JP4507581B2 - Method for producing dye-containing mesoporous material - Google Patents

Description

  The present invention relates to a method for producing a dye-containing mesoporous material, and more particularly, to a method for producing a mesoporous material in which a skeleton is formed with metal atoms and oxygen atoms as main components and the dye is incorporated in the skeleton. .

  In recent years, as a material for adsorbing and storing various substances, mesoporous materials having meso-sized pores (mesopores) having a skeleton mainly composed of metal atoms and oxygen atoms and having a pore diameter of about 1 to 30 nm have been developed. Attention has been paid, and attempts have been made to introduce selective adsorption ability and specific catalytic function by introducing organic groups into the pore inner surface and skeleton of such mesoporous materials.

  As a method for introducing an organic group into the pore inner surface of such a mesoporous material, for example, silanol groups are described on the surface described in JP-A 2000-219770 (Patent Publication 1). A method of reacting trimethoxychlorosilane or methoxymercaptopropylsilane with a silica-based mesoporous material is known.

  However, in the conventional method in which an organic group can be introduced only into the pore inner surface of such a mesoporous material, it is generally sufficient to introduce an organic group such as a bulky dye into the pore. There is a problem that a sufficient amount of dye cannot be uniformly introduced because it does not diffuse.

In addition, as a method for introducing an organic group into the skeleton of a mesoporous material, for example, Japanese Patent Application Laid-Open No. 2000-219770 (Patent Document 1) has an organic group bonded to two or more metal atoms and those Describes a method for obtaining an organic / inorganic composite mesoporous material by polycondensation of an organometallic compound having an alkoxy group or a halogen group bonded to the metal atom under basic or acidic conditions. In Japanese Unexamined Patent Publication No. 2003-238118 (Patent Publication 2), a non-silica oxide skeleton is added to a solution containing a surfactant and an inorganic raw material by adding a silane compound linked with an organic functional group having a short alkyl chain length. Describes a method for obtaining a mesoporous material containing an organic functional group. Furthermore, B. Onida et al., “Permeability of micelles in surdactant-containing MCM-41 silica as monitored by embedded dye molecules”, Chem. Commun., (2001), p. 2216-2217 (Non-patent Document 1). Dye (Congo) in a basic solution of hexadecyltrimethylammonium bromide (CTAB)
Red) and tetraethylorthosilicate (TEOS) are mixed to obtain a mesoporous material containing a dye.

However, even with the conventional method of introducing an organic group into the skeleton of such a mesoporous material, there is a limit to the improvement of the introduction amount even if an organic group such as a bulky dye is generally introduced. There was a problem that a sufficient amount of dye could not be introduced.
JP 2000-219770 A JP 2003-238118 A B. Onida et al., "Permeability of micelles in surdactant-containing MCM-41 silica as monitored by embedded dye molecules", Chem. Commun., (2001), p.2216-2217

  The present invention has been made in view of the above-described problems of the prior art, and provides a method capable of producing a mesoporous material in which a sufficient amount of a dye is uniformly incorporated in a skeleton. Objective.

  As a result of intensive studies to achieve the above object, the present inventors firstly formed a metal alkoxide oligomer by subjecting a conjugate of a metal alkoxide and a dye and a metal alkoxide to a condensation reaction in an acidic solution to form an interface. To add a metal alkoxide oligomer to an alkaline solution containing an activator, a mesoporous material in which a sufficient amount of dye is uniformly incorporated in the skeleton is obtained, and the present invention is completed. It came.

That is, the method for producing the dye-containing mesoporous material of the present invention includes:
A first step of forming an alkoxysilane oligomer by subjecting the conjugate and the alkoxysilane to a condensation reaction in an acidic solution containing the alkoxysilane- dye conjugate and the alkoxysilane ;
In an alkaline solution containing said alkoxysilane oligomer and a surfactant, silica containing a dye allowed condensation reaction of the alkoxysilane oligomer together with the surfactant in the alkoxysilane oligomer allowed to form the introduced complex A second step of obtaining a porous mesoporous material ,
Only including,
The solvent of the acidic solution is a mixed solvent of water and an organic solvent;
The content of the organic solvent in the mixed solvent is 5 to 50% by weight,
The pH value of the solvent of the acidic solution is 6 or less,
The molar ratio of the conjugate to the alkoxysilane in the acidic solution (conjugate: alkoxysilane) is 1:30 to 1: 2.
The pH value of the solvent of the alkaline solution is 8 or more,
The concentration of the surfactant in the alkaline solution is 0.05 to 1 mol / L, and
The content of the alkoxysilane oligomer in the alkaline solution is 0.0055 to 0.33 mol / L in terms of metal concentration,
The method characterized by the above.

The reason why the mesoporous material in which a sufficient amount of the dye is uniformly incorporated in the skeleton can be obtained by the above-described method of the present invention is not necessarily clear, but the present inventors are as follows. I guess. In other words, first, a conjugate of an alkoxysilane and a dye is condensed with an alkoxysilane in an acidic solution to form a linear alkoxysilane oligomer, so that the dispersibility in the solution becomes very good. micelle formation in surfactant alkaline solution are allowed to coexist (alkoxysilane formation of a complex detergent is introduced into the oligomers) and alkoxy for the condensation reaction of the silane oligomer is to proceed uniformly and smoothly The present inventors speculate that a mesoporous material in which a sufficient amount of a dye is uniformly incorporated in the skeleton can be obtained.

