JP7482297B2 - Photocatalyst Products - Google Patents

Description

An embodiment of the present invention relates to a photocatalytic product.

Photocatalysts generate electrons and holes excited by light, and have strong oxidizing power. This oxidizing power is used as a catalytic action to decompose and remove harmful organic molecules, sterilize, and maintain the hydrophilicity of substrates. When photocatalysts are applied to inorganic substrates such as glass substrates, they can exert a catalytic action on the surrounding atmosphere. On the other hand, nonwoven wallpaper and cloth products contain many different organic components because they are treated with chemical agents or dyed. Therefore, when photocatalysts are applied to organic substrates such as nonwoven fabrics, they adsorb and decompose many harmful organic molecules from the organic substrate, which reduces the catalytic action on the surrounding atmosphere.

Patent No. 5481629 International Publication No. 2015/056486

The objective of this embodiment of the present invention is to obtain a photocatalytic product that has good catalytic action on the surrounding atmosphere.

According to an embodiment, a porous substrate and
A surface treatment portion is provided on the porous substrate,
The surface treatment section provides a photocatalyst product comprising an ammonium zirconium carbonate layer on the porous substrate, and a photocatalyst layer containing tungsten oxide on the ammonium zirconium carbonate layer.

FIG. 2 is a model diagram showing the configuration of a photocatalyst product according to the first embodiment. FIG. 11 is a model diagram showing another configuration of the photocatalyst product according to the first embodiment. FIG. 11 is a model diagram showing another configuration of the photocatalyst product according to the first embodiment. FIG. 11 is a model diagram showing another configuration of the photocatalyst product according to the first embodiment. FIG. 11 is a model diagram showing the configuration of a photocatalyst product according to a second embodiment. FIG. 2 is a graph showing the catalytic action of a photocatalyst product according to an embodiment. FIG. 11 is a graph showing the catalytic action of another sample of the photocatalyst product according to the embodiment. FIG. 2 is a graph showing the catalytic effect of a comparative photocatalytic product. FIG. 2 is a graph showing the catalytic action of the photocatalyst product according to the embodiment. FIG. 2 is a graph showing the catalytic effect of a comparative photocatalytic product. 1 is a SEM photograph of the surface of a porous substrate used in an embodiment. 1 is a SEM photograph of the surface of a photocatalyst product according to an embodiment. 1 is a photograph of a black cloth surface showing the results of a transfer test of a photocatalyst product according to an embodiment. 1 is a photograph of a black cloth surface showing the results of a photocatalyst transfer test of a photocatalyst product according to an embodiment. FIG. 1 is a graph showing the relationship between light irradiation time and the residual rate of acetaldehyde.

The photocatalyst product according to the embodiment includes a porous substrate and a surface treatment portion provided on the porous substrate. The surface treatment portion includes at least one of a clay mineral including smectite or ammonium zirconium carbonate, and a photocatalyst containing tungsten oxide.
According to the embodiment, by using at least one of clay minerals containing smectite or ammonium zirconium carbonate in the surface treatment portion, when an organic substrate is used as the porous substrate, gas emission from the organic substrate can be prevented. In addition, it is possible to prevent the emission of, for example, aldehyde-based gases that are generated by the contact of the photocatalyst with the organic components in the organic substrate and the photocatalytic reaction. This provides a good catalytic action of the photocatalyst to the surrounding atmosphere. In addition, it is effective for the photocatalytic action when an organic porous substrate, particularly a nonwoven wallpaper or a cloth product, is used as the porous substrate.

The photocatalyst products according to the embodiments can be divided into photocatalyst products according to the following first embodiment, second embodiment, and third embodiment.
The photocatalyst product according to the first embodiment includes a porous substrate and a surface treatment portion provided on the porous substrate, the surface treatment portion including a clay mineral including smectite and a photocatalyst containing tungsten oxide.
Smectite is a silicate mineral having a layered crystal structure. Examples of smectite that can be used in the embodiment include saponite, hectonite, montmorillonite, and stevensite. Smectite that has a high aspect ratio, a shape in which thin-film crystals are stacked, and has high transparency can be used.

According to the first embodiment, the porous substrate is surface-treated with smectite, which has a shape in which thin-film crystals are laminated, and the barrier properties of the porous substrate against organic components are improved. For example, when a photocatalyst is used on an organic substrate coated with an aqueous dye in which an acrylic emulsion is dispersed, the organic matter, which is a component of the acrylic emulsion, is dissolved from the organic substrate and covers the photocatalyst. In contrast, if the organic substrate is treated with smectite, the dissolved organic matter is prevented from coming into contact with the photocatalyst, and deterioration of the photocatalyst performance and the release of aldehyde or carboxylic acid gases associated with the reaction between the organic matter and the photocatalyst can be prevented. In addition, the photocatalyst can be prevented from coming into direct contact with the organic substrate and reacting with it. This allows a photocatalyst product with good catalytic action in the surrounding atmosphere to be obtained.

FIG. 1 shows a model diagram showing the configuration of a photocatalyst product according to the first embodiment.
As shown in the figure, the photocatalyst product 10 according to the first embodiment includes, for example, a porous substrate 1 and a surface treatment section 4 provided on the porous substrate 1. The surface treatment section 4 includes a clay mineral layer 2 and a photocatalyst layer 3 formed in order on the porous substrate 1. When a substrate having an uneven surface such as a nonwoven fabric is used as the porous substrate 1, the clay mineral layer 2 does not need to be a uniform layer and may be scattered on the substrate surface. Similarly, the photocatalyst layer 3 does not need to be a uniform layer and may be scattered on the substrate surface. In addition, when the porous substrate 1 absorbs clay minerals, the clay mineral layer 2 may be soaked into the substrate.

The surface-treated part 4 may have a region rich in clay minerals including smectite, a region rich in photocatalyst, and a region where both clay minerals and photocatalyst are mixed. It is the photocatalyst exposed on the surface-treated part 4 that exhibits catalytic activity.
Examples of the porous substrate that can be used include organic substrates such as cloth products, nonwoven fabrics, woven fabrics, resin films, and resin sheets, as well as organic substrates containing paints or dyes, pigments, binders, glues, oils, and the like that contain organic substances, and products that use at least one of these.
The amount of smectite used relative to the porous substrate can be 1.0 to 6.0 g/m ² in terms of solid content. If it exceeds 6.0 g/m ² , the texture and flexibility of the substrate will be lost, and the photocatalyst particles fixed thereon will be easily removed. If it is less than 1.0 g/m ² , the coating will be non-uniform and the effect will tend to be insufficient. However, this will vary depending on the basis weight, surface area, and manufacturing history of the porous substrate, and an appropriate range will be determined depending on the porous substrate.

The clay mineral layer 2 can be formed, for example, by applying a coating liquid containing smectite using a coating method such as dip coating, gravure coating, spin coating, bar coating, or rotary screen coating. For example, when the coating is applied to both sides of the porous substrate, such as by dip coating, it is possible to prevent gas emission from the back side of the organic substrate, for example, when the porous substrate is an organic substrate and the photocatalyst product is stored in a roll or stack. It is also possible to prevent the photocatalyst and the organic substrate from coming into contact and reacting with each other.

The photocatalyst used in the embodiment includes at least one metal oxide such as titanium oxide, zinc oxide, tungsten oxide, niobium oxide, and tin oxide. In addition, at least one of zirconium oxide, platinum, ruthenium, and copper can be added to the photocatalyst.

