KR20090105975A - Method for formation of photocatalytic layer - Google Patents

Abstract

To provide a various relevant techniques for full exploitation of the air cleaning effect which utilizes a photocatalyst such as titanium dioxide. [MEANS FOR SOLVING PROBLEMS] Platinum is used as the main catalyst and titanium dioxide, which is a photocatalytic substance, is used as an auxiliary catalyst to fully exploit the effect of adsorbing/decomposing an organic compound or the like of platinum and thereby produce an air cleaning effect at any time of day or night.

Description

Formation method of photocatalyst layer {METHOD FOR FORMATION OF PHOTOCATALYTIC LAYER}

The present invention relates to various related technologies for maximizing the air cleaning effect using a photocatalyst such as titanium dioxide, and more particularly, to the following techniques.

That is, the present invention intends to propose a novel method that makes it possible to remove harmful organic compounds and the like from day to night by using platinum as a main catalyst and photocatalyst as an auxiliary catalyst.

The present invention also relates to a photocatalyst article, and more particularly, to a photocatalyst article that can be easily applied to a surface of a substrate such as a glass window.

The present invention also relates to a method of forming a photocatalyst layer in which contaminants and harmful organic substances adhered on a substrate are excited and decomposed and removed by a photocatalyst composition by light such as ultraviolet rays.

The present invention also relates to a photocatalyst provided on a substrate such as a plastic plate or a glass plate, wherein the contaminants and harmful organic substances attached to the substrate are excited and excited by the photocatalyst composition by light such as ultraviolet rays.

Background Art A technique for removing harmful organic substances in the air using a photocatalyst material such as titanium dioxide and the surrounding related technologies have been proposed in the past.

That is, conventionally, the application of the photocatalyst to the indoor window is made by conventional methods such as dipping, spraying, spin coating, roll coating, doctor blade, and the like. A method for easily forming a photocatalyst film by coating and heating drying the photocatalyst paint or by a coating method using a binder (without calcination) is disclosed (for example, Japanese Patent Laid-Open No. 11-323188). ).

Moreover, conventionally, the method of decomposing | disassembling and removing using a photocatalyst composition is known as a method of removing the contaminant, harmful organic substance, etc. which adhered to the surface of a base material.

In this case, in order to decompose organic substances such as contaminants, it is necessary to irradiate light such as ultraviolet rays while the organic substances and the photocatalyst composition are in contact with each other. Therefore, the photocatalyst composition is not effective unless it is exposed to the outermost surface. . Therefore, conventionally, a surface coating agent containing a photocatalyst composition and a binder agent, and in some cases, a liquid photocatalyst containing an organic solvent or the like is directly applied onto a substrate, and then the binder and the like are wiped off to obtain the photocatalyst composition. The photocatalyst layer was formed by exposing to the surface (Japanese Patent Laid-Open No. 2004-230263).

Conventionally, the method of performing air purification which makes photocatalytic reaction the main means using titanium dioxide as a material has been devised.

In natural sunlight, there is a light source of 350-1500 mW / cm <2> in the vicinity of the inner side of a glass window on a favorable day. However, since it does not work at night, there is a drawback that the purification function cannot be performed by means of a photocatalytic reaction.

However, assisting with artificial light consumes energy and wastes resources.

In addition, the function of dropping NOx and other contaminants on the outer wall of a building, roads, etc. is difficult for a light source using a photocatalyst using titanium dioxide of the prior art.

In addition, in the prior art, since the photocatalyst is contained in the binder and the photocatalyst is not sufficiently coated on the surface of the binder so as to be exposed to the outermost surface, when the amount of the binder is large, the effect of the photocatalyst cannot be sufficiently exhibited, as a decrease in the removal rate of organic matter appears. There was this.

The present invention is to provide a photocatalyst article to eliminate the above problems.

In addition, in the prior art, when the surface coating agent is applied to a substrate having a large unevenness in comparison with the particle diameter of the photocatalyst composition on the surface of the substrate on which the photocatalytic layer is formed or the hole is formed, such as a net window, Since the photocatalyst composition and the binder agent are accumulated in the recesses and holes of the photocatalyst, the photocatalyst composition is not sufficiently exposed on the outermost surface, and thus there is a problem that organic substances such as contaminants cannot be sufficiently decomposed and removed.

The present invention has been made to solve the above problems, and even if the surface of the substrate has a large unevenness compared to the particle diameter of the photocatalyst composition or a hole is formed in the substrate, the photocatalyst composition is sufficiently exposed to the outermost surface to be fixed. It is an object of the present invention to provide a method for forming a photocatalyst layer.

In addition, a photocatalyst composition is a very small particulate matter having a diameter of about 6 to 10 nm, and when a binder or an organic solvent is mixed into a liquid so as to be applied onto a substrate, the particles of a plurality of photocatalyst compositions aggregate and form large particles. (Hereinafter referred to as 'secondary particles'), and these secondary particles are present locally on the substrate, so that the photocatalyst composition is not applied depending on the part on the substrate, so that organic substances such as contaminants, It could not be sufficiently decomposed and removed.

The present invention has been made to solve the above problems, and an object thereof is to provide a photocatalyst capable of uniformly dispersing particles of a photocatalyst composition on a substrate by suppressing formation of secondary particles.

The present invention has been made in order to solve such problems of the prior art, and a method of using platinum as a main catalyst has been conceived by changing the conventional way of thinking about a photocatalyst using titanium dioxide.

In other words, the problem can be solved by a method of compensating for the defects of the photocatalyst and sufficiently exhibiting the adsorption and decomposition functions of platinum.

Specifically, it is as follows.

(1) Based on the technical idea of using platinum as a main catalyst and titanium dioxide as a photocatalyst as a cocatalyst, a binder, platinum and titanium dioxide are mixed and applied to a substrate, and 0.05 to 50% of the content of titanium dioxide. Platinum adsorbs organic compounds at room temperature even when there is no light.Platinum adsorbs and decomposes organic compounds in air at the time of adsorption, and when left as it is, platinum is covered with decomposed substances in a few hours and becomes a catalyst poison. Since it does not decompose, during the day when sunlight shines, the photocatalyst oxidizes the material covered on the surface of platinum to remove the catalyst poison, and the platinum without catalyst poison restores the adsorption resolution and performs the photocatalytic reaction during the day. It is used in combination with titanium dioxide to exert an effect, and at night, it is adsorbed and decomposed into platinum, using platinum as the main catalyst in the air A method of removal by decomposing the organic compound.

(2) Platinum decomposes and adsorbs organic compounds in the air at night when there is no light, and during the day titanium dioxide undergoes a photocatalytic reaction using light of wavelength less than 390nm of sunlight, oxidizing the catalyst poison attached around the platinum. A method of decomposing and removing organic compounds in air by using the platinum according to (1) as a main catalyst, wherein the organic compounds can be decomposed and removed for 24 hours by removing them.

(3) Since it is a photocatalyst mainly composed of platinum, it is hereinafter referred to as a platinum-carrying superphotocatalyst. In order for the platinum-carrying superphotocatalyst to function, platinum and titanium dioxide must be in contact with the air, and also platinum particles and dioxide Since the particles of titanium must be properly stirred and mixed to support them, diatomaceous earth is formed in the form of fine powder of 20 nm to 100 nm as a binder so as to spread well during application, and vegetable oil, which is a binder auxiliary, can be used even if it is cold. Ethylene glycol is added as an antifreeze solution, and taurine and catechin are added as a diffusion material. The method according to (1) is used as a main catalyst to decompose and remove organic compounds in air.

(4) Apply the platinum-supported superphotocatalyst with a resin spatula, spreading the glass to about 5 to 100 nm as if it were cleaning the glass, and then wiping it with a towel-type cloth made of non-woven fabric. A method for decomposing and removing organic compounds in air by using the platinum according to (1) as a main catalyst, characterized by being in contact with air.