Further, the method of manufacturing a dye-containing mesoporous material of the present invention, A alkoxysilane is used, a tetraalkoxysilane is preferable as such an alkoxysilane. Thus, a skeleton is formed with silicon atoms and oxygen atoms as main components, and a silica-based mesoporous material in which a sufficient amount of a dye is uniformly incorporated in the skeleton can be obtained.

  Moreover, in the manufacturing method of the pigment | dye containing mesoporous material of the said this invention, the 3rd process of removing the surfactant contained in the said pigment | dye containing mesoporous material may further be included. By further including such a third step, a dye-containing mesoporous material from which the surfactant in the pores has been sufficiently removed can be obtained.

Furthermore, in the method for producing a dye-containing mesoporous material of the present invention, it is preferable that an acidic mixed solvent of acid, water and an organic solvent is used as the acidic solution in the first step. When such an acidic mixed solvent is used, the dispersibility of the conjugate of the alkoxysilane and the dye in the solution is further improved, and the uniformity of the reaction between the conjugate and the alkoxysilane is improved. The amount of the dye incorporated in the skeleton tends to be higher. Further, the content of all alkoxysilanes in the acidic solution in the first step (the total amount of the alkoxysilane and the alkoxysilane in the conjugate) is 0.0055 to 0.33 mol / L in terms of metal concentration. Preferably there is.

  According to the method for producing a dye-containing mesoporous material of the present invention, it is possible to obtain a mesoporous material in which a sufficient amount of dye is uniformly incorporated in the skeleton.

  Hereinafter, the manufacturing method of the pigment | dye containing mesoporous material of this invention is demonstrated in detail in line with the suitable embodiment.

(First step)
In the method for producing a dye-containing mesoporous material of the present invention, first, a metal alkoxide oligomer is obtained by subjecting a conjugate of a metal alkoxide and a dye and an acid solution containing the metal alkoxide to a condensation reaction of the conjugate and the metal alkoxide. Is formed (first step).

  The metal alkoxide used here is not particularly limited as long as it can form a mesoporous material having a skeleton formed mainly of metal atoms and oxygen atoms by reaction, and is a metal element constituting the metal alkoxide. Is silicon, aluminum, titanium, magnesium, tantalum, niobium, molybdenum, cobalt, nickel, gallium, beryllium, yttrium, lanthanum, hafnium, tin, lead, iron, zinc, zirconium, vanadium, tungsten, boron, etc. Among these, silicon, aluminum, titanium, molybdenum, iron, zinc, zirconium, vanadium, tungsten and boron are preferable, and silicon is particularly preferable.

  The metal alkoxide includes a metal tetraalkoxide having 4 alkoxy groups (for example, tetraalkoxysilane), a metal trialkoxide having 3 alkoxy groups (for example, trialkoxysilane), and a metal dialkoxide having 2 alkoxy groups. (For example, dialkoxysilane) can be used. The type of alkoxy group is not particularly limited, but those having a relatively small number of carbon atoms in the alkoxy group (such as those having about 1 to 4 carbon atoms) such as methoxy group, ethoxy group, propoxy group, butoxy group, etc. This is advantageous in terms of reactivity. When the metal alkoxide has 3 or 2 alkoxy groups, an organic group, a hydroxyl group, or the like may be bonded to the metal atom in the metal alkoxide, and the organic group is an amino group, a mercapto group, or the like. It may further have a functional group.

  Specific examples of such metal alkoxides include tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, and dimethoxydiethoxysilane; trimethoxysilanol, triethoxysilanol, and trimethoxy. Methylsilane, trimethoxyvinylsilane, triethoxyvinylsilane, 3-glycidoxypropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, 3- (2-aminoethyl) aminopropyltrimethoxysilane , Phenyltrimethoxysilane, phenyltriethoxysilane, γ- (methacryloxypropyl) trimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane Trialkoxysilanes such as orchid; dialkoxysilanes such as dimethoxydimethylsilane, diethoxydimethylsilane, diethoxy-3-glycidoxypropylmethylsilane, dimethoxydiphenylsilane, dimethoxymethylphenylsilane; titanium ethoxide, titanium isoporoxide And titanium alkoxides such as titanium butoxide; aluminum alkoxides such as aluminum ethoxide, aluminum isoporopoxide, and aluminum butoxide; zirconium alkoxides such as zirconium methoxide and zirconium ethoxide.

  Although the said metal alkoxide can also be used independently, it is also possible to use it in combination of 2 or more types. In addition, when using in combination of 2 or more types as a metal alkoxide, it is preferable to use an alkoxysilane as at least one of them. The metal alkoxide having 2 to 4 alkoxy groups can be used in combination with a metal monoalkoxide having one alkoxy group (for example, monoalkoxysilane). Specific examples of the metal monoalkoxide that can be used in this manner include trimethylmethoxysilane, trimethylethoxysilane, 3-chloropropyldimethylmethoxysilane, and the like.

  When alkoxysilane is used as such a metal alkoxide, the alkoxysilane generates a silanol group by hydrolysis, and the generated silanol groups are condensed to form a silicon oxide. In this case, an alkoxysilane having a large number of alkoxy groups in the molecule has many bonds generated by hydrolysis and condensation. Therefore, it is preferable to use tetraalkoxysilane having a large number of alkoxy groups as alkoxysilane, and it is particularly preferable to use tetramethoxysilane or tetraethoxysilane as the tetraalkoxysilane from the viewpoint of reaction rate.

