JP2012025163A - Photocatalyst supporting structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photocatalyst supporting structure including a photocatalyst layer, an adhesive layer and a carrier, wherein the adhesive layer and the photocatalyst layer are provided on the carrier sequentially, and the adhesive layer contains silica combined in a long and thin shape.SOLUTION: A photocatalyst supporting structure includes a photocatalyst layer, an adhesive layer and a carrier, wherein the adhesive layer and the photocatalyst layer are provided on the carrier sequentially, and the adhesive layer contains silica combined in a long and thin shape. Preferably, the adhesive layer contains 0.1-60 wt.% of the silica combined in a long and thin shape.

Description

  The present invention is a structure carrying a photocatalyst used for water purification, deodorization, antifouling, sterilization, wastewater treatment, growth control of algae, various chemical reactions, etc., particularly durability sufficient even in an outdoor environment with excellent transparency. The present invention relates to a photocatalyst carrying structure having an adhesive layer and a coating liquid for forming an adhesive layer.

  Conventionally, there has been known a photocatalyst-supporting structure in which a photocatalyst is supported on a carrier (base material or substrate) for the purpose of antibacterial, antifungal and decomposition of harmful substances by the action of the photocatalyst. Such a photocatalyst-supporting structure is usually produced by forming a photocatalyst layer by applying and curing a photocatalyst layer-forming coating solution containing a photocatalyst component on the surface of a carrier.

  However, when a photocatalyst layer (a film or layer containing a photocatalyst) is formed directly on the carrier, problems such as deterioration of the carrier and discoloration due to the strong oxidizing action of the photocatalyst, and a problem that the photocatalyst layer is peeled off from the carrier occur. There was a fear. Therefore, a photocatalyst structure having a binder layer (hardly decomposable intermediate layer: adhesive layer) between the carrier and the photocatalyst layer is known (Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4). Patent Document 5 and Patent Document 6). Silica sol has been frequently used as such a binder layer.

  However, when such a photocatalyst carrying structure is used outdoors, there has been a problem that the transparency of the binder layer and the photocatalyst layer is deteriorated by being exposed to environmental changes such as temperature and humidity over a long period of time. In particular, in the case of a structure in which the transparency of the carrier and the color and pattern of the carrier are important, deterioration of the transparency of the binder layer and the photocatalyst layer has been a serious problem.

  On the other hand, Patent Document 7 discloses that the elastic modulus of a resin member is improved and the coefficient of thermal expansion is reduced by adding a silica composition in which the surface of fine particle silica such as granular or chain silica is modified to a resin monomer. It is disclosed that it can be made. However, it has not been known that the transparency of the photocatalyst layer for the photocatalyst and the adhesive layer can be maintained for a longer period by using silica bonded in an elongated shape as chain silica or the like.

JP 2005-137777 A JP 2004-351365 A JP-A-8-131842 JP 2005-61156 A Japanese Patent Laid-Open No. 10-278168 WO2003-033144 pamphlet JP 2003-286306 A

  An object of the present invention is a structure in which a photocatalyst layer, an adhesive layer, and a carrier are provided, and the adhesive layer and the photocatalyst layer are sequentially provided on the carrier, and the transparency of the photocatalyst layer and the adhesive layer is maintained for a longer period of time. An object of the present invention is to provide a photocatalyst carrying structure.

  The present inventors have made the photocatalyst layer and the adhesive layer more transparent by using, as the adhesive layer, silica bonded in an elongated shape, in particular, a combination of spherical colloidal silica particles, rod-shaped colloidal silica, or a mixture thereof. It was found that it was retained for a long time, and the present invention was completed.

  That is, the present invention is (1) a structure comprising a photocatalyst layer, an adhesive layer, and a carrier, wherein the adhesive layer and the photocatalyst layer are sequentially provided on the carrier, and the adhesive layer contains silica bonded in an elongated shape. The photocatalyst-supporting structure according to (1) above, wherein (2) 0.1 to 60% by weight of silica bonded in an elongated shape is contained in the adhesive layer The photocatalyst-supporting structure according to (1) or (2) above, wherein (3) the silica bonded in an elongated shape is a connected product of spherical colloidal silica particles, rod-shaped colloidal silica, or a mixture thereof. The photocatalyst-supporting structure according to (3) above, wherein (4) spherical colloidal silica particles have a particle size in the range of 10 to 50 nm, 3 or more colloids The photocatalyst-supporting structure according to the above (3) or (4), wherein the silica is connected, and (6) a connection product of spherical colloidal silica particles having a short side length of 10 to 50 nm. The photocatalyst-supporting structure according to any one of the above (3) to (5), wherein the long side length is in the range of 50 to 400 nm, and (7) rod-shaped colloidal silica, The photocatalyst carrying structure according to any one of (3) to (6) above, wherein the short side has a length in the range of 10 to 50 nm and the long side has a length in the range of 50 to 400 nm. And (8) silica bonded in an elongated shape has a ratio D1 / D2 of the measured particle diameter (D1) measured by the dynamic light scattering method and the measured particle diameter (D2) measured by the nitrogen gas adsorption method is 5 or more, This D1 is 40 to 300 nm and ranges from 5 to 20 nm. A photocatalyst-supporting structure according to any one of the above (1) to (7), wherein the photocatalyst-supporting structure is an amorphous colloidal silica having an extension within only one plane with a thickness within a range, (9) a zirconium compound, The photocatalyst-supporting structure according to any one of the above (1) to (8), further containing at least one selected from the group consisting of an aluminum compound and a silicon compound in a portion other than the carrier, 10) The zirconium compound is one selected from the group consisting of zirconium oxide, oxide hydroxide, hydroxide, oxynitrate, oxycarbonate, alkoxide having 1 to 4 carbon atoms, and hydrolyzate of the alkoxide. Or it is a mixture of 2 or more types, It is related with the photocatalyst carrying structure of said (9) description characterized by the above-mentioned.

