JP2006116449A - Photocatalyst fiber and porous photocatalyst fiber derived from it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a porous photocatalyst fiber having an excellent effect of decomposing and removing environmental pollutants, an excellent antifouling effect and excellent durability of the effects and a photocatalyst fiber serving as a precursor for the porous photocatalyst fiber. <P>SOLUTION: The photocatalyst fiber contains a photocatalyst (a) and increases in the BET surface area by 0.1 m<SP>2</SP>/g or more when irradiated with light. A porous photocatalyst fiber derived from the photocatalyst fiber is also provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a photocatalyst fiber, a porous photocatalyst fiber derived from the photocatalytic activity and / or highly hydrophilic for a long period of time, and a processed body of the porous photocatalyst fiber.
Specifically, the present invention is useful for the decomposition, removal and sterilization of various malodorous gases, harmful gases, harmful compounds, etc. generated in daily life over a long period of time, fungicides, etc. The present invention relates to a porous photocatalyst fiber that can be decomposed and maintain the appearance of its appearance, and can easily remove sebum stains by washing or washing with water, and a processed body of the porous photocatalyst fiber.

For certain substances, light having an energy larger than the energy gap (band gap) between the conduction band and valence band of the substance, that is, light having a shorter wavelength than light corresponding to the band gap of the substance ( When excitation light is irradiated, excitation of electrons in the valence band (photoexcitation) occurs by light energy, and electrons are generated in the conduction band and holes are generated in the valence band. At this time, various chemical reactions can be performed using the reducing power of electrons generated in the conduction band and / or the oxidizing power of holes generated in the valence band.
That is, the above substances can be used like a catalyst under excitation light irradiation. Therefore, the above substances are called photocatalysts, and titanium oxide is known as the most typical example.
Examples of chemical reactions promoted by this photocatalyst include oxidative decomposition reactions of various organic substances. Therefore, if this photocatalyst is immobilized on the surface of various base materials, various organic substances adhering to the surface of the base material can be oxidatively decomposed using light energy.

In recent years, research has been actively conducted to apply the characteristics of the above photocatalysts to various fields such as environmental purification, deodorization, antibacterial, antifouling of various base materials and prevention of mold. It has become to.
In this case, when the photocatalytic activity is actually used for the purpose of decomposing and sterilizing harmful gases such as harmful gases in exhaust gas, odorous gases such as cigarettes and toilets, pesticides, environmental pollutants, etc. Therefore, it is necessary to support and fix on a certain substrate such as a fiber instead of a powder form.

Conventionally, when a photocatalyst such as titanium dioxide is supported on a fiber, the photocatalyst is often directly supported on the fiber surface. However, this method has a drawback that the fiber itself is decomposed by the decomposition action of the photocatalyst.
For the purpose of improving these, for example, as a method of adding titanium dioxide for photocatalyst to a fiber, a method in which titanium dioxide particles are aggregated, a method in which titanium dioxide particles are supported on inorganic particles such as activated carbon, and titanium dioxide particles in silica A method of coating with an inorganic material such as alumina or alumina has been proposed.
These methods attempt to improve the decomposition of the fiber by reducing the contact point between the titanium dioxide particles and the fiber, but the decomposition proceeds at the contact point between the fiber and the titanium dioxide particles, and the effect is not sufficient. Moreover, while the activity of titanium dioxide particles is greatly reduced by the coating, there remains a problem that a great deal of labor is required to perform these treatments and processing.

In addition, a method of causing a photocatalyst to be present on the fiber surface by applying a paint having a photocatalyst to the fiber surface has been studied, but when the photocatalyst and the resin are mixed and applied to the fiber surface, the surface of the photocatalyst is applied to the resin. There was the subject that it was covered and the effect cannot be fully demonstrated.
The above-mentioned problems are common to all photocatalysts other than titanium dioxide, as well as highly active substances such as adsorbents and bactericides. When these highly active substances are put to practical use, the strength is not reduced. A fixing method that is excellent in cost, inexpensive and easy to handle has been desired.
In response to these problems, for example, in JP-A-9-613, a resin layer is formed on the surface of a substrate such as paper for the purpose of protecting the substrate such as fiber from the decomposition action of the photocatalyst, and silica is formed thereon. There has been proposed a method of forming a photocatalyst-containing film on the film after forming the film.
However, in this method, the coating process is complicated, the workability is poor, the production loss is increased, and the cost is increased. Therefore, a paper provided with a photocatalyst-containing film that does not require a protective layer has long been desired.

Japanese Patent Laid-Open No. 10-237794 proposes that a fiber directly provided with a silica film containing a photocatalyst can balance photocatalytic activity and weather resistance more than expected, but has a conventional photocatalyst. Although the performance is improved over the method of applying a paint, the weather resistance is insufficient when trying to develop a large photocatalytic activity, and conversely, if it is attempted to improve the weather resistance, it is necessary to sacrifice the photocatalytic activity, The conventional problem has not been solved completely.
JP-A-9-613 JP-A-10-237794

  The object of the present invention is to solve the above-mentioned problems. A porous photocatalyst fiber that exhibits photocatalytic activity such as fungicidal, algicidal effect, and further prevents the fiber itself from being soiled, and maintains the performance for a long period of time, and a photocatalyst fiber product using the porous photocatalyst fiber, for example, It is to provide antibacterial agents and deodorants.

As a result of intensive studies, the present inventors have made the present invention. That is, the present invention is as follows.
1. A photocatalyst fiber containing a photocatalyst (a), wherein the BET surface area is increased by 0.1 m ² / g or more by light irradiation.
2. The photocatalyst fiber of Invention 1, wherein the BET surface area per 1 g of the photocatalyst (a) contained by light irradiation increases by 10 m ² or more.
3. A composite compound (BC) in which a photocatalyst (a), a photocatalytic affinity organic component (B) that has a strong affinity for the photocatalyst and is decomposed by photocatalysis, and a hardly decomposable component (C) that is not easily decomposed by photocatalysis The photocatalyst fiber of the invention 1 characterized by comprising
4). A composite compound (BC) in which the photocatalyst (a) has a strong affinity for the photocatalyst and is combined with a photocatalytic affinity organic component (B) that is decomposed by photocatalysis and a hardly decomposable component (C) that is not easily decomposed by photocatalysis. The photocatalyst fiber of the invention 1 which contains the modified photocatalyst (A) obtained by modification treatment with
5. The photocatalytic fiber according to any one of Inventions 3 and 4, wherein the photocatalytic affinity organic component (B) has a polyoxyalkylene group.
6). The photocatalyst fiber according to any one of inventions 1 to 5, wherein the photocatalyst (a) is a visible light responsive photocatalyst.
7). The photocatalyst fiber according to any one of inventions 1 to 6, comprising a sensitizing dye.
8). The porous photocatalyst fiber whose BET surface area increased 0.1 m < ² > / g or more by irradiating the photocatalyst fiber in any one of invention 1-6 with the light of energy higher than the band gap energy of the photocatalyst (a) to contain.
9. The porous photocatalyst fiber whose BET surface area increased by 0.1 m < ² > / g or more by irradiating the photocatalyst fiber of invention 7 with the absorption light of the contained sensitizing dye.

