JP2003268945A - Interior finish material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve problems of a conventional interior finish material such that a binder is decomposed and quickly degraded when a photocatalyst is directly bonded to a binder layer; a contaminant cannot be completely removed in spite of use of a photocatalyst microcapsule obtained by sealing the photocatalyst in an optically transparent microcapsule formed of a photoinactive material; and the conventional interior finish material having only an antifouling layer cannot sufficiently remove stain and cannot absorb and decompose noxious gas such as formaldehyde in a room. <P>SOLUTION: There is provided an interior finish material which is surface- treated with the antifouling layer. According to the interior finish material, the photocatalyst microcapsules which are each obtained by sealing the photocatalyst in the optically transparent microcapsule having its wall portion formed of the photoinactive material, are dispersed in the antifouling layer in a manner being exposed therefrom. By virtue of this composition, the antifouling performance of the interior finish material per se is improved, and the noxious gas generated in the room is de-composed, to thereby solve the problems of the conventional interior finish material. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interior material having an antifouling property and a toxic gas decomposing property improved by a photocatalyst.

[0002]

2. Description of the Related Art In recent years, various deodorant products, antibacterial products, etc. have been developed using materials having a photocatalytic activity represented by titanium dioxide. In many of these products, photocatalyst is in direct contact with pollutants, which decompose
It fulfills its function. However, the photocatalyst particles are
In the product in which the photocatalyst particles are in direct contact with the binder in the product compounded with the fiber or the like, there is a problem that the resin or the like is decomposed or deteriorated due to the property of the photocatalyst itself, that is, the property of decomposing organic substances. . Therefore, although these photocatalysts are encapsulated in inorganic hollow porous microcapsules to prevent the deterioration of the binder, there is a problem that it is difficult to remove the contaminants only with the microcapsules. Further, the methods disclosed in Japanese Patent Laid-Open No. 10-5598 and WO98 / 43733 have been proposed, but they were incomplete in both antifouling property and photodegradability.

[0003]

However, in the above-mentioned conventional method of fixing the photocatalyst particles to the support, when the photocatalyst particles are heated and fixed, they can be used only for the support having heat resistance. When fixing photocatalyst particles with an organic binder or mixing them into clothes or paper, the strong photocatalytic function of the photocatalyst particles decomposes the organic binder and the raw material fibers, lowering the adhesion strength and reducing the product The problem is that it causes deterioration and cannot maintain the performance that can be put to practical use.

[0004]

DISCLOSURE OF THE INVENTION The present invention relates to an interior material surface-treated with an antifouling layer, in which a photocatalyst is encapsulated in a light-transmissive microcapsule having a wall made of a photoinert substance. In the interior material surface-treated with the stain layer, the photocatalyst microcapsules in which the photocatalyst is encapsulated in the light-transmitting microcapsules whose walls are composed of a photoinert substance are dispersed in the state of being exposed on the stainproof layer. The interior material, which is characterized by that, is the gist. In the present invention, the photocatalyst microcapsule is one in which the photocatalyst is encapsulated in a porous light-transmitting microcapsule composed of a photoinert substance wall portion.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION A conceptual diagram of a photocatalyst-containing microcapsule of the present invention is shown in FIG. On the decorative layer 1 of the conventional wallpaper, the light-transmissive microcapsules composed of the porous wall portion 2 made of a photo-inactive substance which is not decomposed by light are the antifouling layer 5
Exposed above. The photocatalyst particles 3 are enclosed in the light transmissive microcapsules to obtain the photocatalyst microcapsules 4. The photocatalyst particles 3 are fixed at a portion which does not have a direct contact with the wallpaper decorative layer 1, and a harmful substance can come into contact with the photocatalyst particles 3 through the pores present in the porous wall portion 2 made of a photoinert substance. Photocatalytic functions such as antibacterial, deodorant, organic matter decomposition, and antifouling can be exhibited on the surface of particles. The photocatalyst microcapsules 4 are exposed on the antifouling layer 5 on the wallpaper decorative layer 1 to obtain the interior material 6 of the present invention.
FIG. 2 is a cross-sectional view of the interior material of the present application. The interior material 6 of the present application thus obtained has the antifouling layer 5 formed on the wallpaper decorative layer 1 and the photocatalyst microcapsules 4 on the antifouling layer. This is the interior material with the exposed structure.

That is, the present invention utilizes a photocatalyst capable of sufficiently exhibiting its photocatalytic function and firmly adhering to any support for a long period of time without impairing its photocatalytic function, thereby preventing wallpaper. Provide an interior material with improved stain resistance and indoor toxic gas removal performance.