In the present invention, (11) the aluminum compound comprises an oxide of aluminum, an oxide hydroxide, a hydroxide, an oxynitrate, an oxycarbonate, an alkoxide having 1 to 4 carbon atoms, and a hydrolyzate of the alkoxide. The photocatalyst-supporting structure according to (9) or (10), wherein the photocatalyst-supporting structure according to the above (9) or (10) is selected from the group, or (12) the silicon compound is a silicon resin, polysiloxane, or colloidal 150 or more photocatalyst-supporting structures according to any one of the above (9) to (11), and (13) a zirconium compound and / or an aluminum compound, which are at least one selected from the group consisting of silica, ℃ a specific surface area after drying above (9) to which is a 100 m 2 / ^g or more porous gel according to any one of (12) The catalyst-supporting structure and (14) photocatalyst layer are converted into oxides, 5 to 60% by weight of zirconium compound, 20 to 90% by weight of aluminum compound, 5 to 60% by weight of titanium oxide, and silicon compound. The photocatalyst layer further contains the photocatalyst-supporting structure according to any one of the above (9) to (13), and (15) silica bonded in an elongated shape. The photocatalyst-supporting structure according to any one of (1) to (14) above, or (16) the haze ratio of the coating film formed by combining the photocatalyst layer and the adhesive layer is 3% or less The haze ratio of the photocatalyst carrying structure according to any one of (1) to (15) and (17) a coating film comprising the photocatalyst layer and the adhesive layer after boiling for 1 hour in boiling ion-exchanged water is 3%. Characterized by the following The photocatalyst carrying structure according to (16) and (18) the photocatalyst carrying structure according to any one of (1) to (17) above, wherein the carrier is for an outer wall.

  Furthermore, the present invention is (19) a coating solution used for forming an adhesive layer in a photocatalyst-supporting structure, which contains silica bonded in an elongated shape, (20) A coating liquid for forming an adhesive layer as described in (19) above, containing 0.01 to 12.0% by weight of silica bonded to an elongated shape in terms of oxide as a solid content, 21) The coating liquid for forming an adhesive layer according to the above (19) or (20), wherein the silica bonded in an elongated shape is a linked product of spherical colloidal silica particles, rod-shaped colloidal silica, or a mixture thereof. (22) The particle size of the spherical colloidal silica particles is in the range of 10 to 50 nm, the coating solution for forming an adhesive layer according to the above (21), and (23) a series of spherical colloidal silica particles. The product is an adhesive layer-forming coating solution as described in (21) or (22) above, wherein 3 or more colloidal silicas are connected, and (24) a connected product of spherical colloidal silica particles, The length of the short side is in the range of 10 to 50 nm, and the length of the long side is in the range of 50 to 400 nm. The adhesive layer formation according to any one of the above (21) to (23), The above-mentioned (21) characterized in that the coating liquid for coating and (25) rod-shaped colloidal silica have a short side length of 10 to 50 nm and a long side length of 50 to 400 nm. The coating liquid for forming an adhesive layer according to any of (24) to (24) and (26) silica bonded in an elongated shape are measured particle diameter (D1) by a dynamic light scattering method and measured particle diameter by a nitrogen gas adsorption method. The ratio D1 / D2 of (D2) is 5 or more D1 is 40 to 300 nm, and is an amorphous colloidal silica having a thickness in the range of 5 to 20 nm and extending only in one plane, wherein the above (19) to (25) Any one of the coating solutions for forming an adhesive layer, (27) a silicon-modified resin containing 2 to 60% by weight of silicon, a resin containing 5 to 40% by weight of colloidal silica, and 3 to 60% by weight of polysiloxane The coating liquid for forming an adhesive layer according to any one of the above (19) to (26), further comprising at least one resin selected from the group consisting of resins, and (28) acrylic-silicon At least one or more of a silicon-modified resin selected from the group consisting of a resin, a silicon-modified resin containing polysiloxane, and a silicon-modified resin containing colloidal silica; The adhesive layer-forming coating solution according to any one of (19) to (26) above, which is contained.

  In the photocatalyst carrying structure including the photocatalyst layer, the adhesive layer, and the carrier of the present invention, the transparency of the photocatalyst layer and the adhesive layer is maintained for a longer period.

  The photocatalyst carrying structure of the present invention is a photocatalyst carrying structure comprising a photocatalyst layer, an adhesive layer, and a carrier, wherein the adhesive layer and the photocatalyst layer are sequentially provided on the carrier, and the adhesive layer is bonded in an elongated shape. It contains silica. The photocatalyst-supporting structure of the present invention includes a photocatalyst layer, an adhesive layer, and a carrier. As long as the adhesive layer and the photocatalyst layer are sequentially provided on the carrier, the other parts further have other configurations. You may do it. Other configurations are not particularly limited. For example, a layer such as a coating layer further present on the photocatalyst layer, an intermediate layer further present between the photocatalyst layer and the adhesive layer, and a printed layer further present between the adhesive layer and the carrier. Etc.

  The adhesive layer in the present invention is not particularly limited as long as it contains silica bonded in an elongated shape. By providing such an adhesive layer between the photocatalyst layer and the carrier, it is possible to prevent the base carrier from deteriorating due to the photocatalytic action of the photocatalyst in the photocatalyst layer, and to adhere the photocatalyst layer to the carrier more firmly. In addition, the transparency of the photocatalyst layer and the adhesive layer can be maintained over a long period of time.

  In the present invention, the silica bonded in an elongated shape includes, for example, those obtained by connecting spherical silica particles into an elongated shape, rod-like silica itself, or a mixture thereof. Among them, spherical colloidal silica particles From the viewpoint of long-term retention of the transparency of the photocatalyst layer and the adhesive layer, the ligated product, rod-shaped colloidal silica, or a mixture thereof is preferable.

  The connected product of spherical colloidal silica particles of the present invention means a product in which spherical colloidal silica particles are connected. Here, “spherical colloidal silica particles” mean colloidal silica particles having a particle diameter in the range of 1 to 1000 nm, preferably 1 to 100 nm, and more preferably 10 to 50 nm. In addition, the spherical colloidal silica particles in the present invention are not limited to a spherical shape in a strict sense, but also include shapes having a different major axis and minor axis, such as a capsule shape and a rugby ball shape. In the present invention, that the colloidal silica particles are connected means that the colloidal silica particles are bonded to each other. The term “coupled” here does not matter whether it is direct or indirect.

Examples of the connected product of spherical colloidal silica particles in the present invention include those in which three or more spherical colloidal silica particles are connected. In addition, the linked product of spherical colloidal silica particles has a short side length of 10 to 50 nm and a long side length of 50 to 400 nm. From the viewpoint of long-term retention of the transparency of the layer, it is preferable.
Here, the short side of the connected product of spherical colloidal silica particles means the particle diameter or short diameter of the smallest spherical colloidal silica particles among the connected spherical colloidal silica particles, and the spherical colloidal silica particles The long side of the connected product means the longest side of the connected product of spherical colloidal silica particles. Among the connected spherical colloidal silica particles in the present invention, a photocatalyst is one in which another spherical colloidal silica particle is connected in a two-dimensional direction (in one plane) starting from a certain spherical colloidal silica particle. From the viewpoint of the long-term retention of transparency of the layer or adhesive layer, it is preferable.