10. The porous photocatalyst fiber according to any one of Inventions 8 and 9, which has an organic matter decomposing activity.
11. The porous photocatalyst fiber according to any one of Inventions 8 and 9, which has antibacterial performance.
12 The porous photocatalyst fiber according to any one of Inventions 8 and 9, characterized by having antifungal performance.
13. The porous photocatalyst fiber according to any one of Inventions 8 and 9, wherein the moisture absorption is 5 to 30%.
14 A fabric comprising the porous photocatalytic fiber of inventions 8 and 9.
15. A woven fabric comprising the porous photocatalytic fiber of inventions 8 and 9.
16. A knitted fabric comprising the porous photocatalytic fiber of inventions 8 and 9.
17. A nonwoven fabric comprising the porous photocatalytic fiber of inventions 8 and 9.
18. Paper containing the porous photocatalytic fibers of Inventions 8 and 9.

  From the photocatalyst fiber of the present invention, a highly durable porous photocatalyst fiber having excellent performance as an environmental purification material, antifouling material, and easy-cleaning material can be obtained by a simple operation of light irradiation.

Hereinafter, the present invention will be described in detail.
The photocatalytic fiber of the present invention is characterized in that the BET surface area is increased by 0.1 m ² / g or more when irradiated with light. From the photocatalyst fiber of the present invention, a porous photocatalyst fiber excellent in environmental purification function and the like is formed by the light irradiation.
The photocatalyst fiber of the present invention contains a photocatalyst (a), preferably a photocatalyst (a), a photocatalytic affinity organic component (B) that has a strong affinity for the photocatalyst and is decomposed by the photocatalytic action, and easily by the photocatalytic action. Containing a complex compound (BC) bound to a hardly-decomposable component (C) that does not decompose. In such a photocatalyst fiber, the photocatalytic affinity organic component (B) adjacent to the photocatalyst (a) is efficiently and selectively decomposed by light irradiation, and the photocatalyst (a) is present due to the presence of the hardly decomposable component (C). In order to prevent detachment from the fiber, it is induced by a porous photocatalyst fiber having an excellent environmental purification effect and antifouling effect with almost no change in the structure of the external appearance and an increased BET surface area. In addition, the presence of the hardly decomposable component (C) prevents the photocatalytic degradation of the fiber by the photocatalyst (a) and greatly contributes to the development of the excellent durability of the porous photocatalytic fiber of the present invention.

Moreover, in the photocatalyst fiber of the present invention, the composite compound (BC) containing the modified photocatalyst (A) obtained by modifying the photocatalyst (a) has a very large increase in BET surface area due to the light irradiation. It is most preferable because it is excellent in uniformity of pores.
Here, the modification treatment means immobilizing the composite compound (BC) on the surface of the photocatalyst (a). Immobilization of the composite compound (BC) on the surface of the photocatalyst particles is 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 composite compound (BC) and the photocatalyst is strong and the composite compound (BC) is firmly immobilized on the surface of the photocatalyst particles.

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, a short wavelength) is irradiated, excitation (photoexcitation) of electrons in the valence band occurs, resulting in conduction. It is a substance that can generate 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. Can do. For example, oxidative decomposition reaction of various organic substances can be mentioned.
Examples of the photocatalyst (a) include a semiconductor compound having a band gap energy of preferably 1.2 to 5.0 eV, more preferably 1.5 to 4.1 eV. If the band gap energy is less than 1.2 eV, the ability to cause oxidation and reduction reaction by light irradiation is very weak, which is not preferable. If the band gap energy is larger than 5.0 eV, the energy of light necessary for generating holes and electrons becomes very large, which is not preferable.

Examples of the photocatalyst (a) include TiO ₂ , ZnO, SrTiO ₃ , CdS, GaP, InP, GaAs, BaTiO ₃ , 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, and V (for example, JP 62-74452 A, JP 2-172535 A, JP-A-7-24329, JP-A-8-89799, JP-A-8-89800, JP-A-8-89804, JP-A-8-198061 JP-9-248465, JP-A No. 10-99694 and JP-reference Publication No. Hei 10-244165) can be mentioned.
Of these photocatalysts (a), TiO ₂ (titanium oxide) is preferable because it is harmless and has excellent chemical stability. Any of anatase, rutile, and brookite can be used as titanium oxide.

  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 derivatization of the inventive photocatalytic fiber into a porous photocatalytic fiber also occurs with visible light. The produced porous photocatalyst fiber is preferable because it can sufficiently exhibit an environmental purification effect and an antifouling effect even in a place where ultraviolet rays are not sufficiently irradiated, such as indoors. The bandgap energy of these visible light responsive photocatalysts is preferably 1.2 to 3.1 eV, more preferably 1.5 to 2.9 eV, and still more preferably 1.5 to 2.8 eV.

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.
The oxynitride compound that can be particularly preferably used in the present invention is an oxynitride containing a transition metal, and preferably has a high photocatalytic activity, and the transition metal is preferably selected from the group consisting of Ta, Nb, Ti, Zr, and W. The oxynitride is characterized in that it further comprises at least one element selected from the group consisting of alkali, alkaline earth and group IIIB metals. The oxynitride further includes at least one metal element selected from the group consisting of Ca, Sr, Ba, Rb, La, and Nd.

Examples of oxynitride containing the transition _{metal, LaTiO 2 N, La v Ca} w TiO 2 N (v + w = 3), La v Ca w TaO 2 N (v + w = 3), LaTaON 2, CaTaO 2 N, General formula AMO _x N _y such as SrTaO ₂ N, BaTaO ₂ N, CaNbO ₂ N, CaWO ₂ N, SrWO ₂ N (A = alkali metal, alkaline earth metal, group IIIB metal; M = Ta, Nb, Ti, Zr, W; x + y = 3), TaON, NbON, WON, Li ₂ LaTa ₂ O ₆ N and the like. Among these, LaTiO ₂ N, La _v Ca _w TiO ₂ N (v + w = 3), La _v Ca _w TaO ₂ N (v + w = 3), and TaON are preferable because the photocatalytic activity in visible light is very large.

The oxysulfide compound that can be used particularly preferably in the present invention is an oxysulfide containing a transition metal, and has a high photocatalytic activity, and the transition metal is preferably selected from the group consisting of Ta, Nb, Ti, Zr, and W. Oxysulfide, characterized in that it is at least one, more preferably at least one element selected from the group consisting of alkali, alkaline earth and group IIIB metals More preferably, the oxysulfide is characterized by further containing a rare earth element.
Examples of the oxysulfide containing the transition metal include Sm ₂ Ti ₂ S ₂ O ₅ , Nd ₂ Ti ₂ S ₂ O ₅ , La ₆ Ti ₂ S ₈ O ₅ , Pr ₂ Ti ₂ S ₂ O ₅ , and Sm _3. NbS ₃ O _{4 and the} like can be mentioned. Among these, Sm ₂ Ti ₂ S ₂ O ₅ and Nd ₂ Ti ₂ S ₂ O ₅ are very preferable because of their very high photocatalytic activity under visible light.