  In the present invention, a conjugate of a metal alkoxide and a dye is used together with the metal alkoxide. The metal alkoxide constituting the conjugate is also the same as the metal alkoxide, and the same metal alkoxide as the metal alkoxide used is dyed. It is preferable to use a conjugate in which is bound.

  The dye that can be used in the present invention is not particularly limited as long as it is a dye that absorbs light having a predetermined wavelength, and is appropriately selected depending on the light to be irradiated, the metal alkoxide to be combined, and the like. Examples of such dyes include azo dyes, toluidine dyes, anthraquinone dyes, indigoid dyes, sulfur dyes, triphenylmethane dyes, pyrazolone dyes, stilbene dyes, diphenylmethane dyes, xanthene dyes, alizarin dyes, acridine dyes, quinoneimine dyes (azine dyes). , Oxazine dyes, thiazine dyes), thiazole dyes, methine dyes, nitro dyes, nitroso dyes, cyanine dyes and the like. Disperse Red 1 [compound name: 4- (N- 2-hydroxyethyl-N-ethyl) amino-4′-nitroazobenzene], Disperse Orange 3 [compound name: 4- (4-nitrophenylazo) aniline], Disperse Red 19 [compound name: 4 Intramolecular charge transfer type azo dyes such as (N, N-di (2-hydroxyethyl)) amino-4′-nitroazobenzene] (monoazo dyes, disazo dyes, trisazo dyes, tetrakisazo dyes, polyazo dyes), cyanine System dyes are preferred.

  Furthermore, the bonding form of the metal alkoxide and the dye is not particularly limited, but is preferably bonded by a covalent bond from the viewpoint of relatively strong bonding, such as an amide group, an alkylamide group, an ester group, etc. It is illustrated that they are connected via each other.

  As a conjugate of such a metal alkoxide and a dye, if there is a commercially available product, the commercially available product may be used as it is, or a conjugate synthesized by combining a metal alkoxide and a pigment by a known reaction method. It may be used. Thus, the synthesis method and the conditions for bonding the metal alkoxide and the dye are not particularly limited, and are appropriately selected according to the dye and the metal alkoxide to be used. For example, when a dye having a hydroxyl group is used, a metal alkoxide to which an isocyanato group, an isocyanatoalkyl group, a carboxyl group, and the like are bonded and the dye are heated in a solvent (for example, an organic solvent such as pyridine, acetone, or ether). A preferable method is a method of reacting under conditions (for example, 40 to 100 ° C.).

  In the first step of the present invention, the metal alkoxide and the conjugate are subjected to a condensation reaction in an acidic solution to form a metal alkoxide oligomer. In this first step, water or water and an organic solvent are used. It is preferable to use the above mixed solvent as a solvent, and it is more preferable to use a mixed solvent of water and an organic solvent, particularly when a highly hydrophobic dye is used. When such a mixed solvent is used, the dispersibility of the conjugate of the metal alkoxide and the dye in the solution is further improved and the uniformity of the reaction is improved, so that it is incorporated in the skeleton of the obtained mesoporous material. The amount of dye tends to be higher. Examples of the organic solvent suitably used here include acetone, alcohol, and the like. The content of the organic solvent in the mixed solvent is not particularly limited and varies depending on the pigment to be introduced, but is about 5 to 50% by weight. It is illustrated that. If the content of the organic solvent is less than the above lower limit, the above-described dispersibility and reaction uniformity tend not to be sufficiently improved. On the other hand, if it exceeds the above upper limit, the reaction uniformity with the alkoxide tends to decrease. is there.

  Further, the solvent used in the first step needs to be acidic at pH 6 or less, and is preferably in the range of pH 2-5. If the pH is too low, problems such as reaction of the dye itself tend to occur. Moreover, as an acid used when making a solvent acidic, mineral acids, such as hydrochloric acid, nitric acid, and a sulfuric acid, etc. are mentioned.

  Furthermore, the content of the total metal alkoxide in the acidic solution in the first step (the total amount of the metal alkoxide and the metal alkoxide in the conjugate) is 0.0055 to 0.33 mol / L in terms of metal concentration. It is preferable. The ratio of the conjugate to the metal alkoxide is preferably 1:30 to 1: 2 in terms of the conjugate: metal alkoxide value (molar ratio). If the content of the conjugate is less than the lower limit, the amount of the dye contained in the obtained mesoporous material tends not to be sufficiently improved. On the other hand, if the content exceeds the upper limit, a porous body having a periodic structure is produced. It tends to be impossible.

  In addition, the conditions (temperature, time, etc.) for the condensation reaction between the metal alkoxide and the conjugate in the first step are not particularly limited, and the improvement in dispersibility is optimal depending on the raw materials used. In general, the acidic solution containing the metal alkoxide and the conjugate for about 1 to 10 hours at a temperature of about 0 to 100 ° C. (more preferably 20 to 80 ° C.) is generally used. It is preferable to stir.

  The metal alkoxide oligomer obtained in the first step is obtained by hydrolysis and condensation reaction of the metal alkoxide and the conjugate. When the metal alkoxide is an alkoxysilane, it becomes an alkoxysilane oligomer. The degree of polymerization of the metal alkoxide oligomer is not particularly limited, but it is generally preferable that the dispersibility is optimal.

