Formation of optically active coating layer

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a method for forming a multifunctional coating film that exhibits a deodorizing function, an antibacterial function, an antifouling function, and an air purification function.

【0002】

[Conventional technology]

Conventionally, there is no paint that has functions such as deodorization and antibacterial at the same time in the paints that are painted on the ceiling, inner wall, floor, etc. of houses and buildings, and the deodorizing paints include iron compounds, ethylenediamine tetraacetic acid and myoban. As a paint containing the above and an antibacterial paint, a paint containing a silver silica gel-based antibacterial agent and the like are known, but at present, a paint having both a deodorizing function and an antibacterial function has not been established.

【0003】

[Problems to be Solved by the Invention]

An object of the present invention is to solve the above problems and to provide a method for forming a multifunctional coating film which has both a deodorizing function and an antibacterial function, and is also excellent in an antifouling function and an air purification function.

【0004】

[Means for solving problems]

As a result of conducting research to solve the above problems, the present inventors have made a metal of titanium oxide and zinc having photocatalytic activity on a hydrolyzable silicon compound or a solvent-soluble fluororesin on a base material that has been subjected to a base treatment. Alternatively, it was found that by applying a paint containing a specific amount of oxide and further polishing the surface to create an active surface on the surface layer, it is excellent in deodorizing function, antibacterial function, antifouling function, and air purification function. .. The present invention has been completed based on such findings.

【0005】

That is, the present invention comprises (A) a silyl group-containing vinyl-based copolymer having hydrolyzability, a hydrolyzate of organosilane, and a partial condensate of the hydrolyzate of organosilane on the base-treated substrate. At least one hydrolyzable silicon compound or solvent-soluble fluororesin selected from the group, (B) titanium oxide having photocatalytic activity, and (C) a metal or oxide of zinc are blended, and the PWC of the titanium oxide is blended. It is a method for forming a coating film having photochemical activity, which comprises applying a coating material having a value of 45 to 85 to form a coating film.

【0006】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail.

【0007】

In the method for forming a coating film having photochemical activity of the present invention, the base material is not particularly limited to a metal plate, an inorganic plate, a wood plate, a plastic base material, etc., whose surface is previously subjected to a base treatment. Examples of the metal plate include various metal plates such as a steel plate, an aluminum plate, a stainless plate, and a titanium plate. Among these, examples of steel sheets include cold-rolled steel sheets, hot-rolled steel sheets, galvanized steel sheets, alloy zinc-plated steel sheets, zinc-iron alloy-plated steel sheets, zinc-aluminum alloy-plated steel sheets, aluminum-plated steel sheets, chrome-plated steel sheets, and nickel-plated steel sheets. Examples include steel sheets, galvanized galvanized steel sheets, tin-plated steel sheets, etc. Examples of the base treatment include water washing, hot water washing, pickling, alkaline degreasing, polishing, chromate treatment, phosphoric acid treatment, galvanized zinc phosphate treatment, blasting treatment, and composite. Pre-coating is performed by either alone or in combination with oxide film treatment, and if necessary, polyester-based, epoxy-based, and urethane-based primers are applied to roll coaters, curtain flow coaters, roller curtain coaters, electrostatic coating machines, blade coaters, and die coaters. Then, leave it at room temperature, or cure and dry it in a hot air furnace, an induction heating furnace, a combined induction heating and hot air furnace, a near-infrared furnace, a far-infrared furnace, an active energy ray irradiation furnace, etc. according to a conventional method. Usually, it is obtained by coating with a film thickness of about 0.5 to 30 μm. Examples of inorganic boards include slate boards used for exterior wall materials and interior materials, wood piece cement boards, pulp cement boards, asbestos cement boards, lightweight aggregate-mixed cement boards, foamed concrete boards, glass fiber reinforced cement boards, and calcium silicate. Examples thereof include a plate, a magnesium carbonate plate, and other water-hard plate materials, which are obtained by applying a sealer such as urethane-based, epoxy-based, or vinyl-based. Examples of the wood board include a sealing treatment, a polishing treatment, and a wood sealer coating. Examples of the plastic-based base material include application of various plastic primers.