(5) Apply the amount of ultraviolet light sufficient to decompose and remove the organic compounds in the room to the inside of the glass window that can secure the most in the room, and apply 1/7 or more if the area required for the building is converted to the floor area. A method of decomposing and removing organic compounds in the air by using the platinum according to (1) as a main catalyst, characterized in that the area is about 0.08 square meters per square meter in terms of volume. .

(6) The coated glass becomes transparent, and the coated glass is applied by spreading it to a level of 5 to 100 nm as if the glass is cleaned using a resin applicator and then wiping it with a non-woven towel-type cloth. The platinum-supported superphotocatalyst applied on the basis of glass can be applied at 10 to 30 nm, so that the glass becomes transparent. The platinum as described in (1) is used as the main catalyst to decompose organic compounds in the air. How to get rid.

(7) When applying to tiles, concrete block materials, exterior walls, etc. used for buildings inside or outside buildings that are not required to be transparent, the binder is first applied as two kinds of liquids to be sprayed to attach a platinum-carrying superphotocatalyst in a semi-dry state. A method for decomposing and removing organic compounds in air by using the platinum according to (1) as a main catalyst, characterized by the above-mentioned.

(8) In the case of manufacturing a product by baking tiles or concrete block material, exterior wall material, etc. used inside or outside a building, if the temperature is 400 ° C. or less, the performance does not change even when baking the platinum-supported superphotocatalyst. A method of decomposing and removing organic compounds in air using the platinum described in the above) as a main catalyst.

(9) In order to promote the decomposition of nitrogen compounds, to promote the decomposition of NOx by adding a cerium oxide capable of redoxing nitrogen compounds to the platinum-supported superphotocatalyst by using heat of oxidation of titanium dioxide or heat of oxidation of platinum. A method of decomposing and removing organic compounds in air by using the platinum according to (1) as a main catalyst.

(10) Because of the platinum-supported superphotocatalyst, adsorption decomposition of organic compounds in the air is carried out on the platinum side, and redox of oxygen is carried out on the titanium dioxide side, thereby decomposing pollen which is the cause of sick house syndrome and pollen in the air. Decomposition and removal of organic compounds in the air by using the platinum according to (1) as a main catalyst, characterized in that the rate of decomposition of tick secretions that cause atopic dermatitis, atopic asthma and atopic rhinitis is accelerated. How to let.

(11) A method of decomposing and removing organic compounds in the air by using the platinum according to (1) as a main catalyst, characterized in that the platinum-supported superphotocatalyst is water repellent, making inorganic contaminants difficult to adhere.

(12) Also, the photocatalyst article of the present invention for achieving the above object is a photocatalyst article comprising a cleaning member, a photocatalyst surface coating member impregnated with a photocatalyst surface coating agent, and a wiping member, wherein the cleaning member is a glass window or the like. Cleaning the substrate surface, wherein the photocatalytic surface coating member is to clean the substrate surface with the cleaning member and then apply the photocatalyst surface coating agent to the substrate surface, and the wiping member is a surface of the photocatalyst surface. After the coating agent is applied, the surface of the substrate is wiped and finished.

(13) In the photocatalyst article of the present invention, in the photocatalyst article of (12), the cleaning member, the photocatalyst surface coating member, and the wiping member are each independently contained in an airtight packaging bag, and the photocatalyst surface coating member is placed therein. The sealed packaging bag may be formed of a light impermeable member.

(14) The photocatalyst article of the present invention is the photocatalyst article according to (12) or (13), wherein the substrate is glass, and the cleaning member, the photocatalyst surface coating member, and the wiping member are all made of ultra-fine chemical fibers. It may be to use.

(15) Furthermore, the means according to the present invention applies a photocatalyst base agent containing at least a binder agent and an organic solvent to a base material to form a photocatalyst base layer on the base material, and at least the photocatalyst composition and a dispersant in the photocatalyst base layer. It is a photocatalyst layer formation method which forms the photocatalyst layer on the said photocatalyst base layer by apply | coating the surface coating agent containing.

(16) In addition, in the invention according to (15), the binder according to the present invention may be a photocatalytic layer forming method containing any one of a modified epoxy resin or silicon oxide (SiO ₂ ).

(17) Furthermore, the means according to the present invention is a photocatalyst having a composition containing a dispersant in a photocatalyst comprising at least a photocatalyst composition, a binder agent, and a binder auxiliary agent containing an oil component.

(18) Moreover, the means which concerns on this invention is a binder adjuvant containing 0.1-20 mass% photocatalyst composition, 0.1-20 mass% binder agent, 20-70 mass% oil component, and 0.01-1 mass It is a photocatalyst of the structure containing a dispersing agent of%.

(19) Moreover, the means which concerns on this invention is a binder adjuvant containing 0.1-20 mass% photocatalyst composition, 0.1-20 mass% binder agent, 20-70 mass% oil component, and 0.1-1 mass It is a photocatalyst of the structure containing a polishing compound of% and 0.01-1 mass% dispersing agent.

(20) The means according to the present invention is the photocatalyst according to (17) to (19), and the dispersant may be a photocatalyst having a constitution containing an amino acid.

(21) The means according to the present invention is the photocatalyst according to (17) to (19), wherein the dispersant may be a photocatalyst having a structure containing sucrose fatty acid ester.

(22) The means according to the present invention is the photocatalyst according to (17) to (21), and the dispersant may be a photocatalyst having a constitution containing polyphenols.

Based on the technical concept of using platinum as the main catalyst, a binder, platinum and titanium dioxide are mixed and applied to a substrate, and platinum having 0.05 to 50% of the titanium dioxide content adsorbs organic compounds at room temperature even in the absence of light. At the time of adsorption, platinum decomposes organic compounds in the air, and if left as it is, platinum is covered with the decomposed material within several hours, so that adsorption is not decomposed. The catalyst poison is removed to remove the catalyst poison, and the platinum without catalyst poison is adsorbed and decomposed and used in combination with titanium dioxide, which performs photocatalytic reaction during the day, and at night, platinum is adsorbed and decomposed into platinum as the main catalyst. It is a method of decomposing and removing a compound, so it does not require light and removes harmful organic compounds in the air. The ability of the platinum day and night by combining the capacity and efficiency of the photo-catalytic material can be efficiently realize the air cleaning and the like.

In addition, in order for titanium dioxide to exhibit a photocatalytic effect, it is sufficient to have a light having a wavelength of 390 nm or less, so that the effect of the present invention can be maintained at all times for 24 hours by using ordinary sunlight that is sunk from the outdoors to the room.

Titanium dioxide, which is a photocatalyst, is loaded with platinum far exceeding the conventional level to form a platinum-carrying superphotocatalyst of the platinum principal, so that the air cleaning effect can be maintained for a long time even in the absence of light.

Using a spatula on the surface of a transparent glass window, etc., using a spatula, apply a thin layer of 5 to 100 nm, and wipe it with a cloth such as a non-woven fabric.Titanium dioxide carrying a sufficient amount of platinum is effectively in contact with the air for efficient air cleaning. The function can be realized.

The coating area is 1/7 or more in terms of the floor area, and 0.08 square meters or more per cubic meter in terms of volume, so that the air cleaning effect according to the present invention can be sufficiently exhibited. It was.

 It was found that the transparency of the transparent glass serving as the substrate was ensured by using the applied platinum-carrying superphotocatalyst to a thickness of 10 to 30 nm.

When applying to tiles, concrete block materials, exterior walls, etc. used for building materials that do not require transparency, a binder is first applied as two kinds of liquids to be sprayed, and a platinum-supported superphotocatalyst is attached in a semi-dry state. Depending on the characteristics, the most effective coating state can be realized.

When baking a tile or concrete block material or exterior wall material used inside or outside a building, the product is found to be unchanged even when baking platinum-supported superphotocatalyst if the temperature is below 400 ° C. Construction was realized.