  The spherical colloidal silica particles may have different particle diameters or short diameters in the connection of spherical colloidal silica particles, but from the viewpoint of long-term retention of transparency, the largest particle diameter and the smallest particle diameter Or the difference between the largest minor axis and the smallest minor axis is preferably included in the range of 20 nm, and is preferably included in the range of 10 nm. The shape of the connected product of spherical colloidal silica particles in the present invention is not particularly limited, and may be a linear shape, a branched shape, a bent shape, or the like.

  The rod-shaped colloidal silica in the present invention means colloidal silica whose long side is at least twice as long as the short side. Here, the short side of the rod-shaped colloidal silica means the diameter of the thinnest portion of the rod-shaped colloidal silica, and the long side means the longest side of the rod-shaped colloidal silica. Further, the rod-shaped colloidal silica has a short side length in the range of 10 to 50 nm, and the long side length in the range of 50 to 400 nm is longer in the transparency of the photocatalyst layer and the adhesive layer. It is preferable from the viewpoint of retention.

  The thickness of the rod-shaped colloidal silica in the present invention may not be equal throughout, but the difference between the diameter of the thickest part and the diameter of the thinnest part from the viewpoint of long-term retention of the transparency of the photocatalyst layer or adhesive layer. Is preferably included in the range of 20 nm, and is preferably included in the range of 10 nm. The shape of the rod-shaped colloidal silica in the present invention is not particularly limited, and includes a shape partially containing the rod-shaped colloidal silica. For example, rod-shaped colloidal silica and spherical colloidal silica may be linked, or rod-shaped colloidal silica may be branched or bent.

  In addition, when the connection thing of spherical colloidal silica particle or rod-shaped colloidal silica is a bent shape, the diameter of the longest one side and the narrowest part is measured on the basis of the state extended linearly. Moreover, when the connection thing of spherical colloidal silica particle or rod-shaped colloidal silica is branched, the diameter of the longest one side and the thinnest part is measured on the basis of the state where the longest one side becomes the longest.

  Specifically, the silica bonded in an elongated shape in the present invention has a ratio D1 / D2 of 5 or more as measured particle diameter (D1) measured by dynamic light scattering method and measured particle diameter (D2) measured by nitrogen gas adsorption method. The D1 is 40 to 300 nm, and an elongate amorphous colloidal silica having a thickness in the range of 5 to 20 nm by electron microscope observation and extending only in one plane can be exemplified. As a method for producing such a sol in which colloidal silica is dispersed, the methods described in JP-A-1-317115 and JP-A-7-118008 can be exemplified.

  The content of the silica bonded to the elongated shape contained in the adhesive layer in the present invention is not particularly limited as long as the effect of the present invention that the transparency of the photocatalyst layer and the adhesive layer is maintained over a long period of time can be obtained. On the other hand, it is preferably 0.1 to 60% by weight in terms of oxide, more preferably 1 to 30% by weight, and further preferably 1 to 15% by weight.

  The adhesive layer in the present invention preferably contains a resin in addition to the silica bonded in an elongated shape because a superior adhesive force and a deterioration preventing effect due to photocatalytic action are obtained. More preferably, the resin is almost uniformly composited. The content of the resin in the adhesive layer in the present invention is not particularly limited, but is preferably 30 to 90% by weight, more preferably 60 to 80% by weight as solid content with respect to the total amount of the adhesive layer.

  Such a resin is not particularly limited as long as it can protect the carrier from deterioration due to photocatalysis and can fix the photocatalyst layer. For example, (1) the silicon content is converted into an oxide as a solid. 2 to 60% by weight of silicon-modified resin (acrylic-silicone resin, epoxy silicone resin, polyester silicone resin, etc.), (2) Resin containing 3 to 60% by weight of polysiloxane converted to oxide as a solid (polyethylene (Silicon-modified resin containing siloxane, etc.) or (3) Resin containing 5 to 40% by weight of colloidal silica as an oxide in the form of solid (silicon-modified resin containing colloidal silica) is preferably used. it can. These resins can firmly adhere the photocatalyst and protect the carrier from the photocatalyst.

  When silicon, polysiloxane, or colloidal silica is contained in the above range, the balance between the adhesion to the photocatalyst layer and the adhesion to the carrier is good.

  The resin into which silicon is introduced is not particularly limited, and examples thereof include acrylic resins, epoxy resins, polyester resins, alkyd resins, and urethane resins. Among these, acrylic resins, epoxy resins, and polyester resins are particularly preferable in terms of film formability, toughness, and adhesion to the carrier. These resins can be used in either a solution form or an emulsion type. These resins may contain additives such as a crosslinking agent.

  When the polysiloxane is contained in the resin of the adhesive layer, the polysiloxane is a hydrolyzate of the silicon alkoxide having an alkoxy group having 1 to 5 carbon atoms or the hydrolyzate product, so that more excellent adhesiveness is obtained. And durability is preferred. In addition, polysiloxane obtained by hydrolyzing silicon alkoxide partially containing chlorine can be used.

As such a silicon alkoxide, for example, a silicon alkoxide represented by the following formula (IV) or a hydrolysis product thereof can be preferably used.
Preferable specific examples of the silicon alkoxide represented by the formula (IV) include Si (OCH ₃ ) ₄ , Si (OC ₂ H ₅ ) ₄ , Si (OC ₃ H ₇ ) ₄ , Si (OC ₄ H ₉ ) ₄ , Si (OC ₅ H ₁₁ ) ₄ , Si (OC ₆ H ₁₃ ) ₄ , SiCH ₃ (OCH ₃ ) ₃ , SiCH ₃ (OC ₂ H ₅ ) ₃ , SiCH ₃ (OC ₃ H ₇ ) ₃ , SiCH ₃ ( OC ₃ H ₇ ) ₃ , SiCH ₃ (OC ₄ H ₉ ) ₃ , SiCl (OCH ₃ ) ₃ , SiCl (OC ₂ H ₅ ) ₃ , SiCl (OC ₃ H ₇ ) ₃ , SiCl (OC ₄ H ₉ ) ₃ , SiCl (OC ₆ H ₁₃ ) ₃ , SiCl (OH) (OCH ₃ ) ₂ , SiCl (OH) (OC ₂ H ₅ ) ₂ , SiCl (OH) (OC ₃ H ₇ ) ₂ , SiCl (OH) (OC ₄ H ₉ ) ₂ , SiCl ₂ (OCH ₃ ) ₂ , SiCl ₂ (OC ₂ H ₅ ) _{2 and the} like.