Further, as a photocatalyst (a) in the present invention, a metal-modified apatite obtained by ion-exchange of a part of metal ions in an apatite crystal with a metal ion of a metal oxide having a photocatalytic action (for example, titanium ion) 2000-327315 public information) can also be suitably used because of its excellent adsorption characteristics against bacteria, viruses, dirt and the like.
Furthermore, the above-mentioned photocatalyst (a) is preferably added or fixed with a metal such as Pt, Rh, Ru, Nb, Cu, Sn, Ni, Fe and / or an oxide thereof, or coated with porous calcium phosphate or the like. It can also be used as a photocatalyst (see, for example, 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.
In the present invention, the composite compound (BC) is, for example, a hardly decomposable component (C) having a photocatalytic affinity organic component (B) as a functional group, or a graft of a photocatalytic affinity organic component (B) and a hardly decomposable component (C). A polymer, a block polymer, a random polymer, etc. can be illustrated.
Examples of the photocatalytic affinity organic component (B) in the present invention include, for example, a hydroxyl group present on the surface of the photocatalyst particles and a polyoxyalkylene group having affinity with physically adsorbed water, polyvinyl alcohol, modified polyvinyl alcohol, partially saponified polyvinyl acetate, and acrylic. Acid polymer (including copolymer), methacrylic acid polymer (including copolymer), acrylamide polymer (including copolymer), styrene sulfonic acid polymer (including copolymer), vinylpyrrolidone heavy Examples thereof include a combination (including a copolymer), polyallylamine, carboxymethylated cellulose, and carboxymethylated nitrocellulose.

Of these, polyoxyalkylene groups are preferred because they are generally excellent in affinity for photocatalysts and can be easily decomposed by photocatalytic action.
In the present invention, the hardly decomposable component (C) preferably has a mass reduction of 5% or less when irradiated with black light for 5 hours so that the ultraviolet intensity of the photocatalyst fiber surface is 7 mW / cm ^2. Etc. can be mentioned.
Specific examples of the hardly decomposable component (C) include inorganic compounds such as water glass, silicone resins, and fluorine resins.

  In the present invention, examples of the silicone resin include dimethylpolysiloxane, methylphenylpolysiloxane, methylhydrogenpolysiloxane, alkoxy group-containing silicone oil, silanol group-containing silicone oil, vinyl group-containing silicone oil, octamethylcyclotetra Silicone oils such as siloxane and decamethylcyclopentasiloxane, alcohol-modified silicone, alkyl-modified silicone, modified silicones such as fluoroalkyl-modified silicone, (alkyl) alkoxy such as tetraethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane Silane monomers, oligomers and polymers, vinyltrichlorosilane, vinyltrimethoxysilane, γ-aminopropyltrimethoxysilane, etc. Silane coupling agents and reaction products thereof, silicone surfactants or the like. These silicones can be used alone or in combination of two or more.

  In the present invention, examples of the fluororesin include 2-perfluorooctylethyltrimethoxysilane, 2-perfluorooctylethyltriethoxysilane, 2-perfluorooctylethylmethyldimethoxysilane, trifluoromethylethyltrimethoxysilane, Fluoroalkylsilanes such as trifluoromethylethyltriethoxysilane and their polycondensates, PTFE and polyvinylidene fluoride, and also fluoroolefins and monomers such as Nafion resin, chlorotrifluoroethylene and tetrafluoroethylene (vinyl ether, vinyl) And copolymers with esters and allyl compounds). These fluororesins can be used alone or in combination of two or more.

In the present invention, preferred examples of the composite compound (BC) include a Si compound represented by the following formula (1) and a fluorine-based resin having a polyoxyalkylene group.
_{R x X y Q z SiO (} 4-x-y-z) / 2 (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 number having 1 to 30 carbon atoms. It represents a group consisting of one or more selected from a fluoroalkyl group, a linear or branched alkenyl group having 2 to 30 carbon atoms, and a phenyl group.)

Q represents a group containing a polyoxyalkylene group represented by the following formula (2).
— (O) _a R ¹ O (R ² O) _b R ³ (2)
(Wherein R ¹ and R ² each independently represents a linear or branched alkylene group having 1 to 10 carbon atoms. R ³ represents a hydrogen atom, a linear or branched carbon group having 1 to 30 carbon atoms. An alkyl group, a cycloalkyl group having 5 to 20 carbon atoms, or a linear or branched alkenyl group having 2 to 30 carbon atoms and a phenyl group, a is 0 or 1, and b is an integer of 1 to 100 Represents.)

X represents each 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, an oxime group having 1 to 20 carbon atoms, or a halogen atom. Further, 0 ≦ x <4, 0 ≦ y <4, 0 <z <4, and 0 <(x + y + z) <4. )
In the photocatalyst fiber of the present invention, a system containing the above-described photocatalyst (a) and composite compound (BC) in a mass ratio (A) / (BC) = 0.001 to 1000 is preferable.

In the present invention, the composite compound (BC) useful for modifying the photocatalyst (a) includes, for example, a Si—H group, a hydrolyzable silyl group (alkoxysilyl group, hydroxysilyl group, halogenated silyl group, acetoxy group). Suitable examples include those having reactivity with the photocatalyst particles (a) such as silyl group, aminoxysilyl group, etc.), epoxy group, acetoacetyl group, thiol group, acid anhydride group and the like.
In the present invention, the modification treatment of the photocatalyst (a) with the composite compound (BC) is preferably performed by mass ratio of the photocatalyst (a) and the composite compound (BC) in the presence or absence of water and / or an organic solvent. (A) / (BC) = 1/99 to 99.9 / 0.1, more preferably (a) / (BC) = 10/90 to 99/1, preferably at 0 to 200 ° C. Can be implemented.
In the present invention, when a compound containing a Si—H group is used as the composite compound (BC) used for modification of the photocatalyst (a), the particle surface of the photocatalyst (a) can be modified very efficiently. preferable.

As a preferable example of the composite compound (BC) having the Si—H group, for example, a Si—H group-containing compound (b1) represented by the formula (3) and / or the formula (4) can be exemplified.
_{H- (R 2 SiO) m -SiR} 2 -Q (3)
(In the formula, R and Q are as defined in formula (1). M is an integer, and 0 ≦ m ≦ 1000.)
(RHSiO) _p (R ₂ SiO) _q (RQSiO) _r (R ₃ SiO _1/2 ) _s (4)
(Wherein R and Q are as defined in formula (1)).
p is an integer of 1 or more, q and r are 0 or an integer of 1 or more, (p + q + r) ≦ 10000, and s is 0 or 2. However, when (p + q + r) is an integer of 2 or more and s = 0, the H silicone compound is a cyclic silicone compound, and when s = 2, the H silicone compound is a chain silicone compound. )

In the present invention, the modification treatment of the photocatalyst (a) with the Si—H group-containing compound (b1) represented by the formula (3) and / or the formula (4) is performed in the presence or absence of water and / or an organic solvent. Below, the photocatalyst (a) and the Si—H group-containing compound (b1) are preferably mass ratio (a) / (b1) = 1/99 to 99.9 / 0.1, more preferably (a) / (B1) = A ratio of 10/90 to 99/1, preferably by mixing at 0 to 200 ° C.
In the case of modification using chemical bonds by this modification operation, for example, hydrogen gas is generated from the mixed solution, and when the photocatalyst sol is used as the photocatalyst (a), an increase in the average particle diameter is observed. The
In addition, when titanium oxide is used as the photocatalyst (a) and modification is performed using a chemical bond, for example, by the above-described modification operation, the decrease in Ti—OH groups decreases or disappears at 3630 to 3640 cm ^{−1 in} the IR spectrum. As observed.

Accordingly, the modified photocatalyst (A) modified with the Si—H group-containing compound (b1) represented by the formula (3) and / or the formula (4) is the Si—H group-containing compound (b1). It can be predicted that some kind of interaction is caused between the two and the photocatalyst (a) due to a chemical reaction.
In fact, the modified photocatalyst (A) thus obtained is very excellent in dispersion stability, transparency, chemical stability, durability and the like with respect to the solvent.

