a specific average particle diameter. As an oxide semiconductor, TiO ₂ , ZnO, WO ₃ , CdO, I
n ₂ O ₃ , Ag ₂ O, MnO ₂ , Cu ₂ O, Fe
Examples include ₂ O ₃ , V ₂ O ₅ , and SnO _2, and among them, TiO ₂ (titanium oxide) is particularly preferable. The crystal structure of the optical semiconductor constituting the inorganic particles is not particularly limited.
For example, in TiO ₂ , anatase type, brookite type,
Any of rutile type, amorphous type and the like may be used. Preferred TiO ₂ includes anatase type titanium oxide.

The most characteristic feature of the inorganic particles having a photocatalytic action of the present invention is that they have an extremely fine average particle diameter of 0.01 μm or less. In general, inorganic semiconductors having a photocatalytic function are used not only in sol and gel form but also in powder form, in which case the average particle size is 0.01 μm
Most of them exceed.

The binder in the composition used in the present invention is derived from an inorganic substance and / or a binder which can be converted into an inorganic substance, as will be described later. Although it is present in the composition in a form, it may be derived from a binder which can be converted to an inorganic substance, and also exists in the composition in a form converted to an inorganic substance. In addition, as long as it is a nominal amount that does not impair the purpose of the present invention, the organic binder may be contained in addition to the inorganic binder, but the organic binder is decomposed by the action of the inorganic particles having a photocatalytic action. Therefore, it is usually better not to use an organic binder.

Examples of the inorganic material and / or a binder that can be converted to an inorganic material include inorganic binders such as alumina sol and silica sol; tetramethoxysilane, tetraethoxysilane, trimethylmethoxysilane, methyltrimethoxysilane, methyltriethoxysilane. And other alkoxysilanes or oligomers thereof; other metal alkoxides; and the like. Alkoxysilanes are easily hydrolyzed to produce silanol groups, which are further crosslinked and converted to a composition of SiO ₂ .

In the water purifier of the present invention, the formation of the coating layer on the inner surface of the transparent container with the composition of the inorganic particles and the binder can be achieved as follows. That is, the inner surface of the transparent container, the inorganic particles having a photocatalytic action, a binder capable of converting to inorganic and or inorganic, and a coating composition having a medium for dispersing or dissolving them as a main component, and then dried. The operation is repeated one or more times. Contact can be made by coating, dipping,
It is performed by a spray method, a spin coating method, or the like.

As the medium, water, a water-miscible organic solvent, or a mixed solvent of water and a water-miscible organic solvent is used.
Particularly, a mixed solvent of water and an alcohol (methanol, ethanol, isopropanol, etc.) is preferable.

The solid content concentration in the coating composition is, for example, about 3 to 30% by weight, particularly about 5 to 20% by weight, but is not necessarily limited to this range. When the concentration is high, it may be used after diluting with the above-mentioned medium. The ratio of the inorganic particles to the binder in the coating composition was 20:80 by weight.
９５95: 5, preferably 30:70 to 90:10. When the ratio of the binder is too small, the coating layer easily peels off from the inner surface of the container, and when the ratio of the binder is too large, the deodorizing effect becomes insufficient.

The drying may be natural drying or forced drying. After drying, heat treatment may be performed as necessary. The heat treatment temperature depends on the heat treatment time, but it is a temperature up to about 300 ° C, usually 110 to 200 ° C, especially 120 to 160 ° C.
Often.

The formation of the coating layer on the inner surface of the transparent container is preferably limited to about 0.1 μm in one operation from the viewpoint of adhesion. However, since the deodorizing effect tends to be insufficient if only a single coating layer is formed on the inner surface of the container, the operation of contacting the inner surface of the container with the coating composition and then drying the coating is repeated a plurality of times to coat the inner surface of the container. It is particularly desirable that the thickness of the coating layer be 0.5 μm or less by forming a layer in multiple layers (overcoating).

If the above-mentioned coating operation is adopted, the coating layer is substantially transparent, and the coating layer does not peel off even by friction with the stirrer. The transparency of the container is maintained.

[0026]

As described above, according to the present invention, it is possible to provide a simple water purifier which has no restriction on the installation place, is convenient for handling, has a simple structure, and can be used with high efficiency for a long time.
It has a great industrial effect.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a water purifier of the present invention.

FIG. 2 is a cross-sectional view illustrating another water purifier of the present invention.

FIG. 3 is a cross-sectional view illustrating another water purifier of the present invention.

FIG. 4 is a sectional view (4) illustrating another water purifier of the present invention.
a), a plan view (4b), and a partial three-dimensional view (4C) showing the rotation mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transparency container 2 Top lid 5 Storage container 7 Stirrer 8 Ultraviolet light source 9 Power supply converter for light source 12 Drive gear

Claims (5)

[Claims] 1. A water purifier comprising, on the inner surface of a transparent container, a coating layer comprising a composition of inorganic particles having a photocatalytic action and an inorganic substance and / or a binder converted into an inorganic substance. 2. The water purifier according to claim 1, wherein a stirrer driven indirectly from outside is mounted in the container. 3. The water purifier according to claim 1, wherein the inorganic particles are made of an oxide semiconductor. 4. The water purifier according to claim 1, wherein the average particle size of the inorganic particles is 0.01 μm or less. 5. A transparent container having an ultraviolet absorptivity of less than 20%, a coating layer containing inorganic particles having a thickness of 0.5 μm or less is provided on an inner surface of the transparent container. The water purifier according to any one of claims 1 to 4, which is installed outside.