In order to promote the decomposition of nitrogen compounds, it was found that by adding the heat of oxidation of titanium dioxide or the heat of oxidation of platinum, the addition of celium oxide capable of redoxing nitrogen compounds to the platinum-supported superphotocatalyst promotes the decomposition of NOx. The possibility of air purification for various materials has been shown.

Due to the platinum-carrying superphotocatalyst, adsorption decomposition of organic compounds in the air is carried out on the platinum side, and redox of oxygen is carried out on the titanium dioxide side, thereby decomposing pollen, which is the cause of sick house syndrome and pollen, in the air. Since the rate of decomposition of tick secretions that cause dermatitis, atopic asthma and atopic rhinitis increases, it is an effective invention for various symptoms.

Since the platinum-supported superphotocatalyst is water repellent, it is difficult to attach inorganic contaminants, so that the degradation of the surface due to contamination is less likely to occur.

According to the photocatalyst article of (12), the photocatalyst article is provided with a cleaning member, a photocatalyst surface coating member impregnated with a photocatalyst surface coating agent, and a wiping member, wherein the cleaning member cleans the surface of a substrate such as a glass window, The photocatalyst surface coating member is to apply the photocatalyst surface coating agent to the surface of the substrate after cleaning the surface of the substrate with the cleaning member, and the wiping member is a surface of the substrate after applying the photocatalyst surface coating agent to the surface of the substrate. In order to use the cleaning member → photocatalytic surface coating member → wiping member, the photocatalyst composition is fixed to the surface of the substrate such as a glass window in the exposed state, and finished with a wiping member to decompose the floating organic matter. The photocatalytic effect can clean the indoor air.

Further, according to the photocatalyst article described in (13) above, in addition to the effects of the invention described in (12) above, the cleaning member, the photocatalyst surface coating member, and the wiping member are each independently contained in an airtight packaging bag. The photocatalyst composition can be easily fixed by using a cleaning member → photocatalytic surface coating member → swapping member without using an applicator such as a spray on the surface of a substrate such as a glass window, and a seal containing the photocatalytic surface coating member therein. Since the container is formed of a light impermeable member, deterioration of the photocatalyst surface coating agent impregnated into the photocatalytic surface coating member can be prevented.

Further, according to the photocatalyst article described in the above (14), in addition to the effects of the invention described in the above (12) or (13), the cleaning member, the photocatalyst surface coating member and the wiping member are all made of a porous nonwoven fabric which is an ultrafine chemical fiber. Since it uses, it can prevent damaging the surface of the glass which is a base material.

Further, in the method for forming the photocatalyst layer according to the present invention, since the photocatalyst base layer is formed on the substrate and the photocatalyst layer is formed on the photocatalyst base layer, there are large irregularities on the surface of the substrate as compared with the particle diameter of the photocatalyst composition, or Even when the hole is formed, the photocatalyst composition can be exposed and fixed on the outermost surface, whereby the effect of the photocatalyst composition can be exerted.

Further, in the present invention, since the dispersant is contained in the liquid photocatalyst containing at least the photocatalyst, the binder, and the oil component and, if necessary, the binder adjuvant, the particles of the photocatalyst composition do not aggregate well. By suppressing the formation of secondary particles, it is possible to prevent the photocatalytic composition from locally present on the substrate and to evenly disperse the particles of the photocatalytic composition on the substrate.

In addition, since the photocatalyst contains amino acids, sucrose fatty acid esters, and polyphenols as the dispersant, it becomes possible to increase the particle dispersibility of the photocatalyst composition contained in the photocatalyst.

Hereinafter, the specific embodiment regarding the method of decomposing | disassembling and removing the organic compound in air using the platinum of this invention as a main catalyst is demonstrated.

First, the technical idea of decomposing and eliminating organic compounds and the like to exert an air cleaning effect as well as using platinum as a main catalyst and titanium dioxide as a photocatalyst as a secondary catalyst will be described. In case of purifying air by using photocatalytic material, various research and development has been made based on the idea of decomposing and removing organic compounds in air by using oxidation / reduction reaction by photocatalytic action. It is the start of the present invention to identify the cause for which the result cannot be easily obtained.

In other words, in order to achieve a more efficient air cleaning effect by the photocatalytic material, a thorough study has been made regarding the method of forming the photocatalyst layer, an article for realizing an effective coating state on the substrate, and a method of evenly dispersing the photocatalytic material particles by a dispersant. While development is underway, there have been situations in which the results of the theory have not been achieved.

In the process of finding the cause of such a situation, the inventors also use a photocatalytic material containing a very small amount of platinum as an auxiliary function for an auxiliary function, even if the light from the outside is blocked, such as at night, The focus is on the repetitive air cleaning effect. In other words, if the air cleaning effect is achieved only by the photocatalytic effect, the effect is not exerted when the light is blocked, but the effect persists for reasons other than the photocatalytic action, and this is explained.

Here, the inventors have noticed that the platinum contained in the trace amount as an auxiliary agent also has a redox effect as a catalyst. When the platinum functions as a catalyst, the surface is covered with decomposed substances, and the catalyst poison on the surface (which inhibits the catalyst function) The problem was that if the substance was not removed continuously, the harmful effects did not persist.

In order to overcome these difficulties, the inventor has repeatedly studied and continuously removes catalyst poisons on the surface of platinum by the decomposition and removal function of organic compounds using the redox effect of the photocatalyst material, regardless of the presence or absence of light rays. It is possible to continuously perform the air cleaning function for a long time regardless of the day and night.

That is, the inventors have completed the present invention by using platinum as a main catalyst having an air purifying function, and using a photocatalyst such as titanium dioxide to assist the catalyst poison on the surface of platinum.

Specifically, the use of platinum as the main catalyst means that a considerable amount of photocatalytic material is used to sufficiently decompose and remove the organic compounds, etc., of platinum, which was added in the prior art even though only a small amount was added. It is made to carry evenly on phosphorus titanium dioxide etc., and it shall be 0.05-50% with respect to content of titanium dioxide, More preferably, you may be 5-30%. That is, it does not occupy a main quantity as content, but it means that it not only functions as air purification but also plays a main role.

1 is applied to the platinum-supported photocatalyst according to the present invention in the glass window or wall of the laboratory in a state where new furniture is placed in a stretched room, and elapsed over 24 hours while measuring the formaldehyde concentration in the room every 30 minutes, It is a graph showing an example of the result when the action of the air purifying function according to the present invention is tested, and it is understood that formaldehyde concentration is suppressed low regardless of the day or night (in addition, the graph shows the result until 24 hours have elapsed). It is confirmed that the same effect can be obtained even after further experimentation.

The graph shows the conditions of concentration and humidity related to the amount of formaldehyde generated, and the change in the amount of ultraviolet light in the room related to the action of the photocatalytic material according to the change of measurement time. In other words, formaldehyde in the laboratory increases the temperature of the room, so that the amount of transpiration increases, so the amount of sunlight from the outside is small, and the amount of ultraviolet light from the outside is small. It occurs a lot during the rainy day. On the other hand, photocatalysts such as titanium dioxide are acting more on a sunny day when a large amount of sunlight is sunk down and the amount of ultraviolet rays is high.

 On the assumption that the above results are analyzed, it can be understood that the increase in the formaldehyde concentration in the laboratory during the morning is caused by the temperature increase in the laboratory. In addition, it can be understood that the formaldehyde concentration is suppressed below a certain value during the day when the amount of ultraviolet rays in the laboratory is abundant due to the air purification function by the photocatalytic material (although it is naturally affected by other conditions such as air temperature). In addition, it can be understood that the increase in formaldehyde concentration from evening to night is due to the fact that the photocatalytic effect is not achieved because the ultraviolet rays do not enter the room due to the absence of sunlight.