The method for introducing silicon into these silicon-modified resins is not particularly limited. Examples of such methods include transesterification, grafting reaction using silicon macromers and reactive silicon monomers, hydrosilylation reaction, block copolymerization method, and the like.
For example, as a more specific method for introducing polysiloxane into a resin, (1) a method in which silicon alkoxide is mixed with a resin solution in a monomer state and hydrolyzed with moisture in the air when forming an adhesive layer, (2 ) A method in which a partial hydrolyzate of silicon alkoxide is mixed with a resin in advance and further hydrolyzed with moisture in the air when forming the adhesive layer. In order to adjust the hydrolysis rate of silicon alkoxide, a small amount of acid or base catalyst may be added. The amount of polysiloxane added to the resin is preferably 3 to 90% by weight in terms of oxide, based on the total amount of the resin, from the viewpoint of more firmly bonding the photocatalyst layer to the carrier.

  The resin into which polysiloxane is introduced is not particularly limited, and examples thereof include acrylic resins, epoxy resins, polyester resins, urethane resins, alkyd resins, and the like. Among these, it is preferable to use an acrylic resin, an epoxy resin, a polyester resin, or a mixed resin thereof because excellent durability can be obtained when polysiloxane is introduced.

When the resin used for the adhesive layer is a resin containing colloidal silica, the particle diameter of the colloidal silica is not particularly limited, but the particle diameter is 50 nm or less from the viewpoint of durability against photocatalysis and adhesion to the photocatalyst layer. It is preferable.
The method for introducing the colloidal silica into the resin is not particularly limited. One of the simplest methods is a method of forming a protective film by mixing the resin solution and the colloidal silica solution and then applying and drying. A method of polymerizing a resin in a state where is dispersed is also mentioned. Moreover, in order to improve the adhesiveness and dispersibility of colloidal silica and resin, colloidal silica treated with a silane coupling agent can also be used.
The amount of colloidal silica added to the resin is preferably 5 to 90% by weight in terms of oxide with respect to the total amount of the resin from the viewpoint of more firmly bonding the photocatalyst layer to the carrier.

The resin into which the colloidal silica is introduced is not particularly limited, and examples thereof include an acrylic resin, an epoxy resin, a urethane resin, a polyester resin, and an alkyd resin. Of these, acrylic resins, epoxy resins, and polyester resins are preferred because excellent durability can be obtained when colloidal silica is introduced.
Although the manufacturing method in particular of colloidal silica is not restrict | limited, For example, the method of carrying out cation exchange of the sodium silicate aqueous solution, the method of hydrolyzing a silicon alkoxide, etc. are mentioned.

  Furthermore, in the present invention, a resin containing both polysiloxane and colloidal silica can be used as the adhesive layer. In this case, the total amount of polysiloxane and colloidal silica added to the resin is 5 to 90% by weight in terms of oxide, based on the total amount of the resin, because better adhesive strength can be obtained. preferable.

  When the resin used for the adhesive layer is a resin containing colloidal silica and / or a resin containing polysiloxane, the particle size of the colloidal silica or polysiloxane is not particularly limited, but more excellent dispersibility and transparency of the adhesive layer. Since light property is obtained, 50 nm or less is desirable respectively.

  In addition, a light stabilizer and / or an ultraviolet absorber can be further added to the adhesive layer resin for the purpose of suppressing deterioration due to photocatalytic action. The light stabilizer is not particularly limited, but a hindered amine light stabilizer can be preferably used. The ultraviolet absorber is not particularly limited, but a triazole ultraviolet absorber or the like can be used. The addition amount of the light stabilizer and the ultraviolet absorber is not particularly limited, but is preferably 0.005 wt% to 10 wt%, more preferably 0.01 wt% to 5 wt%, respectively, with respect to the adhesive layer resin. can do.

  Moreover, the adhesiveness with a photocatalyst layer can also be improved by processing the surface of the adhesive layer on the side in contact with the photocatalyst layer with, for example, a silane-based or titanium-based coupling agent.

  The method for forming the adhesive layer on the surface of the carrier is not particularly limited. For example, the coating liquid for forming the adhesive layer described below is used as the carrier by a printing method, a sheet molding method, a spray spraying method, a dip coating method, a spin coating method, or the like. A method of coating the surface and drying / curing can be exemplified. The temperature for drying and curing varies depending on the type of solvent and resin, but is generally preferably about 50 ° C to 300 ° C.

  The thickness of the adhesive layer is not particularly limited, but is preferably about 0.1 μm to 20 μm in order to obtain good adhesion with the photocatalyst layer. If the thickness of the adhesive layer is too thin, the adhesive force to the photocatalyst layer may not be sufficient, but if it is too thick, there are few merits.

The photocatalyst in the present invention is not particularly limited as long as it contains a substance having photocatalytic activity (hereinafter referred to as “photocatalyst”). Specifically, as a photocatalyst, TiO ₂ , ZnO, SrTiO ₃ , CdS, GaP, InP, GaAs, BaTiO ₃ , KNbO ₃ , Fe ₂ O ₃ , Ta ₂ O ₅ , WO ₃ , SnO ₂ , Bi ₂ O ₃ , NiO, Cu ₂ O, SiC, SiO ₂ , MoS ₂ , InPb, RuO ₂ , CeO _{2 and the} like can be exemplified, and furthermore, these photocatalysts are Pt, Rh, RuO ₂ , Nb, Cu, Sn, Ni, Fe The thing which added metals or metal oxides, such as, can be used. Of these, those containing titanium oxide (TiO ₂ ) as the main component are particularly preferred in consideration of durability, cost, and photocatalytic activity, and anatase-type titanium oxide is more preferred in consideration of photocatalytic activity. Moreover, not only titanium oxide that shows catalytic activity with light containing a lot of ultraviolet rays such as sunlight, but also titanium oxide that shows catalytic activity even in room light with little ultraviolet rays by doping a noble metal or the like can be used.
Although the photocatalyst layer of this invention may contain only 1 type of photocatalysts, it may contain 2 or more types.

  Further, the photocatalyst layer of the present invention is selected from the group consisting of a zirconium compound, an aluminum compound and a silicon compound in addition to the photocatalyst, from the viewpoint of improvement in adhesion to the adhesive layer and longer-term retention of transparency. It is preferable to contain at least one selected from the above.