【0008】

The hydrolyzable silicon compound used in the present invention was selected from the group consisting of a hydrolyzable silyl group-containing vinyl-based copolymer, a hydrolyzate of organosilane, and a partial condensate of the hydrolyzate of organosilane. These can be used alone or in combination of two or more.

【0009】

The silyl group-containing vinyl-based copolymer includes at least one ethylenically unsaturated monomer containing at least one group of the general formula (I):> C = C <and a silyl group of the following general formula (II). It is a copolymer containing at least one containing monomer.

【0010】

RSiX_n R¹_(3-n) (II) [0011]

(In the formula, R is a monovalent organic group containing a vinyl group, R¹ Is selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an aryl group or an aralkyl group, and X is a halogen, alkoxy, alkoxyalkoxy, acyloxy, ketoximate, amino, acid amide, aminooxy, mercapto, and alkenyloxy group. The hydrolyzable group, n is an integer of 1 to 3.

【0012】

Examples of the silyl group-containing monomer include γ-methacryloxypropyltrimethoxysilane, vinyltriethoxysilane, vinyl-tris (2-methoxyethoxysilane and the like).

【0013】

Further, examples of the ethylenically unsaturated monomer suitable for producing the silyl group-containing vinyl-based copolymer include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, and butyl. Alkyl acrylates such as methacrylate, 2-methylhexyl methacrylate and lauryl methacrylate; vinyl aromatic hydrocarbons such as styrene, vinyltoluene and α-methylstyrene; vinyl halides such as vinyl chloride; vinylidene halides such as vinylidene chloride; butadiene, Conjugated ethylene such as isoprene; There are vinyl esters of saturated fatty acids having 1 to 12 carbon atoms, vinyl acetate, vinyl propionate and the like, and these can be used alone or in combination of two or more.

【0014】

When the silyl group-containing vinyl-based copolymer of the present invention is produced, the ethylenically unsaturated monomer and the silyl group-containing monomer can be used in an arbitrary ratio, but the silyl group-containing monomer can be used. Is preferably used in a proportion of 0.5 to 25 mol%, and the ethylenically unsaturated monomer is preferably used in a proportion of 99.5 to 75 mol%. When producing this copolymer, a conventionally known method can be used. The molecular weight of the silyl group-containing vinyl-based copolymer is preferably 3,000 to 1,000,000, particularly preferably 10,000 to 300,000.

【0015】

The hydrolyzate of organosilane used in the present invention is a compound represented by the following general formula (III-A), (III-B) or (IV).

【0016】

R² Si (OR³ )₃ (III-A) Si (OR³ )₄ (III-B) R²₂Si (OR³ )₂ (IV) [0017]

(In the formula, R² Is an organic group with 1 to 8 carbon atoms, R³ Is an alkyl group with 1 to 4 carbon atoms, and each R² , R³ May be the same or different.

【0018】

Further, in the present invention, a partially condensed compound of the compound represented by the general formula (III-A), (III-B) or (IV) can be used. In the present invention, the hydrolyzate of organosilane or a partial condensate thereof is one component that acts as a binder. The polystyrene-equivalent molecular weight of the partially condensed compound is 1,000 to 5,000, preferably 1,500 to 3,000.

【0019】

When this hydrolyzate or a partial condensate thereof is used, it is preferable to use a solvent solution containing 10 to 80% by weight of a solid content.

【0020】

Organic group R in the above general formula (III-A), (III-B) or (IV)² Specific examples of the above are alkyl groups such as methyl group, ethyl group, n-propyl group, i-propyl group and i-butyl group, γ-chloropropyl group, vinyl group, 3,3,3-trifluoropropyl. There are a group, a γ-glycidoxypropyl group, a γ-methacryloxypropyl group, a γ-mercaptopropyl group, a phenyl group, a 3,4-epoxycyclohexylethyl group and the like. Also, the alkyl group R³ Specific examples of the above include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, sec-butyl group, tert-butyl group and the like.

【0021】

Also, the general formula, (III-A) Specific examples of the organosilanes shown in are as follows: methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane: , I-propyltrimethoxysilane, i-propyltriethoxysilane, γ-chloropropyltrimethoxysilane, γ-chloropropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 3,3,3-trifluoropropyl Trimethoxysilane, 3,3,3-trifluoropropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxy Propyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3,4-epoxycyclohexylethyltrimethoxysilane, 3,4-epoxycyclohexylethyltri Ethoxysilane, i-butyltrimethoxysilane, i-butyltriethoxysilane and the like, and methyltrimethoxysilane and methyltriethoxysilane are particularly preferable.