However, when interpreted only from the above premise, it is only natural that the formaldehyde concentration should be clearly increased at night (from 19:00 to early evening) when the amount of ultraviolet rays in the laboratory is significantly reduced, as can be seen from the experimental results shown in the graph. On the contrary, even in an environment in which the amount of ultraviolet rays is absolutely small, the formaldehyde concentration in the laboratory is kept low (although it is certain that there are other conditions such as room temperature).

Such a result is considered to be because the amount of platinum sufficient to purify the air in the laboratory is appropriately supported on a photocatalytic material such as titanium dioxide. In other words, since the air purification function using platinum as a catalyst is not limited by the amount of ultraviolet light in the room, it is considered to function effectively at night.

In addition, it is a photocatalytic substance that platinum, which is originally covered with a decomposition material such as an organic compound in the air and loses air purification function by a catalyst poison, continuously functions for several days beyond theoretical prediction. It is interpreted that the platinum supported in the proper state was able to exclude the decomposition material (catalyst poison) covering the surface by photocatalytic action.

That is, a photocatalyst such as titanium dioxide serves to remove the catalyst poison on the surface of platinum that is properly supported by photocatalysis using ultraviolet rays. For example, the surface is covered with a catalytic poison by an adsorption action at night and the like, so that the platinum, which has an air purifying function, is also cleaned by the photocatalysis during the following day, and as a result, the next night It is possible to return to a state in which the air purification function can be performed again.

That is, from the results shown in FIG. 1, when the platinum-supported photocatalyst of the present invention is effectively utilized, the main catalyst may be used not only in the presence of abundant ultraviolet rays due to sunlight or the like, but also in a time zone where the photocatalysis does not work, such as at night. The air purifying function is continued by the catalytic action of platinum supported on photocatalytic materials such as titanium dioxide, and the catalyst poisons covering the surface of platinum are properly removed by the photocatalytic reaction during the day. The air purifying function will be described.

In addition, in the case of various pollen, which is the cause of allergic pollen allergy such as cedar pollen, there was a situation in which a conventional photocatalytic material could not be expected to sufficiently decompose and remove, but as a main catalyst functioning as an air purifying function as in the present invention When sufficient amount of platinum was loaded (for example, about 10%), it was confirmed that various pollen was completely decomposed and removed in only a few hours.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of the photocatalyst article of this invention is described based on drawing.

The base material (not shown) to which the photocatalyst article A is apply | coated is glass (for example, glass window), synthetic resin, etc. When the photocatalyst composition is fixed to the surface of the substrate, and ultraviolet rays are irradiated from the back surface of the substrate (for example, when the sunlight enters through the glass window), a synthetic resin that transmits ultraviolet rays is used, and the ultraviolet rays are irradiated from the surface of the substrate. In this case, it is not necessary to use a material that transmits ultraviolet rays.

The photocatalyst article (A) is impregnated with a porous nonwoven fabric cleaning member (4) penetrated with a contaminant remover to clean the surface of the substrate, and a photocatalyst surface coating agent (a mixture of an abrasive, a catalyst composition, a binder, and a binder aid). The photocatalyst surface coating member 5 (the photocatalytic surface coating member 5 is a porous nonwoven fabric, for example), and a wiping member 6 for wiping the surface of the substrate after applying the photocatalyst surface coating agent to the substrate surface. (The wiping member 6 wipes the binder aid, for example.), And as shown in FIG. 2, each of the airtight packaging bags 2 having the adhesive opening / closing portions 1, 1 ', and 1 " 2 ', 2 "). In addition, the photocatalyst article A is accommodated in the box not shown.

The sealed packaging bag 2 including the cleaning member 4 therein is sealed by a crimped portion 9 which is pressed at both ends, and the sealed packaging bag 2 'including the photocatalyst surface coating member 5 therein. ) Is hermetically sealed by a crimping portion 9 ', which is compressed at both ends, and a hermetic packaging bag 2 " containing a wiping member 6 therein by a crimping portion 9 " It is sealed.

And, as will be described later, the photocatalyst composition is exposed to the outermost surface on the surface of a substrate (not shown) such as a glass window in the room in the order of use of the cleaning member 4 → photocatalytic surface coating member 5 → wiping member 6. The photocatalyst composition is fixed, the binder aid is wiped off as a finishing means, and the floating organic matter is decomposed to clean the air in the room.

The cleaning member 4 includes a contaminant remover (for example, ethyl alcohol or a surfactant, tocopherol, ion exchanged water, L-ascorbic acid, citric acid, etc.) to clean the surface of the substrate (not shown). Liquid detergent) is impregnated (penetrated) with the porous nonwoven fabric.

Before applying the photocatalyst surface coating agent to the cleaning member 4 of the porous non-woven fabric for cleaning the surface of the substrate impregnated with the contaminant remover, for example, a contaminant on the surface of the substrate (coated surface) such as a glass window in the room, in particular a glass surface. Remove oil.

The photocatalyst surface coating member 5 is obtained by impregnating (penetrating) a porous nonwoven fabric with a mixture of an abrasive, a photocatalyst composition, a binder, and a binder aid.

In addition, the above-mentioned cleaning member 4 or photocatalyst surface coating member 5 can be provided by immersing in the contaminant removal agent or photocatalyst surface coating agent of each porous nonwoven fabric, respectively.

The member 6 for wiping the porous nonwoven fabric for wiping the binder aid is used as it is without impregnation (penetration) of the member 4 for cleaning and the photocatalyst composition member 5 described above.

In addition, as a finishing means, moisten a towel or a towel (preferably water of about 40 ° C. or moisten water to 1/3 part of the lengthwise direction of the towel, and dry the remaining 2/3 part lengthwise part of the towel). The moistened portion is sandwiched between and wiped so that the binder aid does not remain on the surface of the substrate by a finishing means (not shown) such as the dry portion of the outer surface of both sides.

The cleaning member 4, the photocatalyst surface coating member 5, and the wiping member 6 are all made of ultrafine chemical fibers, and because of the ultrafine chemical fibers, it is possible to prevent the surface of glass or the like from being damaged.

The sealed packaging bag 2 includes a plurality of cleaning members 4 in a sealed state, and its appearance is shown in FIGS. 2 and 3. Then, the cleaning member 4 appropriately makes a fold line on the porous nonwoven fabric, forms a boundary appropriately, and folds it, and wraps it in the closed packaging bag 2.

1 is an adhesive opening / closing part for opening / closing the outlet 21, and a re-peelable adhesive is coated around the outlet 21 corresponding to the back surface of the adhesive opening / closing part 2 or the back side of the adhesive opening / closing part 1. 21) can be sealed by repeating the lid. By sealing, the cleaning member 4 in the airtight packaging bag 2 can be prevented from being contaminated by mold / microorganisms (see FIGS. 2, 3, 6, and 7).

The sealed packaging bag 2 'is to include the plurality of photocatalyst surface coating members 5 in a sealed state, and their appearance is shown in FIGS. 2 and 4. Then, the photocatalyst surface coating member 5 appropriately creates a fold line on the porous nonwoven fabric, forms a boundary appropriately, and folds it to be included in the sealed packaging bag 2 '.

1 'is an adhesive opening / closing part for opening and closing the outlet 21', and a re-peelable adhesive is applied around the back of the adhesive opening and closing part 1 'or around the outlet 21' corresponding to the back of the adhesive opening and closing part 1 '. It can be sealed by repeating | covering the outlet 21 'repeatedly. By sealing, the photocatalyst composition 5 in the sealed packaging bag 2 'can be prevented from being contaminated by mold and various bacteria. In particular, the closed packaging bag 2 'for packaging the photocatalyst composition member is formed of a light impermeable member (for example, an aluminum deposition sheet).