  The photocatalyst fiber of the present invention contains a sensitizing dye, even if the photocatalyst (a) responds only to ultraviolet rays such as titanium oxide, an increase in BET surface area due to light irradiation of the photocatalyst fiber described later ( The generation of porous photocatalyst fibers) is caused by light in the visible light region, and the generated porous photocatalyst fibers can exhibit environmental purification effects and antifouling effects even in places such as indoors where ultraviolet rays are not sufficiently irradiated. Therefore, it is preferable.

The sensitizing dye that can be used in the present invention refers to various metal complexes and organic dyes having absorption in the visible light region. Examples of such sensitizing dyes include xanthene dyes, oxonol dyes, cyanine dyes, merocyanine dyes, rhodocyanine dyes, styryl dyes, hemicyanine dyes, merocyanine dyes, phthalocyanine dyes (metal complexes). ), Porphyrin dyes (including metal complexes), triphenylmethane dyes, perylene dyes, coronene dyes, azo dyes, nitrophenol dyes, and JP-A 1-220380 and patent application publications Examples thereof include a complex of ruthenium, osmium, iron, and zinc described in JP-A-5-504023 and a metal complex such as ruthenium red.
Among these sensitizing dyes, those having absorption in a wavelength region of 400 nm or more and having the lowest empty orbital energy level (excited state redox potential) higher than the energy level of the photocatalytic conduction band are preferably selected. Is done. Such sensitizing dyes can be selected by measuring light absorption spectra in the infrared, visible and ultraviolet regions, measuring redox potentials by electrochemical methods, calculating energy levels using molecular orbital methods, and It can be carried out depending on the presence / absence of electromotive force or the efficiency of the light irradiation of a Gratzel-type wet solar cell prepared with a photocatalyst and a spectral sensitizing dye.

Examples of preferred sensitizing dyes from such a viewpoint include compounds having a 9-phenylxanthene skeleton (such as fluorescein, eosin Y, eosin B, rose bengal, rhodamine B, phloxine, pyrogallol, uranin, acid red, etc.) Examples thereof include a ruthenium complex containing a 2,2-bipyridine derivative as a ligand, ruthenium red, a compound having a perylene skeleton, a phthalocyanine metal complex, and a porphyrin metal complex.
In the photocatalyst fiber of the present invention, when a material containing an adsorptive deodorant is selected, the deodorizing effect of the porous photocatalyst fiber obtained by light irradiation is imparted with a rapid effect, and the deodorizing function can be expressed more efficiently. preferable.

  The adsorptive deodorant used in the present invention refers to, for example, a physical adsorbent, a chemical adsorbent, a physicochemical adsorbent, etc., which adsorbs malodorous substances and exerts a deodorizing effect, and is colorless or white. Non-toxic materials are preferred. Examples of such adsorptive deodorants include zeolite (hydrophilic and hydrophobic), activated clay, acidic clay, hydrotalcite, sepiolite, silica-alumina, silica-magnesia, composition of silica and zinc oxide, activated carbon, and the like. Examples of physical adsorbents include Absenz (trade name, manufactured by Union Showa Co., Ltd.), and examples of chemical adsorbents include Schueklens (trade name, manufactured by Rasa Industrial Co., Ltd.) and Kyoward (manufactured by Kyowa Chemical Industry Co., Ltd.). Etc.) are commercially available. These can be used alone or in combination of two or more.

Further, in the photocatalyst fiber of the present invention, an adsorption-type deodorant-photocatalyst composite modified photocatalyst (A ′) modified with the above-mentioned composite compound (BC) in the coexistence of the photocatalyst (a) and the adsorption-type deodorant. ) Is very preferable because the above-described synergistic effect of the adsorption deodorant and the photocatalyst can be efficiently expressed.
In the photocatalyst fiber of the present invention, when an antibacterial metal-containing fiber is selected, the antibacterial / antifungal effect of the porous photocatalyst fiber obtained by light irradiation is quickly given, and the antibacterial / antifungal function is more efficient. It is preferable because it can be expressed dynamically. In other words, antibacterial metals are known to have antibacterial and strong antibacterial and antifungal effects due to photocatalysis when exposed to light. Can be combined with antibacterial and antifungal effects of antibacterial metals in the dark.

Examples of the antibacterial metal that can be used in the present invention include metals such as silver, copper, platinum, gold, palladium, nickel, cobalt, rhodium, niobium, tin, and / or oxides thereof and mixtures thereof. Can do. Among these, it is preferable to use silver or copper.
The antibacterial metal can be used by simply adding to or immobilizing the photocatalyst (a) (preferably the modified photocatalyst (A)). Examples of the method for immobilizing the antibacterial metal on the photocatalyst (a) (preferably the modified photocatalyst (A)) include a method of physically adsorbing the antibacterial metal, a method of immobilization by a photoreduction method or heat treatment. Alternatively, the antibacterial metal can be immobilized on the photocatalyst (a) by physical adsorption, photoreduction, heat treatment or the like, and then modified by the above-described method using the composite compound (BC).

The photocatalyst fiber of the present invention contains a resin (F) with respect to the photocatalyst (a) of the present invention for the purpose of assisting the adhesion of the photocatalyst (a) (preferably the modified photocatalyst (A)) to the fiber. The mass ratio (a) / (F) = 1/99 to 99/1, preferably (a) / (F) = 10/90 to 90/10 can also be used.
As the resin (F) that can be used for the photocatalytic fiber of the present invention, all synthetic resins and natural resins can be used.

As the synthetic resin, thermoplastic resin and curable resin (thermosetting resin, photocurable resin, moisture curable resin, etc.) can be used. For example, 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, silicone resin, water glass and zirconi Beam compounds include 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 addition, the photocatalyst fiber of the present invention contains a pigment, a crosslinking agent, a filler, a dispersing agent, a light stabilizer, a wetting agent, a plasticizer, a dye, an antiseptic, and the like, if necessary, in combination. be able to.

The photocatalyst fiber of the present invention includes, for example, the above-described components that can be contained in a photocatalyst fiber such as a photocatalyst (a) and a composite compound (BC) (preferably a modified photocatalyst (A)) or a sensitizing dye, if necessary. And by treating the fiber with a photocatalyst composition (D) containing a solvent and the like.
Examples of the solvent that can be suitably used for the photocatalyst composition (D) include water, alcohols such as ethylene glycol, butyl cellosolve, n-propanol, isopropanol, n-butanol, ethanol, and methanol, and aromatics 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, Examples include amides such as dimethylacetamide and dimethylformamide, halogen compounds such as chloroform, methylene chloride, and carbon tetrachloride, dimethyl sulfoxide, nitrobenzene, and a mixture of two or more of these.

In the present invention, the fiber is treated with the photocatalyst composition (D), for example, after the photocatalyst composition (D) is coated or impregnated on the fiber and dried, it is preferably 20 ° C. to 500 ° C., more preferably 40 ° C. as desired. It can be carried out by performing a heat treatment at a temperature of from 250C to 250C, ultraviolet irradiation or the like. Examples of the coating method include, for example, a method in which spinning is performed or after spinning, and if necessary, a processed body is immersed in a reservoir, spray spraying method, flow coating method, roll coating method, brush coating method, dip coating method , Padding method, spin coating method, casting method, sponge coating method and the like.
At this time, the content of the photocatalyst (a) in the photocatalyst fiber of the present invention is preferably 0.001 to 50% by mass, more preferably 0.1 to 30% by mass with respect to the fiber mass. When the content of the photocatalyst (a) is less than 0.001% by mass, the photocatalytic activity of the photocatalyst fiber is low, and when it exceeds 50% by mass, the yarn forming property and the yarn physical properties are deteriorated.

