JPH09179197A - Reader and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and surely improve the distinctness and the cleanness of a light receiving plate and to lighten maintenance care by providing a reader main body constituted to read an original, and an optical catalyst film having light transmitting property and formed on at least either of the inner and the outer surfaces of the light receiving plate. SOLUTION: A copying machine 1 incorporates exposure, developing and fixing devices in a copying machine main body 2 so as to copy the original placed on a contact glass 3 being the light receiving plate receiving light from a read light source on copying paper. Then, the optical catalyst film 5 having the light transmitting property is formed nearly all over the outer surface of the contact glass 3. The film 5 is formed to be a thin film of at least one compound such as titanium oxide or iron oxide. When the film 5 is irradiated by a room lamp, electrons are discharged and an electron hole is formed on the film 5. Therefore, conductivity is increased, so that electrostatic charge amount is decreased to restrain or prevent static electricity from being generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document reading device such as a copying machine, a scanner, a facsimile, an overhead projector (hereinafter referred to as OHP), a liquid crystal OHP,
The present invention relates to projection devices such as slide projectors and projection televisions.

[0002]

2. Description of the Related Art Conventionally, a document reading device such as a copying machine,
A projection device such as an OHP has an original placed on a contact glass, which is a light receiving plate that receives light from a light source for reading or projecting, which is built in the main body of the device, reads the original, and copies it to a copy sheet. Alternatively, the document is projected on the screen.

[0003]

However, in such a conventional reading device and OHP, the user does not copy the original on the outer surface of the contact glass which receives light from the reading or projecting light source built in the main body. Will be placed, so at that time,
When the user directly touches the outer surface of the contact glass and stains it with sebum or the like to make it cloudy, the sharpness is deteriorated, and moreover, it is often stained with organic compounds such as cigarette smoke, mildew and malodor.
Also, if the inner surface of the contact glass is used for a long period of time, dust is often adsorbed and contaminated by static electricity or the like.

Therefore, it is necessary to regularly perform maintenance for cleaning the inner and outer surfaces of the contact glass in order to remove these stains.

By the way, in recent years, an invention of a method for purifying air by a photocatalyst such as titanium oxide having antifouling properties such as decomposing and removing organic substances, antifungal properties, and deodorizing properties has been published internationally (WO 94 / 11092).

However, there is no disclosure in this publication that light is transmitted through the photocatalyst, and the photocatalyst is formed on the contact glass of a reading device such as a copying machine or a projection device such as an OHP. It is unclear whether a technology that improves both sharpness and cleanliness and reduces maintenance is feasible.

Therefore, an object of the present invention is to form a photocatalytic film on a light receiving plate such as a contact glass, and easily impart antifouling property, antifungal property, and deodorant property to the light receiving plate to improve the sharpness of the light receiving plate. (EN) It is possible to provide a reading device and a projection device that can improve cleanliness easily and surely and reduce maintenance.

[0008]

According to a first aspect of the present invention, there is provided a main body of a reading device, which is constructed so that an original is placed on an outer surface of a light receiving plate which receives light from a reading light source and the original can be read. And a light-transmitting photocatalytic film formed on at least one of the inner and outer surfaces of the light receiving plate.

In the present invention, the photocatalyst film has a transmittance of a part of visible light (in the wavelength range of 380 to 780 nm) of 8
Desirably, it is 0% or more.

Therefore, according to the present invention, when the translucent photocatalytic film of the light receiving plate of a reading device such as a copying machine or a scanner is irradiated with room light or near-ultraviolet light in natural light, electrons are emitted by the photocatalytic film. As a result, holes are generated. Therefore, the conductivity of the light receiving plate is increased, so that the amount of charge can be reduced and the generation of static electricity can be suppressed or prevented. For this reason, it is possible to reduce or prevent dust, cigarettes, and other organic substances such as hand oil, mold, and malodorous substances from being attracted by static electricity and adhering to the light receiving plate.

Further, active electrons and holes of the photocatalyst film react with organic substances such as hand oil, mold and malodor, or react with water to generate active OH radicals when the tobacco adheres to the light receiving plate. The generated OH radicals react with an organic substance to decompose and can be removed. That is, the photocatalytic film has antifouling property, antifungal property, and deodorant property. Moreover, the photocatalyst film itself such as titanium oxide is harmless to the human body and has a light-transmitting property, so that it is possible to prevent the brightness of the light-receiving plate from decreasing.