  Any photocatalyst can be used as long as it is fixed to the adhesive layer when dried / cured and exhibits photocatalytic activity, such as powder, sol, and solution. In particular, when a sol-like particle having a particle size of 50 nm or less, preferably 20 nm or less is used, the photocatalyst layer is improved in transparency and has a high parallel light transmittance. It is preferable when applied. Further, when a carrier with a color or pattern is used, it is preferable to use such a transparent photocatalyst layer because the base color or pattern is less likely to be damaged. When a photocatalyst having a particle size of 50 nm or more is used, the parallel light transmittance is reduced and the haze ratio is increased as compared with the case of using a photocatalyst having a particle size of 50 nm or less. Here, the haze ratio is a value obtained by a relational expression of haze ratio = (total light transmittance−parallel light transmittance) × 100 / total light transmittance. For example, toilet window glass has high total light transmittance so that the outside sunlight can be sufficiently transmitted and the inside of the toilet becomes bright, and the interior of the toilet should not be clearly visible from the outside. The rate needs to be high.

The total content of the photocatalyst in the photocatalyst layer is preferably 0.1 to 60% by weight and more preferably 10 to 40% by weight in terms of oxide with respect to the photocatalyst layer. Moreover, the same range is mentioned as a preferable range also when a photocatalyst is a titanium oxide. When used in such a range, a well-balanced photocatalyst layer can be obtained from the viewpoint of adhesion to the adhesive layer and photocatalytic activity.
Moreover, when the photocatalyst layer of this invention contains a zirconium compound, content of a zirconium compound becomes like this. Preferably it is 5-60 weight% with respect to a photocatalyst layer, More preferably, it is 10-30 weight%. Moreover, when the photocatalyst layer of this invention contains an aluminum compound, content of an aluminum compound becomes like this. Preferably it is 20 to 90 weight% with respect to a photocatalyst layer, More preferably, it is 20 to 40 weight%. Moreover, when the photocatalyst layer of this invention contains a silicon compound, content of a silicon compound becomes like this. Preferably it is 5-50 weight% with respect to a photocatalyst layer, More preferably, it is 20-40 weight%. Within these ranges, a well-balanced photocatalyst layer can be obtained from the viewpoints of adhesion to the adhesive layer and long-term retention of transparency.
Moreover, when the photocatalyst layer contains any two or more compounds selected from the group consisting of a zirconium compound, an aluminum compound, and a silicon compound, the total of these compounds is preferably 40 to It is 95 weight%, More preferably, it is 60 to 90 weight%. Within these ranges, a well-balanced photocatalyst layer can be obtained from the viewpoints of adhesion to the adhesive layer, longer transparency retention, and photocatalytic activity.

  Zirconium compound is not particularly limited, but zirconium oxide, oxide hydroxide, hydroxide, nitrate, oxynitrate, carbonate, oxycarbonate, oxalate, oxyoxalate, acetate, oxyacetate, Preferred is a gel of one or a mixture of two or more selected from the group consisting of alkoxides having 1 to 6 carbon atoms and hydrolysis products of the alkoxides, zirconium oxide, zirconium oxynitrate, zirconium oxychloride, hydrated zirconium oxide , Zirconium oxyhydroxide, hydrated zirconium nitrate, hydrated zirconium oxychloride, zirconium oxalate, zirconium acetate, zirconium tetraisopropoxide, zirconium tetrabutoxide, zirconium dibutoxide acetylacetonate, zirconium dibutoxide lactate, zirconium Hydrolysis products of Tokishido, hydrolysis products of zirconium isopropoxide is particularly preferred.

  The aluminum compound is not particularly limited, but aluminum oxide, oxide hydroxide, hydroxide, nitrate, oxynitrate, carbonate, oxycarbonate, oxalate, oxysuccinate, acetate, oxyacetate, One or a mixture of two or more selected from the group consisting of alkoxides having 1 to 6 carbon atoms and hydrolysis products of the alkoxides are preferred, and aluminum oxide, aluminum oxide hydroxide, aluminum hydroxide, hydrated aluminum oxide Boehmite, Aluminum nitrate, Aluminum oxynitrate, Aluminum carbonate, Aluminum oxycarbonate, Aluminum oxalate, Aluminum oxyoxalate, Aluminum acetate, Aluminum oxyacetate, Aluminum triisopropoxide, Aluminum tributoxide, Aluminum butoxide acetylacetona DOO, aluminum butoxy Doraku Tate, hydrolysis products of aluminum butoxide, hydrolysis products of aluminum isopropoxide are particularly preferred.

  The particle diameter of the zirconium compound and aluminum compound in the present invention is not particularly limited, but it is preferable to use a sol having a particle diameter of 2 nm to 50 nm, preferably 2 nm to 20 nm. Use of a particle having such a particle size improves the transparency of the photocatalyst layer and increases the parallel light transmittance, which is preferable when it is applied to a glass substrate or plastic molded product that requires transparency. Further, when a carrier with a color or pattern is used, it is preferable to use such a transparent photocatalyst layer because the base color or pattern is less likely to be damaged. When a photocatalyst having a particle size of 50 nm or more is used, the parallel light transmittance is reduced and the haze ratio is increased as compared with the case of using a photocatalyst having a particle size of 50 nm or less.

In the present invention, when a zirconium or aluminum oxide, oxide hydroxide or hydroxide is used, a porous gel having a specific surface area of 100 m ² / g or more after drying at 150 ° C. for 60 minutes is used. It is preferable. The porous gel has adsorptivity and has an effect of enhancing photocatalytic activity.

  In the case of using a sol-like photocatalyst, zirconium compound and / or aluminum compound, an acid or alkali peptizer can be added to the photocatalyst-forming coating solution for stabilization. In addition, a surfactant of 5% by weight or less can be added to the sol suspension with respect to the photocatalyst in order to improve adhesion and operability.

Although it does not restrict | limit especially as a silicon compound in this invention, Silicon resin, polysiloxane, etc. are illustrated, More specifically, for example,
Formula (I)

(In the formula, R ₁ represents an alkyl group which may have a substituent having 1 to 20 carbon atoms, and X ₁ , X ₂ and X ₃ are each independently a chlorine atom, a hydrogen atom, a hydroxyl group or carbon; A silicon compound represented by the following formula (1):
Formula (II)

(In the formula, R ₁ and R ₂ each independently represent an alkyl group which may have a substituent having 1 to 20 carbon atoms, and X ₁ and X ₂ each independently represent a chlorine atom or a hydrogen atom. , A hydroxyl group or an alkoxy group having 1 to 8 carbon atoms.), And a formula (III)

(Wherein R ₁ , R ₂ and R ₃ each independently represents an alkyl group which may have a substituent having 1 to 20 carbon atoms, and X ₁ represents a chlorine atom, a hydrogen atom, a hydroxyl group or carbon. And a silicon compound represented by formula (1) to (8), and one or more silicon compounds selected from the group consisting of hydrolysis products thereof.