(Second step)
Next, in the method for producing a dye-containing mesoporous material of the present invention, a complex in which the surfactant is introduced into the metal alkoxide oligomer in an alkaline solution containing the metal alkoxide oligomer and the surfactant. At the same time, the metal alkoxide oligomer is subjected to a condensation reaction to obtain a mesoporous material containing a dye (second step).

  The surfactant used here is not particularly limited, and may be any of cationic, anionic, and nonionic. Specifically, alkyltrimethylammonium, alkylammonium, Chlorides, bromides, iodides or hydroxides such as dialkyldimethylammonium and benzylammonium; fatty acid salts, alkylsulfonates, alkylphosphates, polyethylene oxide nonionic surfactants, primary alkylamines, etc. . These surfactants may be used alone or in combination of two or more.

Among the above surfactants, examples of the polyethylene oxide nonionic surfactant include a polyethylene oxide nonionic surfactant having a hydrocarbon group as a hydrophobic component and polyethylene oxide as a hydrophilic portion. . Such surfactants, for example, is represented by the general formula _{C n H 2n + 1 (OCH} 2 CH 2) m OH, n is 10 to 30, m can be used favorably those which are 30 . As such a surfactant, an ester of a fatty acid such as oleic acid, lauric acid, stearic acid, palmitic acid and sorbitan, or a compound obtained by adding polyethylene oxide to these esters can also be used.

Further, as such a surfactant, a triblock copolymer type polyalkylene oxide may be used. Examples of such surfactants include those composed of polyethylene oxide (EO) and polypropylene oxide (PO) and represented by the general formula (EO) _x (PO) _y (EO) _x . x and y represent the number of repetitions of EO and PO, respectively, x is preferably 5 to 110, y is preferably 15 to 70, x is preferably 13 to 106, and y is more preferably 29 to 70. Examples of the triblock copolymer include (EO) ₁₉ (PO) ₂₉ (EO) ₁₉ , (EO) ₁₃ (PO) ₇₀ (EO) ₁₃ , (EO) ₅ (PO) ₇₀ (EO) ₅ , (EO). ₁₃ (PO) ₃₀ (EO) ₁₃ , (EO) ₂₀ (PO) ₃₀ (EO) ₂₀ , (EO) ₂₆ (PO) ₃₉ (EO) ₂₆ , (EO) ₁₇ (PO) ₅₆ (EO) ₁₇ , ( EO) ₁₇ (PO) ₅₈ (EO) ₁₇ , (EO) ₂₀ (PO) ₇₀ (EO) ₂₀ , (EO) ₈₀ (PO) ₃₀ (EO) ₈₀ , (EO) ₁₀₆ (PO) ₇₀ (EO) ₁₀₆ , (EO) ₁₀₀ (PO) ₃₉ (EO) ₁₀₀ , (EO) ₁₉ (PO) ₃₃ (EO) ₁₉ , (EO) ₂₆ (PO) ₃₆ (EO) ₂₆ . These triblock copolymers are available from BASF, Aldrich, etc., and triblock copolymers having desired x and y values can be obtained at a small scale production level.

Also, a star diblock copolymer in which two polyethylene oxide (EO) chains-polypropylene oxide (PO) chains are bonded to two nitrogen atoms of ethylenediamine can be used. Examples of such star diblock copolymers include those represented by the general formula ((EO) _x (PO) _y ) ₂ NCH ₂ CH ₂ N ((PO) _y (EO) _x ) ₂ . Here, x and y represent the number of repetitions of EO and PO, respectively, x is preferably 5 to 110, y is preferably 15 to 70, x is 13 to 106, and y is 29 to 70. preferable.

Among such surfactants, a mesoporous material with high crystallinity can be obtained, and therefore a salt of alkyltrimethylammonium [C _p H _{2p + 1} N (CH ₃ ) ₃ ] (preferably a halide salt). Is preferably used. In that case, the alkyl group in the alkyltrimethylammonium preferably has 8 to 22 carbon atoms. Examples include octadecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, tetradecyltrimethylammonium chloride, dodecyltrimethylammonium bromide, decyltrimethylammonium bromide, octyltrimethylammonium bromide, docosyltrimethylammonium chloride, and the like. It is done.

  In the second step of the present invention, the metal alkoxide oligomer is reacted in an alkaline solution containing the surfactant. In this second step, water, an organic solvent (acetone, alcohol, etc.), water A mixed solvent of water and an organic solvent can be used, but it is preferable to use water or a mixed solvent containing water as a main component.

  Further, the solvent used in the second step needs to be alkaline having a pH of 8 or more, and is preferably in the range of pH 9-11. If the pH of the solvent is less than 8, it is difficult to stably form mesopores by the reaction. On the other hand, if the pH is too high, problems such as deterioration of the dye due to the reaction tend to occur. Examples of the base used for making the solvent alkaline include sodium hydroxide, ammonium hydroxide, potassium hydroxide and the like.

  Furthermore, the concentration of the surfactant in the alkaline solution in the second step is preferably 0.05 to 1 mol / L. When this concentration is less than the lower limit, surfactant ions are not sufficiently introduced into the metal alkoxide oligomer and the formation of pores tends to be incomplete. On the other hand, when the upper limit is exceeded, unreacted solution There is a tendency that the amount of surfactant remaining therein increases and the uniformity of the pores decreases. Further, the content of the metal alkoxide oligomer in the alkaline solution is preferably 0.0055 to 0.33 mol / L in terms of metal concentration. If the content of the metal alkoxide oligomer is less than the above lower limit, the amount of the surfactant that remains unreacted in the solution tends to increase and the uniformity of the pores tends to decrease. Surfactant ions are not sufficiently introduced into the metal alkoxide oligomer and the pore formation tends to be incomplete. Furthermore, it is preferable that the number of moles of metal atoms contributing to skeleton formation is 0.02 to 10 times the number of moles of surfactant.

