JP2005058931A - Honeycomb catalytic structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a honeycomb catalytic structure which cause no deterioration of base material, allows the surface thereof to exhibit photocatalytic activity for a long period by means of photoirradiation and has excellent deodorizing ability, antifouling ability, antibacterial action and light resistance without requiring elaborate processes. <P>SOLUTION: This honeycomb catalytic structure has a surface layer part containing a photocatalyst (a) and a binder component (B). Therein, the concentration of the photocatalyst (a) in the surface layer part becomes higher from the inside of the honeycomb catalytic structure toward the surface thereof. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention uses a photocatalytic function to decompose organic substances to deodorize or detoxify harmful pollutants, remove NO _x , SO _x , CO _2, etc. in the environment, decolorize dyed wastewater, purify water, etc. The present invention relates to a honeycomb catalyst structure that can be used.

In addition to the conventional environmental pollution problems caused by bad odors and harmful chemical substances generated industrially in factories, etc., and odors caused by waste in service industries such as restaurants and hotels that discharge large amounts of waste, recently With the growing trend toward amenity, the problems of indoor environmental pollution due to bad odors and harmful chemical substances in general living spaces such as indoors and automobiles have been highlighted, and the need for removal of these harmful substances is rapidly increasing. .
For example, in terms of air pollution, high-concentration air pollution due to NOx (nitrogen oxide), SOx (sulfur oxide), etc. in the atmosphere, or air pollution due to dioxins due to waste incineration. For example, in the case of rivers and seas, water pollution is caused by factory wastewater and household wastewater. For example, in terms of the living environment, various environmental pollutions such as formaldehyde, floating bacteria, and foul odors due to building materials have become a problem.

  All countermeasures, research and development are carried out for these environmental pollutions. For example, in terms of air pollution, it is necessary to consider roadside measures, such as roadside measures such as the improvement of green zones and elevated structures, which have already been considered as measures against structures, and have an air purification function. Various research, development, and countermeasures are being conducted, such as the implementation of painting with air purification functions on sound insulation walls and buildings, and various countermeasures have been examined regarding the disposal of garbage by incineration. Set emission control standards, strengthen structural standards and maintenance management standards, prohibit open burning, enact the recycling law for trash, and collect waste separately, or reduce the amount of trash generated Measures such as are taken. For example, in the case of rivers and seas, urgent improvement of sewage, regular water quality surveys to strengthen management standards, and research and development of various water purification equipment. For example, with regard to the living environment, research and development of building materials that do not generate harmful substances, research and development of antibacterial materials, development of deodorizing equipment, and the like are being promoted to improve the environment.

As a method for removing harmful substances such as bad odors and harmful chemical substances, adsorption removal using a porous substance such as activated carbon or zeolite, a so-called adsorbent is common. However, the adsorbent has only an adsorption action for most harmful substances, and if a certain amount of harmful substances are adsorbed, the removal performance is remarkably reduced, or the harmful substances once adsorbed depending on the ambient temperature and the concentration of harmful substances. There was a problem that the substance would leave.
In order to solve such problems, a method of decomposing and removing harmful substances using a catalyst has been devised. Various materials having the ability to decompose and remove harmful substances are known, and among them, a photocatalyst member represented by titanium oxide has attracted much attention in recent years. For example, when titanium oxide is irradiated with ultraviolet rays, alcohol is decomposed in a mixed system of water and alcohol. (See Cundall etal .: J. Oil. Chem. Assoc., 61, 351 (1978)).

  Furthermore, for example, in Japanese Patent Application Laid-Open No. 61-135669, it is reported that when a photocatalyst member such as zinc oxide is irradiated with ultraviolet light, a sulfur compound which is a malodorous substance is decomposed. In the decomposition reaction by these photocatalyst members, the photocatalyst member is not consumed as the reaction proceeds, and its decomposition ability is semi-permanent as long as it is exposed to light. Such a photocatalytic reaction is an interfacial reaction, and proceeds more efficiently as there are more opportunities for contact between the photocatalytic member and the decomposition target. Therefore, the shape of the photocatalyst member is preferably a powder having a large specific surface area, but it is difficult to use the photocatalyst member as a powder, and it is necessary to support and fix it on an appropriate support using some method. There is.

  So far, for example, Japanese Patent Laid-Open No. 8-266601 has proposed a manufacturing method in which a sheet-forming method is formed by a wet papermaking method using a support-forming component composed of titanium oxide, fine fibers and polyester fibers. However, this method has a problem that the support-forming component polyester is decomposed by the photocatalyst. In addition, when activated carbon is combined with a titanium oxide photocatalyst, saturated activated carbon can be refreshed. For example, JP-A-9-948 discloses a method for uniformly and firmly supporting titanium oxide fine particles on an activated carbon substrate. Has been. Further, for example, JP-A-11-138017 discloses a photocatalytic silica gel in which a titanium oxide photocatalyst is supported in pores of a silica gel having an enormous specific surface area and excellent adsorption ability. However, in any of the methods, activated carbon and silica gel have a property of blocking ultraviolet light, and there is a problem that only a very small amount of titanium oxide photocatalyst particles in the vicinity of the surface can participate in decomposition and removal of bad odors. It was. Furthermore, in order to increase the amount of catalyst that receives light irradiation per unit volume, for example, Japanese Patent Application Laid-Open No. 1-189322 and Japanese Utility Model Application Laid-Open No. 2-45130 propose a method of supporting a photocatalyst on a honeycomb structure. However, in these honeycomb-like photocatalyst members, there is little problem of pressure loss and there is a feature that the amount of catalyst that receives light irradiation per unit volume is large, but light irradiation is performed substantially parallel to the catalyst surface, There is a problem that the energy of light irradiated on the catalyst surface is small and it is difficult to obtain sufficient efficiency.

  As a method for solving these problems, for example, Japanese Patent Application Laid-Open No. 2000-342978 discloses a photocatalyst member formed by processing a photocatalyst sheet carrying a photocatalyst into a honeycomb shape, and a cell wall on the opening surface. A photocatalytic member has been proposed in which at least one of the end portions has a photocatalytic layer. According to this method, since the cell wall end portion on the opening surface to which light is most directly irradiated has the photocatalyst layer, it is described that the photocatalytic performance is remarkably excellent, and a high deodorizing effect and antibacterial effect can be obtained. When an organic material is used for the sheet base material, the problem that the base material itself is decomposed by the photocatalytic action has not been solved and there is a problem in terms of durability. In addition, for example, JP 2001-310127 A proposes a multilayer structure in which a honeycomb-like plate coated with titanium oxide to form a photocatalytic active layer is attached as an overlapping layer, Also in this method, as described above, since light irradiation is performed substantially parallel to the catalyst surface, the energy of the light irradiated on the catalyst surface is reduced, and it is difficult to obtain sufficient efficiency. -When organic substance is used for the base material, the problem that the base material itself is decomposed by the photocatalytic action has not been solved.

Further, for example, in Japanese Patent Application Laid-Open No. 2001-79421, a particulate product mainly composed of a titanium oxide photocatalyst and / or a granular product carrying a titanium oxide photocatalyst having a sphere equivalent diameter in the range of 70 μm to 50 mm is used for the honeycomb filter. A honeycomb filter having high-performance photocatalytic ability that has low ventilation resistance and can effectively use ultraviolet light by being provided in a cell and provided with means for preventing the dropping of the granular product on both sides of the honeycomb filter is described. . However, in this method, when the binder to be used is an organic substance, there remains a problem that the binder itself is decomposed by the photocatalytic action as described above. Even when an inorganic binder is used, the honeycomb filter base is used. When an organic material is used as the material, the problem that the base material itself is decomposed by the photocatalytic action has not been solved.
As described above, the honeycomb structure having a photocatalytic function added to it has been focused on solving the problem that the light irradiation necessary for the photocatalytic function is not efficiently performed on the photocatalytic surface due to the structure. Therefore, effective means have been proposed for this problem. However, when the photocatalyst is supported on the honeycomb structure composed of organic matter, the honeycomb structure itself is degraded due to the decomposition action due to the photocatalytic function, or when the organic binder is used, the binder itself is degraded. In fact, the problem that sufficient durability cannot be obtained remains unsolved, and furthermore, there is an actual way to find effective means for efficiently arranging the photocatalyst particles on the light irradiation surface.

Therefore, to solve the problems as described above, to decompose efficiently organic matter by the photocatalytic function, detoxification deodorizing or harmful pollutants, NOx in the environment, SOx, removal of such CO _2, bleaching dyeing wastewater, water A honeycomb catalyst structure excellent in air permeability that can be purified and the like has been desired.
JP-A-8-266601 JP-A-9-948 Japanese Patent Laid-Open No. 11-138017 JP-A 61-135669 JP-A-1-189322 JP-A-2-45130 JP 2000-342978 A JP 2001-310127 A JP 2001-79421 A

The present invention performs an excellent deodorizing effect by photocatalyst or detoxification of harmful pollutants, removal of NOx, SOx, CO2, etc. in the environment, decolorization of dye waste water, purification of water, etc. without requiring complicated processes. An object of the present invention is to provide a honeycomb catalyst structure that can be used.
Specifically, it is to provide a honeycomb catalyst structure having excellent durability without requiring a strict film thickness control of the photocatalyst film or a base material protective layer.

As a result of intensive studies to solve the above problems, the present inventors have reached the present invention. That is, the present invention is as follows.
1. A honeycomb catalyst structure having a surface layer portion containing a photocatalyst (a) and a binder component (B), wherein the concentration of the photocatalyst (a) in the surface layer portion increases from the inner side to the surface of the honeycomb catalyst structure. A honeycomb catalyst structure characterized by comprising:
2. The surface layer portion is in the form of a film, and the concentration of the photocatalyst (a) in the film increases from the surface in contact with the substrate of the honeycomb catalyst structure toward the other exposed surface. Honeycomb catalyst structure.
3. The honeycomb catalyst structure according to invention 1 or 2, wherein the surface layer portion is formed from a photocatalyst composition (C) containing a photocatalyst (a) and a binder component (B).

4). The photocatalyst (a) is a triorganosilane unit represented by the formula (1), a monooxydiorganosilane unit represented by the formula (2), a dioxyorganosilane unit represented by the formula (3), and Modified photocatalyst (A) modified with at least one modifier compound (b) selected from the group consisting of compounds having at least one structural unit selected from the group consisting of methylene fluoride (—CF ₂ —) units The honeycomb catalyst structure according to any one of inventions 1 to 3, wherein:
R ₃ Si- (1)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group)
_{- (R 2 SiO) - (} 2)
(In the formula, R is as defined in formula (1).)

(In the formula, R is as defined in formula (1).)
5). The honeycomb catalyst structure according to any one of inventions 1 to 4, wherein the binder component (B) contains a phenyl group-containing silicone (BP) represented by the following formula (4).
^{_{R 1 p R 2 q X r}} SiO (4-p-q-r) / 2 (4)
(In the formula, each R ¹ represents a phenyl group, and each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or Represents a branched alkenyl group having 2 to 30 carbon atoms, each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or 1 carbon atom; Represents -20 oxime groups and halogen atoms.
And p, q, and r are 0 <p <4, 0 ≦ q <4, 0 ≦ r <4, and 0 <(p + q + r) <4, and 0.05 ≦ p / (p + q) ≦ 1 is there. )

6). The honeycomb catalyst structure according to invention 5, wherein the phenyl group-containing silicone (BP) is a phenyl group-containing silicone (BP1) not containing an alkyl group, represented by the following formula (5).
^{_{R 1 s X t SiO (4}} -s-t) / 2 (5)
(Wherein, R ¹ represents a phenyl group, and each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or an oxime having 1 to 20 carbon atoms. Group represents a halogen atom, s and t are 0 <s <4, 0 ≦ t <4, and 0 <(s + t) <4.

7). The honeycomb catalyst structure according to any one of inventions 5 and 6, wherein the binder component (B) further contains an alkyl group-containing silicone (BA) represented by the following formula (6).
R ² _u X _v SiO _{(4-uv) / 2} (6)
(In the formula, each R ² independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Each independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, or a halogen atom. And u and v are 0 <u <4, 0 ≦ v <4, and 0 <(u + v) <4.)

8). The binder component (B) contains a phenyl group-containing silicone (BP1) represented by the formula (5) and not containing an alkyl group and an alkyl group-containing silicone (BA) represented by the formula (6). A honeycomb catalyst structure according to any one of inventions 1 to 4, which is characterized in that
^{_{R 1 s X t SiO (4}} -s-t) / 2 (5)
(Wherein, R ¹ represents a phenyl group, and each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or an oxime having 1 to 20 carbon atoms. Group represents a halogen atom, s and t are 0 <s <4, 0 ≦ t <4, and 0 <(s + t) <4.
R ² _u X _v SiO _{(4-uv) / 2} (6)
(In the formula, each R ² independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Each independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, or a halogen atom. U and v are 0 <u <4, 0 ≦ v <4, and 0 <(u + v) <4.)

9. The alkyl group-containing silicone (BA) has a monooxydiorganosilane unit (D) represented by the formula (7) and a dioxyorganosilane unit (T) represented by the formula (8). The honeycomb catalyst structure according to claim 7 or 8.
— (R ² ₂ SiO) — (7)
(In the formula, each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Represents an alkenyl group.

(Wherein R ² is as defined in formula (7).)
10. The honeycomb catalyst structure according to any one of inventions 7 to 9, which is a surface layer portion having a phase separation structure for the phenyl group-containing silicone (BP) and the alkyl group-containing silicone (BA).
11. The honeycomb catalyst structure according to invention 10, wherein the photocatalyst (a) is present in the alkyl group-containing silicone (BA) phase.
12 The honeycomb catalyst structure according to invention 3, wherein the photocatalyst (a) has a number average particle diameter of 400 nm or less.