The amount of photocatalyst used relative to the porous substrate can be 0.2 to 2.0 g/m ² in terms of solid content. If it exceeds 2.0 g/m ² , problems such as changes in color tone and particles becoming easily removed can occur, and if it is less than 0.2 g/m ² , the catalytic action tends to be insufficient, but this varies depending on the basis weight, surface area, manufacturing history, etc. of the porous substrate, and an appropriate range is determined depending on the porous substrate.
The photocatalyst layer 3 can be formed, for example, by applying a slurry containing a photocatalyst using a coating method such as dip coating, gravure coating, spin coating, bar coating, or rotary screen coating.

The surface treatment may further include at least one of ammonium zirconium carbonate or adipic dihydrazide.
Ammonium zirconium carbonate is considered to be used as a crosslinking agent for crosslinking organic matter contained in a porous substrate. Ammonium zirconium carbonate is reacted with carboxyl groups or hydroxyl groups of water-soluble polymers in an organic substrate such as a nonwoven fabric to insolubilize (fix) the porous substrate, thereby preventing unnecessary gas emission or bleeding. According to an embodiment, by further including ammonium zirconium carbonate in the surface treatment portion, a photocatalyst product having better catalytic action on the surrounding atmosphere can be obtained.

The amount of ammonium zirconium carbonate used relative to the porous substrate can be 0.1 to 10.0 g/ ^m2 in terms of solids in terms of _ZrO2 . If it exceeds 10.0 g/ ^m2 , the substrate loses flexibility, and if it is less than 0.1 g/ ^m2 , immobilization tends to be insufficient, but this varies depending on the basis weight, surface area, manufacturing history, etc. of the porous substrate, and the preferred range is not limited.
In this case, the term " _ZrO2 conversion" refers to the process of first weighing the ammonium zirconium carbonate solution, completely evaporating it to dryness, dividing the evaporated and dried weight by the molecular weight of (NH4) ₂ [Zr(CO3) ₂ (OH) ₂ ] (281.33), and multiplying it by the molecular weight of _ZrO2 (123.22) to obtain the weight conversion value of the evaporated and dried ammonium zirconium carbonate to _ZrO2 . Using this weight conversion value as the weight of the solid content, the adhesion amount (solid content amount) per unit area can be calculated.

Adipic acid dihydrazide is used as an adsorbent for adsorbing harmful organic molecules such as formaldehyde. According to the embodiment, by using adipic acid dihydrazide in the surface treatment portion, a photocatalyst product having a better catalytic action on the surrounding atmosphere can be obtained.
The amount of adipic acid dihydrazide used relative to the porous substrate can be 0.5 to 15.0 g/m ² in terms of solid content. If it exceeds 15.0 g/m ² , it may cause the generation of powdery matter, and if it is less than 0.1 g/m ² , it tends to be in a state where sufficient effects cannot be obtained, but this varies depending on the basis weight, surface area, and manufacturing history of the porous substrate, and the preferred range is not limited.

2 to 4 show model diagrams showing other configurations of the photocatalyst product according to the first embodiment.
When ammonium zirconium carbonate is used, for example, as shown in Fig. 2, a crosslinker layer 5 containing ammonium zirconium carbonate can be formed before forming a clay mineral layer 2 on a porous substrate 1. The obtained photocatalyst product 20 includes a crosslinker layer 5, a clay mineral layer 2, and a photocatalyst layer 3, which are formed in this order on the porous substrate 1, as a surface treatment portion 4-1.
When the porous substrate 1 absorbs a crosslinking agent or a clay mineral, the crosslinking agent layer 5 and the clay mineral layer 2 may permeate the porous substrate.

When adipic acid dihydrazide is used, for example, as shown in Fig. 3, an adsorbent layer 6 containing adipic acid dihydrazide can be formed before forming a clay mineral layer on a porous substrate. The obtained photocatalyst product 30 includes, as a surface treatment portion 4-2, an adsorbent layer 6, a clay mineral layer 2, and a photocatalyst layer 3, which are formed in this order on a porous substrate 1. In addition, when the porous substrate 1 absorbs an adsorbent or a clay mineral, the adsorbent layer 6 and the clay mineral layer 2 may be soaked into the porous substrate.
When both the crosslinker layer and the adsorbent layer are applied, for example, as shown in FIG. 4, the crosslinker layer 5 and the adsorbent layer 6 can be formed in this order, or the adsorbent layer 6 and the crosslinker layer 5 can be formed in this order, before forming the clay mineral layer on the porous substrate 1. The obtained photocatalyst product 40 has the crosslinker layer 5, the adsorbent layer 6, the clay mineral layer 2, and the photocatalyst layer 3 laminated in this order on the porous substrate 1 as the surface treatment portion 4-3. In addition, when the porous substrate 1 absorbs the crosslinker, the adsorbent, or the clay mineral, the crosslinker layer 5, the adsorbent layer 6, and the clay mineral layer 2 may be soaked into the porous substrate.

The crosslinking agent layer can be provided closer to the porous substrate than the adsorbent layer in order to react with the carboxyl groups and hydroxyl groups of the water-soluble polymer in the porous substrate. By further including ammonium zirconium carbonate and adipic dihydrazide, a photocatalyst product with even better catalytic action on the surrounding atmosphere can be obtained. In addition, if the crosslinking reaction of the crosslinking agent layer 5 makes it difficult for the adsorbent layer 6 to be impregnated into the porous substrate, the adsorbent layer 6 and the crosslinking agent layer 5 can be formed in that order.

The crosslinker layer and the adsorbent layer can be formed by applying a coating liquid containing a crosslinker and a coating liquid containing an adsorbent, respectively, using a coating method such as dip coating, gravure coating, spin coating, bar coating, or spray coating. For example, when applied to both sides of the porous substrate as in dip coating, gas emission from the back side of the organic substrate can be suppressed when, for example, the porous substrate is an organic substrate and the photocatalyst product is stored in a roll or stack. In addition, reaction between the photocatalyst and the organic substrate upon contact can be suppressed.

FIG. 5 shows a model diagram showing the configuration of a photocatalyst product according to the second embodiment.
The photocatalyst product 50 according to the second embodiment is a porous substrate 1, a crosslinking agent layer 5, and a photocatalyst layer 3 containing tungsten oxide, which are laminated in this order as a surface treatment portion 4-4 provided on the porous substrate 1. When a substrate having an uneven surface such as a nonwoven fabric is used as the porous substrate 1, the crosslinking agent layer 5 does not need to be a uniform layer, and may be scattered on the substrate surface. Similarly, the photocatalyst layer 3 does not need to be a uniform layer, and may be scattered on the substrate surface. In addition, when the porous substrate absorbs the crosslinking agent, the crosslinking agent layer 5 may be soaked into the porous substrate.
The surface-treated part 4 may have a region rich in ammonium zirconium carbonate, a region rich in photocatalyst, and a region where both ammonium zirconium carbonate and photocatalyst are mixed. It is the photocatalyst exposed on the surface-treated part 4 that exhibits catalytic activity.