In addition, when the photocatalyst fiber processed body is paper in the present invention, the photocatalyst composition (D) may be used in the papermaking process in addition to treating the paper with the photocatalyst composition (D) by the coating or impregnation method. Is possible. At this time, if necessary, the photocatalyst composition (D) can contain a dispersion stabilizer such as a cationic dispersant, an anionic dispersant, or a nonionic dispersant.
Examples of fibers that can be preferably used in the present invention include at least one selected from synthetic fibers, natural fibers, recycled fibers, metal fibers, and ceramic fibers. Preferable specific examples of the fibers include polyester fibers, polyamide fibers, polyacrylic fibers, polyvinyl fibers, polypropylene fibers, polyethylene fibers, polyurethane fibers, and other elastic fibers (typically magnesium oxide and zinc oxide). Synthetic fibers such as metal oxides, and those added with chlorine water deterioration inhibitors such as metal hydroxides), natural fibers such as cotton, hemp, wool and silk, and celluloses such as cupra, rayon and polynosic Examples thereof include fibers and acetate fibers.

  Moreover, if the single yarn fineness of a fiber is 100 dtex or less, it is preferable because there is a sufficient surface area as a fiber. Moreover, if the single yarn fineness is 0.1 dtex or more, a practical mechanical strength as a fiber can be secured even if the photocatalyst (a) is contained. The single yarn fineness is more preferably 1 to 50 dtex. Further, the cross-sectional shape of the fiber can be freely selected for a round cross-section, a hollow cross-section, a multi-leaf cross-section such as a trilobal cross-section, and other irregular cross-sections. In addition, in particular, synthetic fibers are not limited to single polymer fibers, but of course, polymer blend fibers with other polymers, and composite fibers such as core-sheath composites. The form of the synthetic fiber is not particularly limited, such as long fiber and short fiber.

In another aspect of the present invention, a processed body comprising a photocatalytic fiber is provided. The processed body is not only various fabrics such as woven fabrics, knitted fabrics and non-woven fabrics (short fibers or long fibers), paper, and fiber molded bodies, but also products including photocatalytic fibers such as strips, strings, and threads. It can be used regardless of its structure and shape.
The photocatalyst fiber processed body is formed by processing a photocatalyst fiber (in combination with a fiber not containing a photocatalyst (a) if necessary) into various structures, or processing a fiber processed body having various structures with the photocatalyst composition (D), for example. It can be obtained by processing by the method described above.

The photocatalyst fiber of the present invention is irradiated with light having energy higher than the band gap energy of the photocatalyst (a) contained (in the case of containing a sensitizing dye, light including light absorbed by the sensitizing dye). The surface area is preferably increased by 0.1 m ² / g or more, more preferably 1 m ² / g or more, and even more preferably 10 m ² / g or more. The porous photocatalyst fiber suitably obtained in this manner is extremely excellent in environmental purification functions (toxic organic matter decomposition, antibacterial performance, antifungal performance, etc.) and antifouling functions (contaminated organic matter decomposition, etc.). These functions become significant when the increase in BET surface area is 1 m ² / g or more, and becomes remarkable when the increase is 10 m ² / g or more. In addition, from the photocatalyst fiber processed body including the photocatalyst fiber, a porous photocatalyst fiber processed body having an environmental purification function such as antifouling performance and dirt decomposition performance can be obtained by the light irradiation.

The increase in the BET surface area of the photocatalyst fiber by the above-mentioned light irradiation can be controlled by the content of the photocatalyst (a) of the photocatalyst fiber, but the increase in the BET surface area per 1 g of the photocatalyst (a) contained is preferably 10 m ^2. As described above, more preferably, the porous photocatalyst fiber obtained when it is 50 m ² or more can exhibit an excellent environmental purification function and antifouling function.
Here, when the photocatalyst (a) is contained in the fiber as the modified photocatalyst (A), the mass of the photocatalyst (a) refers to the mass obtained by removing the composite compound (BC) from the modified photocatalyst (A).
The porous photocatalyst fiber and its processed body, which has a high hydrophilicity with a moisture absorption rate of 5 to 30%, has a very strong affinity for water, and therefore easily removes sebum stains by washing or washing with water. This is preferable.

Further, the photocatalyst fiber of the present invention or the porous photocatalyst fiber derived therefrom, wherein the photocatalyst (a) has a fiber surface of preferably 50% or more, more preferably 80% or more, and still more preferably 100% coating is very preferable because the photocatalyst (a) itself can prevent deterioration and yellowing of the fiber due to ultraviolet rays due to the ultraviolet absorbing ability. The fiber coverage by the photocatalyst (a) can be estimated by SEM observation of the photocatalyst fiber and the porous photocatalyst fiber derived therefrom.
Furthermore, a processed body made of a photocatalyst fiber or a porous photocatalyst fiber having a large fiber coverage of the photocatalyst (a) is very preferable because deterioration and yellowing due to ultraviolet rays are very little. In addition, a processed body made of a photocatalyst fiber or a porous photocatalyst fiber having a high fiber coverage of the photocatalyst (a) is preferable because it has an excellent ultraviolet-absorbing function and thus has an excellent ultraviolet shielding function.

In the photocatalyst fiber having a large coverage with respect to the fiber of the photocatalyst (a), when the photocatalyst (a) is in direct contact with the fiber, the fiber itself is efficiently decomposed by the photocatalytic action. When the modified photocatalyst (A) is contained in the fiber, it is very preferable because the photocatalytic degradation of the fiber itself can be prevented by the protective effect of the fiber by the hardly decomposable component (C) of the composite compound (BC).
In the present invention, as a light source of light containing energy higher than the band gap energy of the photocatalyst (a) or light absorbed by the sensitizing dye, for example, light sources in the environment such as sunlight, street lamps, nightlights, and more Lighting is available. As general illumination, fluorescent lamps, incandescent lamps, metal halide lamps, black light lamps, xenon lamps, mercury lamps, LEDs, and the like can be suitably used. Illuminance of the light is preferably in 0.001 mW / cm ² or more, more preferably when it 0.01 mW / cm ² or more, further preferably it 0.1 mW / cm ² or more.

Further, in another aspect of the present invention, various members to which the photocatalyst fiber of the present invention or a processed product thereof is attached are provided by providing a pressure-sensitive adhesive layer or using a transparent adhesive.
For the purpose of antibacterial, antifouling, deodorizing, and toxic gas decomposition, the photocatalyst fiber of the present invention and its processed body are, for example, in the form of a fabric, a woven fabric, a knitted fabric, a non-woven fabric, a garment, a filter (especially for gas and liquid), a building, It can be used for interior materials, fixtures, accessories, etc. of vehicles.

  As a more specific application example of the photocatalyst fiber and the processed body of the present invention, for example, clothing (including outer and inner), especially sports, medical care, and nursing care can be mentioned. A three-dimensional knitted fabric is particularly preferable because of good fit. The filter (especially for gas and liquid) may be processed into a form that can be attached to the human body, such as a hollow fiber or sheet processed into a case or a mask. For building interiors, those used directly on buildings, such as wallpaper and shoji paper, as well as those attached to furniture are included. It is also preferable to use it for factories, sports, and medical facilities as well as ordinary households. In this form, those having the above-mentioned pressure-sensitive adhesive attached are easy to use and preferable. It is also useful for lighting fixtures and lighting covers. It is also useful for interiors and fixtures of vehicles, such as automobile seats and other interiors. In particular, the three-dimensional knitted fabric, when used as a cushion material for automobile seats, safety and comfort based on the fit to the human body, exhaust gas and cigarettes generated in the room, body odor, odor decomposition removal of used members, It has both pollution prevention and is useful.