13. The honeycomb catalyst structure according to invention 4, wherein the modifier compound (b) is a Si-H group-containing silicon compound (b1) represented by the formula (9).
H _x R _y SiO _{(4-xy) / 2} (9)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group, where x and y are 0 <x <4, 0 <Y <4 and (x + y) ≦ 4.)

14 The Si-H group-containing silicon compound (b1) is a mono-Si-H group-containing compound represented by the formula (10), a Si-H group-containing compound represented by the formula (11), a formula (12) The honeycomb catalyst structure according to invention 13, wherein the honeycomb catalyst structure is at least one compound selected from the group consisting of H silicones represented by:

(In the formula, each R ³ independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a carbon number of 5 to 20). A cycloalkyl group, a linear or branched fluoroalkyl group having 1 to 30 carbon atoms, a phenyl group, or a siloxy group represented by the formula (13).
—O— (R ⁴ ₂ SiO) _m —SiR ⁴ ₃ (13)
(In the formula, each R ⁴ is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon number of 1 to 1. 30 represents a fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a phenyl group, and m is an integer, and 0 ≦ m ≦ 1000.
H— (R ³ ₂ SiO) _n —SiR ³ ₂ —H (11)
(In the formula, R ³ is as defined in formula (10). N is an integer and 0 ≦ n ≦ 1000.)
(R ³ HSiO) _a (R ³ ₂ SiO) _b (R ³ ₃ SiO _1/2 ) _c (12)
(Wherein R ³ is as defined in formula (10), a is an integer of 1 or more, b is an integer of 0 or more, (a + b) ≦ 10000, and c is 0 or 2) Provided that when (a + b) is an integer of 2 or more and c = 0, the H silicone of formula (12) is a cyclic silicone, and when c = 2, the H silicone of formula (12). Is a chain silicone.)

15. The honeycomb catalyst structure according to invention 1 or 2, wherein the binder component (B) in the surface layer part forms a phase separation structure.
16. The honeycomb catalyst structure according to the invention 1 or 2, which exhibits photocatalytic activity when irradiated with light having energy higher than the band gap energy of the photocatalyst (a) contained in the surface layer portion.
17. By irradiating light having energy higher than the band gap energy of the photocatalyst (a) contained in the surface layer portion, at least a part of the organic group bonded to the silicon atom existing in the vicinity of the photocatalyst (a) particle is a hydroxyl group. The honeycomb catalyst structure according to any one of inventions 4, 5, 7, and 8, wherein the honeycomb catalyst structure is substituted with a siloxane bond.
18. A photocatalyst composition (C) comprising a photocatalyst (a) and a binder component (B), wherein the photocatalyst coating composition for a honeycomb catalyst structure is characterized in that the surface layer portion according to the invention 1 is formed.

  The present invention can exhibit excellent deodorizing properties, stain resistance, antibacterial properties and light resistance over a long period of time without degrading the honeycomb catalyst structure substrate itself by light in the living environment, A honeycomb catalyst structure that is easy to manufacture without requiring a complicated process can be provided.

Hereinafter, the present invention will be described in detail.
The honeycomb catalyst structure of the present invention is a honeycomb catalyst structure having a surface layer portion containing a photocatalyst (a) and a binder component (B), and the concentration of the photocatalyst (a) in the surface layer portion is a honeycomb catalyst structure. The height increases from the inner side to the other exposed surface.
At this time, the photocatalyst content (concentration) in the entire surface layer portion is 100 or more, and the relative concentration in the vicinity of the surface side in contact with the exposed surface expresses the effect of improving the photocatalytic ability and the hydrophilization ability, thereby preventing antifouling. It is preferable because the effect is increased. The relative concentration in the vicinity of the surface side is more preferably 150 or more, and further preferably 200 or more. Further, the relative concentration in the vicinity of the surface in contact with the honeycomb catalyst structure substrate is preferably 50 or less from the viewpoint of the interface deterioration preventing effect. The relative concentration in the vicinity of the surface in contact with the honeycomb catalyst structure substrate is more preferably 10 or less, and even more preferably 0.

Further, the concentration of the photocatalyst (a) in the surface layer portion in the present invention may be gradually increased from the surface in contact with the honeycomb catalyst structure base to the other exposed surface, or simply the honeycomb catalyst structure base. The photocatalyst concentration on the surface in contact with the material may be low, the photocatalyst concentration on the other exposed surface may be high, and the change therebetween may be discontinuous.
Furthermore, in the surface layer portion of the present invention, it is preferable that there is no clear film interface that occurs when a photocatalyst layer is applied on the protective layer. That is, when there is no clear film interface that occurs when a photocatalyst layer is applied on the protective layer, the photocatalyst is firmly fixed in the surface layer portion, and problems such as separation of the photocatalyst do not occur.

In the present invention, the photocatalyst (a) refers to a substance that undergoes an oxidation or reduction reaction upon irradiation with light. That is, when light (excitation light) with an energy larger than the energy gap between the conduction band and the valence band (ie, short wavelength) is irradiated, excitation of electrons in the valence band (photoexcitation) occurs. It is a substance that can generate conduction electrons and holes. At this time, various chemical reactions are performed using the reducing power of electrons generated in the conduction band and / or the oxidizing power of holes generated in the valence band. be able to. For example,
Examples thereof include oxidative decomposition reactions of various organic substances. Therefore, if this photocatalyst is immobilized on the surface of the honeycomb catalyst structure, various organic substances (contaminants) attached to the honeycomb catalyst structure can be oxidized and decomposed using light energy.

  In the present invention, the photocatalytic activity means that an oxidation or reduction reaction is caused by light irradiation. It is possible to determine whether or not the surface is photocatalytically active by measuring the decomposability of the organic material such as a dye during light irradiation on the surface of the material. A surface having photocatalytic activity exhibits excellent decomposition activity and contamination resistance of contaminating organic substances.

In the present invention, examples of the photocatalyst (a) useful for making the surface of the honeycomb catalyst structure photocatalytically active include TiO ₂ , ZnO, SrTiO ₃ , CdS, GaP, InP, GaAs, BaTiO ₃ , and BaTiO _4. BaTi ₄ O ₉ , K ₂ NbO ₃ , Nb ₂ O ₅ , Fe ₂ O ₃ , Ta ₂ O ₅ , K ₃ Ta ₃ Si ₂ O ₃ , WO ₃ , SnO ₂ , Bi ₂ O ₃ , BiVO ₄ , NiO , Cu ₂ O, SiC, MoS ₂ , InPb, RuO ₂ , CeO ₂ , Ta ₃ N _{5 and the} like, and further a layered oxide having at least one element selected from Ti, Nb, Ta, V (for example, JP-A-62-274452, JP-A-2-172535, JP-A-7-24329, JP-A-8-89799, JP-A-8-89 No. 00, JP-A-8-89804, JP-A-8-198061, JP-A-9-248465, JP-A-10-99694, JP-A-10-244165, etc.) I can do it.

Of these photocatalysts (a), TiO ₂ (titanium oxide) is preferable because it is harmless and has excellent chemical stability. As titanium oxide, any of anatase, rutile, and brookite can be used.
When a visible light responsive photocatalyst capable of expressing photocatalytic activity and / or hydrophilicity by irradiation with visible light (for example, a wavelength of about 400 to 800 nm) is selected as the photocatalyst (a) used in the present invention, The honeycomb catalyst structure of the invention is preferable because it can exhibit antifouling performance, an organic substance decomposing action, and the like even in a place where ultraviolet rays are not sufficiently irradiated, such as indoors.

Any visible light responsive photocatalyst can be used as long as it exhibits photocatalytic activity and / or hydrophilicity with visible light. For example, TaON, LaTiO ₂ N, CaNbO ₂ N, LaTaON ₂ , and CaTaO ₂ N can be used. Oxynitride compounds such as JP-A-2002-66333, oxysulfide compounds such as Sm ₂ Ti ₂ S ₂ O ₇ (see JP-A-2002-233770, for example), and nitriding such as Ta ₃ N ₅ Compounds, oxides containing metal ions in the d10 electronic state such as CaIn ₂ O ₄ , SrIn ₂ O ₄ , ZnGa ₂ O ₄ , and Na ₂ Sb ₂ O ₆ (see, for example, JP 2002-59008 A), ammonia and urea In the presence of nitrogen-containing compounds such as titanium oxide precursors (titanium oxysulfate, titanium chloride, alkoxytita Etc.) or nitrogen-doped titanium oxide obtained by firing high surface titanium oxide (for example, JP 2002-29750 A, JP 2002-87818 A, JP 2002-154823 A, JP 2001-207082 A). See), sulfur-doped titanium oxide obtained by firing titanium oxide precursors (titanium oxysulfate, titanium chloride, alkoxytitanium, etc.) in the presence of sulfur compounds such as thiourea, hydrogen plasma treatment or under vacuum Or oxygen-deficient titanium oxide obtained by heat treatment (for example, see JP-A-2001-98219), and further, photocatalyst particles are treated with a halogenated platinum compound (for example, JP-A-2002-239353). And treatment with tungsten alkoxide (see JP 2001-286755 A). The surface-treated photocatalyst obtained by this can be mentioned suitably.

Among the visible light responsive photocatalysts, oxynitride compounds and oxysulfide compounds have a large photocatalytic activity by visible light, and can be used particularly preferably.
Further, the above-described photocatalyst (a) is preferably added or immobilized with a metal such as Pt, Rh, Ru, Nb, Cu, Sn, Ni, Fe and / or an oxide thereof, or with porous calcium phosphate or the like. It can also be used by coating (for example, see JP-A-10-244166).
The crystal particle size (primary particle size) of the photocatalyst (a) is preferably 1 to 400 nm, and more preferably a photocatalyst of 1 to 50 nm is suitably selected.

As the form of the photocatalyst (a) of the present invention, any of powder, dispersion, and sol can be used.
As the photocatalyst (a) of the present invention, it is preferable to use a modified photocatalyst (A) obtained by modifying the photocatalyst (a) with at least one modifier compound (b) described later.
In the present invention, the modification of the photocatalyst (a) means that at least one modifier compound (b) described later is immobilized on the surface of the photocatalyst (a) particles. The immobilization of the above modifier compound on the surface of the photocatalyst particles is considered to be due to van der Waals force (physical adsorption), Coulomb force, or chemical bonding. In particular, modification using a chemical bond is preferable because the interaction between the modifier compound and the photocatalyst is strong, and the modifier compound is firmly immobilized on the surface of the photocatalyst particles.

  By using the photocatalyst (a) of the present invention as the modified photocatalyst (A), when the surface layer portion containing the photocatalyst (a) is formed on the honeycomb catalyst structure base material of the present invention, Formation of a structure in which the concentration of the photocatalyst (a) increases from the surface in contact with the honeycomb catalyst structure substrate of the surface layer portion toward the other exposed surface is easy particularly when combined with the binder component (B) described later Therefore, it is very preferable.

  In the present invention, the properties of the photocatalyst (a) used for modification are important factors for the dispersion stability of the modified photocatalyst (A), film-forming properties, and expression of various functions. That is, as the photocatalyst (a) used for the modification of the present invention, the number average dispersed particle size of a mixture of primary particles and secondary particles (which may be either primary particles or secondary particles) is 400 nm or less. The photocatalyst is preferable because the surface characteristics of the photocatalyst after modification can be effectively used. In particular, when a photocatalyst having a number average dispersed particle size of 100 nm or less is used, in the surface layer portion of the present invention formed from a photocatalyst composition (C) containing a modified photocatalyst (A) to be produced and a binder component (B) described later, Since the modified photocatalyst (A) can be efficiently present on the surface (exposed surface) of the surface layer portion, it is very preferable. More preferably, the photocatalyst (a) having a thickness of 80 nm or less and 3 nm or more, more preferably 50 nm or less and 3 nm or more is suitably selected.

  As these photocatalysts (a), it is preferable to use a photocatalyst sol instead of a photocatalyst powder for the following reasons. In general, powders composed of fine particles form secondary particles in which single crystal particles (primary particles) are strongly agglomerated, so there are many surface properties that are wasted, but it is very difficult to disperse to primary particles. It is. On the other hand, in the case of a photocatalyst sol, the photocatalyst particles do not dissolve but exist in a form close to primary particles, so that the surface characteristics can be used effectively. It can be preferably used because it effectively exhibits various functions. Here, the photocatalyst sol used in the present invention means that the photocatalyst particles are preferably 0.01 to 70% by mass, more preferably 0.1 to 50% by mass in water and / or an organic solvent, and primary particles and / or secondary particles. Dispersed as secondary particles.

  Here, examples of the organic solvent used in the photocatalyst sol include alcohols such as ethylene glycol, butyl cellosolve, n-propanol, isopropanol, n-butanol, ethanol and methanol, and aromatic hydrocarbons such as toluene and xylene. , Aliphatic hydrocarbons such as hexane, cyclohexane and heptane, esters such as ethyl acetate and n-butyl acetate, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, ethers such as tetrahydrofuran and dioxane, dimethylacetamide, dimethyl Examples include amides such as formamide, halogen compounds such as chloroform, methylene chloride, and carbon tetrachloride, dimethyl sulfoxide, nitrobenzene, and a mixture of two or more of these.

  Taking a titanium oxide sol as an example of the photocatalyst sol, for example, a titanium oxide hydrosol in which water is substantially used as a dispersion medium and titanium oxide particles are peptized therein can be exemplified. (Here, substantially using water as a dispersion medium means that water is contained in the dispersion medium in an amount of about 80% by mass or more.) Adjustment of such a sol is known and can be easily produced ( For example, see JP-A-63-17221, JP-A-7-819, JP-A-9-165218, JP-A-11-43327, etc.). For example, metatitanic acid produced by heating and hydrolyzing an aqueous solution of titanium sulfate or titanium tetrachloride is neutralized with aqueous ammonia, and the precipitated hydrous titanium oxide is filtered, washed, and dehydrated to obtain aggregates of titanium oxide particles. It is done. Titanium oxide hydrosol can be obtained by peptizing the agglomerates under the action of nitric acid, hydrochloric acid, ammonia or the like and performing hydrothermal treatment. In addition, as titanium oxide hydrosol, titanium oxide particles are peptized under the action of acid or alkali, or dispersion stabilizer such as sodium polyacrylate is used as required without using acid or alkali. Sols that are used and dispersed in water under strong shear forces can also be used. Further, anatase-type titanium oxide sols having excellent dispersion stability even in an aqueous solution having a pH near neutral and whose particle surface is modified with a peroxo group can be easily obtained by, for example, the method proposed in JP-A-10-67516. Can be obtained.