According to the second embodiment, when a crosslinking agent containing ammonium zirconium carbonate is used, the carboxyl groups and hydroxyl groups of the water-soluble polymer in the porous substrate, for example, the organic substrate, are reacted with ammonium zirconium carbonate to insolubilize it, thereby preventing unnecessary gas emission and bleeding from the porous substrate. In this way, by preventing the photocatalyst from reacting with the porous substrate, a photocatalyst product with good catalytic action in the surrounding atmosphere can be obtained.

The components used in the second embodiment, such as the porous substrate, the surface treatment portion, the crosslinking agent layer, and the photocatalyst layer containing tungsten oxide, are the same as those used in the first embodiment. The amounts of ammonium zirconium carbonate and the photocatalyst layer used relative to the porous substrate are the same as those in the first embodiment.

The photocatalyst product according to the third embodiment includes a porous substrate and a surface treatment section provided on the porous substrate, and the surface treatment section includes a clay mineral including smectite, and a photocatalyst containing tungsten oxide. Furthermore, this photocatalyst product has a chamber volume of 0.5 L, and is irradiated with light from a white fluorescent lamp FL20SW, cuts UV light of 380 nm or less with a Clarex UV cut filter N-169 (Nitto Resin Industry), and is capable of reducing acetaldehyde at a concentration of 10 ppm by 60% or more in 2 hours under conditions of room temperature, normal pressure, and humidity of 20%.

According to the third embodiment, a photocatalyst product having good catalytic action on the surrounding atmosphere can be obtained.

The porous substrate and the surface treatment portion used in the third embodiment are the same as those used in the first embodiment. The amount of the photocatalyst layer and the like used in the porous substrate is the same as that in the first embodiment.
The photocatalyst products according to the embodiments can be prepared by applying a coating liquid containing a photocatalyst, adipic acid dihydrazide, ammonium zirconium carbonate, or a clay mineral containing a member such as smectite to a porous substrate. The state of the member that is fixed to the porous substrate by the application of the coating liquid is affected by the material of the porous substrate. For example, when the porous substrate is a resin film or a resin sheet, the coating liquid is unlikely to penetrate, and the member in the coating liquid can be fixed to cover the surface of the porous substrate. On the other hand, when the porous substrate is a cloth product, a nonwoven fabric, or a woven fabric, the coating liquid is likely to penetrate, and the member in the coating liquid can be fixed to cover each fiber that constitutes the porous substrate. For this reason, in the manufacturing process of the photocatalyst product according to the embodiments, the concentration and coating amount of the coating liquid can be adjusted for each porous substrate used, taking into consideration the ease of penetration of the coating liquid.

As a measure of the ease with which a coating liquid penetrates into a porous substrate, the maximum water absorption amount that the porous substrate can absorb pure water per unit area can be measured in advance for the porous substrate to be used. At this time, the amount of each coating liquid adhering to the porous substrate (solid content) FW (g/ ^m2 ) can be expressed by the following formula (1).
F _W =K/100×W _A ×C/100×(D/D ₀ )...(1)
FW: amount of adhered solids (g/m ² ) K: any value greater than 0 and equal to or less than 100 _WA : maximum amount of water absorption capable of absorbing pure water (g/m ² )
C: Solid content concentration of the coating liquid (% by weight)
D: Specific gravity of coating liquid (g/cm ³ )
D ₀ : Specific gravity of water (g/cm ³ )
In the formula, W _A is the maximum water absorption amount (g/m ² ) that the porous substrate can absorb pure water per unit area, K is an arbitrary value greater than 0 and less than 100 selected depending on the coating method and coating state of the coating liquid, C is the solids concentration (wt %) of the coating liquid, D is the specific gravity of the coating liquid (g/cm ³ ), and D ₀ is the specific gravity of water (g/cm ³ ).

The solid content concentration C (weight %) of each coating liquid varies depending on the materials used in the coating liquid. In the case of smectite, it is 0 to 5 weight %. If the solid content concentration C of a coating liquid containing smectite exceeds 5 weight %, the viscosity increases and water dispersion tends to become difficult, so it can be set to 5 weight % or less. In the case of ammonium zirconium carbonate, it is 0 to 20 weight % in terms of _ZrO2 . If the solid content concentration C of a coating liquid containing ammonium zirconium carbonate (AZC) exceeds 20 weight % ( _ZrO2 equivalent), the ammonia odor becomes strong and the working environment tends to deteriorate, so it can be set to 20 weight % or less. In the case of adipic acid dihydrazide, it can be set to 0 to 11 weight %. Since the solubility of adipic acid dihydrazide (ADH) in water is 11 weight % at 30 ° C, the solid content concentration C of a coating liquid containing adipic acid dihydrazide (ADH) can be set to 11 weight % or less.
The solids concentration C can be preferably 1 to 3% by weight in the case of smectite, 0.1 to 10% by weight in terms of _ZrO2 in the case of ammonium zirconium carbonate, and 0.1 to 8% by weight in the case of adipic acid dihydrazide.

The following provides examples and explains the embodiments in detail.

Example 1
Preparation of clay mineral coating solution 1
Smectite powder was added to pure water stirred with a stirrer so that the concentration was 2.8% by weight, and the mixture was stirred for 5 minutes, then treated with a homogenizer for 15 minutes and left for 24 hours. This was then stirred again with a stirrer to make it homogenous, and a slurry was obtained as clay mineral layer coating liquid 1.

Preparation of photocatalyst coating solution 1
A slurry containing 10 wt% _WO3 and 10 wt% _TiO2 was prepared and diluted with pure water to a total solids content of 2.5 wt%.

Sample Preparation The maximum water absorption capacity of a nonwoven wallpaper cut to a size of 50 x 100 mm was measured and found to be 0.964 g. The maximum water absorption capacity per ^m2 , WA, was estimated to be 192.8 g/ ^m2 .
Clay mineral coating solution 1 was applied to this nonwoven wallpaper by dip coating at 199 g/ ^m2 (K was 100, and the specific gravity D of the coating solution was 1.03 g/ ^cm3 ), and dried at 150°C for 5 minutes to fix 5.6 g/ ^m2 of smectite to the nonwoven wallpaper substrate.
Furthermore, photocatalyst coating solution 1 containing 1.25 wt% _WO3 and 1.25 wt% _TiO2 was applied by dip coating at 40 g/ ^m2 , and dried at 150°C for 5 minutes to fix the photocatalyst at 1.0 g/ ^m2 , thereby obtaining a nonwoven wallpaper as a photocatalyst product.
The nonwoven wallpaper thus produced was pretreated for 24 hours with an ultraviolet lamp FL20SBL adjusted to 20 W/m ² to prepare a sample. In addition, a sample that was not pretreated with ultraviolet light was also prepared.

Test method
In the acetaldehyde gas removal test, a sample was placed in a 5L volume chamber, and after pre-ventilation and adjustment to 25°C and humidity 20%, acetaldehyde gas was injected into the chamber with a syringe so that the concentration was 10 ppm. In the removal test, an ultraviolet sharp cut filter (Kurarex UV cut filter N-169) was sandwiched between the lamp and the chamber, and light was irradiated on the sample surface at 6000 lx using a white fluorescent lamp FL20SW while cutting UV light of 380 nm or less, and the concentration of acetaldehyde gas was measured for 2 hours using a photoacoustic multi-gas monitor INNOVA1412i (manufactured by LumaSense Technologies).