Therefore, according to the present invention, the light-receiving plate is reduced or prevented from being contaminated by dust or organic substances,
Both the sharpness and cleanliness of the light receiving plate can be improved. As a result, maintenance for cleaning the light receiving plate can be reduced.

According to a second aspect of the present invention, the photocatalytic film is formed as a thin film of at least one compound of titanium oxide, iron oxide, tungsten oxide, zinc oxide and strontium titanate.

The photocatalyst film may be formed by dip coating a liquid in which metal oxide fine particles having a photocatalytic action are suspended, hydrolysis of metal alkoxide, sol-gel method, chemical vapor deposition, vacuum vapor deposition. There are laws etc.

According to the third aspect of the present invention, an adhesive or protective layer containing silicon dioxide as a main component is formed between the light receiving plate and the photocatalytic film.

Therefore, according to the present invention, the photocatalyst film can be strongly adhered to the light receiving plate with the adhesive containing silicon dioxide as a main component, or the light receiving plate can be protected by the protective layer.

According to a fourth aspect of the present invention, there is provided a main body of a projection device, which is configured so that a document is placed on an outer surface of a light receiving plate that receives light from a light source for projecting and the document is projected on a screen; And a light-transmitting photocatalytic film formed on at least one of the inner and outer surfaces of the light receiving plate.

Therefore, according to the present invention, the light receiving plate of the projection device such as OHP can be provided with antifouling property, antifungal property and deodorant property by substantially the same action as that of the photocatalyst film of the reading device according to the first aspect. it can. Therefore, the sharpness and cleanliness of the light receiving plate can be improved, and the maintenance for cleaning the light receiving plate can be reduced.

According to a fifth aspect of the projection apparatus, the photocatalyst film is formed as a thin film of at least one compound of titanium oxide, iron oxide, tungsten oxide, zinc oxide and strontium titanate.

The projection device according to a sixth aspect of the invention is characterized in that an adhesive or a protective layer containing silicon dioxide as a main component is formed between the light receiving plate and the photocatalytic film.

The projection device of claim 7 is characterized in that a photocatalytic film is formed on an image projection surface of a screen on which an image is projected.

Therefore, according to the present invention, the photocatalytic film can impart antifouling property, antifungal property and deodorant property to the projection surface of the screen, so that both the sharpness and the cleanliness of the screen can be improved. Therefore, maintenance for cleaning the light receiving plate can be reduced.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 4, the same or corresponding parts are designated by the same reference numerals.

FIG. 1 is a perspective view of a main part of a copying machine 1 according to a first embodiment of a reading device according to the present invention. The copying machine 1 includes a main body 2 of the copying machine, which includes an exposure light source (not shown) and a developing device. A built-in fixing device and the like are adapted to copy an original placed on a contact glass 3 which is a light receiving plate for receiving light from a reading light source onto a copy sheet. Reference numeral 4 is a pressure plate that covers the outer surface of the contact glass and can be opened and closed. Then, as shown in FIG. 2 (A), a translucent photocatalyst film 5 is formed almost entirely on the outer surface of the contact glass 3.

Next, a method of forming the photocatalyst film 5 will be described. As one example, first, at least one compound of titanium oxide, iron oxide, tungsten oxide, zinc oxide, and strontium titanate is dissolved in alcohol to prepare a metal alkoxide solution.

Next, the outer surface of the glass plate for the contact glass 3 is dipped in this metal alkoxide solution and pulled up at a constant speed to form a thin film on the surface of the glass plate.

The solvent alcohol evaporates from this film,
Further, as shown in the following [Reaction Formula 1], the group reacting with moisture in the air is evaporated as alcohol to form a gel-like transparent film.

[0028]

[Equation 1]

Next, when the gel-like film is fired in the atmosphere, the reaction of the following [Reaction formula 2] occurs to form the translucent photocatalytic film 5.

[0030]

[Equation 2]

The film thickness of the photocatalyst film 5 formed by this method can be appropriately controlled by the viscosity of the metal alkoxide solution, the metal oxide concentration, and the pulling rate from the metal alkoxide solution. The metal alkoxide solution may be applied to both inner and outer surfaces of the glass plate for the contact glass 3 by this dipping method.