  In addition, the conditions (temperature, time, etc.) for reacting the metal alkoxide oligomer in the alkaline solution containing the surfactant in the second step are not particularly limited, and the metal alkoxide oligomer and surfactant used, etc. The mesopore structure is stably prepared according to the above, and is appropriately selected so that the dye portion is sufficiently taken in. Generally, the temperature is about 0 to 100 ° C. (more preferably 20 to 80 ° C.). It is preferable that the alkaline solution containing the metal alkoxide oligomer and the surfactant is aged for 5 to 30 hours with stirring. Furthermore, after allowing the system to stabilize as necessary, a mesoporous material can be obtained by filtering, washing and drying the resulting precipitate.

  In such a second step, the surfactant forms micelles regularly arranged in an alkaline solution, and the metal alkoxide oligomer assembles around the micelle, and the surfactant is introduced into the metal alkoxide oligomer. The formed complex is formed. Then, a reactive hydroxyl group (—O—H) (silanol group in the case where the metal alkoxide is an alkoxysilane) formed by hydrolysis of the metal alkoxide in the composite thus formed is subjected to a condensation reaction (dehydration condensation). And a mesoporous material in which a metal alkoxide bond is partially formed to have a two-dimensional or three-dimensional network structure and the dye is incorporated in the skeleton (in the case where the metal alkoxide is an alkoxysilane, a silica-based mesoporous material). Body) is obtained.

(Third process)
In the method for producing a dye-containing mesoporous material of the present invention, the surfactant contained in the dye-containing mesoporous material obtained by the second step described above may be removed (third step). As a method for removing the surfactant in this way, for example, (i) the surfactant is removed by immersing the dye-containing mesoporous material in an organic solvent (for example, ethanol) having high solubility in the surfactant. Method, (ii) a method of removing the surfactant by baking the dye-containing mesoporous material at 300 to 1000 ° C., and (iii) immersing the dye-containing mesoporous material in an acidic solution and heating the surfactant An ion exchange method in which is exchanged with hydrogen ions, and the like can be mentioned, but the method (i) is preferred from the viewpoint of preventing decomposition of the dye by heating. By further including such a third step, a dye-containing mesoporous material from which the surfactant in the pores has been sufficiently removed can be obtained. In the case of the method (i), in order to stabilize the inner wall inner structure of the dye-containing mesoporous material, heat treatment (preferably at 50 to 100 ° C. for about 1 to 10 hours) may be performed.

  In the method for producing a dye-containing mesoporous material of the present invention described above, in the first step described above, first, a conjugate of a metal alkoxide and a dye is subjected to a condensation reaction together with the metal alkoxide in an acidic solution to form a linear form. Dispersibility in the solution is greatly improved by using the metal alkoxide oligomer. Therefore, in the subsequent second step, micelle formation (formation of complex in which surfactant is introduced into metal alkoxide oligomer) and condensation reaction of metal alkoxide oligomer in the alkaline solution coexisting with surfactant. Can progress uniformly and smoothly, and a mesoporous material in which a sufficient amount of dye is uniformly incorporated in the skeleton can be obtained.

(Dye-containing mesoporous material)
The mesoporous material obtained by the production method of the present invention uses the metal alkoxide oligomer obtained by condensation reaction of the metal alkoxide and the conjugate in the acidic solution as a raw material, and the alkaline using the surfactant as a template. It is a mesoporous material produced in a solution and having a network structure in which metal atoms are bonded via oxygen atoms as a basis and highly crosslinked in the pore walls. Examples of such metal oxides include metal oxides (including semi-metal oxides) such as silica, alumina, titania, zirconia, ceria, tin oxide, barium oxide, nickel oxide, ruthenium oxide, vanadium oxide, and indium oxide. Among them, metal oxides that are transparent to visible light, such as silica and alumina, are preferred because they have a wide range of choice when used in combination with a dye.

The pore diameter (average pore diameter), specific surface area, etc. of the mesoporous material obtained by the production method of the present invention are not particularly limited and are appropriately selected according to the purpose of use, etc., but are average from the viewpoint of improving adsorption efficiency. It is preferable to make the pore diameter equal to or larger than the molecular size of the substance to be adsorbed and to increase the specific surface area as much as possible. From such a viewpoint, as the mesoporous material obtained by the present invention, those having an average pore diameter of about 0.3 nm to 100 nm and a specific surface area of about 100 m ² / g or more are preferable. A mesoporous material is particularly preferred.

  Such a silica-based mesoporous material is produced using a surfactant as a template and a silica source as a raw material, and is based on a skeleton —Si—O— in which silicon atoms are bonded via oxygen atoms, and is highly sophisticated. It has a crosslinked network structure. Such a silica-based material only needs to have silicon atoms and oxygen atoms as main components, and at least a part of the silicon atoms may form a carbon-silicon bond at two or more organic groups. . Examples of such an organic group include, but are not limited to, divalent or higher organic groups generated by removing two or more hydrogens from hydrocarbons such as alkanes, alkenes, alkynes, benzenes, and cycloalkanes. Instead, the organic group may have an amide group, amino group, imino group, mercapto group, sulfone group, carboxyl group, ether group, acyl group, vinyl group or the like.