FIG. 6 is a graph showing the catalytic action of the photocatalyst product according to the embodiment, showing the relationship between the light irradiation time and the residual rate of acetaldehyde.
FIG. 7 is a graph showing the catalytic action of another sample of the photocatalyst product according to the embodiment, showing the relationship between the light irradiation time and the residual rate of acetaldehyde.
The results of Example 1 are shown as graph 101 in FIG.
Similarly, a test for removing acetaldehyde gas was carried out on a sample that was not pretreated with ultraviolet light, and the results are shown as graph 506 in FIG.
6 and 7, when smectite and photocatalyst are applied to the surface treatment, the acetaldehyde gas residual rate in the sample pretreated with ultraviolet light was 10% or less in 2 hours, indicating good catalytic action. However, in the sample not pretreated with ultraviolet light, the acetaldehyde gas residual rate was 70% or more in 2 hours, indicating insufficient catalytic action.

Example 2
Preparation of crosslinker coating solution 1
The crosslinking agent coating solution was prepared by diluting a 19% aqueous solution of ammonium zirconium carbonate (calculated as _ZrO2) with pure water to 1.9% by weight and stirring with a stirrer.
Preparation of clay mineral coating solution 1
In the same manner as in Example 1, a slurry of clay mineral layer coating liquid 1 was obtained.
Preparation of photocatalyst coating solution 1
In the same manner as in Example 1, a slurry of photocatalyst coating liquid 1 was obtained.

Sample Preparation The maximum water absorption capacity of a nonwoven wallpaper cut to a size of 50 x 100 mm was measured and found to be 0.964 g. The maximum water absorption capacity per ^m2 , WA, was estimated to be 192.8 g/ ^m2 .
Crosslinking agent coating solution 1 was applied to this nonwoven wallpaper by dip coating at 199 g/ ^m2 (K was 100, and the specific gravity D of the coating solution was 1.033 g/ ^cm3 ) and dried at 150°C for 5 minutes to fix ammonium zirconium carbonate. In this way, 3.8 g/ ^m2 of ammonium zirconium carbonate solids ( _ZrO2 equivalent) was fixed to the nonwoven wallpaper substrate.

Next, the same clay mineral coating solution 1 as in Example 1 was applied by dip coating at 199 g/ ^m2 (K was 100 and the liquid specific gravity D was 1.04 g/ ^cm3 ) and dried at 150°C for 5 minutes to fix 5.6 g/ ^m2 of smectite to the nonwoven fabric wallpaper substrate.

Furthermore, photocatalyst coating solution 1 containing 1.25 wt% _WO3 and 1.25 wt% _TiO2 was applied by dip coating at 40 g/ ^m2 , and dried at 150°C for 5 minutes to fix the photocatalyst at 1.0 g/ ^m2 , thereby obtaining a nonwoven wallpaper as a photocatalyst product.
The nonwoven wallpaper thus produced was pretreated for 24 hours with an ultraviolet lamp FL20SBL adjusted to 20 W/m ² to prepare a sample. A sample that was not pretreated was also prepared.

Test method
In the same manner as in Example 1, the concentration of acetaldehyde gas was measured for two hours.
The results obtained are shown as graph 102 in FIG.
Similarly, a test for removing acetaldehyde gas was carried out on a sample that was not pretreated with ultraviolet light, and the results are shown as graph 503 in FIG.
6 and 7, when smectite, a photocatalyst, and a crosslinking agent are used in the surface treatment, the sample that was pretreated with ultraviolet light had an acetaldehyde gas residual rate of 10% or less in 2 hours, demonstrating good catalytic action.The sample that was not pretreated with ultraviolet light had an acetaldehyde gas residual rate of 20% or less in 2 hours, confirming the catalytic effect.

Example 3
Preparation of adsorbent coating solution 1
Adsorbent coating solution 1 was prepared by adding adipic acid dihydrazide powder to pure water and stirring with a stirrer to give a concentration of 0.4% by weight.
Preparation of clay mineral coating solution 1
In the same manner as in Example 1, a slurry of clay mineral layer coating liquid 1 was obtained.
Preparation of photocatalyst coating solution 1
In the same manner as in Example 1, a slurry of photocatalyst coating liquid 1 was obtained.

Sample preparation
The maximum amount of pure water absorbed by a nonwoven wallpaper cut to a size of 50 x 100 mm was measured and found to be 0.964 g. The maximum amount of water absorbed per ^m2 , WA, was estimated to be 192.8 g/ ^m2 .
The nonwoven wallpaper was coated with 192.8 g/ ^m2 of adsorbent coating solution 1 by dip coating (K was 100, and the specific gravity D of the coating solution was 1.000 g/ ^cm3 ) and dried at 150°C for 5 minutes to fix the adipic acid dihydrazide. In this way, 0.8 g/ ^m2 of adipic acid dihydrazide was fixed to the nonwoven wallpaper substrate as a solid content.

Next, the same clay mineral coating solution 1 as in Example 1 was applied by dip coating at 199 g/ ^m2 (ratio K was 100, and specific gravity D of the coating solution was 1.04 g/ ^cm3 ), and dried at 150°C for 5 minutes to fix 5.6 g/ ^m2 of smectite to the nonwoven fabric wallpaper substrate.
Furthermore, photocatalyst coating solution 1 containing 1.25 wt% _WO3 and 1.25 wt% _TiO2 was applied by dip coating at 40 g/ ^m2 , and dried at 150°C for 5 minutes to fix the photocatalyst at 1.0 g/ ^m2 , thereby obtaining a nonwoven wallpaper as a photocatalyst product.
The nonwoven wallpaper thus produced was pretreated for 24 hours with an ultraviolet lamp FL20SBL adjusted to 20 W/m ² to prepare a sample. A sample that was not pretreated was also prepared.

Test method
In the same manner as in Example 1, the concentration of acetaldehyde gas was measured for two hours.
The results obtained are shown as graph 103 in FIG.
Similarly, a test for removing acetaldehyde gas was carried out on a sample that was not pretreated with ultraviolet light, and the results are shown as graph 502 in FIG.
6 and 7, when smectite, photocatalyst, and adsorbent are used in the surface treatment, the acetaldehyde gas residual rate was 10% or less in 2 hours in the sample that was pretreated with ultraviolet light, demonstrating good catalytic action. Even in the sample that was not pretreated with ultraviolet light, the acetaldehyde gas residual rate was 10% or less in 2 hours, confirming sufficient catalytic effect.

Example 4
Preparation of adsorbent coating solution 1
An adsorbent coating solution 1 was prepared in the same manner as in Example 3.
Preparation of crosslinker coating solution 1
A crosslinking agent coating solution was prepared in the same manner as in Example 2.
Preparation of clay mineral coating solution 1
In the same manner as in Example 1, a slurry of clay mineral layer coating liquid 1 was obtained.
Preparation of photocatalyst coating solution 1
In the same manner as in Example 1, a slurry of photocatalyst coating liquid 1 was obtained.

Sample preparation
The maximum amount of pure water absorbed by a nonwoven wallpaper cut to a size of 50 x 100 mm was measured and found to be 0.964 g. The maximum amount of water absorbed per ^m2 , WA, was estimated to be 192.8 g/ ^m2 .
The nonwoven wallpaper was coated with 192.8 g/ ^m2 of adsorbent coating solution 1 (K was 100, and the specific gravity D of the coating solution was 1.000 g/ ^cm3 ) by dip coating, and then dried at 150°C for 5 minutes to fix the adipic acid dihydrazide. In this way, 0.8 g/ ^m2 of adipic acid dihydrazide was fixed to the nonwoven wallpaper substrate as a solid content.