The photocatalyst composition of the photocatalyst surface coating agent impregnated (penetrated) to the photocatalyst surface coating member 5 is titanium oxide, titanium dioxide, or a sol-gel titanium compound, or zinc oxide, tin oxide, iron oxide, copper oxide, silver oxide, tungsten oxide, or zirconium oxide. , Metal oxides such as bismuth oxide, indium oxide, cadmium oxide, germanium oxide, nickel oxide, cobalt oxide, chromium oxide, manganese oxide, vanadium oxide, niobium oxide, antimony oxide, strontium titanate, and the like. Anatase type titanium dioxide crystals, rutile type titanium dioxide crystals or mixtures thereof, or sol-gel type titanium compounds are preferable. In addition, the photocatalyst by the photocatalyst surface coating member 5 can also use a photocatalyst effect in visible region.

The photocatalyst composition of the photocatalyst surface coating agent impregnated (impregnated) in the photocatalyst surface coating member 5 is not limited to the above-described one, and the photocatalyst particles have at least one metal or metal compound on the surface of the photocatalyst particles physically or chemically. It may be immobilized at (see Japanese Patent Laid-Open No. 2000-96800). For example, gold, silver, copper, platinum, iron, cobalt, nickel, chromium, zinc and the like, platinum is most preferred. By supporting the metal on the surface of the photocatalyst, charge separation of the photocatalyst is promoted and the photocatalyst characteristic becomes larger. A photocatalyst composition is used even when a metal is supported on the surface of the photocatalyst or a photocatalyst is supported on the surface of the metal. The immobilization amount of the metal is preferably 1% by weight to 50% by weight based on the total amount of the photocatalyst composition.

Further, 0.1 wt% to 30 wt% of the photocatalyst is added to an organic solvent such as ethanol, and stirred sufficiently to form a sol-gel, followed by addition of a metal having a larger photocatalytic property, followed by stirring. Alternatively, the photocatalyst may be mixed with a metal having a larger photocatalytic property, mixed with an organic solvent such as ethanol, and stirred sufficiently to form a sol gel.

In addition, the particle size of titanium dioxide is not particularly limited, but may be 6 nm to 10 nm in particle diameter that is easily dissolved in an organic solvent. It is preferable that the density | concentration of the photocatalyst composition contained in the solution of the organic solvent containing a photocatalyst composition shall be 0.1 to 80 weight%. If the concentration of the photocatalyst composition is less than 0.1% by weight, the effect by the photocatalyst, i.e., the decomposition of contaminants, becomes weak, which is not preferable.

In addition, the ultrafine particle solution of the photocatalyst composition is a solution containing 30 to 60% of organic solvents such as ethyl alcohol, isopropylene alcohol, and butyl alcohol and 1% or less of sulfuric acid / nitric acid, and 1 to 30 of anatase or rutile titanium alkoxide crystals. It is an acid suspension containing titanium dioxide mixed and adjusted to%.

Further, the photocatalyst composition of the photocatalyst surface coating agent impregnated (penetrated) to the photocatalyst surface coating member 5 is formed in the fine powder, and its particle diameter is 6 nm to 10 nm, and is 0.1% by weight to 30% based on the total amount of the photocatalyst surface coating agent. % By weight. If it is 10 nm or more, it will be difficult to melt | dissolve into the binder solution mentioned later, and the surface of the base material after application | coating will become cloudy, and the problem that transparency falls large will arise.

The photocatalyst surface coating agent is composed of a photocatalyst composition, a binder agent, a binder aid, and an abrasive.

In addition, in the above-mentioned compounding ratio of the photocatalyst composition, if less than 0.1% by weight, the harmful substance (organic compound) is not reduced oxidation and thus can not exhibit sufficient photocatalytic action, and if it is 30% by weight or more, transparency of the substrate surface cannot be obtained. Cause problems.

In addition, the photocatalyst composition is hardly oxidized by adjusting the pH (unit indicating whether it is acidic or alkaline) to a value of 1 to 6 by adding a conventional surfactant and maintaining it in acidic or weakly acidic properties. The deterioration of the added oil component can be avoided. At this time, when the pH value is adjusted to less than 1, the acid is too strong to degrade the oily component, and when adjusted to 6 or more, the quality of the oily component cannot be maintained.

The above-mentioned binder acts as a binder for supporting the photocatalyst composition. For example, a suitable composition such as a silicone resin, an acrylic resin, a fluorine resin, an epoxy resin, or a natural grass is used, and a diluent such as water or ethyl alcohol is used. As a result, it is formed in the form of a solution having a predetermined concentration, which improves fluidity. The blending ratio is, for example, adjusted to 0.1% by weight to 20% by weight relative to the total amount of the photocatalyst surface coating agent. When diluting, the mixture of the diluent: binder liquid is 70% by weight to 99.9% by weight: 30% by weight. It is preferable to set it as the compounding quantity of about -0.1 weight%. The binder adjuvant is for applying the photocatalyst composition as thinly as possible onto the surface (application object) of the substrate.

This binder adjuvant has an oil component, and this oil component consists of a conventional surfactant, for example, a wax derived from a natural product, a mineral spirit type solvent, vegetable oil, etc. Among the oil components, waxes derived from natural products include, for example, canuba wax, candelilla wax, rice bran wax, melon wax, sugar cane wax, jojoba wax, flux seed wax, waxy wax, lacquer wax, beeswax and the like. It is enough to select one of these groups. These oil components exhibit water repellency and have a property of being compatible with synthetic resin due to gloss on the coated surface.

In addition, it shows good coating properties, has good alkali resistance, weather resistance, and quick drying property, and at the same time, the coating work by the coating method used in normal maintenance such as spray, brush, roller, etc. is good, and the mineral spirit solvent having low toxicity is also used. It is used as a component of a binder adjuvant. Examples of the mineral spirits in the above-described binder adjuvant include mineral tapene, white spirit, mineral thinner, petroleum spirit, and the like, and at least one kind may be selected from this group. Moreover, the vegetable oil in the said binder auxiliary has the property of an undried oil, and the vegetable oil which does not oxidize and deteriorate well is preferable. In other words, any material that plays a role of thinly spreading can be selected, for example, camellia oil, olive oil, sesame oil, soybean oil, sunflower oil, rapeseed oil, or evening primrose oil, and at least one type is selected from this group. Just do it.

In addition, an antioxidant may be added to this photocatalyst surface coating agent as needed in order to prevent the discoloration resulting from oxidation of the said vegetable oil or waxes, For example, hydroxyl toluene, tocopherol, phytic acid (phytic acid) is used. In addition, phenolic substances, aromatic amines, phenothiadines, dithiophosphates, dithiocarbamates, sulfides, olefin sulfides and the like can also be used. In addition, L-ascorbic acid fatty acid ester, L-ascorbic acid palmitic acid ester and / or L-ascorbic acid stearic acid ester, etc. are effective for antioxidant of vegetable oil.

In addition, as antioxidants of food additives, L-ascorbic acid, L-ascorbic acid sodium (vitamin C), ethylenediamine tetraacetic acid Ca2Na, ethylenediamine tetraacetic acid 2Na, ersosorbic acid, sodium sorbate, guac resin (guaiac resin) ), Isopropyl citrate, nordihydroguanyretic acid, molar asset propyl, dibutylhydroxytoluene (BHT), d1-α-tocopherol (vitamin E), butylhydroxyanisole (BHA), rosemary extract, ethoxylated As a preservative of food additives, benzoic acid, sodium benzoate, sorbic acid, potassium sorbate, sodium dihydroacetate, isobutyl paraoxybenzoate, isopropyl paraoxybenzoate, ethyl paraoxycin benzoate, butyl paraoxine benzoate, paraoxine benzoate Propyl, propioic acid, sodium propioate, calcium propioate and the like can be used. You may add at least 1 type of these antioxidant.

Next, the method for applying the photocatalytic surface coating agent to the substrate surface and the photocatalyst surface coating agent according to the present invention will be described.