The following examples, reference examples and comparative examples will specifically explain the present invention, 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 an appropriate solvent so that the photocatalyst content in the sample was 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 chromatography column: using connected _TSKgel G1000H _XL, TSKgelG2000H XL and TSKgel G4000H _XL (both manufactured by Tosoh Corp.) were connected serially.
-Data processing device: CR-4A type data processing device manufactured by Shimadzu Corporation-Mobile phase:
Tetrahydrofuran (used for analysis of phenyl group-containing silicone)
Chloroform (used for analysis of 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 adjusted suitably in the range of 0.5-2 weight%), and used for the analysis.

3. Infrared absorption spectrum The infrared absorption spectrum was measured using an FT / IR-5300 type infrared spectrometer manufactured by JASCO Corporation.
4). BET surface area It measured using the nitrogen adsorption apparatus (autosorb-1-MP) made from Yuasa Ionics.
5. Moisture absorption rate Moisture absorption rate was determined by the following formula.
Moisture absorption (%) = ([official weight] ÷ [absolute weight] −1) × 100
Here, the absolutely dry mass is a mass when the sample is dried at 105 ° C. for 2 hours. The official mass is the mass after leaving the sample after absolute dry mass measurement at 20 ° C. in a 65% humidity RH atmosphere for 24 hours.

6). Deodorizing property A sample of 10 cm × 10 cm was put in a 5 l Tedlar bag, and after introducing 3 l of air containing 100 ppm acetaldehyde, the Tedlar bag was sealed. Next, the sample in the Tedlar bag was irradiated with light of a FL20SBLB type black light manufactured by Toshiba Lighting & Technology for 2 hours, and then the amount of acetaldehyde in the Tedlar bag was measured with a gas-tech detector tube.
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 ^2. It adjusted so that it might become.

7). Antifungal test A potato dextrose agar medium previously sterilized was placed in a petri dish and solidified. A test piece (5 cm × 1 cm) was placed on the agar medium. Subsequently, 5 platinum Aspergillus niger (IFO 4414) separately cultured in 10 ml of a 0.005% by mass dioctyl sodium sulfosuccinate aqueous solution was collected, and spores were separated by centrifugation. The fungus with 10 ml of GPLP medium is sprayed onto a petri dish test piece, irradiated with a fluorescent lamp (100 W) at room temperature for 14 days, and then antifungal based on the appearance (visual evaluation) of the sample. Evaluation was made in the following three stages.
○: No growth of mycelia △: Some growth of mycelia is observed ×: Mycelium covers 50-100% of the surface

8). Antibacterial test Put a 5cm x 1cm sample into a sterilized plastic dish, and add the bacterial solution adjusted so that the number of E. coli to about 10 ⁵ cells / ml to each sample in each dish. 0.5 ml each was dropped, and the dish was covered with a polyethylene film to block it from the outside air, thereby preventing the bacterial solution on the specimen sample from drying and the entry of bacteria from the outside. Subsequently, after irradiating the light of the FL20SBLB type black light made by Toshiba Lighting & Technology from outside the petri dish for 4 hours, the bacterial solution was washed from the sample of the petri dish, transferred to the medium, and the number of viable bacteria was measured. Based on the calculated kill rate, antibacterial properties were evaluated in the following three stages.
Death rate = {(initial viable cell count−viable cell count after test) / initial viable cell count} × 100
○: Death rate 80% or more △: Death rate 20% or more and less than 80% ×: Death rate 20% or less UV intensity is a UVR-2 type UV intensity meter made by Topcon {as a light receiving part, a UD-36 type light receiving part made by Topcon (Corresponding to light having a wavelength of 310 to 400 nm) was used to adjust the ultraviolet intensity measured to 1 mW / cm ² .

9. 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 3 mW / cm ^2. It adjusted so that it might become.
○: No change in appearance △: Yellowing ×: Partial decomposition of members

10. Easy washability Samples were 40.6% by weight oleic acid, 22.4% by weight triolein, 17.5% by weight cholesterol oleate, 3.6% by weight liquid paraffin, 2.3% by weight cholesterol and 10.0% by weight gelatin. After being soaked in 30 g / l of artificial sweat containing as a main component, it was squeezed at a squeezing rate of 130%, dried at 105 ° C. for 30 minutes, washed in ordinary household, and then dried in the sun. .
After repeating the above immersion, squeezing, drying, washing, and sun drying operations 5 times, the degree of dirt removal was evaluated based on the appearance (visual evaluation) of the sample in the following three stages. .
○: No change in appearance △: Slight yellowing ×: Severe yellowing

11. SEM observation of fiber The conditions for SEM observation are as follows.
・ Device: JSM-5600LV type manufactured by JEOL ・ Acceleration voltage: 20kV
The location of photocatalytic titanium oxide was analyzed by EDX analysis of Ti element.

[Reference Example 1]
Synthesis of modified photocatalytic hydrosol (A-1).
LS-8600 [trade name of 1,3,5,7-tetramethylcyclotetrasiloxane (manufactured by Shin-Etsu Chemical Co., Ltd.)] 474 g, LS-8620 [Octamethyl] Trade name of cyclotetrasiloxane (manufactured by Shin-Etsu Chemical Co., Ltd.)] 76.4 g, product name of LS-8490 [1,3,5-trimethyl-1,3,5-triphenylcyclotrisiloxane (manufactured by Shin-Etsu Chemical Co., Ltd.) 408 g LS-7130 [trade name of hexamethyldisiloxane (manufactured by Shin-Etsu Chemical Co., Ltd.), 40.5 g, and sulfated zirconia 20 g were charged, stirred at 50 ° C. for 3 hours, and further stirred at 80 ° C. for 5 hours. . After filtering the sulfated zirconia, the low-boiling components were removed under vacuum at 130 ° C., and a methylhydrogensiloxane-methylphenylsiloxane-dimethylsiloxane copolymer (weight average molecular weight 6600, Si—H group content 7.93 mmol / g) ( 780 g of a synthetic silicone compound) was obtained.

Into a reactor equipped with a reflux condenser, a thermometer and a stirrer, 40 g of the synthetic silicone compound was put, and the temperature was raised to 80 ° C. with stirring. To this, UNIOX PKA-5118 [trade name of polyoxyethylene allyl methyl ether (manufactured by NOF Corporation), weight average molecular weight 800] 200 g, dehydrated methyl ethyl ketone 200 g, and chloroplatinic acid hexahydrate 5 mass% isopropanol solution 1 0.0 g of the mixed solution was added over about 1 hour with stirring, and the mixture was further stirred at 80 ° C. for 5 hours and then cooled to room temperature to obtain a Si—H group-containing compound solution (1). It was.
When 100 g of water was added to 4 g of the obtained Si—H group-containing compound solution (1), a transparent aqueous solution was obtained.
Further, 8 g of butyl cellosolve was added to and mixed with 3.97 g of the obtained Si—H group-containing compound solution (1), and then 8 ml of 1N sodium hydroxide aqueous solution was added to generate hydrogen gas. 21.0 ml. The Si—H group content per 1 g of the Si—H group-containing compound solution (1) determined from this hydrogen gas production amount was 0.22 mmol / g (the Si—H group content calculated per 1 g of the synthetic silicone compound was about 2 .37 mmol / g).