  The silica-based mesoporous material suitable for the present invention has mesopores having a central pore diameter of about 1 to 100 nm in the pore size distribution curve. In the case of having such mesopores, a functional organic compound having a large molecular diameter can easily enter the pores, and the diffusion of molecules within the pores can be performed quickly, so that the efficiency can be improved. Good adsorption separation tends to be possible. The central pore diameter is a curve (pore diameter distribution curve) in which a value (dV / dD) obtained by differentiating the pore volume (V) with respect to the pore diameter (D) is plotted against the pore diameter (D). ) At the maximum peak, and can be determined by the method described below. That is, the silica-based mesoporous material is cooled to a liquid nitrogen temperature (−196 ° C.), nitrogen gas is introduced, the adsorption amount is determined by a constant volume method or a gravimetric method, and then the pressure of the introduced nitrogen gas is gradually increased. Increase and plot the amount of nitrogen gas adsorbed against each equilibrium pressure to obtain an adsorption isotherm. Using this adsorption isotherm, a pore size distribution curve can be obtained by a calculation method such as Cranston-Inklay method, Pollimore-Heal method, BJH method or the like.

The silica-based mesoporous material suitable for the present invention preferably contains 60% or more of the total pore volume in the range of ± 40% of the center pore diameter in the pore size distribution curve. A silica-based mesoporous material that satisfies this condition means that the pore diameter is very uniform. The specific surface area of the silica mesoporous material is not particularly limited, but is preferably 700 m ² / g or more. The specific surface area can be calculated as a BET specific surface area from the adsorption isotherm using the BET isotherm adsorption equation.

  Furthermore, the silica-based mesoporous material suitable for the present invention preferably has one or more peaks at a diffraction angle corresponding to a d value of 1 nm or more in the X-ray diffraction pattern. The X-ray diffraction peak means that a periodic structure having a d value corresponding to the peak angle is present in the sample. Therefore, having one or more peaks at a diffraction angle corresponding to a d value of 1 nm or more means that the pores are regularly arranged at intervals of 1 nm or more.

  Further, the pores of the silica-based mesoporous material suitable for the present invention are formed not only on the surface of the porous material but also on the inside. The arrangement state (pore arrangement structure or structure) of the pores in such a porous body is not particularly limited, but is preferably a 2d-hexagonal structure, a 3d-hexagonal structure, or a cubic structure. Such a pore arrangement structure may have a disordered pore arrangement structure.

Here, that the porous body has a hexagonal pore arrangement structure means that the arrangement of the pores is a hexagonal structure (S. Inagaki, et al., J. Chem. Soc., Chem. Commun. 680, 1993; S. Inagaki, et al., Bull. Chem. Soc. Jpn., 69, 1449; 1996, Q. Huo, et al., Science, 268, 1324, 1995). Further, the porous body having a cubic pore arrangement structure means that the arrangement of pores is a cubic structure (JCVartuli, et al., Chem. Mater., 6, 2317, 1994; Q. Huo). , et al., Nature, 368, 317, 1994). Further, the porous body having a disordered pore arrangement structure means that the arrangement of the pores is irregular (PTTanev, et al., Science, 267, 865, 1995; SABagshaw, et.
al., Science, 269, 1242, 1995; R. Ryoo, et al., J. Phys. Chem., 100, 17718, 1996). The cubic structure is preferably Pm-3n, Im-3m or Fm-3m symmetric. The symmetry is determined based on a space group notation.

  The silica-based mesoporous material suitable for the present invention may be used as a powder having an average particle size of about 0.01 to 3 μm, but may be molded and used as necessary. Any molding means may be used, but extrusion molding, tablet molding, rolling granulation, compression molding, CIP and the like are preferable. The shape can be determined according to the use mode and method, and examples thereof include a columnar shape, a crushed shape, a spherical shape, a honeycomb shape, an uneven shape, and a corrugated shape.

  The dye-containing mesoporous material obtained by the production method of the present invention is one in which the dye is uniformly incorporated in the skeleton of the mesoporous material. Thus, the content of the dye incorporated in the skeleton of the mesoporous material is not particularly limited. However, according to the production method of the present invention, a sufficient amount of the dye can be incorporated into the skeleton. It is preferably about 2 to 30% by weight of the porous body. If the content of the dye is less than the lower limit, the effect exerted by containing the dye (for example, the difference in the amount of adsorption due to the presence or absence of light irradiation) tends not to be sufficiently exhibited, whereas, if the upper limit is exceeded, The adsorption performance of the mesoporous material tends to decrease and the adsorption amount tends to be insufficient. Further, in the dye-containing mesoporous material obtained by the production method of the present invention, since the dye is incorporated in the skeleton, the detachment of the dye is reliably prevented.

  In the dye-containing mesoporous material obtained by the production method of the present invention, a substance to be adsorbed thereon (for example, a gas such as hydrogen, carbon monoxide, carbon dioxide, nitrogen, hydrocarbon (gas), halomethane, etc.) The amount of adsorbed liquid component such as water, hydrocarbon (liquid), gasoline, etc.) is irradiated with light having a wavelength that is absorbed by the pigment (hereinafter referred to as “light irradiation state”) It is surprisingly different from the case of not irradiating such light (hereinafter referred to as “light irradiation stopped state”), and the adsorption amount can be reduced reversibly by repeating the light irradiation state and the light irradiation stopped state. It can be actively changed. Therefore, the dye-containing mesoporous material obtained by the production method of the present invention achieves hydrogen separation, carbon monoxide separation, carbon dioxide separation, nitrogen separation, hydrocarbon separation, removal of harmful substances such as halomethane, humidity control, and the like. Useful for the system.