Here, as the alkyl group having 1 to 20 carbon atoms, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, neopentyl group Hexyl group, heptyl group, octyl group, decyl group, dodecyl group, octadecyl group and the like. X ₁ , X ₂ and X ₃ represent a chlorine atom, a hydrogen atom, a hydroxyl group or an alkoxy group having 1 to 8 carbon atoms. At this time, X ₁ , X ₂ and X ₃ may be the same or different. Here, as the alkoxy group having 1 to 8 carbon atoms, methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, isobutoxy group, sec-butoxy group, tert-butoxy group, pentyloxy group, hexyloxy group , 2-ethylhexyloxy group, octyloxy group and the like.

  More specifically, among the above silicon compounds, the monosubstituted alkyl silicon compounds represented by the formula (I) include n-butyltrichlorosilane, n-butyltrimethoxysilane, n-decyltrichlorosilane, and n-decyl. Triethoxysilane, dimethoxymethylchlorosilane, n-dodecyltrichlorosilane, n-dodecyltriethoxysilane, ethyltrichlorosilane, ethyltriethoxysilane, ethyltrimethoxysilane, n-heptyltrichlorosilane, n-hexadecyltrichlorosilane, n- Hexadecyltrimethoxysilane, n-hexyltrichlorosilane, n-hexyltriethoxysilane, n-hexyltrimethoxysilane, methyltrichlorosilane, methyltriethoxysilane, n-octadecyltrichlorosilane, n-o Data decyl triethoxysilane, n- octadecyl trimethoxysilane, n- propyl trichlorosilane, n- propyl triethoxysilane, etc. n- propyl trimethoxy silane.

  Examples of the disubstituted alkyl silicon compound represented by the formula (II) include n-butylmethyldichlorosilane, n-decylmethyldichlorosilane, di-n-butyldichlorosilane, diethyldichlorosilane, diethyldiethoxysilane, Di-n-hexyldichlorosilane, dimethyldichlorosilane, dimethyldiethoxysilane, dimethyldimethoxysilane, dimethyldipropoxysilane, dimethylmethoxychlorosilane, di-n-octyldichlorosilane, docosylmethyldichlorosilane, dodecylmethyldichlorosilane, dodecyl Methyldiethoxysilane, ethylmethyldichlorosilane, n-heptylmethyldichlorosilane, n-hexylmethyldichlorosilane, methylpentyldichlorosilane, n-octadecylmethoxydichlorosilane, n Octadecyl methyl dichlorosilane, and propyl methyl dichlorosilane, and the like.

  Examples of the trisubstituted alkyl silicon compound represented by the formula (III) include n-decyldimethylchlorosilane, ethyldimethylchlorosilane, n-octadecyldimethylchlorosilane, n-octadecyldimethylmethoxysilane, n-octyldimethylchlorosilane, n- Examples thereof include propyldimethylchlorosilane, trimethylchlorosilane, trimethylethoxysilane, trimethylmethoxysilane, trimethyl-n-propoxysilane, and tri-n-propylchlorosilane.

In the silicon compound represented by the formula (I), the silicon compound represented by the formula (II), and the silicon compound represented by the formula (III), R ₁ , R ₂ , and R ₃ represent a substituent. It may have and may have a branch. Examples of the substituent include an amino group, a carboxyl group, and a chlorine atom. R ₁ , R ₂ and R ₃ may each independently be an alkyl group which may have a substituent having 1 to 8 carbon atoms.

Among the silicon compounds in the present invention described above,
Formula (IV): SiCln ₁ (OH) n ₂ R ₄ n ₃ (OR ₅ ) n ₄
It is preferable that it is a silicon alkoxide represented by these, or its hydrolysis product. Here, R ₄ is methyl, ethyl, propyl, isopropyl, butyl, s-butyl, t-butyl, hexyl, octyl, aminomethyl, aminoethyl, carboxymethyl, carboxyethyl, chloromethyl, chloroethyl, chloropropyl group, etc. An alkyl group having 1 to 8 carbon atoms (which may be substituted with an amino group, a carboxyl group or a chlorine atom).
R ₅ is an alkyl group having 1 to 8 carbon atoms such as methyl, ethyl, propyl, isopropyl, butyl, s-butyl, t-butyl, hexyl group or the like, or methoxymethyl, ethoxymethyl, propoxymethyl, isopropoxymethyl, butoxy An alkyl group having 1 to 8 carbon atoms substituted with an alkoxy group such as methyl, methoxyethyl, ethoxymethyl, propoxyethyl, methoxypropyl, or methoxybutyl group. N ₁ , n ₂ and n ₃ represent 0, 1 or 2, n ₄ represents an integer of 2 to 4, and n ₁ + n ₂ + n ₃ + n ₄ = 4.

  Preferable specific examples of the silicon alkoxide represented by the formula (IV) include tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane and the like.

  The silicon compound in the present invention may not be a linked product of spherical colloidal silica particles or a rod-shaped colloidal silica, but since the transparency of the photocatalyst layer can be maintained for a longer period of time, a connected product of spherical colloidal silica particles, a rod-shaped colloidal silica Or it is preferable to contain a mixture thereof in the photocatalyst layer. The connected product of spherical colloidal silica particles or rod-shaped colloidal silica and preferred embodiments thereof are the same as the connected product of spherical colloidal silica particles or the colloidal silica material of the above-mentioned adhesive layer.

  The method for forming the photocatalyst layer on the surface of the adhesive layer is not particularly limited. For example, the photocatalyst layer forming coating liquid described below can be prepared by a printing method, a sheet forming method, a spray spraying method, a dip coating method, a spin coating method, or the like. Examples of the method include coating on the surface of the adhesive layer, drying and curing. The temperature during drying and curing varies depending on the carrier material and the resin material in the adhesive layer, but is usually preferably about 50 ° C to 300 ° C.