As another method for forming the photocatalyst film 5, the above metal alkoxide solution is uniformly applied by spin coating onto the outer surface of the rotating contact glass 3 and dried to 700 ° C. The titanium oxide film containing a strong anatase type crystal, that is, the translucent photocatalytic film 5 can be formed by baking for 15 minutes.

However, when the contact glass 3 is made of a resin such as an acrylic plate, an organic silicon resin is undercoated on the outer surface of the resin plate, and an organic silicon compound is alcoholized on the undercoating. Then, a solution in which titanium dioxide powder is dispersed is applied and dried to form the photocatalyst film 5.

When the photocatalyst film 5 is irradiated with room light or near ultraviolet rays in natural light, electrons are emitted from the photocatalyst film 5 to generate holes. For this reason, the conductivity increases, so that the amount of charge can be reduced and the generation of static electricity can be suppressed or prevented.

For this reason, it is possible to reduce or prevent the generation of static electricity on the contact glass 3,
It is possible to prevent or prevent the adhesion of organic substances such as mold, hand fat, and malodorous substances to the photocatalyst film 5 due to static electricity, and to improve the antifouling property.

Further, even if a little bit of cigarette oil such as hand fat, mold, malodorous substance, etc. adheres, when the photocatalyst film 5 is exposed to near-ultraviolet light in a room light or natural light, electrons are emitted in the photocatalyst film 5. Since they are released and holes are generated, the active electrons and holes react with organic substances such as hand oil, mold, malodor, etc. of cigarettes, or react with water to generate active OH radicals. The OH radical reacts with an organic substance, decomposes, and can be removed. That is, the photocatalyst film 5 can exhibit antifouling property, antifungal property, and deodorant property. Moreover, the titanium oxide itself, which is the composition of the photocatalyst film 5, is not harmful to the human body, and the photocatalyst film 13 is translucent, so that the decrease in brightness of the light receiving plate 3 can be suppressed.

The photocatalyst film 5 may be formed on both inner and outer surfaces as shown in FIG. 2B, and further, as shown in FIG.
As shown in (A) and (B), a layer 6 containing silicon dioxide as a main component is interposed between the outer surface or both inner and outer surfaces of the light receiving plate 3 and the photocatalyst film 5 as an adhesive layer or a protective layer, respectively. You may let me. According to this, the photocatalytic film 5 can be strongly fixed to the light receiving plate 3.

FIG. 4 is a perspective view of a main part of an OHP (overhead projector) which is an embodiment of the projection apparatus according to the present invention.
A projection light source such as a metal halide lamp (not shown) and an optical system are built in, and an original document (not shown) placed on a contact glass 13 which is a light receiving plate for receiving light from the projection light source is projected on a screen (not shown). It has become.

Then, a translucent photocatalytic film 14 is formed almost entirely on at least one of the outer surface and the inner surface of the contact glass 13.

The translucent photocatalyst film 14 is formed by a film forming method similar to that of the photocatalyst film 5 of the copying machine 1 described above, and therefore has the same effect.

That is, the photocatalyst film 14 imparts antifouling property, antifungal property and deodorant property to the contact glass 13, and the titanium oxide itself which is the composition of the photocatalyst film 14 is harmless to the human body. Since it has a light-transmitting property, the decrease in brightness on the contact glass 13 can be substantially suppressed.

The photocatalytic film may be formed on the projection surface of a projection-type, transmissive-type, or reflection-type screen (not shown) on which an image of the OHP 11 or a liquid crystal projector (not shown), a slide projector, a projection television, etc. is projected. Good.

According to this, by irradiating these screens with, for example, near-ultraviolet rays in an interior light, the screens are provided with antifouling property, antifungal property and deodorant property, so that the projection surface of the screen is cleaned. It is possible to reduce maintenance, such as reducing the number of times to perform. This effect of reducing maintenance is remarkable for large screens used in movie theaters and the like.

After the screening is finished, the screen is irradiated with near-ultraviolet rays around the screen to prevent the screen from becoming soiled.
A black light or the like which imparts antifungal property and deodorant property may be provided.

[0045]

As described above, according to the reading apparatus of the first aspect, when the translucent photocatalytic film of the light receiving plate of the reading apparatus such as a copying machine or a scanner is irradiated with near-ultraviolet light in an interior light or natural light. , Electrons are emitted in the photocatalyst film to generate holes. For this reason, the conductivity increases, so that the amount of charge on the light receiving plate can be reduced and the generation of static electricity can be suppressed or prevented. For this reason, the light-receiving plate will have dust, cigarettes, hand grease,
It is possible to reduce or prevent organic substances such as mold and malodorous substances from being attracted and attached by static electricity.