The present invention uses photocatalyst particles in which the photocatalyst particles are enclosed in a porous wall made of a photoinert substance. The encapsulated state means a state in which the photocatalyst particles do not flow out from the photoinert substance wall portion, and such a state can be confirmed by microscopic observation. The shape of the photocatalyst powder of the present invention is preferably a microsphere, and the diameter thereof can be appropriately set depending on the application, but is 0.05 μm to 10 mm.
Is preferable, and more preferably 0.1 μm to 2 mm.
Is the range. In a preferred second method described later, that is, a method of containing an organic substance in the W / O type emulsion, the diameter is in the range of 30 to 500 μm, and further,
A more optimal photocatalyst powder having a diameter in the range of 50 to 200 μm can be obtained. Moreover, when the photocatalyst powder obtained by this preferable second method was observed with an electron microscope, it was found that fine photocatalyst powder of 1 to 10 μm was deposited on the surface of the photocatalyst powder. By taking such a form, it is possible to more effectively use the emitted light.

In the present invention, the encapsulated photocatalyst particles are particles that exhibit a photocatalytic function when irradiated with light having an energy larger than the band gap, and the photocatalyst material is titanium oxide, zinc oxide, tungsten oxide, One or more known metal compound semiconductors such as iron oxide and strontium titanate can be used. In particular, titanium oxide, which has an excellent photocatalytic function, is chemically stable, and is harmless, is desirable. What is titanium oxide?
In addition to titanium oxide, hydrous titanium oxide, hydrated titanium oxide, orthotitanic acid, metatitanic acid, and titanium hydroxide are commonly used, and the crystal form is not limited. Furthermore, in order to improve the photocatalytic function of the photocatalyst particles, V, Fe, Co, Ni, Cu, inside, and / or on the surface thereof,
At least one metal selected from the group consisting of Zn, Ru, Rh, Pt, Pd and Ag and / or a compound thereof may be contained. The particle size of the photocatalyst particles to be encapsulated is preferably fine because it has an excellent photocatalytic function, more preferably in the range of 5 to 500 nm,
The range is more preferably 10 to 500 nm, and most preferably 10 to 300 nm. Therefore, a more preferable photocatalyst particle is fine titanium oxide, that is, titanium oxide having a particle size in the range of 5 to 500 nm. More preferable photocatalyst particles are fine titanium oxides, that is, titanium oxides having a particle size in the range of 5 to 500 nm, and V, Fe, Co, Ni, C are present inside and / or on the surface thereof.
It contains at least one metal selected from the group consisting of u, Zn, Ru, Rh, Pt, Pd and Ag and / or a compound thereof.

The above-mentioned "fine particles having photocatalytic ability" (hereinafter referred to as "photocatalytic fine particles") enclosed in a photocatalyst capsule exerts a catalytic function when exposed to ultraviolet light or light in a range including visible light. However, it is not particularly limited as long as it does not react with the raw material for producing the photocatalyst capsule. For example, fine particles of at least one kind of oxides such as Ti, W, and Zn, preferably anatase-type titanium dioxide having high photoactivity are preferable. This composite fine particle of titanium dioxide and tungsten oxide, C
Titanium dioxide fine particles into which r and V are ion-implanted can be used in the visible light region. Since the photocatalyst fine particles have a very small particle size, the specific surface area is large,
More harmful gases can be adsorbed.

The light-transmissive microcapsule wall portion containing these photocatalysts is a substance that exhibits no or almost no semiconductivity or catalytic property depending on the light used for the photocatalytic reaction. As such a photo-inert substance, silicon,
Aluminum, zirconium, calcium, barium,
A compound of at least one element selected from the group consisting of strontium and magnesium is preferable. Specific examples of the above-mentioned compound include oxides such as aluminum oxide, silicon oxide and zirconium oxide, hydroxides and hydrous oxides such as aluminum hydroxide and zirconium hydroxide, sodium carbonate, potassium carbonate and sodium hydrogen carbonate. , Alkali metal such as potassium hydrogen carbonate, aluminum phosphate, phosphate such as calcium phosphate, calcium silicate, aluminum silicate, aluminum silicate, zirconium silicate, barium silicate, strontium silicate, magnesium silicate lithium silicate, sodium silicate, potassium silicate, rubidium silicate, etc. Silicates, cement, lime, silicate-containing substances such as frit for enamel, montmorillonite, kaolin,
Hydrous silicates such as talc, mica and sepiolite can be mentioned. Of alkaline earth metals such as magnesium chloride, calcium chloride, strontium chloride, barium chloride, magnesium bromide, calcium bromide, strontium bromide and barium bromide. Halides, silicon chloride, zirconium oxynitrate, zirconium oxychloride, and
Examples thereof include organic silicates such as methyl siloxane and polymethyl siloxane, and one or more of these compounds can be used. One or more of these compounds can be used. As the photoinert substance, at least one of calcium silicate, barium silicate, strontium silicate, and magnesium silicate is more preferable.