The ultracatalyst solution of the photocatalyst composition, a binder agent, a binder adjuvant containing an oil component, and an abrasive are mixed to obtain a liquid photocatalyst surface coating agent, and the photocatalytic surface coating member 5 impregnated (penetrated) with the photocatalyst surface coating agent. The photocatalyst layer is formed on the surface of the substrate by spreading it thinly on the surface of the substrate, and the layer of the photocatalyst composition and the binder assistant is removed by the wiping member 6 together with the abrasive included in the layer of the binder and the binder assistant. The photocatalyst composition is then exposed on the surface of the outermost layer of the photocatalyst layer so as to leave no binder auxiliary.

Since the abrasive is formed of 0.1 micron to 0.5 micron particles of a material such as silica or ceramic, it is added to the photocatalyst surface coating agent and mixed.

If the particles of the abrasive are less than 0.1 micron, the photocatalyst composition and the binder agent are wiped together and removed when wiping the photocatalyst layer. If the particles are 0.5 microns or more, the entire photocatalyst layer is removed by the abrasive. .

In the case of mixing the abrasive, it may be added after addition to a binder, a binder aid, or the like, and the blending ratio is 10% by weight to 50% by weight.

If the added amount of the abrasive is less than 10% by weight, the solidification proceeds before the photocatalytic surface coating agent is applied to the substrate surface, causing problems in the coating process, and if it is 50% by weight or more, it is too water-soluble to the photocatalytic surface coating member 5. Difficult to apply.

In addition, the photocatalyst composition, the binder agent, the binder auxiliary agent, and the abrasive agent can be added together, for example, in a suitable container, and diluted and diluted to a predetermined concentration with a dilution solution such as ethyl alcohol or water. It can select arbitrarily within the compounding range shown in the form.

As an example of a photocatalyst surface coating agent, the following are mentioned.

One compounding example of a photocatalyst surface coating agent (It is a matter of course that it is not limited to this compounding ratio.)

Photocatalyst composition … … 5 wt%

· Binder system … … 5 wt%

· Binder aids… … … 65% by weight

· Polishing agent… … … 25% by weight

Were added and mixed with stirring to obtain a liquid photocatalyst surface coating agent.

The photocatalyst article A was taken out of the packaging box (or packaging bag) which is not shown in figure (the taken out state is shown in FIG. 2). The sealing opening and closing part 1 is peeled off, and the cleaning member 4 is taken out from the outlet 21, and the sealing opening and closing part 1 'is peeled off, and the photocatalyst surface coating member 5 is removed from the outlet 21', and the sealing opening and closing part 1 "is opened. Peel off and remove each member 6 for wiping from the outlet 21 ".

Photocatalyst composition with a photocatalytic surface coating member (5) in which a cleaning member (4) penetrates a contaminant remover, for example, cleans the substrate surface of an indoor glass window, and penetrates a mixture of an abrasive, a catalyst composition, and a binder and a binder aid. Is fixed to the substrate surface of the indoor glass window in an exposed state, and the binder 6 and the finishing means for wiping out unnecessary binder aids to fix the photocatalyst composition to the outermost surface surface are removed on the substrate surface such as the indoor glass window. The photocatalyst composition is fixed. In a series of operations, the photocatalyst composition is applied transparently to the surface of the interior glass window. The state in which the photocatalyst composition is applied can be confirmed by a gritty feel only by lightly touching the glass window of the room with a fingertip.

In addition, although the said photocatalyst article is not necessarily related to a platinum carrying photocatalyst, it is clear that it is useful when actually using a platinum carrying photocatalyst.

An embodiment of the method for forming a photocatalyst layer of the present invention will be described with reference to FIG. 8.

In the figure, 1 is a base material, 2 is a photocatalyst base agent applied on the base material 1, and 3 is a surface coating agent applied on the photocatalyst base agent 2.

The substrate 1 serves as an object for decomposing and removing organic substances such as contaminants, and serves as a carrier for forming the photocatalyst composition 31 described later. As this base material 1, a nonwoven fabric, a window screen, a roll curtain, an air conditioner filter, a resin board, the exterior wall material of a building, a tent, a concrete block, etc. are mentioned, for example.

The photocatalyst base agent 2 includes a binder agent 21 for fixing the photocatalyst composition 31. The binder agent 21 and the organic solvent 22 are mixed at a predetermined ratio, for example, a binder agent ( 21) of 0.1% by mass to 10% by mass of silicon oxide (SiO ₂ ) mixed with an organic solvent 22 such as ethanol to form a liquid, or as a binder 21, 0.1% by mass to 10% by mass of modified The epoxy resin mixed with an organic solvent 22 containing butyl acetate, cyclohexane, propylene glycol monomethyl ether, propylene glycol methyl ether acetate and the like is used as a liquid. In addition, in order to disperse | distribute the binder agent 21 further, the photocatalyst base agent 2 may mix the dispersing agent 32 mentioned later.

The surface coating agent 3 includes a photocatalyst composition 31 which decomposes organic substances such as contaminants. The surface coating agent 3 comprises 0.1 mass% to 20 mass% of the photocatalyst composition 31 and 0.01 mass% to 1 mass% of the dispersant 32. Mixed with an organic solvent 33 such as ethanol to make a liquid.

The photocatalyst composition 3 described above is formed as a particle, and is composed of titanium oxide, titanium dioxide, or a sol-gel titanium compound, or zinc oxide, tin oxide, iron oxide, copper oxide, silver oxide, tungsten oxide, zirconium oxide, bismuth oxide, indium oxide. , Metal oxide compounds such as cadmium oxide, germanium oxide, nickel oxide, cobalt oxide, chromium oxide, manganese oxide, vanadium oxide, niobium oxide, antimony oxide, strontium titanate, and the like, and titanium dioxide is preferable, and anatase type dioxide Titanium crystals, rutile titanium dioxide crystals or mixtures thereof, or sol-gel titanium compounds are preferred. Although the particle diameter of this photocatalyst composition 31 is not specifically limited, The particle diameter of 6 nm-10 nm of the grade which is easy to melt | dissolve in the organic solvent 33 may be sufficient. If the particle size is less than 6nm, it is difficult to process and the cost rises, and if the particle size is 10nm or more, not only it is difficult to dissolve in the organic solvent 33, but also the surface of the base material 1 after the application is white and transparent. This is because it is greatly reduced.

The dispersant 32 described above disperses particles such as the photocatalyst composition 31, for example, amino acids such as theanine, lysine, glutamic acid, aspartic acid, arginine, proline, sucrose stepanic acid ester, sucrose stearic acid ester, sucrose Polyphenols such as sucrose fatty acid esters such as palmitic acid esters and catechins are used. Natural products may be used, for example, by extracting tea leaves containing catechin of polyphenols or theanine of amino acids in the components with hot water. The extract obtained etc. can also be used.

Although not shown, the surface coating agent 3 may be mixed with metals or metal compounds such as gold, silver, copper, platinum, iron, cobalt, nickel, chromium and zinc, for example. The mixing of the metal or the metal compound promotes charge separation by the photocatalyst composition 31, so as to further improve the decomposition characteristics of the organic material by the photocatalyst.

In addition, although not shown in figure, you may mix cerium oxide with the surface coating agent (3). Cerium oxide is used to decompose and remove organic substances such as contaminants by heat, and effectively use the heat of reaction (heating) accompanying the decomposition of organic substances generated by the decomposition elimination action of the photocatalyst composition 31 to enhance the effect of decomposition and removal. For sake.

Next, a method of forming the photocatalyst layer 30 will be described. First, as shown in Fig. 8 (a), the photocatalyst base agent 2 is applied onto the base material 1 using a known technique such as a coating method using an application spatula to form the photocatalyst base layer 20. The thickness of the photocatalyst backing layer 20 may be such that the photocatalyst composition 31 and the metal or metal compound can be fixed. For example, the photocatalyst base layer 20 is formed to have a thickness of about 10 nm after drying.