To a reactor equipped with a reflux condenser, a thermometer and a stirrer, TKS-203 [trade name of titanium oxide hydrosol (manufactured by Teika), neutral, TiO2 concentration 19.2 mass%, average crystallite diameter 6 nm (catalog Value)] After adding 78.1 g and 221.9 g of water, 41.3 g of the synthesized Si—H group-containing compound solution (1) was added thereto at 40 ° C. with stirring over about 30 minutes, After further stirring for 12 hours at 40 ° C., methyl ethyl ketone was removed by distillation under reduced pressure, and water was added to obtain 5% by mass of a highly-dispersible modified photocatalyst hydrosol (A-1). At this time, the amount of hydrogen gas produced by the reaction of the Si—H group-containing compound solution (1) was 210 ml at 20 ° C. Further, when the obtained modified titanium oxide hydrosol (A-1) was coated on a KBr plate and the IR spectrum was measured, the disappearance of absorption of Ti—OH groups (3630 to 3640 cm ⁻¹ ) was observed.

Moreover, the particle size distribution of the obtained modified photocatalyst hydrosol (A-1) is a single dispersion (number average particle diameter is 55 nm), and further, the single dispersion of TKS203 before the modification treatment (number average particle diameter is 12 nm). It was confirmed that the particle size distribution of the particles moved parallel to the larger particle size side.
The obtained modified photocatalyst hydrosol (A-1) was applied to a glass plate with a thickness of about 1 μm and dried at room temperature, and the BET surface area was less than 0.1 m ² / g. In contrast, after applying the modified photocatalyst hydrosol (A-1) to a glass plate with a thickness of about 1 μm and drying at room temperature, the light of FL20S BLB type black light manufactured by Toshiba Lighting & Technology [UVR-2 type UV intensity manufactured by Topcon] Irradiated with a meter {adjusted so that the UV intensity measured 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 ] for 5 days Increased the BET surface area to 210 m ² / g.

[Reference Example 2]
Synthesis of modified photocatalytic hydrosol (A-2).
A reactor equipped with a reflux condenser, a thermometer, and a stirrer was charged with 15 g of TSS4110 [trade name of visible light responsive titanium oxide sol (manufactured by Sumitomo Chemical Co., Ltd., photocatalyst concentration 10 mass%)] and 15 g of water. 4.1 g of the Si—H group-containing compound solution (1) synthesized in Reference Example 1 was added at 40 ° C. over about 30 minutes with stirring, and stirring was continued at 40 ° C. for 12 hours, followed by vacuum distillation. Then, methyl ethyl ketone was removed and water was added to obtain a modified photocatalyst hydrosol (A-2) having a very good dispersibility of 5% by mass. At this time, the amount of hydrogen gas produced by the reaction of the Si—H group-containing compound solution (1) was 25 ml at 20 ° C.
Moreover, the particle size distribution of the obtained modified photocatalyst hydrosol (A-2) is monodisperse (number average particle size is 29 nm), and further monodispersion of TSS4110 before modification (number average particle size is 13 nm). It was confirmed that the particle size distribution of the particles moved parallel to the larger particle size side.

[Example 1]
The modified photocatalyst hydrosol (A-1) obtained in Reference Example 1 was dipped in 10 cm × 10 cm Japanese paper having a BET surface area of 1.8 m ² / g and then dried at room temperature for 12 hours to have a photocatalyst content of about 10 mass. % Photocatalytic Japanese paper 1 (photocatalyst fiber processed body 1) was prepared. The obtained photocatalytic Japanese paper 1 had a BET surface area of 2.5 m ² / g.
The resulting photocatalytic Japanese paper 1 is light of FL20SBLB type black light manufactured by Toshiba Lighting & Technology [UVR-2 type UV intensity meter manufactured by Topcon (light receiving unit: UD-36 type light receiving unit manufactured by Topcon), and the UV intensity measured is 2 mW / cm. ² ] was irradiated for 24 hours to obtain a porous photocatalyst Japanese paper 1 having a BET surface area of 22.5 m ² / g. At this time, the increase in the BET surface area per 1 g of the photocatalyst contained in the photocatalyst Japanese paper 1 can be calculated as about 200 m ² .

As a result of SEM observation of the photocatalytic Japanese paper 1 and the porous photocatalytic Japanese paper 1, it was observed that the photocatalytic titanium oxide covered the entire surface of the fiber in both Japanese papers.
When the deodorizing property of this porous photocatalytic Japanese paper 1 was evaluated, 100 ppm of acetaldehyde became 0 ppm (below the detection limit) after irradiation with black light. In addition, the antifungal property of this porous photocatalytic Japanese paper 1 was good (◯), and the antibacterial property was also good (◯). Moreover, the light resistance of the porous photocatalyst Japanese paper 1 was good (◯).
Furthermore, when the deodorizing property was evaluated again using the porous photocatalyst Japanese paper 1 after the light resistance test, 100 ppm of acetaldehyde was 0 ppm (below the detection limit) after irradiation with black light, and the deodorizing performance was maintained.

[Example 2]
In place of the modified photocatalyst hydrosol (A-1) obtained in Reference Example 1, the same procedure as in Example 1 was carried out except that the modified photocatalyst hydrosol (A-2) obtained in Reference Example 2 was used. About 10 mass% of photocatalyst Japanese paper 2 (photocatalyst fiber processed body 2) was prepared. The resulting photocatalytic Japanese paper 2 had a BET surface area of 2.3 m ² / g.
The resulting photocatalyst Japanese paper 2 is light of a fluorescent lamp (Mellow 5N) manufactured by Toshiba Lighting & Technology [Topcon UVR-2 type UV intensity meter {as the light receiving unit, UD-40 type light receiving unit (wavelength of 370 to 490 nm) ) Is used to adjust the visible light intensity to 0.5 mW / cm ² . At this time, the UV intensity measured with a Topcon UD-36 type light receiving unit (corresponding to light having a wavelength of 310 to 400 nm) is 15 μW / cm ² ] for 5 days, so that a BET surface area of 12.5 m ² / g is obtained. Photocatalytic Japanese paper 2 was obtained. At this time, the increase in the BET surface area per 1 g of the photocatalyst contained in the photocatalyst Japanese paper 2 can be calculated as about 100 m ² .

As a result of SEM observation of the photocatalytic Japanese paper 2 and the porous photocatalytic Japanese paper 2, it was observed that the photocatalytic titanium oxide covered the entire surface of the fibers in both Japanese papers.
When the deodorizing property of this porous photocatalyst Japanese paper 2 was evaluated, 100 ppm of acetaldehyde became 5 ppm after irradiation with black light. In addition, the antifungal property of this porous photocatalytic Japanese paper 1 was good (◯), and the antibacterial property was also good (◯). Moreover, the light resistance of the porous photocatalyst Japanese paper 2 was good (◯).
Furthermore, when the deodorizing property was evaluated again using the porous photocatalyst Japanese paper 2 after the light resistance test, 100 ppm of acetaldehyde was 0 ppm (below the detection limit) after irradiation with black light, and the deodorizing performance was maintained.