  The reason why the adsorption amount reversibly changes by changing the light irradiation amount in this way is not necessarily clear, but the present inventors infer as follows. That is, when irradiation of light having a wavelength to a mesoporous material containing a dye that absorbs light having a predetermined wavelength is started or the amount of irradiation is increased, there is no change in the ground state of molecules excited by light absorption. The temperature inside the dye-containing mesoporous material slightly rises due to radiation transition or reversible photoreaction, thereby reducing the amount of adsorbed substance adsorbed on the dye-containing mesoporous material (adsorption equilibrium amount). On the other hand, when the irradiation of such light is stopped or the irradiation amount is reduced, the temperature inside the dye-containing mesoporous material quickly decreases to a temperature without such non-radiative transition or reversible photoreaction, thereby containing the dye. The amount of adsorbed substance that can be adsorbed on the mesoporous material (adsorption equilibrium amount) increases. And the transitional change in the equilibrium state of the adsorption performance of the dye-containing mesoporous material by light irradiation is not accompanied by an irreversible so-called photochemical reaction, but is caused by a reversible change in so-called physical adsorption characteristics. Therefore, the present inventors infer that the adsorption amount reversibly changes by repeating the light irradiation state and the light irradiation stopped state. The temperature rise inside the dye-containing mesoporous material is a slight temperature change in a minute region near the surface of the dye-containing mesoporous material, and the temperature rise of the entire system in the conventional heating swing cycle adsorption technique Are quite different and differ greatly in terms of time to reach equilibrium, energy loss, local control, and the like. Further, the present inventors speculate that the amount of adsorption reversibly changes depending on the increase or decrease of the amount of the transient structural change component of the dye due to the increase or decrease of the light irradiation amount or the polarity change of the surface of the dye-containing mesoporous material.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

Example 1
Azo dyes {Aldrich Disperse Red 1 (DR1) [compound name: 4- (N-2- hydroxyethyl -N- ethyl) amino-4'-nitroazobenzene]} alkoxysilane {triethoxysilane (ICP TEOS) } As a conjugate with the following structural formula:

An alkoxysilane having an azobenzene skeleton represented by the formula (DR1UPTEOS) was used. Then, 0.76 g of acetone and 0.83 g of 0.01 N hydrochloric acid were added to a mixture {DR1UPTEOS: TEOS = 1: 30 (molar ratio)} of DR1UPTEOS 0.081 g and TEOS 0.903 g, and room temperature (about 25 ° C.) was added. And stirred. At first, DR1UPTEOS dissolved in TEOS and acetone was dispersed, but after about 1 hour of reaction, it turned into a homogeneous solution, and when reacted for about 3 hours, it accompanied with oligomer formation by hydrolysis and dehydration condensation of TEOS and DR1UPTEOS. An increase in viscosity was observed.

On the other hand, 0.7 mL of 2.02 M aqueous sodium hydroxide solution was mixed with 90 mL of distilled water, and trimethylstearyl ammonium chloride {[CH ₃ (CH ₂ ) ₁₇ N (CH ₃ ) ₃ ] Cl (C18TMACl)} 0. After adding 200 g and heating to 40 ° C. to dissolve, it was kept at room temperature.

  Subsequently, when the said oligomer solution was dripped at the obtained alkaline surfactant aqueous solution, stirring vigorously, the solution became cloudy simultaneously with dripping. The mixture was further stirred at room temperature for about 2.5 hours, and then filtered using a Kiriyama funnel. The filtrate was almost colorless and transparent, and when the obtained red powder (pigment-containing mesoporous material) was rinsed with water and acetone, the filtrate showed a slight pink color during the acetone rinse.

  Subsequently, in order to remove C18TMACl as a template from the obtained dye-containing mesoporous material, the mesoporous material was suspended in a solution obtained by adding 2.0 g of concentrated hydrochloric acid to 100 mL of ethanol, and stirred at room temperature for about 7 hours. Then, it filtered using the Kiriyama funnel. Furthermore, the obtained powder was rinsed with ethanol, water, and acetone, air-dried, and then vacuum-dried overnight to obtain a dye-containing mesoporous material from which the surfactant in the pores was sufficiently removed.

(Example 2)
The surfactant is sufficiently removed in the same manner as in Example 1 except that a mixture of DR1UPTEOS 0.229 g and TEOS 0.852 g {DR1UPTEOS: TEOS = 1: 10 (molar ratio)} is used as a mixture of DR1UPTEOS and TEOS. A dye-containing mesoporous material was obtained.