Examples of the hydrophobic organic solvent include aliphatic saturated hydrocarbons such as hexane, decane, hexadecane, isohexane and isoheptane; aliphatic unsaturated hydrocarbons such as hexene and octene; alicyclic rings such as cyclohexane and cyclohexene. Formula hydrocarbons and the like can be mentioned, and one or more of these hydrophobic organic solvents can be used.
A W / O type emulsion is prepared by mixing the compound as the photoinert substance, the suspension of photocatalyst particles and the hydrophobic organic solvent. The W / O type emulsion thus obtained is mixed with an aqueous solution of a substance which reacts with a compound contained in the W / O type emulsion to be a photoinert substance and produces a water-insoluble photoinert precipitate. Examples of the substance that produces a water-insoluble photoinert precipitate include hydrochloric acid,
Examples thereof include acids such as sulfuric acid, bases such as sodium hydroxide, halides of alkaline earth metals such as calcium chloride and magnesium chloride, and the like, which can be appropriately selected according to the type of compound used as a photoinert substance. The product obtained by mixing is then dried. Drying can be performed in any atmosphere such as the air, an inert atmosphere, and a reducing atmosphere, and the drying temperature can be room temperature to 200 ° C.

The amount of the photoinert substance is preferably in the range of 0.5 to 80% by weight, based on the weight of the photocatalyst powder.
It is more preferably in the range of 1.0 to 80% by weight, and most preferably in the range of 1.5 to 80% by weight. When the amount of the photoinert substance is less than the above range, it is difficult to successfully encapsulate the photocatalyst particles, which is not preferable because the deterioration of the support due to the contact between the photocatalyst particles and the support is likely to occur.
On the other hand, if the amount is more than the above range, it is difficult for light to efficiently reach the encapsulated photocatalyst particles and the photocatalytic function of the photocatalyst powder is deteriorated, which is not preferable.

The photocatalyst microcapsules can be produced by a known method for preparing inorganic microcapsules, and one of the preparation methods is the suspension method (W / O emulsion method). The use of is a preferable method because even fine photocatalyst particles can be included and a strong porous wall can be formed. That is, the first method of the present invention is to react a W / O type emulsion obtained by mixing a compound which becomes a photoinert substance, a suspension of photocatalyst particles and a hydrophobic organic solvent with the compound. A method for producing a photocatalyst powder, which comprises mixing a water-insoluble photo-inert precipitation-producing aqueous solution with an aqueous solution to obtain a product, and then drying the product. In the present invention, as the photocatalyst particles, those obtained by a known method can be used. For example, as a method of obtaining titanium oxide particles, (1) a method of thermally hydrolyzing titanium sulfate, titanyl sulfate, titanium chloride, titanium alkoxide, or the like in the presence of seeds for nucleation, (2) titanium chloride And (3) titanium sulfate, titanyl sulfate, titanium chloride, titanium alkoxide, etc. by adding alkali to neutralize and precipitate.
Further, the titanium oxide particles produced may be calcined or subjected to hydrothermal treatment, if necessary. In particular, those obtained by subjecting the titanium oxide particles obtained in (1) to hydrothermal treatment at 100 ° C. or higher are preferable because those having a high photocatalytic function can be obtained.

The wall of the photoinert substance is formed in a porous shape and needs to have a size that allows a fluid containing a harmful substance or the like to pass therethrough. The pore diameter of the porous material may be micropores of about 0.5 to 2 nm, mesopores of about 2 to 50 nm, or macropores of 50 nm or more, but macropores of 50 nm or more are used to suppress pressure loss of the fluid. Is preferred. On the other hand, the pore diameter of the porous material is preferably about 0.1 to 0.8 times the size of the photocatalyst particles in order to prevent the encapsulated photocatalyst particles from flowing out to the outside of the porous wall. The total area of the pores of the porous wall is preferably 5 to 80%, and more preferably 20 to 70% of the total area of the film including the pores. If the total area of the pores is smaller than the above range, the invasion speed of harmful substances and the like is slow, and further, the pressure loss is large, which is not preferable, and if it is larger than the above range, the support is likely to contact the photocatalyst particles, which is not preferable. .