Next, 199 g/ ^m2 of crosslinking agent coating solution 1 (K was 100, and the specific gravity D of the coating solution was 1.033 g/ ^cm3 ) was applied to this nonwoven wallpaper by dip coating, and dried for 5 minutes at 150°C to fix ammonium zirconium carbonate. In this way, 3.8 g/ ^m2 of ammonium zirconium carbonate solid content ( _ZrO2 equivalent) and adipic acid dihydrazide solid content were fixed to the nonwoven wallpaper substrate.
Next, 199 g/ ^m2 of clay mineral coating solution 1 similar to that in Example 1 was applied by dip coating (ratio K was 100, and specific gravity D of the coating solution was 1.04 g/ ^cm3 ), and dried at 150°C for 5 minutes to adhere 5.6 g/ ^m2 of smectite to the nonwoven fabric wallpaper substrate.

Furthermore, photocatalyst coating solution 1 containing 1.25 wt% _WO3 and 1.25 wt% _TiO2 was applied by dip coating at 40 g/ ^m2 , and dried at 150°C for 5 minutes to fix the photocatalyst at 1.0 g/ ^m2 , thereby obtaining a nonwoven wallpaper as a photocatalyst product.
The nonwoven wallpaper thus produced was pretreated for 24 hours with an ultraviolet lamp FL20SBL adjusted to 20 W/m ² to prepare a sample. A sample that was not pretreated was also prepared.

Test method
In the same manner as in Example 1, the concentration of acetaldehyde gas was measured for two hours.
The results obtained are shown as graph 104 in FIG.
Similarly, a test for removing acetaldehyde gas was carried out on a sample that was not pretreated with ultraviolet light, and the results are shown as graph 504 in FIG.
6 and 7, when smectite, a photocatalyst, a crosslinking agent, and an adsorbent were used in the surface treatment, the acetaldehyde gas residual rate was 10% or less in 2 hours in the sample that was pretreated with ultraviolet light. In the sample that was not pretreated with ultraviolet light, the acetaldehyde gas residual rate was 10% or less in 2 hours, confirming that there was a good catalytic effect.

Example 5
Preparation of crosslinker coating solution 1
A crosslinking agent coating solution was prepared in the same manner as in Example 2.
Preparation of photocatalyst coating solution 1
In the same manner as in Example 1, a slurry of photocatalyst coating liquid 1 was obtained.

Sample preparation
The maximum amount of pure water absorbed by a nonwoven wallpaper cut to a size of 50 x 100 mm was measured and found to be 0.964 g. The maximum amount of water absorbed per ^m2 , WA, was estimated to be 192.8 g/ ^m2 .
Crosslinking agent coating solution 1 was applied to this nonwoven wallpaper by dip coating at 199 g/ ^m2 (K was 100, and the specific gravity D of the coating solution was 1.033 g/ ^cm3 ) and dried at 150°C for 5 minutes to fix ammonium zirconium carbonate. In this way, 3.8 g/ ^m2 of ammonium zirconium carbonate solids ( _ZrO2 equivalent) was fixed to the nonwoven wallpaper substrate.

Next, photocatalyst coating solution 1 containing 1.25 wt% _WO3 and 1.25 wt% _TiO2 was applied by dip coating at 40 g/ ^m2 , and dried at 150°C for 5 minutes to fix the photocatalyst at 1.0 g/ ^m2 , thereby obtaining a nonwoven wallpaper as a photocatalyst product.
The produced nonwoven wallpaper was pretreated for 24 hours with an ultraviolet lamp FL20SBL adjusted to 20 W/ ^m2 , and used as a sample.

Test method
In the same manner as in Example 1, the concentration of acetaldehyde gas was measured for two hours.
The results obtained are shown as graph 105 in FIG.

Example 6
Preparation of mixed coating solution 1 of crosslinker and adsorbent
The solutions were prepared by diluting a 19% aqueous solution of ammonium zirconium carbonate with pure water, adding adipic acid dihydrazide powder, and stirring with a stirrer to give concentrations of 1.9% by weight and 0.4% by weight, respectively.
Preparation of clay mineral coating solution 1
In the same manner as in Example 1, a slurry of clay mineral layer coating liquid 1 was obtained.
Preparation of photocatalyst coating solution 1
In the same manner as in Example 1, a slurry of photocatalyst coating liquid 1 was obtained.

Sample preparation
A nonwoven wallpaper was prepared as the substrate. An SEM photograph of the porous substrate used is shown in Figure 11. Figure 11 shows the surface of the nonwoven wallpaper substrate. As shown in the figure, a dye containing filler (scale-like pieces) is applied for decoration to the nonwoven substrate, which contains polyester fibers in addition to natural fibers.
The maximum amount of pure water absorbed by a nonwoven wallpaper cut to a size of 50 x 100 mm was measured and found to be 0.964 g. The maximum amount of water absorbed per ^m2 , WA, was estimated to be 192.8 g/ ^m2 .

The nonwoven wallpaper was coated with 196.1 g/ ^m2 of mixed coating solution 1 of crosslinker and adsorbent by dip coating (K was 100, and specific gravity D of the coating solution was 1.017 g/ ^cm3 ) and dried at 150°C for 5 minutes to fix ammonium zirconium carbonate and adipic acid dihydrazide. In this way, 3.7 g/ ^m2 of ammonium zirconium carbonate solid content ( _ZrO2 equivalent) and 0.8 g/ ^m2 of adipic acid dihydrazide solid content were fixed to the nonwoven wallpaper substrate.

Next, the same clay mineral coating liquid 1 as in Example 1 was applied by dip coating at 199 g/ ^m2 (ratio K was 100, and liquid specific gravity D was 1.04 g/ ^cm3 ), and dried at 150°C for 5 minutes to fix 5.6 g/ ^m2 of smectite to the nonwoven fabric wallpaper substrate.
Furthermore, photocatalyst coating solution 1 containing 1.25 wt% _WO3 and 1.25 wt% _TiO2 was applied by dip coating at 40 g/ ^m2 , and dried at 150°C for 5 minutes to fix the photocatalyst at 1.0 g/ ^m2 , thereby obtaining a nonwoven wallpaper as a photocatalyst product.

An SEM photograph of the surface of the obtained photocatalyst product observed with an electron microscope is shown in Fig. 12. As shown in the figure, in this photocatalyst product, the crosslinking agent, the adsorbent, and the photocatalyst soaked in from the surface of the porous substrate are provided on the natural fibers and the polyester fibers, respectively.
The nonwoven wallpaper thus produced was pretreated for 24 hours with an ultraviolet lamp FL20SBL adjusted to 20 W/m ² to prepare a sample. A sample that was not pretreated was also prepared.

Test method 1 (initial value)
In the same manner as in Example 1, the concentration of acetaldehyde gas was measured for two hours.
The results obtained are shown as graph 106 in FIG.
Similarly, a test for removing acetaldehyde gas was carried out on a sample that was not pretreated with ultraviolet light, and the results are shown as graph 501 in FIG.
6 and 7, when smectite, a photocatalyst, a crosslinking agent, and an adsorbent were used in the surface treatment, the acetaldehyde gas residual rate was 10% or less in 2 hours in the sample that was pretreated with ultraviolet light. In the sample that was not pretreated with ultraviolet light, the acetaldehyde gas residual rate was 10% or less in 2 hours, confirming that there was a good catalytic effect.