  The thickness of the photocatalyst layer in the present invention is not particularly limited, but is preferably in the range of 0.1 to 20 μm. When a photocatalyst layer is formed using a specific photocatalyst layer-forming coating solution, the photocatalytic activity obtained tends to increase as the photocatalyst layer becomes thicker, but when the photocatalyst layer thickness exceeds 20 μm. While the photocatalytic activity is almost saturated, the actual coating process is often difficult, and the light transmittance of the photocatalytic layer is lowered. On the other hand, when the thickness of the photocatalyst is less than 0.1 μm, although the light transmissivity is good, most of the ultraviolet rays used when the photocatalyst exerts the photocatalytic action passes through the photocatalyst layer. Activity may not be obtained.

  In the photocatalyst carrying structure of the present invention, the total light transmittance at a wavelength of 550 nm in the coating film including the photocatalyst layer and the adhesive layer may be less than 80%, or the haze ratio may be higher than 2%. It is preferable that the total light transmittance at a wavelength of 550 nm in the coating film combined with the adhesive layer is 80% or more and the haze ratio is 2% or less. Such a photocatalyst-supporting structure uses, for example, a photocatalyst layer having a thickness of the photocatalyst layer in the range of 0.1 to 20 μm and an average particle size of 50 nm or less, and an aluminum oxide or hydroxide gel. As long as the total light transmittance at a wavelength of 550 nm in the coating film including the photocatalyst layer and the adhesive layer is 80% or more and the haze ratio is 2% or less, such a photocatalyst-supporting structure is obtained. It is not limited to the body. When the photocatalyst layer and the adhesive layer are used as a transparent carrier, visible light transmitted through the photocatalyst supporting structure composed of the photocatalyst layer, the adhesive layer and the carrier can be used as illumination, and when used as an opaque carrier. However, since the handle or pattern on the carrier is not damaged, a photocatalyst-supporting structure excellent in decorativeness can be obtained.

  Further, the photocatalyst-supporting structure of the present invention may have a haze ratio of 3% or less, although the coating layer including the adhesive layer and the photocatalyst layer after boiling for 1 hour in boiling ion-exchanged water may be higher than 3%. Preferably there is. Such a photocatalyst-supporting structure uses, for example, a photocatalyst layer having a thickness of the photocatalyst layer in the range of 0.1 to 20 μm and an average particle size of 50 nm or less, and an aluminum oxide or hydroxide gel. However, it is limited to such a photocatalyst-supporting structure as long as the haze ratio of the coating film including the adhesive layer and the photocatalyst layer after boiling in boiling ion exchange water for 1 hour is 3% or less. It is not something.

In addition, the photocatalyst carrying structure of the present invention was obtained by combining the adhesive layer and the photocatalyst layer after irradiating the light of black light having an ultraviolet intensity of 3 mW / cm ² for 500 hours at a temperature of 40 ° C. and a relative humidity of 90%. The haze ratio of the coating film may be higher than 3%, but is preferably 3% or less. Such a photocatalyst-supporting structure uses, for example, a photocatalyst layer having a thickness of the photocatalyst layer in the range of 0.1 to 20 μm and an average particle size of 50 nm or less, and an aluminum oxide or hydroxide gel. The haze of the coating film obtained by combining the adhesive layer and the photocatalyst layer after irradiating the light of a black light with an ultraviolet intensity of 3 mW / cm ² at a temperature of 40 ° C. and a relative humidity of 90% for 500 hours. As long as the rate is 3% or less, it is not limited to such a photocatalyst carrying structure.

  The photocatalyst-supporting structure of the present invention includes architectural paint, wallpaper, window glass, blinds, curtains, carpets, lighting fixtures, lighting lights, road lights, tunnel lighting lights, sound barriers for expressways and bullet trains, black lights, ship bottoms and fishing nets. It can be used for antifouling paints, water treatment fillers, agricultural films, herbicidal sheets, packaging materials, and the like. In particular, when used in a high-temperature and high-humidity environment or in an outdoor environment, it exhibits characteristics such as excellent durability and excellent retention properties.

There are no particular limitations on the material, shape, thickness, etc. of the carrier in the present invention. The material of the carrier may be, for example, ceramics; inorganic materials; organic materials; and the like, and further, an organic polymer in which the carrier material cannot be heated; a metal that is easily oxidized and corroded by heat, water, etc. It may be. Moreover, as a shape of a support | carrier, it can be used even if it is any complicated shape, such as a film form, a sheet form, a plate form, a tubular form, a fiber form, and a net form. The thickness of the carrier is preferably 10 μm or more because the photocatalyst layer and the adhesive layer can be firmly supported. Furthermore, in order to improve the adhesion between the carrier and the adhesive layer, a carrier that has been subjected to easy adhesion treatment such as discharge treatment or primer treatment on the surface can also be used.
The carrier in the present invention is preferably for an outer wall.

  The method for preparing the coating solution for forming an adhesive layer of the present invention is not particularly limited. For example, a method of mixing a spherical colloidal silica particle linked product, rod-shaped colloidal silica, or a mixture thereof with a resin in a solvent. Illustrated.

  The content of silica bonded in an elongated shape contained in the adhesive layer forming coating solution of the present invention is not particularly limited as long as the effect of the present invention that the transparency of the photocatalyst layer and the adhesive layer is maintained over a long period of time can be obtained. The content is preferably 0.01 to 12.0% by weight in terms of oxide with respect to the coating solution for forming the adhesive layer.

  Examples of the solvent used include alcohols such as water, methanol, ethanol, propyl alcohol, isopropyl alcohol, butanol and t-butanol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, acetylacetone and cyclohexanone, diethyl ether, methyl Cellsolve, ethers such as tetrahydrofuran, aromatic hydrocarbons such as benzene, toluene, xylene, halogenated hydrocarbons such as dichloromethane and chloroform, esters such as saxane ethyl, propyl acetate, butyl acetate, pentane, hexane, cyclohexane, etc. Of saturated hydrocarbons.

  The method for preparing the photocatalyst layer forming coating solution is not particularly limited, and examples thereof include a method of mixing a photocatalyst with a zirconium compound, an aluminum compound, and a silicon compound in a solvent. Examples of the solvent include the same solvents as those in the adhesive layer forming coating solution.

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, the technical scope of this invention is not limited to these illustrations.

1) Manufacture of photocatalyst carrying structure The photocatalyst carrying structure of Examples 1-6 which have the structure shown in following Table 1 and Comparative Examples 1-3 was manufactured as follows.