The "hollow porous silica microcapsules" constituting the photocatalyst capsule are not particularly limited as long as they penetrate at least the hollow portion inside the capsule. Further, the shape and porosity of the pores are not particularly limited. It may be produced by any method as long as it does not deteriorate, deteriorate, or deteriorate the coating film in the composition or in the state of being contained in the coating film.

The fine particles may freely exist independently inside the microcapsules of the hollow porous silica, or may exist in an aggregated state. The fine particles do not have to fill the hollow portion of the microcapsule, but preferably have a space through which the pores of the microcapsule can easily come into contact with the air outside the capsule. The weight ratio of the microcapsules and the photocatalyst fine particles constituting the photocatalyst capsule is preferably 10 to 150 parts by weight, more preferably 40 parts by weight, when the microcapsule is 100 parts by weight.
~ 120 parts by weight. The concentration of the above-mentioned photocatalyst fine particles is preferably 0.1 to 20% by weight, more preferably 0.5 to 10% by weight, based on the entire composition. If the concentration of the photocatalyst fine particles is too low, sufficient photocatalytic activity may not be exhibited.

The binder used in the antifouling layer in the present invention is not particularly limited as long as it has an adhesive property such that the photocatalyst capsule can be held on the substrate. As this example, an organic binder or an inorganic binder can be preferably used. Examples of organic binders include
Acrylic-styrene resin, vinyl acetate resin, epoxy resin, polyurethane resin, polyester resin, PV
A, urea resin, phenol resin, fluororesin, etc. may be mentioned. These can be used alone or in combination of two or more. Further, it may be water-based or solvent-based, and in the case of water-based one, an emulsion is preferable. Examples of inorganic binders include silicone resins, cement, water glass, enamel and the like. These can be used alone or in combination of two or more.

The content ratio of the photocatalyst capsule and the binder contained in the photocatalyst capsule-containing coating composition of the present invention is as follows. That is, the total content of the photocatalyst capsule and the binder is 100% by weight.
In that case, the content of the binder is preferably 0.1 to 10% by weight, more preferably 0.5 to 8% by weight, and further preferably 1 to 5% by weight. If the amount of the binder is too large, the photocatalyst capsules are likely to be embedded in the film obtained by coating, while if the amount is too small, the adhesiveness to the substrate tends to be poor.

The photocatalyst microcapsules thus obtained are mixed with the antifouling binder to coat the surface of the interior material. As the coating method, spraying is carried out by an ordinary method such as an impregnation method, a dip coating method, a spinner coating method, a blade coating method, a roller coating method, a wire bar coating method, a reverse roll coating method or a spray coating method. It is carried out at a temperature of room temperature to 200 ° C. under an arbitrary atmosphere such as an active atmosphere or a reducing atmosphere.

Next, in the present invention, the interior of the photocatalytic microcapsule is cleaned by bringing it into contact with an environmental pollutant under light irradiation. As the environmental pollutants,
Environmental pollution such as oil and organic pollutants, ammonia, mercaptans, aldehydes, amines, hydrogen sulfide, hydrocarbons, sulfur oxides, nitrogen oxides and other air pollutants, bacteria, fungi, microorganisms, and various contaminants It can be a substance or the like. These environmental pollutants can be used with blowers and liquid blowers, or by using natural convection and movement,
It is brought into contact with the photocatalyst powder and purified by the photocatalytic function.
In this way, the organic contaminants contained in the microcapsules are also completely decomposed by the photocatalyst.

As the light source used in the purification method of the present invention,
A light source capable of emitting light having energy larger than the band gap of the photocatalyst particles is required, and for example, a natural light source such as the sun, an ultraviolet lamp, a black light, a mercury lamp, a xenon lamp, an artificial light source such as a fluorescent lamp, an incandescent lamp, etc. Can be used. The light reaches the encapsulated photocatalyst particles by passing through the porous wall made of the photoinert substance, scattered on the particle surface of the photoinert substance, or entering through the pores of the porous wall.

According to the present invention, stains of organic substances which could not be completely removed by the conventional antifouling resin layer could be completely decomposed and removed by the photocatalyst in the microcapsules. In addition, stains that could not be removed by only the photocatalyst could be removed by combining with the antifouling layer.

For use in the present invention, the photocatalyst microcapsules are exposed on the surface of interior materials such as wallpaper. As the interior material, a ceramic material, an inorganic material such as glass fiber, a polymer, cloth, paper or other organic fiber material can be used. In particular, a photocatalyst using paper as a support can be used for interior materials such as shoji, bran, wallpaper, etc. for indoor photodeodorization, antifouling and antibacterial.