The titanium oxide hydrosol described above is commercially available as a titania sol. (For example, “STS-02” manufactured by Ishihara Sangyo Co., Ltd., “TO-240” manufactured by Tanaka Transcript Co., Ltd., etc.)
The titanium oxide in the titanium oxide hydrosol is preferably 50% by mass or less, more preferably 30% by mass or less. More preferably, it is 30 mass% or less and 0.1 mass% or more.
Such hydrosols have a relatively low viscosity (20 ° C.). In the present invention, the viscosity of the hydrosol is preferably in the range of about 0.05 mPa · s to 2000 mPa · s. More preferably, it is 0.5 mPa * s-1000 mPa * s, More preferably, it is 1 mPa * s-500 mPa * s.

Further, for example, a cerium oxide sol (for example, see JP-A-8-59235) or a layered oxide sol having at least one element selected from the group consisting of Ti, Nb, Ta, and V (for example, No. 25123, JP-A-9-67124, JP-A-9-227122, JP-A-9-227123, JP-A-10-259023, etc.), etc. It is known as well as titanium oxide sol.
Furthermore, a visible light responsive photocatalyst sol that can be suitably used in the present invention is also commercially available. (For example, “NTB-200” manufactured by Showa Denko KK, “TSS” manufactured by Sumitomo Chemical Co., Ltd., etc.)

  In addition, a photocatalyst organosol in which an organic solvent is substantially used as a dispersion medium and in which photocatalyst particles are dispersed is a compound having a phase transfer activity such as polyethylene glycol (for example, different first phase and second phase). A third phase is formed at the interface with the phase, the first phase, the second phase, the third phase are mutually dissolved and / or solubilized compounds) and diluted with an organic solvent (for example, JP-A-10-167727), a method for preparing a sol by dispersing and transferring it in an organic solvent insoluble in water with an anionic surfactant such as sodium dodecylbenzenesulfonate (for example, JP-A-58-29863). Gazette) and alcohols having a boiling point higher than that of water such as butyl cellosolve are added to the photocatalyst hydrosol, and then the water can be obtained by (reduced pressure) distillation or the like.In addition, a titanium oxide organosol in which an organic solvent is substantially used as a dispersion medium and titanium oxide particles are dispersed therein is commercially available (for example, “TKS-251” manufactured by Teika Co., Ltd.). Here, substantially using an organic solvent as a dispersion medium means that the organic solvent is contained in the dispersion medium in an amount of about 50% by mass or more.

In the present invention, at least one modifier compound (b) used to obtain the modified photocatalyst (A) is a triorganosilane unit represented by the formula (1), a monooxy represented by the formula (2). From the group consisting of compounds having at least one structural unit selected from the group consisting of diorganosilane units, dioxyorganosilane units represented by formula (3), and methylene fluoride (—CF ₂ —) units. To be elected.
R ₃ Si- (1)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group)
_{- (R 2 SiO) - (} 2)
(In the formula, R is as defined in formula (1).)

(In the formula, R is as defined in formula (1).)
In the modified photocatalyst (A) in which the surface of the photocatalyst particle is modified with the modifier compound (b) having the structural unit described above, the surface energy of the particle surface is very small.
In the present invention, the modification treatment of the photocatalyst (a) with the modifier compound (b) is carried out in the presence or absence of water and / or an organic solvent in the same manner as the above-described photocatalyst (a). b) is preferably mixed at a mass ratio (a) / (b) = 1/99 to 99.9 / 0.1, more preferably (a) / (b) = 10/90 to 99/1. Preferably, it can be obtained by heating at 0 to 200 ° C., more preferably at 10 to 80 ° C., or by changing the solvent composition of the mixture by (reduced pressure) distillation or the like.

  Here, when performing the above modification treatment, examples of organic solvents that can be used include aromatic hydrocarbons such as toluene and xylene, aliphatic hydrocarbons such as hexane, cyclohexane, and heptane, ethyl acetate, and n-butyl acetate. Esters, alcohols such as ethylene glycol, butyl cellosolve, isopropanol, n-butanol, ethanol and methanol, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, ethers such as tetrahydrofuran and dioxane, amides such as dimethylacetamide and dimethylformamide , Halogen compounds such as chloroform, methylene chloride, carbon tetrachloride, dimethyl sulfoxide, nitrobenzene, and a mixture of two or more thereof.

Examples of the modifier compound (b) used to obtain the modified photocatalyst (A) of the present invention include Si-H groups, hydrolyzable silyl groups (alkoxysilyl groups, hydroxysilyl groups, halogenated silyl groups, Acetoxysilyl group, aminoxysilyl group, etc.), epoxy compounds, acetoacetyl groups, thiol groups, acid anhydride groups and other photocatalyst particles (a) reactive with silicon compounds, fluoroalkyl compounds, fluoroolefin polymers, etc. Can be mentioned.
Other examples of the modifier compound (b) include interaction with photocatalyst particles (a) such as polyoxyalkylene groups, sulfonic acid groups, and carboxyl groups by van der Waals force, Coulomb force, and the like. Examples thereof include a silicon compound having a structure, a fluoroalkyl compound, and a fluoroolefin polymer.

In the present invention, when the Si-H group-containing silicon compound (b1) represented by the composition formula (9) is used as the modifier compound (b), the surface of the photocatalyst particles can be modified very efficiently. preferable.
H _x R _y SiO _{(4-xy) / 2} (9)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group, where x and y are 0 <x <4, 0 <Y <4 and (x + y) ≦ 4.)

In the present invention, the modification of the photocatalyst (a) with the Si—H group-containing silicon compound (b1) represented by the above composition formula (9) is carried out in the presence or absence of water and / or an organic solvent. The mass ratio (a) / (b1) = 1/99 to 99.9 / 0.1, more preferably (a) / (b1), between (a) and the Si—H group-containing silicon compound (b1). = 10/90 to 99/1, preferably by mixing at 0 to 200 ° C. By this modification operation, hydrogen gas is generated from the mixed solution, and when the photocatalyst sol is used as the photocatalyst (a), an increase in the average dispersed particle diameter is observed. For example, when titanium oxide is used as the photocatalyst (a), a decrease in Ti—OH groups is observed as a decrease in absorption at 3630 to 3640 cm ^{−1 in} the IR spectrum by the above modification.

  From these, when the Si-H group-containing silicon compound (b1) represented by the above formula (9) is selected as the modifier compound (b), the modified photocatalyst (A) of the present invention is Si-H. This is very preferable because it is not a mere mixture of the group-containing silicon compound (b1) and the photocatalyst (a), but it can be predicted that some kind of interaction accompanying a chemical reaction occurs between the two. In fact, the modified photocatalyst (A) thus obtained is very excellent in dispersion stability, chemical stability, durability and the like in an organic solvent.

In the present invention, the modification of the photocatalyst (a) with the Si—H group-containing silicon compound (b1) represented by the above formula (9) is preferably performed using a dehydrogenative condensation catalyst for Si—H groups. It can also be carried out at 150 ° C.
In this case, the dehydrogenation condensation catalyst may be fixed to the photocatalyst (a) in advance by a method such as a photoreduction method and may be modified with the Si-H group-containing silicon compound (b1), or the presence of the dehydrogenation condensation catalyst. Under the above, the photocatalyst (a) may be modified with the Si—H group-containing compound silicon (b1).

Here, the dehydrogenative condensation catalyst for the Si-H group is an active hydrogen group such as a Si-H group and a hydroxyl group (Ti-OH group in the case of titanium oxide) existing on the photocatalyst surface, a thiol group, an amino group, or a carboxyl group. Furthermore, it means a substance that accelerates the dehydrogenation condensation reaction with water or the like, and the use of the dehydrogenation condensation catalyst makes it possible to modify the surface of the photocatalyst under mild conditions.
Examples of the dehydrogenative condensation catalyst include platinum group catalysts, that is, ruthenium, rhodium, palladium, osmium, iridium, platinum simple substance and compounds thereof, and simple substances such as silver, iron, copper, cobalt, nickel, tin and compounds thereof. Can be mentioned. Of these, platinum group catalysts are preferred, and platinum alone and its compounds are particularly preferred.

Here, as the platinum compound, for example, platinum chloride (II), tetrachloroplatinic acid (II), platinum chloride (IV), hexachloroplatinic acid (IV), hexachloroplatinum (IV) ammonium, hexachloroplatinum (IV) Potassium, platinum hydroxide (II), platinum dioxide (IV), dichloro-dicyclopentadienyl-platinum (II), platinum-vinylsiloxane complex, platinum-phosphine complex, platinum-olefin complex, etc. can be used. .
In the Si—H group-containing silicon compound represented by the above formula (9) of the present invention, the Si—H group is a preferred functional group for modifying the photocatalyst with good selectivity under mild conditions. On the other hand, the hydrolyzable group can also be used for the modification of the photocatalyst, but in order to suppress side reactions and improve the stability of the resulting modified photocatalyst, the content thereof should be smaller. preferable.

  Examples of the Si-H group-containing silicon compound (b1) represented by the above formula (9) that can be suitably used in the present invention include a mono-Si-H group-containing compound represented by the formula (10), a formula (11) Si-H group-containing compound having no hydrolyzable silyl group, at least one selected from the group consisting of Si-H group-containing compound represented by formula (12) and H silicone represented by formula (12) Can be mentioned.

(In the formula, each R ³ independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a carbon number of 5 to 20). A cycloalkyl group, a linear or branched fluoroalkyl group having 1 to 30 carbon atoms, a phenyl group, or a siloxy group represented by the formula (13).
—O— (R ⁴ ₂ SiO) _m —SiR ⁴ ₃ (13)
(In the formula, each R ⁴ is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon number of 1 to 1. 30 represents a fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a phenyl group, and m is an integer and 0 ≦ m ≦ 1000.)

H— (R ³ ₂ SiO) _n —SiR ³ ₂ —H (11)
(In the formula, R ³ is as defined in formula (10). N is an integer and 0 ≦ n ≦ 1000.)
(R ³ HSiO) _a (R ³ ₂ SiO) _b (R ³ ₃ SiO _1/2 ) _c (12)
(Wherein R ³ is as defined in formula (10), a is an integer of 1 or more, b is an integer of 0 or more, (a + b) ≦ 10000, and c is 0 or 2) Provided that when (a + b) is an integer of 2 or more and c = 0, the H silicone of formula (12) is a cyclic silicone, and when c = 2, the H silicone of formula (12). Is a chain silicone.)
In the present invention, specific examples of the mono-Si—H group-containing compound represented by the formula (10) include, for example, bis (trimethylsiloxy) methylsilane, bis (trimethylsiloxy) ethylsilane, bis (trimethylsiloxy) n-propylsilane. Bis (trimethylsiloxy) i-propylsilane, bis (trimethylsiloxy) n-butylsilane, bis (trimethylsiloxy) n-hexylsilane, bis (trimethylsiloxy) cyclohexylsilane, bis (trimethylsiloxy) phenylsilane, bis (triethylsiloxy) ) Methylsilane, bis (triethylsiloxy) ethylsilane, tris (trimethylsiloxy) silane, tris (triethylsiloxy) silane, pentamethyldisiloxane, 1,1,1,3,3,5,5-heptamethyltrisilo Sun, 1,1,1,3,3,5,5,6,6-nonamethyltetrasiloxane, trimethylsilane, ethyldimethylsilane, methyldiethylsilane, triethylsilane, phenyldimethylsilane, diphenylmethylsilane, cyclohexyldimethylsilane , T-butyldimethylsilane, di-t-butylmethylsilane, n-octadecyldimethylsilane, tri-n-propylsilane, tri-i-propylsilane, tri-i-butylsilane, tri-n-hexylsilane, triphenyl Examples thereof include silane, allyldimethylsilane, 1-allyl-1,1,3,3-tetramethyldisiloxane, chloromethyldimethylsilane, and 7-octenyldimethylsilane.

  Among these mono-Si-H group-containing compounds, bis (trimethylsiloxy) methylsilane and tris are preferred because of the good reactivity (dehydrogenation condensation reaction) and low surface energy of Si-H groups during photocatalytic modification treatment. Those represented by the following formula (14) having a siloxy group in the molecule, such as (trimethylsiloxy) silane, pentamethyldisiloxane and the like and having no phenyl group are preferable.

(In the formula, each R ⁵ is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a linear or branched alkenyl group having 1 to 30 carbon atoms, or a carbon number of 5 to 5. 20 cycloalkyl groups, a linear or branched fluoroalkyl group having 1 to 30 carbon atoms, or a group consisting of one or more selected from a siloxy group represented by formula (13b), and At least one of R ⁵ is a siloxy group represented by the formula (13b).
—O— (R ⁴ ′ ₂ SiO) _m —SiR ⁴ ′ ₃ (13b)
(In the formula, each R ⁴ ′ is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon number. Represents 1 to 30 fluoroalkyl groups, m is an integer, and 0 ≦ m ≦ 1000.))