【0022】

Specific examples of the organosilane (alkylsilicate) represented by the general formula (III-B) are tetramethylsilicate, tetraethylsilicate, tetra-n-propylsilicate, tetra-i-propylsilicate, and tetra-n-butyl. There are silicate, tetra-i-butyl silicate, tetra-sec-butyl silicate and the like. Specific examples of the organosilane of (IV) above include dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, di-i-propyldimethoxysilane, and di-i-propyldiethoxysilane. , Di-i-propyldimethoxysilane, di-i-propyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane and the like, and dimethyldimethoxysilane and diethyldiethoxysilane are particularly preferable. In the present invention, these hydrolyzable silicon compounds can be used alone or in combination of two or more.

【0023】

When these organosilanes of the general formulas (III-A), (III-B) and (IV) are used in combination, the mixing ratio (weight ratio) of (III-A) to (III-B) in terms of organosilanes. Is 100: 0 to 30 (that is, it may not contain (III-B)), and the mixing ratio of the total amount of (III-A) and (III-B) to (IV) in terms of organosilane (IV) The weight ratio) is preferably 100: 5 to 150, particularly preferably 100: 10 to 120. When the mixing ratio of the organosilanes of the general formula (IV) is larger than the above range, cracks are likely to occur in the formed coating film, and conversely, when it is smaller than the above range, the curability is lowered and the coating film is coated. The film hardness tends to decrease.

【0024】

In the present invention, the hydrolyzate of the organosilane or a partial condensate thereof is used, and water is added to carry out this hydrolysis and partial condensation. The amount of water added is usually 0.1 to 1.0 mol, particularly preferably 0.15 to 0.7 mol, based on 1 equivalent of the alkoxy group of the organosilanes of the general formulas (III-A), (III-B) and (IV). .. If the number of moles of water added is smaller than the above range, storage stability tends to deteriorate, and if the number of moles of water added is larger than the above range, curing and drying tends to be delayed. Further, a production accelerator may be used to produce such a condensate of organosilane.

【0025】

As such an accelerator, the general formula (V): M (OR)_x A compound represented by, mineral acid, or the like can be used. In the general formula (V), M is a metal such as Ti, Al, B, Zr, R is an alkyl group having 2 to 5 carbon atoms, and x is an integer of 2 to 4.

【0026】

Specific examples of the general formula (V) include tetra-i-propoxytitanium, tetra-n-butoxytitanium, tri-i-propoxyaluminum, mono-sec-butoxy-di-i-propoxyaluminum, diethoxyboron, Di-n-propoxyboron, tetra-n-butoxyzirconium and the like, and hydrochloric acid, sulfuric acid and the like as mineral acids. The amount added is preferably in the range of 0.05 to 2.0 parts by weight with respect to 100 parts by weight of organosilane.

【0027】

The solvent-soluble fluororesin used in the present invention is not particularly limited as long as it is soluble in an organic solvent usually used for paints, and conventionally known fluorine-containing copolymers can be used, and they are curing agents. It can be used without particular limitation, such as a lacquer type that cures without using, a self-crosslinking type, a room temperature curing type that is used in combination with a curing agent, and a baking curing type.

【0028】

Specifically, for example, Japanese Patent Application Laid-Open No. 57-34107, Japanese Patent Application Laid-Open No. 57-78270, Japanese Patent Application Laid-Open No. 59-102961, Japanese Patent Application Laid-Open No. 59-120661, Japanese Patent Application Laid-Open No. 59-197471, Japanese Patent Application Laid-Open No. 60 -28458, Japanese Patent Application Laid-Open No. 61-12760, Japanese Patent Application Laid-Open No. 61-43667, Japanese Patent Application Laid-Open No. 61-57609, Japanese Patent Application Laid-Open No. 61-115967, Japanese Patent Application Laid-Open No. 61-200145, Japanese Patent Application Laid-Open No. 61-247727 No., JP-A-61-258852, JP-A-62-84137 and the like, the fluorine-containing copolymers and modified products of the copolymers are typical fluorine-containing copolymers. It is not limited to.