After the application of the photocatalyst base agent 2, the organic solvent 22 gradually evaporates, and on the photocatalytic base layer 20, the application spatula is estimated just before drying the photocatalyst base agent 2 in a less dry state. The surface coating agent 3 is apply | coated using well-known technique like the apply | coating method using (refer FIG. 8 (b)). Then, by evaporating and drying the remaining organic solvent 22 and the organic solvent 33 in the coated surface coating agent 3, the photocatalyst composition 31 can be fixed on the photocatalyst base layer 20.

In addition, the above-mentioned drying may be either the natural drying which is left to dry at room temperature, or the forced drying which dries by drying with warm air.

However, the application of the surface coating agent 3 while the photocatalyst base agent 2 is less dry is to fix the photocatalyst composition 31 to the upper portion of the photocatalyst base layer 20 by the binder agent 21, and the photocatalyst After the organic solvent 22 in the base agent 2 or the organic solvent 33 in the surface coating agent 3 is evaporated and dried, the photocatalyst composition 31 is exposed to the outermost surface as shown in Fig. 8C. You can.

Further, the modified epoxy resin is used as the binder 21 of the photocatalyst base agent 2 in order to firmly adhere particles such as the photocatalyst composition 31 even if the unevenness of the surface of the base material 1 is relatively small. The use of silicon oxide (SiO ₂ ) as the binder agent 21 is to prevent particles such as the photocatalytic composition 31 from settling and buried in the photocatalyst base layer 20 before the organic solvent 22 is completely dried. to be. In addition, what is necessary is just to select the kind of photocatalyst base agent 2 to be used suitably according to the surface state of the base material 1, etc.

In addition, the mixing of the dispersant 32 with the surface coating agent 3 is to prevent agglomeration of particles such as the photocatalyst composition 31, and since the particles do not settle before application, there is no need to stir immediately before application. After application, the photocatalyst layer 30 may be formed by preventing localization due to aggregation of particles and uniformly fixing the photocatalyst on the photocatalyst backing layer 20.

Therefore, since the surface coating agent 3 does not include the binder 21 for fixing the photocatalyst composition 31 as in the prior art, when the organic solvent 33 is completely dried, the surface coating agent 3 is not wiped off after application of the surface coating agent 3. If not, the photocatalyst composition 31 may be exposed on the outermost surface, and the dispersant may be mixed to uniformly fix the photocatalyst on the photocatalyst backing layer 20, resulting in poor surface flatness and large unevenness. Even in the case of a substrate having holes formed therein, the photocatalyst composition 31 may be exposed on the outermost surface of the substrate to form the photocatalyst layer 30. Therefore, when organic substances, such as contaminants, adhere to the surface, the photocatalyst composition 31 contacts the photocatalyst composition 31. When light such as ultraviolet rays is irradiated in this state, organic substances such as contaminants are decomposed by excitation of the photocatalyst composition 31. And removed.

In addition, the formation method of the photocatalyst layer here does not necessarily relate to a platinum-supported photocatalyst, but it is naturally applicable even when a platinum-supported photocatalyst is actually used.

In addition, an embodiment of the photocatalyst of the present invention will be described below with reference to FIGS. 9 to 10.

In Fig. 9A, A 'is a photocatalyst, and is applied onto a base material 1 such as a glass window of a building or a car, a plastic plate or a solar part, an interior wall surface, and the like by irradiation with light such as ultraviolet rays. Due to the photocatalytic action of the photocatalyst composition 11a contained therein, contaminants and harmful organic substances attached to the substrate 1a are decomposed and removed.

The photocatalyst A 'is composed of an organic solvent such as ethanol or the like at a predetermined ratio of the photocatalyst composition 11a, the dispersant 12a, the binder agent 14a, and the binder auxiliary agent 15a containing the oil component. It is mixed with 13a) and adjusted to the liquid phase.

The photocatalyst composition 11a is a particulate matter, titanium oxide, titanium dioxide, or sol-gel titanium compound, or zinc oxide, tin oxide, silver oxide, tungsten oxide, zirconium oxide, bismuth oxide, indium oxide, cadmium oxide, oxide oxide. Examples include metal oxides such as germanium, nickel oxide, cobalt oxide, chromium oxide, manganese oxide, vanadium oxide, niobium oxide, antimony oxide, and strontium titanate, with titanium dioxide being preferred, anatase titanium dioxide crystals, rutile dioxide Titanium crystals or mixtures thereof or sol-gel type titanium compounds are preferable. Although the particle diameter of this photocatalyst composition 11a is not specifically limited, The particle diameter of 6 nm-10 nm of the grade which is easy to melt | dissolve in the organic solvent 13a may be sufficient. If the particle diameter is less than 6nm, it causes a problem that processing is difficult and the cost is increased. If the particle diameter is more than 10nm, it is difficult to melt in the organic solvent 13a, and at the same time, the surface of the substrate 1a is whitened after application. This is because transparency is greatly reduced. In addition, it is preferable that the compounding ratio of the photocatalyst composition 11a shall be 0.1 mass%-20 mass% with respect to the whole amount of a photocatalyst (A '). This is because if it is less than 0.1% by mass, organic matters such as contaminants are not decomposed and sufficient photocatalysis cannot be exerted. If it exceeds 20% by mass, transparency of the surface of the substrate 1a cannot be obtained.

The dispersant 12a described above disperses particles such as the photocatalyst composition 11a, and for example, amino acids such as theanine, lysine, glutamic acid, aspartic acid, arginine, and proline, sucrose stearic acid ester, sucrose stearic acid ester, and sucrose. Polyphenols such as sucrose fatty acid esters such as palmitic acid esters and catechins may be used. Natural products may be used. For example, tea leaves containing polyphenols such as catechin or amino acid theanine in the component may be extracted with hot water. You may use the extract liquid etc. which are obtained. Moreover, it is preferable to make the compounding ratio of the dispersing agent 12a into 0.01 mass%-1 mass% with respect to the whole amount of a photocatalyst (A '). It is because a dispersion effect will not be acquired when it is less than 0.01 mass%, and when it exceeds 1 mass%, fluidity will fall and coating will become difficult.

The binder 14a described above fixes the photocatalyst composition 11a on the substrate 1a. For example, a suitable composition such as silicone resin, acrylic resin, fluorine resin, epoxy resin, natural grass, or the like is used. The mixture is mixed with the photocatalyst so as to have a predetermined concentration. In addition, it is preferable that the mixing ratio of the binder agent 14a shall be 0.1 mass%-20 mass% with respect to the whole amount of a photocatalyst (A '). This is because when the amount is less than 0.1% by mass, the particles of the photocatalyst composition 11a cannot be sufficiently adhered to the substrate, and when the amount exceeds 20% by mass, the fluidity of the solution is lowered and it is difficult to apply.

The binder adjuvant 15a mentioned above is for apply | coating the photocatalyst composition 11a as thinly as possible to the surface (application object) of the base material 1a. This binder adjuvant 15 has an oil component, and this oil component is comprised, for example in the liquid phase from the wax derived from a natural product, a mineral spirit type solvent, vegetable oil, etc., and conventional surfactant, water, or ethanol. Among the oil components, waxes derived from natural products include, for example, canuba wax, candelilla wax, rice bran wax, melon wax, sugar cane wax, jojoba wax, flux seed wax, beeswax, lacquer wax, beeswax and the like. Just select one of the groups. It is preferable that these oil components exhibit water repellency and produce gloss on the coated surface, so that the oil content is 20% by mass to 70% by mass based on the total amount. This is because if it is less than 20% by mass, a mass of rice grains containing particles such as the photocatalyst composition 11a is produced, and if it is more than 70% by mass, the entire photocatalyst A 'is hardened and cannot be applied.

By the way, although not shown in figure, metal or metal compounds, such as gold, silver, copper, platinum, iron, cobalt, nickel, chromium, zinc, may be mixed with the photocatalyst A ', for example. This is because the charge separation by the photocatalyst composition 11a is promoted by mixing this metal or a metal compound, and the decomposition property of organic substance etc. by a photocatalyst is improved more.