  In the present invention, specific examples of the both-terminal Si—H group-containing compound represented by the above formula (11) include 1,1,3,3-tetramethyldisiloxane, 1,1,3,3,5, and the like. , 5-hexamethyltrisiloxane, 1,1,3,3,5,5,7,7-octamethyltetrasiloxane and the like H-terminal polydimethylsiloxanes having a number average molecular weight of 50000 or less, Number average molecular weight of 50,000 or less such as 3-tetraethyldisiloxane, 1,1,3,3,5,5-hexaethyltrisiloxane, 1,1,3,3,5,5,7,7-octaethyltetrasiloxane H-terminal polydiethylsiloxanes, 1,1,3,3-tetraphenyldisiloxane, 1,1,3,3,5,5-hexaphenyltrisiloxane, 1,1,3,3,5,5 , 7,7-octa H-terminal polydiphenylsiloxanes having a number average molecular weight of 50,000 or less, 1,3-diphenyl-1,3-dimethyl-disiloxane, 1,3,5-trimethyl-1,3,5-triphenyl -H-terminal polyphenylmethylsiloxanes having a number average molecular weight of 50000 or less, such as trisiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetraphenyl-tetrasiloxane, dimethylsilane, ethylmethyl Examples thereof include silane, diethylsilane, phenylmethylsilane, diphenylsilane, cyclohexylmethylsilane, t-butylmethylsilane, di-t-butylsilane, n-octadecylmethylsilane, and allylmethylsilane.

Among these, the number average molecular weight is preferably 10000 or less, more preferably 2000 or less, more preferably due to the good reactivity of the Si—H group (dehydrogenation condensation reaction) and the low surface energy during the modification of the photocatalyst. Preferably 1000 or less H-terminated polydialkylsiloxanes (formula (15)) can be suitably used as the Si-H group-containing compound at both ends.
H— (R ⁶ ₂ SiO) _d —SiR ⁶ ₂ —H (15)
(In the formula, each R ⁶ independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, or a linear or branched fluoroalkyl group having 1 to 30 carbon atoms. D Is an integer, 0 ≦ d ≦ 1000.)
The H silicone represented by the above formula (12) used in the present invention has a number average molecular weight of preferably 5,000 or less, more preferably from the viewpoint of dispersion stability (preventing aggregation of photocatalyst particles) during photocatalytic modification treatment. H silicone of 2000 or less, more preferably 1000 or less can be suitably used.

  Moreover, when the fluororesin (b2) having the structure represented by the general formula (20) is used as the modifier compound (b) used in the present invention, a modified photocatalyst (A) modified with the fluororesin (A) ) Is preferable because it is excellent in both decomposability of harmful substances and organic base material protection.

(Wherein A ^{1 to} A ⁵ may be the same or different and are each selected from a fluorine atom, a hydrogen atom, a chlorine atom, an alkyl group having 1 to 6 carbon atoms, and a halo-substituted alkyl group having 1 to 6 carbon atoms) Y represents a w-valent organic group having a molecular weight of 14 to 50000 (a group having a w-value other than the bond to the main chain of the organic group Y, preferably a group having a methylene fluoride unit, more preferably V represents an epoxy group, a hydroxyl group, an acetoacetyl group, a thiol group, a cyclic acid anhydride group, a carboxyl group, a sulfonic acid group, a polyoxyalkylene group, or a hydrolyzable silyl group. Represents at least one functional group selected from the group consisting of: k is an integer of 0 or more and 1000000 or less, and l is an integer of 1 or more and 100000 or less, provided that k = 0 is preferable. The at least one fluorine atom in ^A 3 to A ^5, more preferably an integer of .w 1 to 20 representing the ^A 3, ^{A 4} are both fluorine atoms.)

In the present invention, the modification of the photocatalyst (a) with the fluorine-based resin (b2) represented by the formula (20) is performed in the presence or absence of water and / or an organic solvent. The resin (b2) is preferably a mass ratio (a) / (b2) = 1/99 to 99.9 / 0.1, more preferably a ratio of (a) / (b2) = 10/90 to 99/1 It is preferably obtained by mixing at 0 to 200 ° C. and preferably by changing the solvent composition of the mixture by distillation under reduced pressure.
Preferable examples of the fluororesin (b2) include a perfluorocarbon sulfonic acid polymer fluororesin (b2 ′) having a structure represented by the formula (21), for example.

(In the formula, x is an integer of 1 to 1000000, y represents an integer of 1 to 100000, m represents an integer of 0 to 20, and n represents an integer of 0 to 20).
In the modified photocatalyst (A) of the present invention, its preferred form is that the number average dispersed particle size of the mixture of primary particles and secondary particles of the modified photocatalyst (which may be either primary particles or secondary particles) is 400 nm or less. More preferably, it is 1 nm or more and 100 nm or less, and particularly preferably 5 nm or more and 80 nm or less. A sol state is preferable.

In particular, when a modified photocatalyst sol having a number average dispersed particle size of 100 nm or less is used for the photocatalyst composition (C) of the present invention, the concentration of the modified photocatalyst particles is small in the vicinity of the interface contacting the honeycomb catalyst structure substrate, and the surface layer portion It is advantageous to form a surface layer part that is anisotropically distributed in the surface direction that is largely distributed in the vicinity of the surface of the material, and there is no interface deterioration with the honeycomb catalyst structure substrate due to the photocatalytic action, and a surface layer part with high photocatalytic activity is formed This is very preferable. Such a modified photocatalyst sol can be obtained by using the above-mentioned photocatalyst sol as a photocatalyst to be modified with the above modifier compound (b).
Conventionally, a numerical value simply displayed as a particle diameter in titanium dioxide or the like is a primary particle diameter (crystallite diameter) in many cases, and is not a numerical value considering a secondary particle diameter due to aggregation.

The photocatalyst composition (C) forming the surface layer part of the present invention comprises a photocatalyst (a) (preferably a modified photocatalyst (A)) and a binder component (B), and its mass ratio (A) / ( B) is preferably 0.1 / 99.9 to 90/10, and more preferably (A) / (B) is included at 1/99 to 50/50.
The modified photocatalyst (A) of the present invention is modified with a modifier compound (b) having a structure having a very small surface energy {formula (1) to (3), at least one selected from methylene fluoride units}. Therefore, when the surface layer portion is formed, it has a property of being easily moved to the surface layer surface on the side in contact with air.

  Here, as the binder component (B) of the present invention, by using a photocatalyst (a), in particular, a binder component having a surface energy higher than that of the modified photocatalyst (A), the above properties of the modified photocatalyst (A) are promoted. The photocatalyst composition (C) of the present invention can have a large self-gradient with respect to the distribution of the photocatalyst (a), particularly the modified photocatalyst (A). Here, the self-grading property means that when the surface layer portion is formed from the photocatalyst composition (C), the photocatalyst (a), particularly the modified photocatalyst (A), in the formation process, the property of the surface layer portion or the interface with which it contacts (particularly hydrophilic / Corresponding to (hydrophobic), this means that a structure having a concentration gradient of the photocatalyst (a), particularly the modified photocatalyst (A) is autonomously formed.

As the binder component (B) of the present invention, when a resin having a surface energy of 2 mN / m or more, preferably 5 mN / m or more larger than that of the photocatalyst (a) (preferably the modified photocatalyst (A)) is selected, the self-gradient Is very preferable.
Here, the surface energy and the relative difference between the surface energies can be determined by referring to, for example, Polymer Handbook (published by A Wiley-interscience publication in the United States) or by the following method.
That is, the base material which has each surface layer part from the photocatalyst (a) which comprises the said photocatalyst composition (C), especially a modified | denatured photocatalyst (A), and a binder component (B) is adjusted, and deionized water is dripped. The contact angle (θ) at 20 ° C. is measured, and the surface energy of each can be determined by the following empirical formulas for Sell and Neumann.

[Wherein γs represents the surface energy (mN / m) of the surface layer portion where the contact angle of deionized water was measured, and γl represents the surface energy of water {72.8 mN / m (20 ° C.)}. ]
In the photocatalyst composition (C) of the present invention, the compound that can be used for the binder component (B) is not particularly limited as long as it has a surface energy that satisfies the above conditions, but various monomers, synthetic resins, natural resins, etc. In addition, after the formation of the coating film or the molded body, those that are cured by drying, heating, moisture absorption, light irradiation or the like can also be mentioned. Further, the form thereof may be in a solvent-free state (pellet, powder, liquid, etc.) or may be dissolved or dispersed in a solvent, and is not particularly limited.

As the synthetic resin, a thermoplastic resin and a curable resin (thermosetting resin, photocurable resin, moisture curable resin, etc.) can be used. For example, silicone resin, acrylic resin, methacrylic resin, fluororesin, Alkyd resin, amino alkyd resin, vinyl resin, polyester resin, styrene-butadiene resin, polyolefin resin, polystyrene resin, polyketone resin, polyamide resin, polycarbonate resin, polyacetal resin, polyether ether ketone resin, polyphenylene oxide resin, polysulfone resin, Polyphenylene sulfone resin, polyether resin, polyvinyl chloride resin, polyvinylidene chloride resin, urea resin, phenol resin, melamine resin, epoxy resin, urethane resin, silicone-acrylic resin, water glass and zirco Um compounds, mention may be made of inorganic compounds such as titanium peroxide.
Examples of the natural polymer include cellulose resins such as nitrocellulose, isoprene resins such as natural rubber, protein resins such as casein, and starch.

In the present invention, as the binder component (B) used in the photocatalyst composition (C), the phenyl group-containing silicone (BP) represented by the following formula (4) is more surface energy than the modified photocatalyst (A1) of the present invention. Since the siloxane bond (—O—Si—) constituting the skeleton does not undergo oxidative decomposition due to photocatalysis, it can be most preferably used.
^{_{R 1 p R 2 q X r}} SiO (4-p-q-r) / 2 (4)
(In the formula, each R ¹ represents a phenyl group, and each R ² independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or Represents a branched alkenyl group having 2 to 30 carbon atoms, each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or 1 carbon atom; Represents an oxime group of ˜20, a halogen atom, and p, q and r are 0 <p <4, 0 ≦ q <4, 0 ≦ r <4, and 0 <(p + q + r) <4, and 0 .05 ≦ p / (p + q) ≦ 1.)
Examples of the phenyl group-containing silicone (BP) represented by the above formula (4) include at least one structure of a siloxane bond represented by the general formulas (16), (17), (18), and (19). Mention may be made of silicone.

— (R ⁷ ₂ SiO) — (17)

(In the formula, each R ⁷ independently represents a phenyl group, a linear or branched alkyl group having 1 to 30 carbon atoms, or a cycloalkyl group having 5 to 20 carbon atoms.)

The silicone containing the above-described structure is, for example, a general formula R ⁷ SiX ₃ (wherein R ⁷ is a phenyl group, a linear or branched alkyl group having 1 to 30 carbon atoms, or a cycloalkyl group having 5 to 20 carbon atoms). Each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, or a halogen atom. Represents a reactive group selected from the group. The same shall apply hereinafter.) And / or a bifunctional silane derivative represented by the general formula R ⁷ ₂ SiX ₂ and / or a general formula SiX ₄ tetrafunctional silane derivative represented partially by hydrolysis and polycondensation, prepared by end-stopped by monofunctional silane derivative and / or alcohols of the general formula R ^{7 3} _SiX necessary Kill. The polystyrene-converted weight average molecular weight of the partial condensate of the silane derivative monomer thus obtained is preferably 100 to 100,000, more preferably 400 to 50,000.

Among these, when a phenyl group-containing silicone represented by the above formula (4) is selected to contain a ladder structure represented by the above formula (16) of 10 mol% or more, preferably 40 mol% or more, the present invention The photocatalyst-containing surface layer portion formed from the photocatalyst composition (C) is preferable because it is very excellent in terms of hardness, heat resistance, weather resistance, stain resistance, chemical resistance, and the like. In particular, those having a phenyl ladder structure as the ladder structure [wherein all R ⁷ in the formula (16) are phenyl groups] are preferable because the physical properties of the above-described photocatalyst-containing surface layer portion are greatly improved. Such ladder structure, for example can be identified by the presence of absorption derived from two siloxane bonds near 1040 cm ^-1 and 1160 cm ^-1 in the infrared absorption spectrum.
(See JFBrown. Jr., etal .: J. Am. Chem. Soc., 82, 6194 (1960).)
The phenyl group-containing silicone (BP) represented by the above formula (4) used in the present invention preferably has a Ph—Si bond (Ph: phenyl group).

That is, in the photocatalyst composition (C) of the present invention, the modifier compound (b) having a structure having a very small surface energy {formula (1) to (3), at least one selected from methylene fluoride units}. By using the binder component (B) containing a phenyl group-containing silicone (BP) having a surface energy higher than that of the modified photocatalyst (A) as the binder of the modified photocatalyst (A) that has been modified, the photocatalyst composition of the present invention (C) is preferable because it can have a very high self-gradient with respect to the distribution of the modified photocatalyst (A).
Such a self-gradient effect by the phenyl group-containing silicone (BP) having a high surface energy is obtained by converting the phenyl group (R ¹ ) into the phenyl group (R ¹ ) and R ² (R ² is linear or branched). Represents an alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, and an alkenyl group having 2 to 20 carbon atoms) (hereinafter referred to as (R ¹ + R ² )). }, A phenyl group-containing silicone (BP) represented by the above formula (4) having 5 mol% or more of Is preferred.

In addition, the self-tilting effect described above increases as the ratio of the phenyl group (R ¹ ) to (R ¹ + R ² ) increases. Therefore, the more preferable phenyl group-containing silicone of the binder component (B) used in the photocatalyst composition of the present invention is more preferably a ratio of phenyl group (R ¹ ) to (R ¹ + R ² ) of 10 mol% or more. Is 20 mol% or more, more preferably 50 mol% or more.
In addition, the phenyl group-containing silicone (BP) has good adhesion to an organic substrate such as an organic resin, and the siloxane bond (—O—Si—) constituting the skeleton does not undergo oxidative decomposition due to photocatalysis, The photocatalyst-containing surface layer part obtained by coating the honeycomb catalyst structure base material with the photocatalyst composition (C) of the present invention has extremely excellent weather resistance.