Test method 2
As a formaldehyde removal test, the concentration of formaldehyde gas was measured for 48 hours for samples that had been subjected to ultraviolet light pretreatment in the same manner as in Example 1, except that formaldehyde gas was injected instead of acetaldehyde gas and a 5 L gas bag was used.
As a result, the residual formaldehyde rate after 48 hours was less than 10%, confirming a good catalytic effect.

Test method 3
As a toluene removal test, the concentration of toluene gas was measured for 48 hours on a sample that had been subjected to ultraviolet light pretreatment in the same manner as in Example 1, except that toluene gas was injected instead of acetaldehyde gas and a 5 L gas bag was used.
As a result, the toluene remaining rate after 48 hours was 59%. Regarding the decomposition of toluene, the remaining rate was 65% or less, which indicates the presence of a catalytic effect.

Comparative Example 1-1
Preparation of photocatalyst coating solution 1
In the same manner as in Example 1, a slurry of photocatalyst coating liquid 1 was obtained.
Sample preparation
A nonwoven wallpaper cut to 50 x 100 mm is coated with the photocatalyst coating solution 1 by dip coating so that the solid content is 1.0 g/ ^m2 , and dried for 5 minutes in a drying oven at 120 ° C. The nonwoven wallpaper thus prepared is pretreated for 24 hours with an ultraviolet lamp FL20SBL adjusted to 20 W/ ^m2 to prepare a sample. A sample without pretreatment was also prepared separately.

Test method 1
In the same manner as in Example 1, the concentration of acetaldehyde gas was measured for two hours.
The results obtained are shown as graph 107 in FIG.
Similarly, a test for removing acetaldehyde gas was carried out on a sample that was not pretreated with ultraviolet light, and the results are shown as graph 505 in FIG.
6 and 7, when only a photocatalyst is applied to the surface treatment portion, the acetaldehyde residual rate in the sample that was pretreated with ultraviolet light was about 25% after 2 hours, whereas the acetaldehyde gas residual rate in the sample that was not pretreated with ultraviolet light was about 80% after 2 hours, confirming that a sufficient catalytic effect was not obtained.

Test method 2
The formaldehyde removal test was carried out for 48 hours in the same manner as in Test Method 2 of Example 6.

As a result, the residual formaldehyde rate after 48 hours increased to more than 250%.
The increase in formaldehyde is believed to be due to the organic substrate. Simply applying a photocatalyst layer to the organic substrate is not enough to suppress the formaldehyde generated from the organic substrate, and therefore it is believed that sufficient catalytic action cannot be obtained.

Test method 3
The toluene removal test was carried out for 48 hours in the same manner as in Test Method 3 of Example 6.
As a result, the remaining rate of toluene after 48 hours was 95%.
It is believed that toluene was hardly decomposed. It is believed that sufficient catalytic action cannot be obtained because toluene cannot be reduced by simply applying a photocatalyst layer on an organic substrate.

Comparative Example 2
Preparation of photocatalyst coating solution 1
In the same manner as in Example 1, a slurry of photocatalyst coating liquid 1 was obtained.
Sample preparation
A sample was prepared in the same manner as in Comparative Example 1, except that a non-porous substrate, 50×100 mm glass, was used instead of the non-woven wallpaper cut to 50×100 mm. A sample that was not pretreated was also prepared.

Test Method: In the same manner as in Example 1, the concentration of acetaldehyde gas was measured for two hours.
The results obtained are shown as graph 108 in FIG.
Similarly, a test for removing acetaldehyde gas was carried out on a sample that was not pretreated with ultraviolet light, and the results are shown as graph 507 in FIG.
As can be seen from Figures 6 and 7, when only a photocatalyst is applied to the surface treatment area, the acetaldehyde gas residual rate is about 10% after 2 hours for both samples that have been pretreated with ultraviolet light and samples that have not been pretreated with ultraviolet light, and for glass substrates, sufficient catalytic effect can be obtained even with only the photocatalyst coating liquid 1.

Tables 1-1 and 1-2 show the coating solution concentration and adhesion amount in the surface treatment section, and the evaluation of the concentration measurement of acetaldehyde gas and other gases for Examples 1 to 6 and Comparative Examples 1 and 2. In the tables, the adhesion amount (g/m ² ) is shown in parentheses under the coating solution concentration (wt %). The evaluation was performed as follows: if the residual rate of acetaldehyde gas after 2 hours was 20% or less, it was marked as ○, and if it exceeded 20%, it was marked as ×. Furthermore, if the residual rate of formaldehyde gas after 48 hours was 20% or less, it was marked as ○, and if it exceeded 20%, it was marked as ×. In the case of toluene gas, if the residual rate after 48 hours was 60% or less, it was marked as ○. If it exceeded 60%, it was marked as ×.

As shown in Table 1-1, the residual rate of acetaldehyde gas in the photocatalyst products of Examples 1 to 6 was 20% or less after 2 hours, and it was found that the catalytic action in the surrounding atmosphere was good even when an organic substrate was used. In addition, for samples that were not pretreated with ultraviolet light, good catalytic action was confirmed when smectite, photocatalyst, crosslinking agent, and adsorbent were used in the surface treatment area, as shown in Examples 4 and 6. Also, sufficient catalytic action was confirmed when smectite, photocatalyst, and either a crosslinking agent or an adsorbent were used in the surface treatment area, as shown in Examples 2 and 3. However, sufficient catalytic action was not confirmed when smectite, photocatalyst, and crosslinking agent were used in the surface treatment area, as shown in Example 1.

Figure 8 is a graph showing the catalytic action of a comparative photocatalyst product, showing the relationship between light exposure time and the residual rate of acetaldehyde.

Comparative Example 1 is an example of an organic substrate and is shown as graph 107 in FIG.
As shown in Fig. 8, when the photocatalyst is applied directly onto the organic substrate, a large amount of harmful organic molecules from the organic substrate are adsorbed and decomposed, so that the apparent catalytic action on the surrounding atmosphere is reduced, as shown in graph 107. In contrast, even when the photocatalyst is applied directly onto the glass substrate, harmful organic molecules are not generated from the glass substrate, as shown in graph 108, so the catalytic action on the surrounding atmosphere is not reduced. In addition, since graph 108 is almost the same as in Examples 1 to 6, it is considered that the photocatalyst products of Examples 1 to 6 can reduce the generation of harmful organic molecules in the organic substrate to the same level as a glass substrate, which does not generate harmful organic molecules.

実施例７
架橋剤と吸着剤の混合塗付液２の調製
１９％炭酸ジルコニウムアンモニウム水溶液を純水で希釈し、アジピン酸ジヒドラジド粉末を添加してスターラーで撹拌して作製した。この時の濃度は、それぞれ３．５重量％、５重量％とした。
粘土鉱物塗付液１の調製
実施例１と同様にして、粘土鉱物層塗付液１のスラリーを得た。
光触媒塗付液１の調製
実施例１と同様にして、光触媒塗付液１のスラリーを得た。

Example 7
Preparation of mixed coating solution 2 of crosslinker and adsorbent
The solutions were prepared by diluting a 19% aqueous solution of ammonium zirconium carbonate with pure water, adding adipic acid dihydrazide powder, and stirring with a stirrer to give concentrations of 3.5% by weight and 5% by weight, respectively.
Preparation of clay mineral coating solution 1
In the same manner as in Example 1, a slurry of clay mineral layer coating liquid 1 was obtained.
Preparation of photocatalyst coating solution 1
In the same manner as in Example 1, a slurry of photocatalyst coating liquid 1 was obtained.