【0029】

Specific examples of copolymers include fluoroolefins, functional group-containing vinyl ethers, functional group-free vinyl ethers and / or carboxylate vinyl esters and other copolymers containing comonomers as essential components; fluoroolefins, A copolymer containing cycloalkyl vinyl ether, alkyl vinyl ether, and hydroxyalkyl vinyl ether as essential components; a copolymer obtained by reacting a copolymer of fluoroolefin, alkyl vinyl ether, and hydroxy vinyl ether with a dibasic acid anhydride to partially carboxylate the copolymer. A hydroxyl group-containing copolymer obtained by hydrolyzing a copolymer with at least one perhaloolefin selected from tetrafluoroethylene and chlorotrifluoroethylene, vinylidene fluoride, vinyl ester and other monomers; tetrafluoro Copolymer consisting of at least one perhaloolefin selected from ethylene and chlorotrifluoroethylene, α-olefin, hydroxyalkyl vinyl ether and other comonomonic; chlorotrifluoroethylene, tetrafluoropropyl vinyl ether and functional group A copolymer consisting of one or more vinyl ethers having a hydroxyl group, a glycidyl group or an amino group; difluoroethylene and a monomer having a functional group such as a hydroxyl group, a glycidyl group or a carboxyl group and tetrafluoroethylene or chloro. Examples thereof include copolymers of trifluoroethylene, and such commercially available products include Lumiflon LF100, Lumiflon LF200, Lumiflon LF210, Lumiflon LF300, Lumiflon LF400, Lumiflon LF500, Lumiflon LF554, Lumiflon LF916 (trade name manufactured by Asahi Glass Co., Ltd.); JZ-111-60, Fluonate HZ-1148-60, Fluonate K-700, Fluonate K-702, Fluonate K-703, Fluonate K-704 (trade name manufactured by Dainippon Ink and Chemicals Co., Ltd.); Cefral coat manufactured by Central Glass Co., Ltd. Mitsubishi Rayon Dianal LR-2504, Dianal AR-2126;Toray Industries Co., Ltd. Coatax FX-68, Coatax FX-96, Coatax FX-145, etc. are typical examples.

【0030】

Further, the solvent-soluble resin of the present invention is soluble in an organic solvent having a low polarity and alone such as xylene and toluene, but it is also possible to use a mixture of other organic solvents if necessary. .. Other organic solvents include cyclic ethers such as tetrahydrofuran and dioxane, aromatic hydrocarbons such as benzene, toluene and xylene; esters such as ethyl acetate and butyl acetate; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone. Nitrogen-containing solvents such as dimethylformamide, dimethylacetamide and pyridine; halogen-containing solvents such as 1,1,1-trichloroethane and trichloroethylene can be mentioned.

【0031】

The solvent-soluble fluororesin of the present invention can be produced by solution polymerization in the presence of a normal radical initiator.

【0032】

What is titanium oxide having photocatalytic activity used in the present invention?₂ The sol is applied to the substrate material to form a thin film, and the thin film is coated or impregnated with an aqueous solution of a metal salt having a catalytic function or a suspension of fine metal powder, and then rutile-type TiO.₂ Anatase-type TiO by heat treatment at a temperature of 800 ° C or lower, which is a temperature below the phase transition point to₂ It is made by immobilizing the metal on a thin film.

【0033】

The above TiO₂ The sol is an anatase-type TiO having an average particle size of about 0.01 to 0.05 μm in an acidic aqueous solution such as nitric acid or hydrochloric acid or a basic aqueous solution such as ammonia.₂ Is present in the sol state in a few percent to several tens of percent. Examples of the metal having a catalytic function include Cu, Ag, Fe, Pd, Pt and the like, and examples of the salt may be nitrate, sulfate, acetate and the like.

【0034】

The zinc metal or oxide used in the present invention is a generally known zinc powder, and is not particularly limited, and various metals are used. The average particle size of zinc powder is 1 to 20 μm, preferably 1 to 10 μm. Further, the zinc powder may be an alloy of zinc and other metals such as iron, calcium, sodium, potassium and aluminum. Examples of the oxide include zinc oxide.

【0035】

The zinc metal or oxide is added for the purpose of removing Nox.