In the photocatalyst composition (C) of the present invention, the phenyl group-containing silicone (BP) used in the binder component (B) is more preferably an alkyl group represented by the following formula (5), which exhibits the above-described effects. It is a phenyl group-containing silicone (BP1) that does not contain.
^{_{R 1 s X t SiO (4}} -s-t) / 2 (5)
(Wherein, R ¹ represents a phenyl group, and each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or an oxime having 1 to 20 carbon atoms. Group represents a halogen atom, and s and t are 0 <s <4, 0 ≦ t <4, and 0 <(s + t) <4.)

In addition, when the binder component (B) further contains an alkyl group-containing silicone (BA) represented by the following formula (6), the surface layer portion formed from the photocatalyst composition of the present invention has a film forming property, hardness, This is preferable because of excellent heat resistance, contamination resistance, chemical resistance, and the like.
R ² _u X _v SiO _{(4-uv) / 2} (6)
(In the formula, each R ² independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Each independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, or a halogen atom. U and v are 0 <u <4, 0 ≦ v <4, and 0 <(u + v) <4.)

Further, as the alkyl group-containing silicone (BA) to be mixed with the phenyl group-containing silicone (BP1), the monooxydiorganosilane unit (D) represented by the formula (7) and the diester represented by the formula (8) are used. When a oxyorganosilane unit (T) having a structure having a molar ratio of preferably (D) / (T) = 100/0 to 5/95, more preferably 90/10 to 10/90 is used. As a result, the stress relaxation action of the alkyl group-containing silicone (BA) is increased, and the crack resistance of the photocatalyst-containing surface layer part produced from the photocatalyst composition (C) of the present invention is improved. As a result, the weather resistance is very excellent. Become.
— (R ² ₂ SiO) — (7)
(In the formula, each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Represents an alkenyl group of

(Wherein R ² is as defined in formula (7).)
In the present invention, in order to improve long-term weather resistance, the binder component (B) preferably forms a phase separation structure, and particularly preferably forms a microphase separation structure.
For example, as the binder component (B), the above-mentioned photocatalyst (a), particularly the binder resin (B ′) having a higher surface energy than the modified photocatalyst (A) and the alkyl group-containing silicone (BA) represented by the above formula (6) ), Preferably in a mass ratio (B ′) / (BA) = 5/95 to 95/5, more preferably (B ′) / (BA) = 30/70 to 90/10 And the photocatalyst-containing surface layer portion formed from the photocatalyst composition (C) of the present invention has a photocatalyst (a) in the binder in which the binder resin (B ′) having a high surface energy and the alkyl group-containing silicone (BA) are phase-separated. Is preferable because it has a dispersed structure and excellent long-term weather resistance.

Here, the phase separation between the binder component (B ′) having a high surface energy and the alkyl group-containing silicone (BA) is preferably a phase that is not a continuous layer, preferably 1 nm ³ to 1 μm ³ , more preferably 10 nm ^{3 to} 0.1 μm ³ , More preferably, a more effective effect can be obtained when a domain having a size of 10 nm ^{3 to} 0.001 μm ³ is formed and microphase separation is performed.
In addition, the state in which the photocatalyst (a) is present in the alkyl group-containing silicone (BA) phase in a phase-separated state with the binder resin (B ′) having a high surface energy is more on the surface of the surface layer portion than the photocatalyst (a). Preferred because it can be present.
As the binder resin (B ′) having a high surface energy that is phase-separated from the alkyl group-containing silicone (BA) in the present invention, the above-mentioned phenyl group-containing silicone (BP) is a siloxane bond (—O—Si—) constituting the skeleton. ) Is preferable because it does not undergo oxidative degradation due to photocatalysis, and phenyl group-containing silicone (BP1) not containing an alkyl group is particularly preferable.

At this time, each of the phenyl group-containing silicone (BP1) and the alkyl group-containing silicone (BA) has a polystyrene-reduced weight average molecular weight measured by GPC, preferably 100 to 10,000, more preferably 500 to 6, 000, more preferably 700 to 4,000, is preferable because the above-described binder component (B) easily forms a microphase separation structure.
The binder component (B) used in the photocatalyst composition (C) of the present invention is any of a type dissolved in a solvent, a type dispersed in a solvent, and a type not mixed with a solvent (liquid or solid). Also good.

In the photocatalyst composition (C) of the present invention, the phenyl group-containing silicone (BP) represented by the above formula (4) does not have a reactive group (X in the formula (4)). The photocatalyst-containing surface layer obtained from the photocatalyst composition (C) of the present invention having a reactive group (X in the formula (4) (that is, 0 <r in the formula (4)). The part is preferable because it is excellent in hardness, heat resistance, chemical resistance, durability and the like. For the same reason, 0 <t in formula (5) and 0 <v in formula (6) are preferable.
In the photocatalyst composition (C) of the present invention, the phenyl group-containing silicone (BP) represented by the above formula (4) has a reactive group (X in the formula (4)) as a hydroxyl group and / or a hydrolyzable group. In the case where it has, a conventionally known hydrolysis catalyst or curing catalyst is preferably added in an amount of 0.01 to 20% by mass, more preferably 0.1 to 5% by mass with respect to the phenyl group-containing silicone (BP). be able to.

The hydrolysis catalyst is preferably an acidic hydrogen halide, a carboxylic acid, a sulfonic acid, an acidic or weakly acidic inorganic salt, or a solid acid such as an ion exchange resin. The amount of the hydrolysis catalyst is preferably in the range of 0.001 to 5 mol with respect to 1 mol of the hydrolyzable group on the silicon atom.
Examples of the curing catalyst include basic compounds such as sodium hydroxide, potassium hydroxide, sodium methylate, sodium acetate, tetramethylammonium chloride, tetramethylammonium hydroxide; tributylamine, diazabicycloundecene, ethylenediamine. Amine compounds such as diethylenetriamine, ethanolamines, γ-aminopropyltrimethoxysilane, γ- (2-aminoethyl) -aminopropyltrimethoxysilane; titanium compounds such as tetraisopropyl titanate, tetrabutyl titanate; Aluminum compounds such as propoxide, aluminum acetylacetonate, aluminum perchlorate, aluminum chloride; tin acetylacetonate, dibutyltin octoate Tin compounds such as tyrates and dibutyltin dilaurate; metal-containing compounds such as cobalt octylate, cobalt acetylacetonate and iron acetylacetonate; acidic such as phosphoric acid, nitric acid, phthalic acid, p-toluenesulfonic acid and trichloroacetic acid Examples thereof include compounds.

  In the photocatalyst composition (C) of the present invention, when the phenyl group-containing silicone (BP) represented by the above formula (4) has a Si—H group, a crosslinking agent such as a polyfunctional alkenyl compound is used for the Si—H group. The alkenyl group is preferably added so that the amount is preferably 0.01 to 2 equivalents, more preferably 0.1 to 1 equivalents. The polyfunctional alkenyl compound may be anything as long as it has an alkenyl group and reacts with the Si—H group to accelerate curing, but has 2 to 30 carbon atoms such as a vinyl group, an allyl group, or a hexenyl group. Alkenyl group-containing silicones having monounsaturated hydrocarbon groups are generally used.

  Further, for the purpose of promoting the reaction between the Si—H group and the polyfunctional alkenyl compound, the catalyst is preferably 1 to 10000 ppm, more preferably 1 to 10000 based on the total amount of the phenyl group-containing silicone (BP) and the polyfunctional alkenyl compound. You may add in the ratio of 1000 ppm. As the catalyst, a platinum group catalyst, that is, a ruthenium, rhodium, palladium, osmium, iridium, or platinum compound is suitable, and a platinum compound and a palladium compound are particularly suitable. Examples of platinum compounds include platinum chloride (II), tetrachloroplatinic acid (II), platinum chloride (IV), hexachloroplatinic acid (IV), hexachloroplatinum (IV) ammonium, hexachloroplatinum (IV) potassium, hydroxide Platinum (II), platinum dioxide (IV), dichloro-dicyclopentadienyl-platinum (II), platinum-vinylsiloxane complex, platinum-phosphine complex, platinum-olefin complex, platinum simple substance, alumina, silica and activated carbon The thing which carry | supported solid platinum is mentioned. Examples of the palladium compound include palladium (II) chloride, ammonium tetraamminepalladium (II) chloride, palladium (II) oxide and the like. The platinum group catalyst is preferably used in an amount of 5 to 1000 ppm in terms of platinum group metal based on the total amount of Si-H group-containing silicone and polyfunctional alkenyl compound. It can be increased / decreased according to the curing rate and the like. Moreover, you may add activity inhibitors, such as various organic nitrogen compounds, an organic phosphorus compound, and an acetylene type compound, for the purpose of suppressing the activity of a platinum group catalyst and extending pot life if desired.

  Further, the photocatalyst composition (C) of the present invention includes silica, alumina, zirconium oxide, antimony oxide, rare earth oxide, etc. for the purpose of improving the hardness, scratch resistance and hydrophilicity of the photocatalyst-containing surface layer portion formed therefrom. The metal oxide fine particles may be added in the form of powder or sol. However, these metal oxide fine particles do not have the ability as a binder like the binder component (B) in the present invention, and reduce the flexibility (flexibility, impact resistance) of the surface layer portion in the same manner as the photocatalyst. Therefore, the addition amount of the metal oxide is preferably such that the total weight of the photocatalyst (a) and the metal oxide is 50% by mass or less in the photocatalyst-containing surface layer formed from the photocatalyst composition (C).

The photocatalyst composition (C) of the present invention may be in a solvent-free state (liquid, solid) or dissolved or dispersed in a solvent, and is not particularly limited, but when used as a coating agent, A dissolved or dispersed state in a solvent is preferred. At this time, the total amount of the modified photocatalyst (A) and the binder component (B) in the photocatalyst composition (C) is preferably 0.01 to 95% by mass, more preferably 0.1 to 70% by mass.
Examples of the solvent used in the photocatalyst composition (C) of the present invention include water, alcohols such as ethylene glycol, butyl cellosolve, isopropanol, n-butanol, ethanol and methanol, aromatic hydrocarbons such as toluene and xylene, hexane, Aliphatic hydrocarbons such as cyclohexane and heptane, esters such as ethyl acetate and n-butyl acetate, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, ethers such as tetrahydrofuran and dioxane, dimethylacetamide, dimethylformamide and the like Examples include amides, halogen compounds such as chloroform, methylene chloride, and carbon tetrachloride, dimethyl sulfoxide, nitrobenzene, and the like. These solvents are used alone or in combination.

In addition, the photocatalyst composition (C) of the present invention usually contains components that are usually added to the paint as necessary, for example, pigments, fillers, dispersants, light stabilizers, wetting agents, thickeners, rheology control agents, An antifoaming agent, a plasticizer, a film forming aid, a rust preventive agent, a dye, a preservative, and the like can be selected, combined and blended depending on the purpose.
In the photocatalyst composition (C) of the present invention, when the self-gradient is very high (that is, on the side of the surface layer portion where the modified photocatalyst (A) content (concentration) is 100, it is not a honeycomb catalyst structure base material. The relative concentration in the vicinity of the surface in contact with the exposed surface is preferably 150 or more, more preferably 200 or more), and the mass ratio of the modified photocatalyst (A) to the binder component (B) in the photocatalyst composition (C) is preferable. (A) / (B) = 0.1 / 99.9 to 40/60, more preferably (A) / (B) = 0.1 / 99.9 to 30/70 of the modified photocatalyst (A) Even in a very low content range, the formed surface layer portion has excellent photocatalytic activity by light irradiation. Further, the surface layer portion having a small photocatalyst content as described above exhibits the original physical properties of the binder component (B), and thus has excellent strength and flexibility (flexibility, impact resistance) and the like.

The honeycomb catalyst structure in the present invention includes a surface layer portion containing a photocatalyst (a) and a binder component (B), and the concentration of the photocatalyst (a) in the surface layer portion increases from the inside of the honeycomb catalyst structure toward the surface. It is characterized by becoming. However, the honeycomb catalyst structure in the present invention can contain the photocatalyst (a) and / or the binder component (B) in a portion other than the surface layer portion, as long as the effects of the present invention are not hindered.
The honeycomb catalyst structure according to the present invention may have a form in which the surface layer is formed into a film, and the film containing the photocatalyst (a) and the binder component (B) is provided on the substrate. By adopting such a form, a structure in which functions are shared between the base material and the surface layer portion becomes possible, which is preferable.

In the honeycomb catalyst structure of the present invention, when the surface layer portion is formed into a film, for example, the photocatalyst composition (C) is applied to the honeycomb catalyst structure substrate and dried, and then preferably 20 ° C. to It can be obtained by forming a film by performing heat treatment at 500 ° C., more preferably 30 ° C. to 250 ° C., ultraviolet irradiation, or the like. Examples of the coating method include spraying, flow coating, roll coating, brush coating, casting, sponge coating, knife coating, gravure coating, screen coating, engraving roll, and the like. -Well-known methods, such as a lucote method, a flexo coat method, or a dipping method, are mentioned.
Under the present circumstances, the film thickness of the film | membrane formed from the photocatalyst composition (C) of this invention becomes like this. Preferably it is 0.1-200 micrometers, More preferably, it is 0.2-20 micrometers, More preferably, it is 0.5-10 micrometers.
At this time, the state of the film may be a continuous film, a discontinuous film, an island-shaped dispersion film, or the like.

The manufacturing method of the honeycomb catalyst structure in the present invention is not limited to the case where a film is formed from the photocatalyst composition of the present invention on a substrate. The base material and the photocatalyst composition of the present invention may be simultaneously processed (for example, integrally processed) into, for example, a fiber, a sheet, or a film. Moreover, you may process a base material, after processing the photocatalyst composition (C) of this invention. Moreover, after processing the photocatalyst composition of this invention and a base material separately, it is good also as a composite by adhesion | attachment, melt | fusion, etc.
Metals such as Ag, Cu, and Zn can be added to the surface layer of the honeycomb catalyst structure of the present invention. The surface layer to which the metal is added can kill bacteria and sputum attached to the surface even in the dark.