Sample preparation
The maximum amount of pure water that a nonwoven wallpaper cut into a size of 50 x 100 mm could absorb was measured and found to be 0.964 g. The maximum amount of water absorption per m2, WA, was estimated to be 192.8 g/m2.
The mixed coating solution 2 of crosslinker and adsorbent was applied to this nonwoven wallpaper by dip coating at 199.2 g/m2 (K was 100, and the specific gravity D of the coating solution was 1.033 g/cm3), and dried at 150°C for 5 minutes to fix ammonium zirconium carbonate and dihydrazide adipic acid. In this way, 7.0 g/m2 of ammonium zirconium carbonate solid content (ZrO2 equivalent) and 10.0 g/ ^m2 of dihydrazide adipic acid were fixed to the nonwoven wallpaper substrate.

Next, the same clay mineral coating solution 1 as in Example 1 was applied by dip coating at 199 g/m2 (ratio K was 100, and liquid specific gravity D was 1.04 g/cm3) and dried at 150°C for 5 minutes, thereby fixing 5.6 g/ ^m2 of smectite to the nonwoven fabric wallpaper substrate.
Furthermore, photocatalyst coating solution 1 containing 1.25 wt% _WO3 and 1.25 wt% _TiO2 was applied by dip coating at 40 g/ ^m2 , and dried at 150°C for 5 minutes to fix the photocatalyst at 1.0 g/ ^m2 , thereby obtaining a nonwoven wallpaper as a photocatalyst product.

Test method 1 (initial value)
In the same manner as in Example 1, the concentration of acetaldehyde gas was measured for two hours.
FIG. 9 is a graph showing the catalytic action of the photocatalyst product according to the embodiment, showing the relationship between the light irradiation time and the acetaldehyde residual rate.
The results obtained are shown as graph 301 in FIG.
Test method 2 (after 7 days)
The sample with the initial value measured was left on a desk in an office with white fluorescent lights and people coming and going for 7 days as a real space test. The illuminance on the sample surface was about 350 lx, and the lights were turned off at night and on holidays. The acetaldehyde gas removal test was performed under the same conditions as Test Method 1, and the data was taken after leaving the sample in the real space for 7 days.
The results obtained are shown as graph 302 in FIG.
Test method 3 (after 15 days)
The samples that had been subjected to the 7-day real-space storage test were left for a further 8 days under the same conditions as in Test Method 2, and the acetaldehyde gas removal test was carried out under the same conditions as in Test Method 1, and the data after leaving the samples in the real space for 15 days was recorded.

The results obtained are shown as graph 303 in FIG.
Comparative Example 1-2
The same sample as in Comparative Example 1-1 was prepared, and an acetaldehyde gas removal test was carried out in the same manner as in Example 7 at the initial stage, after 7 days, and after 15 days.
FIG. 10 is a graph showing the catalytic action of a comparative photocatalyst product, showing the relationship between the light irradiation time and the residual rate of acetaldehyde.
The initial value is shown in graph 401, the value after 7 days in graph 402, and the value after 15 days in graph 403.

As shown in FIG. 9, in the photocatalyst product of Example 7, the residual rate of acetaldehyde gas was 30% or less after 2 hours even after 7 days or 15 days, and it was found that the catalytic action on the surrounding atmosphere was sufficient and the life characteristics were good.
In contrast, as shown in FIG. 10, in the photocatalyst product of Comparative Example 1, after 7 days and 15 days, the residual rate of acetaldehyde gas exceeded 80% after 2 hours, indicating that the catalytic action against the surrounding atmosphere was reduced and the life characteristics were poor.

Examples 8-1 and 8-2
Preparation of mixed coating solution 3 of crosslinker and adsorbent
A 19% aqueous solution of ammonium zirconium carbonate was diluted with pure water, and adipic acid dihydrazide powder was added and stirred with a stirrer to prepare the solution. The concentrations were 5% by weight ( _ZrO2 equivalent) and 7.5% by weight, respectively.
Preparation of clay mineral coating solution 2
Smectite powder was added to pure water stirred with a stirrer so that the concentration was 4% by weight, and the mixture was stirred for 5 minutes, then treated with a homogenizer for 15 minutes and left for 24 hours. This was then stirred again with a stirrer to make it homogenous, and a slurry was obtained as clay mineral layer coating liquid 2.

Preparation of photocatalyst coating solution 2
A slurry containing 10% by weight of _WO3 in pure water was prepared, and 10% by weight of _TiO2 photocatalyst was added to the weight of the slurry. This was diluted with pure water so that the total solid content was 4.5% by weight to prepare photocatalyst coating liquid 2.

Sample preparation
The maximum water absorption capacity of the nonwoven wallpaper cut into a size of 50 x 100 mm was previously measured and found to be 0.964 g. Therefore, the water absorption capacity WA of the substrate per ^m2 was estimated to be 192.8 g/ ^m2 .
Mixed coating solution 3 was applied to this nonwoven wallpaper by dip coating at 28.9 g/ ^m2 (K was 14.3, and specific gravity D of the coating solution was 1.049 g/ ^cm3 ) and dried at 170°C for 3 minutes to fix ammonium zirconium carbonate and adipic acid dihydrazide. Ammonium zirconium carbonate solid content ( _ZrO2 equivalent) of 1.45 g/ ^m2 and adipic acid dihydrazide solid content of 2.17 g/ ^m2 were fixed to the nonwoven wallpaper substrate.

Next, 62.3 g/m2 of clay mineral coating liquid ² (K was 31, and the specific gravity D of the coating liquid was 1.043 g/ ^cm3 ) was applied with a squeegee and dried at 170°C for 4 minutes to fix the smectite. In this way, 2.5 g/ ^m2 of smectite was fixed to the nonwoven wallpaper.
Furthermore, 26.5 g/m2 of photocatalyst coating liquid ² was applied to the nonwoven wallpaper with a squeegee and dried at 120°C for 3 minutes to fix the photocatalyst at 1.2 g/ ^m2 , thereby producing the nonwoven wallpaper of Example 8-1.

In addition, as Example 8-2, a nonwoven wallpaper was produced by applying 45 g/ ^m2 of the photocatalyst coating liquid 2 with a squeegee. The drying temperature was 120°C, and the drying time was 5 minutes. The amount of photocatalyst at this time was 2.0 g/ ^m2 .
The nonwoven wallpapers of Examples 8-1 and 8-2 were pretreated for 24 hours with an ultraviolet lamp FL20SBL adjusted to 20 W/ ^m2 to obtain samples.

Test method
Acetaldehyde gas removal test
The concentration of acetaldehyde gas was measured for 2 hours in the same manner as in Example 1. In Example 8-1, the residual rate of acetaldehyde gas was 10% or less, and in Example 8-2, it was 5% or less, and it was found that both had good catalytic action.