【0036】

The mixing ratio of the metal or oxide of titanium oxide and zinc having photocatalytic activity is 80:20 to 99: 1, preferably 85:15 to 95: 5. If the blending ratio of the metal or oxide of zinc exceeds 20% by weight, zinc covers titanium oxide and reduces the photocatalytic effect, which is not preferable. On the contrary, if it is less than 1% by weight, the addition effect is not recognized, which is not preferable.

【0037】

The coating composition of the present invention comprises the above-mentioned component (A), component (B) and component (C), and is blended so that the PWC is 45 to 85, preferably 50 to 80.

【0038】

Here, PWC stands for Pigment Weight Concentration and is calculated by the following formula.

【0039】

<img file="JPH10251558A_D0001.tif" />【0040】

If the PWC is less than 45, the photocatalytic effect will not be fully exhibited. On the contrary, if it exceeds 85, the film forming property is lowered and cracks, peeling, etc. occur, which is not preferable.

【0041】

Further, it is possible to replace a part of the photocatalytic titanium oxide of the present invention with at least one selected from the group consisting of activated carbon, silica gel, zeolite, and calcium phosphate. Examples of the calcium phosphate include α-tricalcium phosphate, β-tricalcium phosphate, tetracalcium phosphate, octacalcium phosphate, hydroxyapatite and the like, and hydroxyapatite is particularly preferable.

【0042】

The coating composition of the present invention can be used as a coating material by adding various pigments, organic solvents, additives and the like to the coating composition described above as needed.

【0043】

As the pigment, a pigment usually used for paints can be used as it is. Specifically, colored inorganic pigments such as titanium oxide, zinc oxide, iron oxide, and yellow lead, colored organic pigments such as phthalocyanine blue and benzidine yellow, extender pigments such as quartz powder, alumina oxide, and precipitated barium sulfate, and stainless steel powder. Typical examples are metal powders such as zinc powder, aluminum powder, bronze powder, and mica powder.

【0044】

Examples of the organic solvent include hydrocarbon solvents such as toluene and xylene; ester solvents such as ethyl acetate and butyl acetate; ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and isophorone; methanol, ethanol, butanol and the like. Alcoholic solvents and the like are typical examples.

【0045】

In addition, examples of the additive include additives usually known as additives for paints such as surface conditioners, dispersants, ultraviolet absorbers, thickeners, and reaction adjustment catalysts.

【0046】

The paint thus obtained can be applied not only to various metal materials such as steel plates, stainless plates and aluminum plates, but also to inorganic materials such as mortar, concrete and glass, and to paint plastics and wood.

【0047】

As the coating method, conventional methods such as air spray, airless spray, electrostatic spray, shower coat, dip coating, brush coating, and roll coating can be adopted as they are.

【0048】

[Example]

Hereinafter, the present invention will be described in more detail with reference to Examples.

【0049】

In the examples, "part" and "%" are shown on a weight basis.

【0050】

&lt;Preparation of hydrolyzed condensate solution of organoalkoxysilane&gt; 40 parts of methyltriethoxysilicate and 54 parts of isopropyl alcohol are stirred and mixed at 40 ° C, and then a mixture of 0.3 parts of 0.1N-hydrochloric acid and 5.7 parts of water is added. It was added dropwise over 90 minutes. After the dropping, the mixture was further stirred at 40 ° C. for 4 hours to obtain a hydrolyzed condensate solution of methyltriethoxysilicate having a non-volatile content of 40% "hereinafter referred to as hydrolyzed condensate A-1". The polystyrene-equivalent weight average molecular weight of the condensate was 10,000.

【0051】

&lt;Preparation of hydrolyzed condensate solution of tetraalkoxysilicate&gt; Tetraethoxysilicate ["Ethylsilicate 40" (trade name manufactured by Nippon Corcote Co., Ltd.)] 35 parts and 61 parts of isopropyl alcohol are stirred and mixed at 40 ° C, and then mixed. A mixture consisting of 1 part of 1N-hydrochloric acid and 3 parts of water was added dropwise over 90 minutes. After the dropwise addition, the mixture was further stirred at 40 ° C. for 4 hours to obtain a hydrolyzed condensate solution of tetraethoxysilicate having a non-volatile content of 35% [hereinafter referred to as hydrolyzed condensate A-2]. The polystyrene-equivalent weight average molecular weight of the condensate was 13,000.