  The honeycomb catalyst structure having the photocatalyst surface layer portion of the present invention may have a surface layer portion containing the photocatalyst (a) and the binder component (B) on one side of the honeycomb catalyst structure base material. You may have a surface layer part containing a photocatalyst (a) and a binder component (B) on both surfaces of a structure base material.

  Examples of the substrate that can be used to obtain the honeycomb catalyst structure of the present invention include, for example, a fibrous sheet, a fabric, a metal foil, a resin film, and a laminate of these sheets mainly composed of fibers such as western paper, Japanese paper, and nonwoven fabric. The laminated sheet etc. which were made can be mentioned. Synthetic resins used for the substrate include polyolefin resins such as polyethylene and polypropylene, polyester resins, polyvinyl acetate resins, ethylene vinyl acetate copolymer resins, polyamide resins such as nylon, acrylic resins, and polyvinyl chloride resins. , Polyvinylidene chloride resin, polyvinyl ether resin, polyvinyl ketone resin, polyether resin, polyvinyl alcohol resin, diene resin, and thermoplastic synthetic resin such as polyurethane resin, phenol resin, melamine resin, furan resin, urea resin, In addition to thermosetting synthetic resins such as aniline resins, unsaturated polyester resins, alkyd resins, and epoxy resins, silicon resins and fluorine resins can be used.

  When these synthetic resins are used in the form of fibers, so-called synthetic resin fibers, the cross-sectional shape is not particularly limited, and not only circular but also so-called elliptical, triangular, star-shaped, T-shaped, Y-shaped, and leaf-shaped. An irregular cross-sectional shape may be used. Further, those having voids on the fiber surface, branched structures, and those having a core-sheath structure can be used. Among these synthetic resin fibers, a core-sheath structure mainly having a different softening point from the point that the interfiber bonding strength, flexibility (waistness), processability, etc. when used as a support or an adsorptive photocatalyst sheet can be appropriately controlled. Those having the following are preferred. Examples of the synthetic resin fiber having a core-sheath structure include a fiber in which the core part is made of polyester and the sheath part is made of a polyester copolymer, and a fiber in which the core part is made of polyester and the sheath part is made of polyolefin.

  As natural fibers used for the base material, kraft pulp from softwood and hardwood, sulfite pulp, and chemical pulp such as alkali pulp, semi-chemical pulp, thermomechanical pulp, mechanical pulp, wood fiber such as ground pulp, straw, Examples include non-wood fibers such as Mitsuma, rice, wheat and other straw, hemp, kenaf, bamboo, cotton, cotton linter, bagasse, and esparto. These may be recycled pulp, deinked pulp, or the like made from waste paper. Moreover, as fibers other than the synthetic fiber resin and natural fibers used for the base material, regenerated fibers such as rayon, natural product processed fibers such as cellulose derivative fibers, metal fibers such as steel wool and stainless wool, carbon fibers, ceramic fibers, And various glass fibers.

  The base material according to the present invention is composed mainly of an inorganic material such as an essentially flame-retardant aramid resin, an essentially non-flammable metal, glass, alumina, or the like, if necessary, or a synthetic resin and natural Flame retardancy may be imparted by incorporating a flame retardant into the fiber or the like, or by surface-treating with a flame retardant after forming the substrate.

  In producing the honeycomb catalyst structure according to the present invention, a deodorant such as an adsorbent, an antibacterial agent, an antifungal agent, an antiviral agent, an insect repellent, a pest repellent, and an aromatic agent are used without departing from the spirit of the present invention. Various drugs such as these may be used in combination. As such antibacterial agents, antifungal agents, and antiviral agents, inorganic antibacterial agents mainly composed of silver, zinc, calcium phosphate, etc., organic antibacterials such as benzimidazole, isothiazoline, pyrithione, and chlorohexidine Agents, polymeric antibacterial agents such as chitin and chitosan, catechins extracted from tea and strawberries, bamboo extract extracts, antibacterial agents derived from natural products such as hinokitiol, and hybrid antibacterial agents combining these . Deodorizers are mainly used for the purpose of removing bad odors. Specifically, adsorbents, enzyme-based deodorants such as iron ascorbic acid and metal phthalocyanine derivatives such as iron, cobalt or manganese, manganese-based oxides, Low-temperature oxidation catalyst such as perovskite-type catalyst, synthetic ceramics such as silicon carbide, silicon nitride, calcium silicate, alumina / silica, zirconia, far infrared ceramics such as barley stone and felsong stone, compounds contained in plant extract components Examples include deodorants using certain catechins, tannins, flavonoids, and the like. A plurality of these deodorizers may be used in combination as necessary, or may be a hybrid deodorizer obtained by combining these deodorizers.

As an adsorbent according to the present invention, activated carbon, impregnated activated carbon, activated carbon fiber, natural and synthetic zeolite, activated alumina, activated clay, sepiolite, iron oxide and other iron compounds, zinc oxide, magnesium oxide, silica, silica / zinc oxide Examples include composites, silica / alumina / zinc oxide composites, composite phyllosilicates, ion exchange resins, and mixtures thereof.
Among the adsorbents according to the present invention, a porous substance having a large surface area may function as a carrier for the photocatalyst and is preferable.
The adsorbent according to the present invention is not particularly limited, but is preferably a basic gas adsorbent or an aldehyde adsorbent.

The basic gas adsorbent is an adsorbent mainly containing an acidic substance, specifically, an organic acid such as fumaric acid, maleic acid, acrylic acid, methacrylic acid, crotonic acid, styrene sulfonic acid, alginic acid or the like. Examples thereof include polymers such as multimers, oligomers or polymers, inorganic adsorbents having an acidic group such as activated clay, and acid-added activated carbon to which an acidic substance such as phosphoric acid is added.
The aldehyde adsorbent is an adsorbent having a high affinity with aldehydes such as acetaldehyde and formaldehyde, and examples thereof include amine-impregnated activated carbon, high silica zeolite, and molecular sieve.

  The amine-impregnated activated carbon is activated carbon formed by attaching amines that cause chemical adsorption reaction with various aldehydes. As amines used for amine-impregnated activated carbon, aniline having an amino group as a primary amine compound, benzylamine, naphthylamine, cyclohexylamine, (iso) propanolamine, ethanolamine, diethylenetriamine, triethylenetetramine, styrene ethylamine, styrene Compounds such as amine acrylates, monomers, oligomers, polymers, or derivatives containing amino groups derived from these compounds can be used. Amine compounds other than primary amines, such as ethyl aniline, diethyl amine, methyl vinyl amine, methyl methyl amine styrene acrylate, vinyl benzyl methyl amine, ethyl methyl amine styrene methacrylate, monomers, oligomers, Polymers or secondary amine compounds derived from these compounds, or tertiary amine compounds such as vinylbenzyldimethylamine, vinylbenzyldiethylamine, diethylamine styrene acrylate, diethylamine styrene methacrylate, dimethylamine styrene acrylate, styrene methacrylic acid Dimethylamine, Styrene ethyl methacrylate, Dimethylamine, Styrene ethyl acrylate, Dimethylamine, Styrene ethyl methacrylate Mines, compounds such as ethyl diethylamine styrene acrylate, triethylamine, monomers, oligomers, polymers, or tertiary amine compounds derived from these compounds can also be used, but primary amine compounds having an amino group are preferably used. It is done.

These amine compounds can be adsorbed on activated carbon, or can be converted to amine-immobilized activated carbon by intercalation while partially reacting with functional groups such as hydroxyl groups and alkali metals remaining on the surface of the activated carbon. Although the combination of the amine compound that can be efficiently intercalated and the residual functional group of the activated carbon is limited, the insertion of the amine compound makes it possible to incorporate the aldehyde more firmly into the adsorbent.
The high-silica zeolite according to the present invention is chemically aluminosilicate metal salt crystal like ordinary zeolite, but the ratio of silica to alumina in the crystal is particularly high, and the oxygen atom in the silica structure is basic. Almost no. In such high silica zeolite, the Si-O-Si bond on the surface does not participate in the formation of hydrogen bonds, and since it exhibits hydrophobicity and does not adsorb water molecules, it is efficient even in high humidity and high temperature environments. It is possible to adsorb aldehydes. Thus, high silica zeolite is sometimes called hydrophobic zeolite.

Furthermore, high silica zeolite can adsorb not only aldehydes but also a wide range of odorous substances such as organic acids, ammonia, amines, ketones, sulfur-containing compounds such as hydrogen sulfide and mercaptans, and indoles. Particularly preferred as the adsorbent according to the above.
The honeycomb according to the present invention is a structure composed of cell walls having openings. As a specific example of the honeycomb, a single cardboard produced according to “Exterior Cardboard” described in JIS-Z-1516 is laminated. Corrugated honeycombs, hexagonal cells made of hexagonal cells, honeycombs made of square cells, honeycombs made of triangular cells, and honeycombs made of a collection of hollow cylindrical cells. Here, cell shapes such as hexagons and squares are not regular polygons, but may be irregular shapes such as rounded corners or bent sides.

In the honeycomb catalyst structure of the present invention, corrugated blocks are produced by laminating and adhering single-stage cardboards, and are cut obliquely at a certain angle with respect to the liner surface of the corrugated block. On the other hand, a corrugated honeycomb in which the liner surface has an oblique angle may be used. The oblique angle is not particularly limited, but is preferably 30 to 60 degrees.
The photocatalyst composition (C) according to the present invention may contain a deodorant such as an adsorbent, an antibacterial agent, a pH adjuster, an antioxidant and the like, as long as it does not depart from the gist of the present invention. When irradiating the honeycomb catalyst structure of the present invention with light for exciting the photocatalyst, irradiation may be performed from one side of the opening surface of the honeycomb or from both sides.
The honeycomb catalyst structure of the present invention exhibits photocatalytic activity by irradiating light (excitation light) with energy higher than the band gap energy of the photocatalyst (a) contained in the surface layer portion, and exhibits an excellent effect.

  At this time, the photocatalyst (a) is a triorganosilane unit represented by the above formula (1), a monooxydiorganosilane unit represented by the formula (2), or a dioxyorgano represented by the formula (3). In the case of the modified photocatalyst (A) modified with at least one modifier compound (b) selected from the group consisting of compounds having at least one structural unit selected from the group consisting of silane units, excitation light At least a part of the organic group (R) bonded to the silicon atom of the modifier compound (b) present in the vicinity of the photocatalyst (a) particles by irradiation is substituted with a hydroxyl group by the decomposition action of the photocatalyst. As a result, the hydrophilicity of the coating film surface of the present invention is enhanced, and when the generated hydroxyl groups are subjected to a dehydration condensation reaction to form a siloxane bond, the hardness of the coating film becomes very high. Such a state is preferable in the aspect of the present invention.

Similarly, when the above-mentioned silicone is used as the binder component (B), at least a part of the organic group bonded to the silicon atom of the silicone present in the vicinity of the photocatalyst (a) particles by excitation light irradiation is the photocatalyst. When the hydroxyl group is substituted by the decomposition action, the hydrophilicity of the surface of the surface layer portion of the present invention is increased, and the dehydration condensation reaction between the generated hydroxyl groups proceeds to form a siloxane bond, the hardness of the surface layer portion is very high. Become. Such a state is preferable in the aspect of the present invention.
In the present invention, as a light source having a higher energy than the band gap energy of the photocatalyst (a), in addition to light obtained in a general residential environment such as sunlight and indoor lighting, black light, xenon lamp, mercury lamp, Light such as LED can be used.

The present invention will be specifically described by the following examples, reference examples and comparative examples, but these do not limit the scope of the present invention.
In Examples, Reference Examples and Comparative Examples, various physical properties were measured by the following methods.
1. Particle size distribution and number average particle size The sample was diluted with a suitable solvent so that the photocatalyst content in the sample would be 1 to 20% by mass, and measured using a wet particle size analyzer (Nikkiso Microtrac UPA-9230).

2. Weight average molecular weight It calculated | required by the gel permeation chromatography (GPC) using the analytical curve created using the polystyrene sample.
The conditions for GPC are as follows.
Apparatus: Tosoh HLC-8020 LC-3A type chromatograph column: TSKgel G1000H _XL , TSKgel G2000H _XL, and TSKgel G4000H _XL (all manufactured by Tosoh) were used in series.
-Data processing device: CR-4A type data processing device manufactured by Shimadzu Corporation-Mobile phase:
Tetrahydrofuran (used for analysis of phenyl group-containing silicone)
Toluene (used to analyze silicones that do not contain phenyl groups)
-Flow rate: 1.0 ml / min.
-Sample preparation method It diluted with the solvent used for a mobile phase (concentration was suitably adjusted in the range of 0.5-2 mass%), and used for the analysis.

3. Infrared absorption spectrum The infrared absorption spectrum was measured using a FT / IR-5300 type infrared spectrometer manufactured by JASCO Corporation.
4). Measurement of ²⁹ Si nuclear magnetic resonance Measurement was performed using JNM-LA400 manufactured by JEOL.
5). Surface layer hardness It calculated | required as pencil hardness (scratch of a coating film) according to JIS-K5400.

6). Surface layer hardness after UV irradiation The surface of the sample was irradiated with light of a FL20S BLB type black light manufactured by Toshiba Lighting & Technology for 7 days, and then measured by the above method (5).
At this time, the UV intensity measured using a Topcon UVR-2 type UV intensity meter {using a TOPCON UD-36 type light receiving part (corresponding to light with a wavelength of 310 to 400 nm) as the light receiving part} is 1 mW / cm. ^It was adjusted to be ² .
7). Contact angle of water with respect to sample surface A drop of deionized water was placed on the sample surface and left at 20 ° C. for 1 minute, and then measured using a CA-X150 contact angle meter manufactured by Kyowa Interface Science.
The smaller the water contact angle, the more hydrophilic the sample surface.
8). Change in hydrophilicity (hydrophobicity) of the sample surface before and after ultraviolet irradiation After the surface of the sample was irradiated with ultraviolet rays for 7 days by the method 6 above, the contact angle of water was measured by the method 7 above.