[Example 3]
0.01 g of eosin Y was added as a sensitizing dye to 100 g of the modified photocatalyst hydrosol (A-1) obtained in Reference Example 1, and the same operation as in Example 1 was carried out to prepare a photocatalyst Japanese paper 3 having a photocatalyst content of about 10% by mass. (Photocatalyst fiber processed body 3) was prepared. The obtained photocatalytic Japanese paper 3 had a BET surface area of 2.5 m ² / g.
The resulting photocatalytic Japanese paper 3 is irradiated with light from a fluorescent lamp manufactured by Toshiba Lighting & Technology (Mellow 5N) having the same light intensity as in Example 2 to obtain a porous photocatalytic Japanese paper 3 having a BET surface area of 20.5 m ² / g. It was. At this time, the increase in the BET surface area per 1 g of the photocatalyst contained in the photocatalyst Japanese paper 3 can be calculated as about 180 m ² .

As a result of SEM observation of the photocatalytic Japanese paper 2 and the porous photocatalytic Japanese paper 2, it was observed that the photocatalytic titanium oxide covered the entire surface of the fibers in both Japanese papers.
When the deodorizing property of this porous photocatalyst Japanese paper 3 was evaluated, 100 ppm of acetaldehyde became 0 ppm (below the detection limit) after irradiation with black light. Moreover, the antifungal property of this porous photocatalytic Japanese paper 3 was good (◯), and the antibacterial property was also good (◯). Moreover, the light resistance of the porous photocatalyst Japanese paper 3 was good (◯).
Furthermore, when the deodorizing property was evaluated again using the porous photocatalyst Japanese paper 3 after the light resistance test, 100 ppm of acetaldehyde was 0 ppm (below the detection limit) after irradiation with black light, and the deodorizing performance was maintained.

[Reference Example 3]
When the photocatalytic Japanese paper 1 obtained in Example 1 was irradiated with light from a fluorescent lamp manufactured by Toshiba Lighting & Technology (Mellow 5N) having the same light intensity as in Example 2, the BET surface area slightly increased to 3.5 m ² / g. However, the increase in the BET surface area was very small compared to the photocatalytic Japanese paper 3 obtained in Example 3.

[Comparative Example 1]
A 10 cm × 10 cm Japanese paper with a BET surface area of 1.8 m ² / g was irradiated with light of a FL20SBLB type black light manufactured by Toshiba Lighting & Technology, which had the same intensity as in Example 1, but the BET surface area did not change.
When the deodorizing property of this Japanese paper was evaluated, 100 ppm of acetaldehyde was not changed to 100 ppm even after irradiation with black light. Further, this Japanese paper had a bad result (×) in both antifungal and antibacterial properties. Moreover, the light resistance test result of Japanese paper was yellowing (Δ), which was inferior to the light resistance (◯) of the photocatalytic Japanese paper obtained in Examples 1 to 3.

[Comparative Example 2]
A 10 cm × 10 cm Japanese paper was immersed in an aqueous dispersion of TKS203 (same as Reference Example 1) diluted with water to 5% by mass, and then dried at room temperature for 12 hours, whereby the photocatalytic content was about 10% by mass. 4 (photocatalyst fiber processed body 4) was prepared. The obtained photocatalytic Japanese paper 4 had a BET surface area of 20.5 m ² / g.
The resulting photocatalytic Japanese paper 4 was irradiated with light of a FL20SBLB type black light manufactured by Toshiba Lighting & Technology Co., Ltd. having the same intensity as in Example 1, but the BET surface area did not change to 20.5 m ² / g.
Moreover, the light resistance of the obtained photocatalyst Japanese paper 4 was a very bad result (x).

[Example 4]
The modified photocatalyst hydrosol (A-1) obtained in Reference Example 1 was diluted 10 times with water, immersed in a cotton fabric of 10 cm × 10 cm, and then dried at room temperature for 12 hours, whereby the photocatalyst content was about 1% by mass. Photocatalyst cotton fabric 1 (photocatalyst fiber processed body 4) was prepared. The resulting photocatalytic cotton fabric 1 had a BET surface area of 3.5 m ² / g.
The obtained photocatalyst cotton cloth 1 was irradiated with light of FL20SBLB type black light manufactured by Toshiba Lighting & Technology Co., Ltd. having the same light intensity as that of Example 1 to obtain a porous photocatalyst cotton cloth 1 having a BET surface area of 5.6 m ² / g. At this time, the increase in the BET surface area per gram of the photocatalyst contained in the photocatalyst cotton cloth 1 can be calculated as about 210 m ² .
The obtained porous photocatalyst cotton fabric 1 had a moisture absorption rate of 10.2%, and the result of the easy washing test was very good (◯).

[Comparative Example 3]
When the unwashed cotton fabric used in Example 4 was subjected to a washability test, the result was very bad (x).

  The porous photocatalyst fiber of the present invention is useful for the decomposition, removal and sterilization of various malodorous gases, harmful gases, harmful compounds, etc. generated in daily life over a long period of time, mold prevention, etc. It can be disassembled and maintain its appearance, and it can easily remove sebum stains by washing or washing with water, so it can be used for clothes, filters (especially for gases and liquids) that have environmental purification and antifouling performance, It can be used for interior materials, fixtures and accessories for buildings and vehicles.

Claims (18)

A photocatalyst fiber containing a photocatalyst (a), wherein the BET surface area is increased by 0.1 m ² / g or more by light irradiation. The photocatalyst fiber according to claim 1, wherein the BET surface area per 1 g of the photocatalyst (a) contained by light irradiation is increased by 10 m ² or more.   A composite compound (BC) in which a photocatalyst (a), a photocatalytic affinity organic component (B) that has a strong affinity for the photocatalyst and is decomposed by photocatalysis, and a hardly decomposable component (C) that is not easily decomposed by photocatalysis The photocatalyst fiber according to claim 1, further comprising:   A composite compound (BC) in which the photocatalyst (a) has a strong affinity for the photocatalyst and is combined with a photocatalytic affinity organic component (B) that is decomposed by photocatalysis and a hardly decomposable component (C) that is not easily decomposed by photocatalysis. The photocatalyst fiber according to claim 1, which contains a modified photocatalyst (A) that has been modified with the above.   5. The photocatalytic fiber according to claim 3, wherein the photocatalytic affinity organic component (B) has a polyoxyalkylene group.   The photocatalyst fiber according to any one of claims 1 to 5, wherein the photocatalyst (a) is a visible light responsive photocatalyst.   The photocatalyst fiber according to any one of claims 1 to 6, comprising a sensitizing dye. The porosity whose BET surface area increased 0.1 m < ² > / g or more by irradiating the photocatalyst fiber in any one of Claims 1-6 with the light of energy higher than the band gap energy of the photocatalyst (a) to contain. Photocatalytic fiber. The porous photocatalyst fiber whose BET surface area increased by 0.1 m < ² > / g or more by irradiating the photocatalyst fiber of Claim 7 with the absorption light of the contained sensitizing dye.   The porous photocatalyst fiber according to claim 8, which has an organic matter decomposing activity.   The porous photocatalytic fiber according to claim 8, which has antibacterial performance.   The porous photocatalytic fiber according to claim 8, wherein the porous photocatalytic fiber has antifungal performance.   The porous photocatalyst fiber according to claim 8, wherein the moisture absorption is 5 to 30%.   A fabric comprising the porous photocatalytic fiber according to claim 8.   A woven fabric comprising the porous photocatalytic fiber according to claim 8.   A knitted fabric comprising the porous photocatalytic fiber according to claim 8 or 9.   A nonwoven fabric comprising the porous photocatalytic fiber according to claim 8.   A paper comprising the porous photocatalytic fiber according to claim 8 or 9.