[0024]

The photocatalyst microcapsules in which the photocatalyst particles are enclosed in the porous wall of the photoinert substance can contact the photocatalyst particles with harmful substances, organic substances such as dirt, etc. that have entered through the pores, and have a desired photocatalytic function. Is obtained, and further,
Since it can be fixed on the interior material through the porous wall made of a photoinert substance formed on the outside of the photocatalyst particle, even if the interior material is weak and does not have resistance to oxidizing power, the interior material is It is possible to stably fix the photocatalyst particles without being affected by the oxidizing power. Further, in the present invention, the antifouling layer prevents a large amount of stains in advance, and the stains that cannot be prevented are decomposed by the photocatalyst in the microcapsules. INDUSTRIAL APPLICABILITY According to the present invention, an interior material having more antifouling performance and toxic gas decomposability can be obtained.

[0025]

EXAMPLE A commercially available wallpaper surface was coated with a mixture of acrylic-styrene resin antifouling resin and a photocatalyst microcapsule in a thickness of 2
After applying 0 μ, it was dried to obtain the wallpaper of the present invention. Photocatalyst microcapsules were exposed to the obtained wallpaper and were sprayed. The titanium oxide photocatalyst was enclosed in a sodium silicate photocatalytically inactive wall which was porous and permeable to light and gas.

(Production Method of Photocatalyst Microcapsules) Titanium oxide suspension was prepared by mixing 5 g of titanium oxide having a particle diameter of 20 nm, 4.7 ml of an aqueous sodium silicate solution as a photoinactive substance, and 5.3 ml of pure water. 100 g of this susnibenzene, 1 g of sorbitan monostearate and 2 g of polyoxymethylene sorbitan monooleate as a surfactant, and 20 ml of a calcium chloride solution as an inert wall material were mixed and filtered to obtain microcapsules.

A chemical of a predetermined concentration was added at a constant concentration every hour, and after 6 hours, the amount of toxic gas adsorbed on the blank and the wallpaper of the present invention was measured. The results are shown in "Table 1".

[0028]

[Table 1]

In this way, a wallpaper having excellent performance of absorbing and decomposing toxic gases was obtained. Further, according to the present invention, it is possible to completely remove stains of organic substances which cannot be completely removed only by the conventional antifouling layer, by decomposing the organic substances in the microcapsules with a photocatalyst.

[0030]

INDUSTRIAL APPLICABILITY According to the present invention, a photocatalyst microcapsule in which photocatalyst particles are enclosed in a porous wall made of a photoinactive substance allows harmful substances and the like to enter through pores and come into contact with the photocatalyst particles. To obtain the photocatalytic function of
Further, since the photocatalyst particles can be fixed on the interior material through the porous wall made of a photoinert substance formed on the outer side of the photocatalyst particles, the photocatalyst particles can be applied to the interior materials which are vulnerable to oxidizing power such as paper and fiber. Can be firmly fixed for a long period of time. Further, the present invention is a photocatalyst characterized in that the photocatalyst particles are adhered to a support, having a desired photocatalytic function, and easy to separate and handle from the treatment system, and , Can be manufactured at low cost. Further, in the present invention, the interior material using the photocatalyst-containing microcapsules is environmentally purified, and environmental pollutants such as formaldehyde can be efficiently and easily purified. As described above, according to the present invention, the antifouling property of the interior material and the indoor absorption and decomposability of harmful gas were improved, and the interior material was not soiled for a long period of time.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a photocatalyst microcapsule.

FIG. 2 is a sectional view of an interior material.

[Explanation of symbols]

2 ... Porous wall 3 ... Photocatalyst particles 4 ... Photocatalyst microcapsules 5 ... Antifouling layer 6 ... Interior material of the present invention

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2E110 AA64 AB04 AB23 BA02 BA12                       BB03 GA32W GA33W GB12W                 4G069 AA02 BA01A BA02A BA04A                       BA04B BA05A BA06A BA15A                       BA15B BA16A BA29A BA29B                       BA48A BB04A BB06A BB08A                       BB16A BC09A BC12A BC13A                       BC35A BC50A BC60A BC66A                       CA01 CA11 EE01

Claims (2)

[Claims] 1. An interior material surface-treated with an antifouling layer,
An interior material, wherein photocatalyst microcapsules in which a photocatalyst is encapsulated in light-transmissive microcapsules whose walls are made of a photoinert substance are dispersed in an exposed state on the antifouling layer. 2. The interior material according to claim 1, wherein the light-transmissive microcapsules are porous.