In addition, although not shown, you may mix cerium oxide with the photocatalyst A '. Cerium oxide is used to decompose and remove organic substances such as contaminants by heat, and effectively use the heat of reaction (heating) accompanying the decomposition of organic substances generated by the decomposition elimination action of the photocatalyst composition 11a to enhance the effect of decomposition and removal. For sake.

As shown in Fig. 10A, the abrasive 16a may be mixed with the photocatalyst A 'described above. The abrasive 16a is applied to the photocatalyst A 'on the substrate 1a and then wiped so that the photocatalyst composition 11a can be exposed from the outermost surface as shown in Fig. 10 (b). When wiping by (2a), the excess binder agent 14a and the like are wiped off.

This abrasive 16a is formed in the form of particles having a particle diameter of 30 nm to 500 nm by a material such as silica or ceramic, and is mixed and adjusted to the photocatalyst A '. This causes a problem that when the particle size of the abrasive 16a is less than 30 nm, the photocatalyst composition 11a and the binder agent 14a are wiped together and removed when wiping the coating layer 3a. This is because the photocatalyst A 'remains thick even after being taken out, resulting in a problem that the ratio of the photocatalyst composition 11a exposed to the outermost surface becomes small. In addition, it is preferable that the compounding ratio of the abrasive | polishing agent 16a shall be 0.1 mass%-50 mass% with respect to the whole amount of a photocatalyst (A '). If it is less than 0.1% by mass, the oil component remains, so that it is not sufficiently wiped. If it is more than 50% by mass, the photocatalyst composition 11a and the binder agent 14a remaining on the substrate 1a are reduced. Because.

Next, the formation method on the base material 1a using the photocatalyst A 'is demonstrated.

For the substrate 1a to be coated with the photocatalyst A ', the contaminants on the surface (coating surface) of the substrate 1a, in particular, the oil component adhering to the surface, may be removed. As a component, a liquid detergent containing ethyl alcohol, a surfactant, tocopherol, ion-exchanged water, L-ascorbic acid, citric acid, etc.) is sparged and thoroughly removed by a rag or the like.

9A and 10B, the adjusted photocatalyst A is evenly applied by a well-known technique such as application using the entire surface of the substrate 1a or an application spatula, and the substrate 1a. The application layer 3a is formed on the surface of the ().

Subsequently, with respect to the application layer 3a of the photocatalyst A 'applied to the surface of the base material 1a in a state where the application layer 3a is not dried (a state in which the wet state still remains), As shown in FIG. 9 (b) and FIG. 10 (b), the wiping means 2a wipes with a cloth such as bulky fibers, for example, to apply the coating layer 3a in the photocatalyst A '. Particles of the photocatalyst composition 11a, the binder agent 14a and the binder aid 15a are removed, and the photocatalyst layer 4a is formed to expose the photocatalyst composition 11a on the outermost surface portion of the surface layer.

In the present invention, the dispersant 12a is mixed with the photocatalyst A 'to disperse particles such as the photocatalyst composition 11a in the coating layer 3a, and to evenly distribute the photocatalyst composition (on the substrate 1a). 11a) to spread the particles widely, and even after wiping by the wiping means 2a, particles such as the photocatalytic composition 11a in the photocatalytic layer 4a are uniformly formed on the substrate 1a without aggregation. Therefore, the decomposition removal effect of organic substances, such as a contaminant, can be exhibited over the whole surface of the base material 1a in which the photocatalyst layer 4a was formed.

(Example)

Hereinafter, an embodiment of the present invention will be described.

First, the photocatalyst A 'is applied onto the glass plate (substrate 1a) whose surface has been cleaned in advance using the photocatalyst A' combined with the materials described in the Examples and the blending ratio, and then bulky fibers. It wiped with the cloth of and formed the photocatalyst layer 4a. In addition, for the sake of comparison, a photocatalyst which did not contain the dispersant 12a in the example was produced as a comparative example to form the photocatalyst layer 4a in the same manner.

Example 1 Combination Example of Photocatalyst (A ') of the Present Invention

Photocatalyst composition 11a... … … … Titanium oxide (TiO ₂ ), 5 mass%

Binder material 14a... … … … Silicone resin, 5 mass%

Binder aid 15a... … … … Camellia oil solution, 50% by mass

Dispersant 12a... … … … Theanine, 0.1% by mass

Organic solvent (13a). … … … Ethanol, residue

(Comparative Example)

Photocatalyst composition 11a... … … … Titanium oxide (TiO ₂ ), 5 mass%

Binder material 14a... … … … Silicone resin, 5 mass%

Binder aid 15a... … … … Camellia oil solution, 50% by mass

Organic solvent (13a). … … … Ethanol, residue

Subsequently, in Examples and Comparative Examples, the fixation state of the photocatalyst composition 11a on the glass plate (substrate 1a) after wiping was examined, and in the comparative example, the particles of the photocatalyst composition 11a were in the tens to thousands of layers. In the embodiment, formation of secondary particles was not observed, whereas particles of the individual photocatalyst compositions 11a were dispersed and evenly spread over the entire surface of the glass plate, whereas the secondary particles were laminated locally and were present locally on the glass plate. It was stuck.

In addition, the effect of the photocatalyst (A ') of this invention is not limited to the material and compounding ratio of this Example, The same effect can be acquired even if it is another material and compounding ratio which were mentioned in detail above.

Here, the photocatalyst A 'is not limited to a platinum-supported photocatalyst, but also functions significantly in the case of a platinum-supported photocatalyst.

BRIEF DESCRIPTION OF THE DRAWINGS The graph which shows the result of measuring the change of the formaldehyde concentration and the change of temperature and humidity every 30 minutes more than 24 hours in the laboratory (night fruit room) which measures the effect of this invention.

Figure 2 is a schematic perspective view showing the configuration of the photocatalyst article of the present invention.

3 is a schematic cross-sectional view taken along line 3-3 of FIG.

4 is a schematic cross-sectional view taken along line 4-4 of FIG.

5 is a schematic cross-sectional view taken along line 5-5 of FIG.

Figure 6 is a schematic perspective view showing a state of use of the sealed packaging bag containing the cleaning member of Figure 2 inside.

7 is an explanatory diagram for explaining the interior of FIG. 6;

8 shows a method for forming a photocatalyst layer of the present invention, (a) is a cross-sectional view showing the main part after applying the photocatalyst base agent, (b) is a cross-sectional view showing the main part after applying the surface coating agent, ( c) is sectional drawing which shows the principal part after drying.

 Fig. 9 is an enlarged cross-sectional view showing a part of a state in which the photocatalyst of one embodiment of the present invention is applied onto a substrate, where (a) is immediately after application and (b) is wiped off by wiping means.

Fig. 10 is an enlarged cross-sectional view showing a part of a state in which the photocatalyst of another embodiment of the present invention is applied onto a substrate, where (a) is immediately after application and (b) is wiped by wiping means.

In these drawings,

A: photocatalyst article 4: cleaning member 5: photocatalyst surface coating member

6: Member for wiping off 1: Base material 2: Photocatalyst base agent

20 photocatalytic base layer 21 binder 3 surface coating agent

30 photocatalyst layer 31 photocatalyst composition 32 dispersant

A ': photocatalyst 1a: base material 3a: coating layer

4a: photocatalyst layer 11a: photocatalyst composition 12a: dispersant

14a: binder 15a: binder aid 16a: abrasive

Claims (2)

Applying a photocatalyst base agent containing at least a binder agent and an organic solvent to the base material to form a photocatalyst base layer on the base material, A surface coating agent containing at least a photocatalyst composition and a dispersing agent is applied to the photocatalyst base layer to form a photocatalyst layer on the photocatalyst base layer. The method of forming a photocatalyst layer according to claim 1, wherein the binder contains any one of a modified epoxy resin and silicon oxide (SiO ₂ ).

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