Black cloth transfer test method
The surface of a nonwoven wallpaper prepared separately in the same manner as the above sample preparation was rubbed with a black wool cloth, and the color transferred to the black cloth was observed. The black cloth was placed on the nonwoven wallpaper placed on a flat plate, and a load of 3 kgf was applied to a circular surface with a diameter of 17 mm from above, and the nonwoven wallpaper and the black cloth were rubbed by moving it for 10 cm. The pressure at this time was 13.2 g/ ^mm2 .

Figure 13 shows a photograph of the black cloth surface illustrating the results of the transfer test of the nonwoven wallpaper of Example 8-1, and Figure 14 shows a photograph of the black cloth surface illustrating the results of the transfer test of the nonwoven wallpaper of Example 8-2.

In Example 8-1, the black cloth was almost unchanged, but in Example 8-2, it turned white. The cause of the white color was confirmed to be a photocatalytic component as a result of checking with a handheld fluorescent X-ray measuring device (Olympus Corporation, product name Handheld Fluorescent X-ray Analyzer DELTA Professional). In this example of a porous substrate, the amount of photocatalyst adhered was appropriate at 1.2 g/m ² , but it was found that the amount of photocatalyst adhered tended to be somewhat excessive at 2.0 g/m ² .

Example 9 and Comparative Example 3
Preparation of crosslinker coating solution 2
A 19 wt% ( _ZrO2 equivalent) aqueous solution of ammonium zirconium carbonate was diluted with pure water to prepare an aqueous solution with a concentration of 0.75 wt% ( _ZrO2 equivalent).
Preparation of photocatalyst coating solution 3
A slurry in which 10 wt% _WO3 was dispersed was diluted with pure water to adjust the solid content to 0.5 wt%.

Sample preparation
The maximum water absorption capacity of the moquette fabric cut into a size of 50 x 100 mm was measured and found to be 7.94 g. Therefore, the base material water absorption capacity WA per ¹ m2 was estimated to be 1588 g/ ^m2 .
Crosslinking agent coating solution 2 was applied to this moquette fabric by dip coating at 200 g/ ^m2 (K was 12.4, and the specific gravity D of the coating solution was 1.013 g/ ^cm3 ), and the fabric was dried at 150°C for 3 minutes to fix ammonium zirconium carbonate. 1.5 g/ ^m2 of ammonium zirconium carbonate was fixed to the moquette fabric as a solid content ( _ZrO2 equivalent).

Next, the photocatalyst coating liquid ³ was applied to the above moquette fabric at 200 g/m2 using a simple gravure tester, and dried at 120 °C for 3 minutes to fix the _WO3 photocatalyst at 1.0 g/ ^m2 , thereby obtaining the moquette fabric of Example 9.
As Comparative Example 3, a moquette fabric was prepared in the same manner as in Example 9, except that the crosslinking agent coating solution 2 was not applied.
The moquette fabrics of Example 9 and Comparative Example 3, and the moquette fabric for Blank that was not treated at all were pretreated for 12 hours with an ultraviolet lamp FL20SBL adjusted to 20 W/ ^m2 to prepare samples.

Acetaldehyde removal test method
In the acetaldehyde gas removal test, a sample was placed in a 1.5 L volume chamber, and after pre-ventilation and adjustment to 25°C and 20% humidity, acetaldehyde gas was injected into the chamber with a syringe so that the concentration was 10 ppm. In the removal test, an ultraviolet sharp cut filter (Kurarex UV cut filter N-169) was sandwiched between the lamp and the chamber, and light was irradiated on the sample surface at 6000 lx using a white fluorescent lamp FL20SW while cutting out UV light of 380 nm or less, and the concentration of acetaldehyde gas was measured using a photoacoustic multi-gas monitor INNOVA1412i (LumaSense
The measurement was performed for 1 hour using a 350 nm NMR spectrometer (manufactured by Sigma-Aldrich Technologies). The results are shown in FIG.

FIG. 15 is a graph showing the relationship between the light irradiation time and the residual rate of acetaldehyde.
In the figure, 501 indicates the results of the blank moquette fabric, 502 indicates the results of Comparative Example 3, and 503 indicates the results of Example 9. As shown in 502, the moquette fabric of Comparative Example 3, which was coated with only the photocatalyst, had an acetaldehyde residual rate of 90% or more, indicating no catalytic action, but as shown in 503, the moquette fabric of Example 9, which was coated with ammonium zirconium carbonate and the photocatalyst, had an acetaldehyde gas residual rate of 50% or less, indicating that treatment with ammonium zirconium carbonate provided good catalytic action.
Tables 1-1 and 1-2 also show the evaluation of the coating liquid concentration and adhesion amount in the surface treatment area and the acetaldehyde gas concentration measurement for Examples 7, 8-1, 8-2, and 9, and Comparative Example 3.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims.
The invention as originally claimed in the present application is set forth below.
[1]
A porous substrate;
A photocatalyst product comprising a surface treatment section provided on the porous substrate, the surface treatment section including a clay mineral including smectite and a photocatalyst containing tungsten oxide.
[2]
The photocatalyst product according to [1], wherein the surface treatment further comprises at least one of ammonium zirconium carbonate or adipic dihydrazide.
[3]
The surface treatment portion includes a clay mineral layer including the clay mineral provided on the porous substrate,
The photocatalyst product according to [1] or [2], further comprising a photocatalyst layer comprising the photocatalyst and provided on the clay mineral layer.
[4]
The photocatalyst product according to [3], further comprising a layer containing ammonium zirconium carbonate or a layer containing adipic dihydrazide between the surface treatment portion and the porous substrate.
[5]
A porous substrate;
A photocatalyst product comprising a surface treatment section provided on the porous substrate, the surface treatment section including a photocatalyst containing ammonium zirconium carbonate and tungsten oxide.
[6]
A porous substrate and a surface treatment portion provided on the porous substrate, the surface treatment portion including a clay mineral including smectite and a photocatalyst including tungsten oxide;
This photocatalyst product reduces acetaldehyde by 60% or more when it is placed in a 0.5 liter chamber containing 10 ppm acetaldehyde and exposed to 6,000 lux of light using a white fluorescent lamp FL20SW while using an ultraviolet filter to block light below 380 nm, and left for 2 hours at room temperature, normal pressure, and humidity of 20%.
[7]
The photocatalyst product according to any one of [1] to [6], wherein the porous substrate is a nonwoven fabric.
[8]
The photocatalyst product according to any one of [1] to [7], wherein the porous substrate is wallpaper.
[9]
The photocatalytic product according to any one of [1] to [6], wherein the porous substrate is a wall cloth.

1...Porous substrate, 2...Clay mineral layer, 3...Photocatalyst layer, 4, 4-1, 4-2, 4-3...Surface treatment section, 5...Crosslinker layer, 6...Adsorbent layer, 10, 20, 30, 40, 50...Photocatalyst product

Claims (4)

A porous substrate;
A surface treatment portion is provided on the porous substrate,
The surface treatment section comprises an ammonium zirconium carbonate layer on the porous substrate, and a photocatalyst layer containing tungsten oxide on the ammonium zirconium carbonate layer. The photocatalytic product according to claim 1, wherein the porous substrate is a nonwoven fabric. The photocatalytic product according to claim 1 or 2, wherein the porous substrate is wallpaper. The photocatalytic product according to any one of claims 1 to 3, wherein the porous substrate is a wall cloth.

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