Further, active electrons and holes of the photocatalyst film react with organic substances such as hand oil, mildew, and malodorous substances, or react with water to generate active OH radicals in the smoke attached to the light receiving plate. The generated OH radicals react with an organic substance to decompose and can be removed. That is, the photocatalytic film has antifouling property, antifungal property, and deodorant property. Moreover, since the photocatalyst film itself is harmless to the human body and has a light-transmitting property, it is possible to prevent the brightness of the light receiving plate from decreasing.

Therefore, according to the present invention, the dirt on the light receiving plate due to the adhesion of dust or organic matter is reduced or prevented,
Both the sharpness and cleanliness of the light receiving plate can be improved. As a result, maintenance for cleaning the light receiving plate can be reduced.

In the reading apparatus according to the second aspect, the method of forming the photocatalyst film includes a hydrolysis method of metal alkoxide, a sol-gel method, a chemical vapor deposition method, a vacuum vapor deposition method and the like.

According to the third aspect of the present invention, the photocatalyst film can be strongly adhered to the light receiving plate with an adhesive containing silicon dioxide as a main component, or the light receiving plate can be protected by the protective layer.

According to a fourth aspect of the invention, the photocatalyst film having substantially the same function and effect as the photocatalyst film of the first aspect of the reading device enables the light receiving plate of the OHP or the like to be antifouling, mildewproof and
Deodorant property can be imparted. For this reason, the definition and cleanliness of the light receiving plate can be improved, and the maintenance for cleaning the light receiving plate can be reduced.

In the projection device of claim 7, since the photocatalytic film can impart antifouling property, antifungal property and deodorant property to the projection surface of the screen, both the sharpness and the cleanliness of the screen can be improved. Therefore, the maintenance for cleaning the light receiving plate can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of a first embodiment of a reading device according to the invention.

2A is a vertical cross-sectional view of a main part when a photocatalytic film is formed on the outer surface of the light receiving plate shown in FIG. 1, and FIG. 2B is a case where the photocatalytic film is formed on both inner and outer surfaces of the light receiving plate shown in FIG. FIG.

3A and 3B are vertical cross-sectional views of respective main parts when an adhesive or a protective layer is interposed between the outer surface of the light receiving plate shown in FIG. 1 or both inner and outer surfaces and the photocatalyst film. .

FIG. 4 is a perspective view of a main part of the first embodiment of the projection device according to the present invention.

[Explanation of symbols]

 1 Copier (reading device) 2 Copier main body 3,13 Contact glass (light receiving plate) 5,14 Photocatalyst film 6 Adhesive or protective layer 11 OHP (projection device) 12 OHP main body

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display area H04N 1/00 B01D 53/36 1/10 H04N 1/10 1/107

Claims (7)

[Claims] 1. A reading device main body configured to place an original on an outer surface of a light receiving plate that receives light from a reading light source and to read the original; and at least one of an inner surface and an outer surface of the light receiving plate. A light-transmitting photocatalytic film formed thereon; 2. The reading device according to claim 1, wherein the photocatalytic film is formed as a thin film of at least one compound of titanium oxide, iron oxide, tungsten oxide, zinc oxide and strontium titanate. 3. The reader according to claim 1, wherein an adhesive or protective layer containing silicon dioxide as a main component is formed between the light receiving plate and the photocatalytic film. 4. A projection apparatus main body configured to mount an original on an outer surface of a light receiving plate for receiving light from a light emitting source and project the original on a screen; inside and outside of the light receiving plate. A projection device comprising: a light-transmitting photocatalytic film formed on at least one surface of both surfaces. 5. The image device according to claim 4, wherein the photocatalytic film is formed as a thin film by at least one compound of titanium oxide, iron oxide, tungsten oxide, zinc oxide and strontium titanate. 6. The projection device according to claim 4, wherein an adhesive or a protective layer containing silicon dioxide as a main component is formed between the light receiving plate and the photocatalytic film. 7. The projection device according to claim 4, wherein a photocatalytic film is formed on the image projection surface of the screen on which the image is projected.