9. Photocatalytic activity of the sample A 5 wt% ethanol solution of methylene blue was applied to the surface of the sample, and then irradiated with ultraviolet rays for 5 days by the above method 6.
Thereafter, based on the degree of decomposition of methylene blue by the action of the photocatalyst (visually evaluated based on the degree of fading of the surface of the sample), the activity of the photocatalyst was evaluated in the following three stages.
A: Methylene blue is completely decomposed.
Δ: Slightly methylene blue blue remains.
X: Methylene blue was hardly decomposed.

10. Weather resistance (gloss retention)
An exposure test (irradiation: 60 ° C. for 4 hours, dark / wet: 40 ° C. for 4 hours) was performed using a DPWL-5R type dew panel light control weather meter manufactured by Suga Test Instruments. The 60 ° -60 ° specular reflectance after 1000 hours of exposure was measured as the final gloss value, divided by the initial gloss value, and this value was calculated as the gloss retention.

11. Evaluation of inclined structure of photocatalyst After embedding the sample in an epoxy resin (Quetol 812), an ultrathin section having a thickness of 50 to 60 nm was prepared with a ULTRACUT-N type microtome manufactured by Reichert, Germany, and applied to a mesh with a supporting film. Loaded. Subsequently, RuO4 vapor staining was performed for about 5 minutes, and then carbon deposition was performed to obtain a spectroscopic sample, and the cross section of the coating film was observed by TEM.
The conditions for TEM observation are as follows.
・ Device: Hitachi HF2000 type ・ Acceleration voltage: 125kV
The location of photocatalytic titanium oxide was analyzed by EDX analysis of Ti element.
In addition, observation of the film formed on the aluminum plate having the acrylic urethane base coat layer was performed by roughly cutting the sample with a DAD321 type dicing saw manufactured by DISCO Engineering Service, performing FIB (Focused Ion Beam) processing, and using TEM Observation of the cross section of the film was performed.

The FIB processing conditions are as follows.
Equipment used: Hitachi FB2000 machining conditions: Acceleration voltage (30 kV)
Ion source: Ga
The conditions for TEM observation are as follows.
・ Device: Hitachi HF2000 ・ Acceleration voltage: 200kV

12 Impact resistance In accordance with JIS-K5400, the DuPont type (500 g x 50 cm) was evaluated.
13. Deodorizing property A sample cut into 5cm x 1cm is put into a 120ml glass bottle, acetaldehyde is injected in an amount that makes the gas concentration in the bottle 1000ppm, and light of FL20SBLB type black light made by Toshiba Lighting & Technology is irradiated from the outside for 4 hours. After that, the air in the bottle was measured with a gas chromatograph G3800 (detector FID) manufactured by Yanagimoto Seisakusho.
At this time, the UV intensity measured using a Topcon UVR-2 type UV intensity meter {using a TOPCON UD-36 type light receiving part (corresponding to light with a wavelength of 310 to 400 nm) as the light receiving part} is ² mW / cm ^2. It adjusted so that it might become.

14 Contamination resistance A sample cut into 5 cm x 1 cm is placed in a 120 ml glass bottle, filled with 5 cigarettes of smoke, and a sample of cigarette smoke is attached to the sample. The sample was irradiated with light for 4 hours, and the antifouling property was evaluated in the following three stages based on the appearance (visual evaluation) of the sample.
At this time, the UV intensity measured using a Topcon UVR-2 type UV intensity meter {using a TOPCON UD-36 type light receiving part (corresponding to light with a wavelength of 310 to 400 nm) as the light receiving part} is ² mW / cm ^2. It adjusted so that it might become.
○: Coloring due to cigarette dust completely disappeared △: Coloring due to cigarette dust becomes light ×: No change in coloring due to cigarette dust

15. Light Resistance After irradiating the sample with light of FL20S BLB type black light manufactured by Toshiba Lighting & Technology for 30 days, light resistance was evaluated in the following three stages based on the appearance (visual evaluation) of the sample.
At this time, the UV intensity measured using a Topcon UVR-2 type UV intensity meter {using a TOPCON UD-36 type light receiving part (corresponding to light with a wavelength of 310 to 400 nm) as the light receiving part} is ² mW / cm ^2. It adjusted so that it might become.
○: No change in appearance △: Photocatalyst layer peeling ×: Paper is decomposed

[Reference Example 1]
Synthesis of phenyl group-containing silicone (BP1-1).
After 26.0 g of phenyltrichlorosilane was added to 78 g of dioxane in a reactor having a reflux condenser, a thermometer, and a stirring device, the mixture was stirred at room temperature for about 10 minutes. A mixture of 3.2 g of water and 12.9 g of dioxane was added dropwise thereto over about 30 minutes while maintaining the reaction solution at 10 to 15 ° C., followed by further stirring at 10 to 15 ° C. for about 30 minutes, The reaction solution was heated to 60 ° C. and stirred for 3 hours. The resulting reaction solution was cooled to 25-30 ° C., 392 g of toluene was added dropwise over about 30 minutes, and then the reaction solution was again heated to 60 ° C. and stirred for 2 hours.

The resulting reaction solution was cooled to 10 to 15 ° C., and 19.2 g of methanol was added over about 30 minutes. Thereafter, stirring was further continued at 25 to 30 ° C. for about 2 hours, and then the reaction solution was heated to 60 ° C. and stirred for 2 hours. The solvent was distilled off from the resulting reaction solution at 60 ° C. under reduced pressure to obtain a phenyl group-containing silicone (BP1-1) having a ladder skeleton having a weight average molecular weight of 3600. (In the obtained phenyl group-containing silicone (BP1-1), absorptions (1130 cm ⁻¹ and 1037 cm ⁻¹ ) derived from the stretching vibration of the ladder skeleton in the IR spectrum were observed.)
^Further, 29 wherein the Si-nuclear magnetic resonance measurement results from the phenyl group-containing silicone obtained (BP1-1) _{was (Ph) 1 (OCH 3)} 0.58 SiO 1.21. (Here, Ph represents a phenyl group.)

[Reference Example 2]
Synthesis of alkyl group-containing silicone (BA-1).
After adding 136 g (1 mol) of methyltrimethoxysilane and 120 g (1 mol) of dimethyldimethoxysilane to 300 g of methanol in a reactor having a reflux condenser, a thermometer and a stirring device, the mixture was stirred at room temperature for about 10 minutes. did. Under ice cooling, a mixture of 12.6 g (0.7 mol) of 0.05N aqueous hydrochloric acid and 63 g of methanol was added dropwise over about 40 minutes for hydrolysis. After completion of the dropwise addition, the mixture was further stirred at 10 ° C. or lower for about 20 minutes and at room temperature for 6 hours.

Then, the alkyl group containing silicone (BA-1) of the weight average molecular weight 3600 was obtained by distilling a solvent off from the obtained reaction liquid under reduced pressure at 60 degreeC. When the structure of the obtained alkyl group-containing silicone (BA-1) was measured by ²⁹ Si nuclear magnetic resonance, signals indicating T structure and D structure were confirmed, and the ratio was T structure: D structure = 1: 1. there were.
^The average composition formula of the above alkyl group-containing silicone obtained from the measurement results of 29 Si nuclear magnetic resonance (BA-1) _{was (CH 3) 1.5 (OCH 3} ) 0.27 SiO 1.12 .

[Reference Example 3]
Adjustment of silicone composition (B-1).
To a mixture of 6 g of the phenyl group-containing silicone (BP1-1) synthesized in Reference Example 1 and 3 g of the alkyl group-containing silicone (BA-1) synthesized in Reference Example 2, 14.7 g of toluene, 29.8 g of isopropanol, and butyl cellosolve 15.1g was added and the solution of the binder component (B-1) was obtained by stirring at room temperature.
From the average composition formula of each composition, the average composition formula of the binder component (B-1) is (Ph) _0.67 (CH ₃ ) _0.5 (OCH ₃ ) _0.47 SiO _1.18. Can be calculated. (Here, Ph represents a phenyl group.)

[Reference Example 4]
TKS-251 {trade name of titanium oxide organosol (manufactured by Teica), dispersion medium: mixed solvent of toluene and isopropanol, TiO2 concentration 20% by weight, average crystal in a reactor having a reflux condenser, a thermometer and a stirrer By adding 40 g of a 20 wt% toluene solution of bis (trimethylsiloxy) methylsilane to 50 g of a 6 nm diameter (catalog value) over about 5 minutes and further stirring at 50 ° C. for 12 hours, A modified photocatalyst organosol (A-1) having good dispersibility was obtained. At this time, the amount of hydrogen gas produced by the reaction of bis (trimethylsiloxy) methylsilane was 718 ml at 23 ° C. Moreover, when the obtained modified titanium oxide organosol was coated on a KBr plate and IR spectrum was measured, disappearance of absorption of Ti—OH group (3630 to 3640 cm ⁻¹ ) was observed.

1 and 2 show the particle size distributions of TKS-251 before the modification treatment and the obtained modified photocatalyst organosol (A-1), respectively. The resulting modified photocatalyst organosol (A-1) has a single particle size distribution (number average particle size is 25 nm), and further a single dispersion of TKS-251 before the modification treatment (number average particle size is 12 nm). As can be seen from FIG.
Subsequently, 20 g of the modified photocatalyst organosol (A-1) was added to 68 g of the solution of the silicone component (B-1) prepared in Reference Example 3 at room temperature with stirring, and a curing catalyst (dibutyltin dilaurate) 0 .5 g was added with stirring to obtain a photocatalyst composition (C-1).

  Spray a 1mm thick aluminum plate (JIS, H, 4000 (A1050P)) cut to 50mm x 60mm with Mighty Rack White {trade name of acrylic urethane resin paint (two-component mixed type)} (manufactured by Nippon Paint)} And dried at room temperature for 3 days. After spray-coating the photocatalyst composition (C-1) on the obtained aluminum plate coated with acrylic urethane so as to have a film thickness of 2 μm, it is dried at room temperature for 1 hour and heated at 150 ° C. for 30 minutes. Thus, a test plate (D-1) having a photocatalytic film was obtained.

  The test plate (D-1) having the obtained photocatalyst film was subjected to FIB processing, and the result of observation of the film cross section by TEM is shown in the photograph of FIG. Moreover, the illustration of the photograph of Fig.3 (a) is FIG.3 (b). A photocatalytic film (indicated by reference numeral 2 in FIG. 3B) containing modified photocatalyst particles (indicated by reference numeral 1 in FIG. 3B), and pigment titanium oxide (FIG. 3B in FIG. 3B). ), The modified photocatalyst particles are not present at the interface with the acrylic urethane film (indicated by reference numeral 3 in FIG. 3 (b)) including the modified photocatalyst particles. It was observed that it was covered.

The test plate (D-1) having the photocatalyst film thus obtained had a pencil hardness of H and a contact angle with water of 105 °. Moreover, the impact resistance test passed.
The test plate (D-1) having the photocatalyst film obtained had a pencil hardness of 5H or higher after irradiation with ultraviolet light (black light) and a water contact angle of 0 °. Furthermore, the photocatalytic activity evaluation result was also very good (良好).
Furthermore, the gloss retention by an exposure test (after 1000 hours) using a dew panel light control weather meter was 98%, indicating very good weather resistance.
Subsequently, the photocatalyst composition (C-1) was spray-coated on an epoxy resin (Quetol 812), dried at room temperature for 2 days, and then heated at 50 ° C. for 3 days to provide an epoxy having a smooth photocatalyst film. Resin (D-2) was obtained.

After embedding the obtained epoxy resin (D-2) having a photocatalytic film in an epoxy resin (Quetol 812), an ultrathin section having a thickness of 50 to 60 nm was prepared by a microtome, and phenyl group-containing silicone (BP1) was formed using RuO _4. The result of having observed the film cross section by TEM after dye | staining -1) is shown to the photograph of Fig.4 (a). Moreover, the illustration of the photograph of Fig.4 (a) is FIG.4 (b).
A photocatalyst film (indicated by reference numeral 2 in FIG. 4 (b)) containing modified photocatalyst particles (indicated by reference numeral 1 in FIG. 4 (b)) and an epoxy resin (in FIG. 4 (b)). It was observed that almost no modified photocatalyst particles were present at the interface with the reference number 5), and the entire surface of the photocatalyst film was covered with the modified photocatalyst particles.

4B is a boundary portion between the modified photocatalyst particle phase 1 and the binder phase 7 not containing the modified photocatalyst particles, and an enlarged photograph of the portion is shown in FIG. (A). Moreover, the illustration of the photograph of Fig.5 (a) is FIG.5 (b).
FIG. 5A shows a binder phase containing modified photocatalyst particles (indicated by reference numeral 1 in FIG. 5B) and a binder phase not containing modified photocatalyst particles (reference numeral 7 in FIG. 5B). Can be observed. In the binder phase not containing the modified photocatalyst particles (indicated by reference numeral 7 in FIG. 5B), the phenyl group-containing silicone dyed with RuO ₄ and the undyed alkyl group-containing silicone are composed of a microphase-separated structure. It can be observed that it exists.

[Reference Example 5]
A photocatalyst composition (C-2) was obtained in the same manner as in Reference Example 4 except that 10 g of unmodified TKS-251 was used instead of 20 g of the modified photocatalyst organosol (A-1).
Using the resulting photocatalyst composition (C-2), the same operation as in Reference Example 4 was performed to obtain a test plate (D-3) having a photocatalyst film (titanium oxide content is the same as in Reference Example 4). .
The test plate (D-3) having the obtained photocatalyst film had a pencil hardness of H and a contact angle with water of 97 °.