(1) Adhesive layer Silicone-modified resin or the like (PS-1), resin solution (J-1), colloidal silica (KS-1, KS-2) were mixed to obtain an adhesive layer forming solution whose concentration was adjusted. .
This solution was applied and formed on a soda lime glass carrier (TA) by dipping. It was dried at room temperature for 60 minutes to form an adhesive layer having a thickness of 1 μm.
(PS-1): Polyethoxysiloxane (manufactured by Colcoat, trade name: ethyl silicate 40)
(J-1): Acrylic silicone resin xylene solution (silicon content 3% by weight)
The silicon content was expressed in terms of SiO ₂ in the resin solid content.
(KS-1): Colloidal silica (manufactured by Nissan Chemical Co., Ltd., trade name Snowtex PS-S, necklace)
(KS-2): Colloidal silica (manufactured by Catalyst Kasei Kogyo, trade name Cataloid SI-350, granular)

(2) Photocatalyst layer The photocatalyst, silica sol, aluminum compound and zirconium compound shown below are mixed, adjusted to an appropriate range of pH 1.5 to 9, and then added with a predetermined amount of a surfactant to form a photocatalyst complex solution (photocatalyst layer). Forming composition).
The obtained photocatalyst complex solution was applied and formed on the adhesive layer by dipping. The photocatalyst layer was formed at a thickness of 1 μm by drying at the same temperature as that for drying the adhesive layer.
The following were used for the photocatalyst, silica sol, aluminum compound, and zirconium compound.
(T-1): Nitric acid acidic titanium oxide sol (crystal particle diameter: 8 nm)
(KS-1): Colloidal silica (manufactured by Nissan Chemical Co., Ltd., trade name Snowtex PS-S, necklace)
(A-1): Aluminum compound (manufactured by Nissan Chemical Co., Ltd., trade name: Alumina sol-520)
(Z-1): Zirconium compound (zirconium oxynitrate hexahydrate zirconium compound (manufactured by Wako Pure Chemicals, reagent special grade) was dissolved in water to make a 10% aqueous solution, and then heated for 12 hours to remove half of the water. The liquid obtained was used as a zirconium oxynitrate liquid).

2) Performance test of photocatalyst carrying structure The following performance evaluation test was conducted using the photocatalyst carrying structure obtained in 1) above.
(1) Photocatalytic activity evaluation test Using the photocatalyst-supporting structure obtained in 1) above, a test piece having a size of 70 mm x 70 mm was cut out and placed in a 4 L Pyrex (registered trademark) glass container. The mixed gas of air and aldehyde was adjusted to 2000 ppm in this container, and then the sample was irradiated with light of black light (FL15BLB, manufactured by Toshiba Lighting & Technology) with an ultraviolet intensity of ² mW / cm ² for 3 hours, and then inside the container The aldehyde gas concentration was measured by gas chromatography, and the photocatalytic activity was evaluated by the amount of decrease.
As a result, since the photocatalyst carrying structures of Examples 1 to 6 and Comparative Examples 1 to 3 each showed a decrease in aldehyde gas of 100 ppm or more, any photocatalyst carrying structure may exhibit excellent photocatalytic activity. I understood.

(2) Measurement of haze ratio The haze ratio was measured with a turbidimeter (NDH 300A manufactured by Nippon Denshoku Industries Co., Ltd.). Air was measured as a reference. The haze ratio (%) was calculated from the formula “(total light transmittance−parallel light transmittance) × 100 / total light transmittance”. The measurement results are shown in Table 2 below.

(3) Tape peeling test On the surface of each sample, 25 squares were formed at intervals of 2 mm by cuts, and adhesion was evaluated by a cross-cut tape method test defined in JISK5400. Evaluation was made as ○ for those that did not peel, and × for those that did not peel. The evaluation results are shown in Table 2 below.

(4) Finger Friction Test A sample surface was rubbed with a finger, and the sample that was not peeled off was evaluated as ○, and the sample that was peeled off was evaluated as ×. The evaluation results are shown in Table 2 below.

(5) Durability test The sample surface was irradiated with light of ultraviolet light intensity of 3 mW / cm ² with black light in a constant temperature and humidity chamber at a temperature of 40 ° C. and a relative humidity of 90% for 2000 hours, and then a tape peeling test and a finger friction test. The durability was evaluated. The results are shown in Table 2 below.

  From Table 2, the photocatalyst carrying structure of Examples 1-6 maintained the low haze rate also in the accelerated weather resistance test, and had the outstanding weather resistance. In contrast, Comparative Example 1 having an adhesive layer formed from a solution for forming an adhesive layer to which no colloidal silica was added was excellent in adhesion but had a poor weather resistance in haze ratio. The comparative example 2 which has a photocatalyst layer using the photocatalyst composite solution formed only with the photocatalyst and silica sol was a result in which weather resistance is inferior in haze rate and adhesiveness. The comparative example 3 which has the contact bonding layer formed from the solution for contact bonding layer formation which added spherical colloidal silica was a result in which a weather resistance is inferior in haze rate and adhesiveness.

  The photocatalyst-supporting structure of the present invention has high photocatalytic activity and excellent transparency, and the photocatalyst is firmly bonded to the carrier, so that the carrier is not deteriorated by the photocatalytic action and the photocatalyst is not detached. . Further, it can be used for a long time even under light irradiation, and can be used in a hot and humid environment or an outdoor environment.

Claims (2)

  A structure comprising a photocatalyst layer, an adhesive layer, and a carrier, wherein the adhesive layer and the photocatalyst layer are sequentially provided on the carrier, and the photocatalyst layer is converted to an oxide in an amount of 5 to 60% by weight of a zirconium compound, 20 to 90% by weight of aluminum compound, 5 to 60% by weight of titanium oxide, 5 to 50% by weight of silicon compound, the adhesive layer has a short side length of 10 to 50 nm, A silica-modified resin containing 2-60% by weight of silica, and a silica-bonded or colloidal colloidal silica particle having a length in the range of 50 to 400 nm, or a mixture thereof and an elongated shape, and silicon. A photocatalyst-supporting structure comprising at least one resin selected from the group consisting of resins containing 3 to 60% by weight of polysiloxane.   Spherical colloidal silica, which is a coating liquid used for forming an adhesive layer in a photocatalyst-supporting structure, having a short side length of 10 to 50 nm and a long side length of 50 to 400 nm. It is composed of silica bonded to an elongated shape which is a connected particle or rod-shaped colloidal silica, or a mixture thereof, a silicon-modified resin containing 2 to 60% by weight of silicon, and a resin containing 3 to 60% by weight of polysiloxane. A coating solution for forming an adhesive layer, comprising at least one resin selected from the group.