【0052】

&lt;Preparation of silyl group-containing vinyl resin solution&gt; 45 parts of xylene and 40 parts of isobutanol were added and mixed, and then heated to 85 ° C with stirring. Next, a mixed solution of 50 parts of isobutyl methacrylate, 35 parts of 2-ethylhexyl methacrylate, 15 parts of γ-methacryloxypropylmethoxysilane and 1.5 parts of azobisisovaleronitrile was added dropwise at 85 ° C over 3 hours, and then 90 ° The temperature was raised to C and maintained for 2 hours to terminate the reaction to obtain a silyl group-containing vinyl resin solution having a non-volatile content of 55% [hereinafter referred to as vinyl resin B]. The vinyl resin has a weight average molecular weight of 14,000 and has an average of about 7 silyl groups per polymer molecule.

【0053】

&lt;Preparation of paint&gt; The components shown in Table 1 were mixed, and a paint was prepared using a paint shaker using glass beads as a dispersion medium.

【0054】

&lt;Undercoat&gt; Acrylic copolymer consisting of methyl methacrylate / butyl acrylate / 2-hydroxymethyl acrylate = 70/20/10: 10 parts, hexamethylene diisocyanate trimethylolpropane adduct: 4 parts, tolylene diisocyanate trimmer: 3 parts , Titanium white: 15 parts, Kaolin: 8 parts, Mica: 8 parts, Barium sulfate: 4 parts, Butyl acetate: 20 parts and Xylene: 28 parts.

【0055】

[Examples 1 to 7, Comparative Examples 1 to 3] A varnish 100 of a curing accelerator (dibutyltin laurate) was applied to the paint shown in Table 1 on the surface of a slate plate (50 x 100 mm, thickness 5 mm) coated with an undercoat paint. 0.1 part was added to each part and further dried at 100 ° C for 10 minutes to form a coating film so that the dry film thickness was about 30 μm, and various tests were performed. The results are shown in Table 2.

【0056】

&lt;Acetaldehyde reduction rate&gt; 4.0 mW / cm using black light for 5 cm of data in an atmosphere with an acetaldehyde concentration of 1000 ppm² Irradiate ultraviolet rays with the intensity of. The gas concentration in the atmosphere is measured at 15-minute intervals to determine the rate of decrease in acetaldehyde.

【0057】

&lt;NOx removal rate&gt; The test method and conditions are shown below and in Fig. 1.

[Test method] [0058] [0058]

Exposure container 12 x 24 cm Exposed window pyrex glass Panel 10 x 10 cm² Panel-Exposure window spacing 0.5 cm Light source Toshiba black light (15W; 20cmL; 2) Irradiation distance 20 cm Main wavelength 354nm UV-A amount 0.4mW / cm² Inlet gas composition NOx 6ppm + air Gas flow rate Flow rate 3 liters / min Line speed 8.3 cm / sec NOx Meter Shimadzu CLM-500 Chemiluminescent Sensitivity full scale 10ppm ± 0.2ppm Condition adjustment The above gas is distributed for 2 hours in a dark atmosphere. [0059]

[table 1]

<img file="JPH10251558A_D0002.tif" />【0060】

[Table 2]

<img file="JPH10251558A_D0003.tif" />【0061】

Note 1) Solvent-soluble fluororesin; Non-volatile content 60 ± 1% (Product name manufactured by Asahi Glass Co., Ltd.) Note 2) Photocatalytic titanium oxide; SSP-20 (trade name manufactured by Sakai Chemical Industry Co., Ltd., average particle size 0.7 μm, specific surface area 170 m² / g) Note 3) Zinc powder; Product name manufactured by Honjo Chemical Co., Ltd. Note 4) Non-yellowing isocyanate; 100% non-volatile (trade name manufactured by Nippon Polyurethane Industry Co., Ltd.) Note 5) NOx removal rate (%) = (1-Outlet NOx concentration / Inlet NOx concentration) x 100 [0062]

[Effect of the invention]

The coating film forming method of the present invention has both a deodorizing function and an antibacterial function, and is also excellent in an antifouling function and an air purification function.

[Simple explanation of drawings]

[Figure 1]

It is a figure which shows the measuring method of a NOx removal rate.