Further, the test plate (D-3) having the photocatalytic film thus obtained had a pencil hardness of 3H after irradiation with ultraviolet light (black light) and a water contact angle of 94 °. Furthermore, the photocatalytic activity evaluation was a bad result (x).
Further, in a 200-hour exposure test using a dew panel light control weather meter, the gloss retention was 10% or less, and a choking phenomenon was observed.
Subsequently, the photocatalyst composition (C-2) is spray-coated on an epoxy resin (Quetol 812), dried at room temperature for 2 days, and then heated at 50 ° C. for 3 days to have a smooth photocatalyst film. An epoxy resin (D-4) was obtained.
After embedding the obtained epoxy resin (D-4) having a photocatalytic film in an epoxy resin (Quetol 812), an ultrathin section having a thickness of 50 to 60 nm was prepared by a microtome, and phenyl group-containing silicone (BP1) was formed using RuO _4. The result of having observed the film cross section by TEM after dye | staining -1) is shown to the photograph of Fig.6 (a). FIG. 6B is an illustration of the photograph of FIG.

  A photocatalyst film (indicated by reference numeral 2 in FIG. 6B) containing modified photocatalyst particles (indicated by reference numeral 1 in FIG. 6B), and an epoxy resin (in FIG. 6B). The photocatalyst film has a large amount of modified photocatalyst particles at the interface with the alkyl group-containing silicone in which all the exposed surface of the photocatalyst film is not present (indicated by reference numeral 8 in FIG. 6B). It was observed that the photocatalytic activity could not be expected.

[Example 1]
The photocatalyst composition (C-1) prepared in Reference Example 4 was applied to paper so that the dry film thickness was about 3 μm, heat-treated at 150 ° C. for 10 minutes, and then light of FL20SBLB type black light manufactured by Toshiba Lighting & Technology [ Adjusted so that the UV intensity measured using a Topcon UVR-2 UV intensity meter (light receiving part: UD-36 light receiving part made by Topcon) was adjusted to ² mW / cm ² ]. . About the obtained photocatalyst carrying paper, the piece corrugated cardboard which bonded the liner and liner of 2.5mm of pitch produced based on JISZ1516-1995 "corrugated cardboard for exterior" is laminated, and it is 100mm x 100mm x thickness 10mm A honeycomb-shaped photocatalyst member sample (E-1) was prepared.
When the deodorizing property of this sample (E-1) was evaluated, 200 ppm of acetaldehyde became 5 ppm after irradiation with ultraviolet rays (black light). Further, the contamination resistance was very good (◯). Furthermore, the light resistance of this sample (E-1) was also good (◯).
Further, when the deodorizing property of the sample (E-1) after the light resistance test was evaluated, 200 ppm of acetaldehyde became 7 ppm after irradiation with ultraviolet rays (black light), and the performance was maintained. Further, the contamination resistance was very good (◯).

[Comparative Example 1]
When the deodorizing property of the sample (E-2) prepared by the same method as in Example 1 was evaluated using untreated paper, 200 ppm of acetaldehyde was almost unchanged at 190 ppm even after irradiation with ultraviolet rays (black light). . Further, the contamination resistance was a bad result (x). The light resistance was good (◯).

[Comparative Example 2]
A honeycomb-shaped photocatalyst member sample was prepared in the same manner as in Example 1 except that the photocatalyst composition (C-2) prepared in Reference Example 5 was used instead of the photocatalyst composition (C-1) prepared in Reference Example 4. (E-3) was obtained.
When the deodorizing property of this sample (E-3) was evaluated, 200 ppm of acetaldehyde was hardly changed to 190 ppm even after irradiation with ultraviolet rays (black light). Moreover, the result (x) with bad pollution resistance was also bad. Furthermore, the light resistance of this sample (E-3) was also poor (x).

[Comparative Example 3]
The same procedure as in Example 1 was performed except that ST-K03 (manufactured by Ishihara Sangyo Co., Ltd.), which is a commercially available photocatalyst coating solution, was used instead of the photocatalyst composition (C-1) prepared in Reference Example 4, and the honeycomb A photocatalyst member sample (E-4) was obtained.
However, the photocatalyst-containing film of this sample (E-4) was cracked by drying and dropped out of the honeycomb, so that the physical properties could not be evaluated.

[Comparative Example 4]
Instead of the photocatalyst composition (C-1) prepared in Reference Example 4, a commercially available photocatalyst coating solution ST? K03 (manufactured by Ishihara Sangyo Co., Ltd.) is used so that the dry film thickness is about 0.3 μm. Except for being applied to the sample, the same procedure as in Example 1 was performed to obtain a honeycomb-shaped photocatalyst member sample (E-5).
When the deodorizing property of this sample (E-5) was evaluated, 200 ppm of acetaldehyde became 10 ppm after irradiation with ultraviolet rays (black light). In addition, although the contamination resistance was a good result (◯), the light resistance was a bad result (×).

The honeycomb catalyst structure of the present invention decomposes organic substances using a photocatalytic function, thereby deodorizing or detoxifying harmful pollutants, removing NO _x , SO _x , CO _2, etc. in the environment, decoloring dyeing waste water, It can be suitably used in fields such as water purification.

FIG. 1 is a graph showing the results of measuring the particle size distribution of TKS251 (commercially available titanium oxide organosol) before modification using a wet particle size analyzer. FIG. 2 is a view showing the results of measuring the particle size distribution of the modified photocatalyst organosol (A-1) obtained by modifying TKS-251 in Reference Example 4 using a wet particle size analyzer. . FIG. 3A is a TEM photograph of a cross section of the test plate (D-1) having the photocatalyst-containing coating obtained in Reference Example 4. FIG. 3B is an illustration of FIG. 4A is a TEM photograph of a cross section of an epoxy resin (D-2) having a photocatalyst-containing film obtained in Reference Example 4. FIG. FIG. 4B is an illustration of FIG. Fig.5 (a) is the photograph which expanded a part of TEM photograph of Fig.4 (a). FIG. 5B is an illustration of FIG. 6A is a TEM photograph of a cross section of an epoxy resin (D-3) having a photocatalyst-containing film obtained in Reference Example 5. FIG.

  FIG. 6B is an illustration of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Modified photocatalyst particle 2 Photocatalyst containing film | membrane 3 Acrylic urethane film | membrane 4 Titanium oxide which is a pigment 5 Epoxy resin 5 (b) The enlarged view in the boundary part of the modified photocatalyst particle phase 1 and the binder phase 7 which does not contain modified photocatalyst particles 5 (b) 6 embedded epoxy resin 7 binder phase not containing modified photocatalyst particles 8 alkyl group-containing silicone

Claims (18)

  A honeycomb catalyst structure having a surface layer portion containing a photocatalyst (a) and a binder component (B), wherein the concentration of the photocatalyst (a) in the surface layer portion increases from the inner side to the surface of the honeycomb catalyst structure. A honeycomb catalyst structure characterized by comprising:   The surface layer portion is in the form of a film, and the concentration of the photocatalyst (a) in the film increases from the surface in contact with the substrate of the honeycomb catalyst structure toward the other exposed surface. The honeycomb catalyst structure according to the description.   The honeycomb catalyst structure according to claim 1 or 2, wherein the surface layer portion is formed from a photocatalyst composition (C) containing a photocatalyst (a) and a binder component (B). The photocatalyst (a) is a triorganosilane unit represented by the formula (1), a monooxydiorganosilane unit represented by the formula (2), a dioxyorganosilane unit represented by the formula (3), and Modified photocatalyst modified with at least one modifier compound (b) selected from the group consisting of compounds having at least one structural unit selected from the group consisting of methylene fluoride (—CF ₂ —) units ( The honeycomb catalyst structure according to any one of claims 1 to 3, wherein the honeycomb catalyst structure is A).
R ₃ Si- (1)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group)
_{- (R 2 SiO) - (} 2)
(In the formula, R is as defined in formula (1).)
(In the formula, R is as defined in formula (1).) The honeycomb catalyst structure according to any one of claims 1 to 4, wherein the binder component (B) contains a phenyl group-containing silicone (BP) represented by the following formula (4).
^{_{R 1 p R 2 q X r}} SiO (4-p-q-r) / 2 (4)
(In the formula, each R ¹ represents a phenyl group, and each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or Represents a branched alkenyl group having 2 to 30 carbon atoms;
X represents a hydrogen atom, a hydroxyl group, a C1-C20 alkoxy group, a C1-C20 acyloxy group, an aminoxy group, a C1-C20 oxime group, and a halogen atom each independently. And p, q, and r are 0 <p <4, 0 ≦ q <4, 0 ≦ r <4, and 0 <(p + q + r) <4, and 0.05 ≦ p / (p + q) ≦ 1 is there. ) The honeycomb catalyst structure according to claim 5, wherein the phenyl group-containing silicone (BP) is a phenyl group-containing silicone (BP1) not containing an alkyl group, represented by the following formula (5).
^{_{R 1 s X t SiO (4}} -s-t) / 2 (5)
(Wherein R ¹ represents a phenyl group. X is independently a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or an oxime having 1 to 20 carbon atoms. Group represents a halogen atom, and s and t are 0 <s <4, 0 ≦ t <4, and 0 <(s + t) <4.) The honeycomb catalyst structure according to any one of claims 5 and 6, wherein the binder component (B) further contains an alkyl group-containing silicone (BA) represented by the following formula (6).
R ² _u X _v SiO _{(4-uv) / 2} (6)
(In the formula, each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Each independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, or a halogen atom. And u and v are 0 <u <4, 0 ≦ v <4, and 0 <(u + v) <4.) The binder component (B) contains a phenyl group-containing silicone (BP1) not containing an alkyl group represented by formula (5) and an alkyl group-containing silicone (BA) represented by formula (6). The honeycomb catalyst structure according to any one of claims 1 to 4, wherein
^{_{R 1 s X t SiO (4}} -s-t) / 2 (5)
(Wherein, R ¹ represents a phenyl group, and each X independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, or an oxime having 1 to 20 carbon atoms. Group represents a halogen atom, s and t are 0 <s <4, 0 ≦ t <4, and 0 <(s + t) <4.
R ² _u X _v SiO _{(4-uv) / 2} (6)
(In the formula, each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Each independently represents a hydrogen atom, a hydroxyl group, an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 20 carbon atoms, an aminoxy group, an oxime group having 1 to 20 carbon atoms, or a halogen atom. Represent.
u and v are 0 <u <4, 0 ≦ v <4, and 0 <(u + v) <4. ) The alkyl group-containing silicone (BA) has a monooxydiorganosilane unit (D) represented by the formula (7) and a dioxyorganosilane unit (T) represented by the formula (8). The honeycomb catalyst structure according to claim 7 or 8.
— (R ² ₂ SiO) — (7)
(In the formula, each R ² is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 2 to 30 carbon atoms. Represents an alkenyl group of
(Wherein R ² is as defined in formula (7).)   The honeycomb catalyst structure according to any one of claims 7 to 9, which is a surface layer portion having a phase separation structure for the phenyl group-containing silicone (BP) and the alkyl group-containing silicone (BA).   The honeycomb catalyst structure according to claim 10, wherein the photocatalyst (a) is present in the alkyl group-containing silicone (BA) phase.   The honeycomb catalyst structure according to claim 3, wherein the number average particle diameter of the photocatalyst (a) is 400 nm or less. The honeycomb catalyst structure according to claim 4, wherein the modifier compound (b) is a Si-H group-containing silicon compound (b1) represented by the formula (9).
H _x R _y SiO _{(4-xy) / 2} (9)
(In the formula, each R is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon group having 1 to 30 carbon atoms. A fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, a phenyl group, an alkoxy group having 1 to 20 carbon atoms, or a hydroxyl group, where x and y are 0 <x <4, 0 <Y <4 and (x + y) ≦ 4.) The Si-H group-containing silicon compound (b1) is a mono-Si-H group-containing compound represented by the formula (10), a Si-H group-containing compound represented by the formula (11), a formula (12) The honeycomb catalyst structure according to claim 13, wherein the honeycomb catalyst structure is at least one compound selected from the group consisting of H silicones represented by:
(In the formula, each R ³ independently represents a linear or branched alkyl group having 1 to 30 carbon atoms, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a carbon number of 5 to 20). A cycloalkyl group, a linear or branched fluoroalkyl group having 1 to 30 carbon atoms, a phenyl group, or a siloxy group represented by the formula (13).
—O— (R ⁴ ₂ SiO) _m —SiR ⁴ ₃ (13)
(In the formula, each R ⁴ is independently a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched carbon number of 1 to 1. 30 represents a fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, or a phenyl group, and m is an integer and 0 ≦ m ≦ 1000.)
H— (R ³ ₂ SiO) _n —SiR ³ ₂ —H (11)
(In the formula, R ³ is as defined in formula (10). N is an integer and 0 ≦ n ≦ 1000.)
(R ³ HSiO) _a (R ³ ₂ SiO) _b (R ³ ₃ SiO _1/2 ) _c (12)
(Wherein R ³ is as defined in formula (10), a is an integer of 1 or more, b is an integer of 0 or more, (a + b) ≦ 10000, and c is 0 or 2) Provided that when (a + b) is an integer of 2 or more and c = 0, the H silicone of the formula (12) is a cyclic silicone, and when c = 2, the H silicone of the formula (12) Is a chain silicone.)   The honeycomb catalyst structure according to claim 1 or 2, wherein the binder component (B) in the surface layer part forms a phase separation structure.   The honeycomb catalyst structure according to claim 1 or 2, which exhibits photocatalytic activity and / or hydrophilicity when irradiated with light having energy higher than the band gap energy of the photocatalyst (a) contained in the surface layer portion. body.   By irradiating light having energy higher than the band gap energy of the photocatalyst (a) contained in the surface layer portion, at least a part of the organic groups bonded to the silicon atoms existing in the vicinity of the photocatalyst (a) particles are hydroxyl groups. The honeycomb catalyst structure according to any one of claims 4, 5, 7, and 8, wherein the honeycomb catalyst structure is substituted with a siloxane bond.   A photocatalyst composition (C) comprising a photocatalyst (a) and a binder component (B), wherein the surface layer portion according to claim 1 is formed.