First, an azo dye {Disperse Red 19 (DR19) [compound name: 4- (N, N-di (2-hydroxyethyl)) amino-4'-nitroazobenzene] manufactured by Aldrich Co.]} and 2 equivalents of alkoxysilane { tri An alkoxysilane (DR19TEOS) having an azobenzene skeleton that is a conjugate with ethoxysilane ( ICP TEOS)} is represented by the following reaction formula:

Was synthesized according to That is, first, DR19 was purified by suspending commercially available DR19 in hot acetone, filtering off the hot acetone soluble part, and recrystallizing the crystals obtained by concentrating the filtrate using ethanol. did. Further, extraction with hot acetone was repeatedly performed on the hot acetone insoluble part. Next, to the pyridine solution (30 mL) containing 5.07 g (15.3 mmol) of DR19 and heated to 50 to 60 ° C., 9.57 g (38.7 mmol) of 3-isocyanato represented by the above reaction formula was used. A pyridine solution (20 mL) containing propyltriethoxysilane (ICPTEOS) was added dropwise, and the mixture was stirred for 7 hours while being heated to 50 to 60 ° C. Next, when the reaction solution was analyzed by TLC, DR19 remained in the solution. Therefore, a pyridine solution (10 mL) containing 1.1 equivalent (3.05 g) of ICPTEOS was further added, and the temperature was further increased to 50 to 60 ° C. The mixture was stirred for 7 hours while heated. After the reaction, pyridine was distilled off from the reaction solution under reduced pressure, and then purified by column chromatography (developing solvent: ethyl acetate / hexane = 1/1), and DR19TEOS (6.60 g, 8.00 mmol) shown in the above reaction formula. Yield 52%). In addition, it was confirmed by measurement of ¹ H and ¹³ C NMR spectra that the obtained compound had the structure of DR19TEOS shown in the above reaction formula.

  Next, 0.76 g of acetone and 0.83 g of 0.01 N hydrochloric acid are added to a mixture of DR19TEOS 0.12 g and TEOS 0.90 g {DR19TEOS: TEOS = 1: 30 (molar ratio)}, and the mixture is brought to room temperature (about 25 ° C.). And stirred. At first, DR19TEOS dissolved in TEOS and acetone was dispersed, but after about 1 hour of reaction, it turned into a homogeneous solution, and when reacted for about 3 hours, it accompanied the hydrolysis and dehydration condensation of TEOS and DR19TEOS. An increase in viscosity was observed.

On the other hand, 0.7 mL of 2.02 M aqueous sodium hydroxide solution was mixed with 90 mL of distilled water, and trimethylstearyl ammonium chloride {[CH ₃ (CH ₂ ) ₁₇ N (CH ₃ ) ₃ ] Cl (C18TMACl)} 0. After adding 200 g and heating to 40 ° C. to dissolve, it was kept at room temperature.

  Subsequently, when the said oligomer solution was dripped at the obtained alkaline surfactant aqueous solution, stirring vigorously, the solution became cloudy simultaneously with dripping. The mixture was further stirred at room temperature for about 2.5 hours, and then filtered using a Kiriyama funnel. The filtrate was colorless and transparent. When the obtained red powder (pigment-containing mesoporous material) was rinsed with water and acetone, the filtrate was transparent during the acetone rinse. In this way, a dye-containing mesoporous material having a surfactant in the pores was obtained.

Example 4
A surfactant is contained in the pores in the same manner as in Example 3 except that a mixture of DR19TEOS 0.34 g and TEOS 0.85 g {DR19TEOS: TEOS = 1: 10 (molar ratio)} is used as a mixture of DR19TEOS and TEOS. An existing dye-containing mesoporous material was obtained.

(Comparative Example 1)
A mesoporous material for comparison was obtained in the same manner as in Example 1 except that only 0.933 g of TEOS was used instead of the mixture of DR1UPTEOS and TEOS. In addition, when the oligomer solution was dropped into the surfactant aqueous solution, the solution became cloudy, and the obtained powder was a white powder.

(Comparative Example 2)
2 mL of 2M aqueous sodium hydroxide solution was mixed with 290 mL of distilled water, and then trimethylstearyl ammonium chloride {[CH ₃ (CH ₂ ) ₁₇ N (CH ₃ ) ₃ ] Cl (C18TMACl)} 0.6 g was added to the mixture. After heating to 0 ° C. to dissolve, it was kept at room temperature.

  Next, DR1UPTEOS 0.081 g, TEOS 0.907 g {DR1UPTEOS: TEOS = 1: 30 (molar ratio)} and acetone 0.25 g were added dropwise with stirring to the obtained alkaline surfactant aqueous solution, and the solution turned red. However, the dropped liquid was separated into droplets, and the solution became red turbid after stirring for about 10 minutes. The mixture was further stirred at room temperature for about 2.5 hours, and then filtered using a Kiriyama funnel. The filtrate is light pink, and when the obtained red powder (mesoporous material) is rinsed with water and acetone, the filtrate is initially red, and until the filtrate is colorless and transparent, The rinse was repeated. In this way, a mesoporous material for comparison in which a surfactant is present in the pores was obtained.

(Comparative Example 3)
Comparative Example 2 except that 0.232 g of DR1UPTEOS, 0.846 g of TEOS {DR1UPTEOS: TEOS = 1: 10 (molar ratio)} and 0.5 g of acetone were added dropwise with stirring to an alkaline surfactant aqueous solution. A comparative mesoporous material with a surfactant present in the pores was obtained.

(Comparative Example 4)
A comparative mesoporous material in which a surfactant is present in the pores was obtained in the same manner as in Comparative Example 2 except that only 0.915 g of TEOS was added dropwise to an aqueous alkaline surfactant solution while stirring. When TEOS was dropped into the surfactant aqueous solution, the solution became cloudy after stirring for about 15 minutes, and the obtained powder was a white powder.

(Infrared absorption spectrum measurement)
The infrared (IR) absorption spectra of the mesoporous materials obtained in Examples 1 and 2 were measured by the KBr method using a Fourier transform infrared spectrometer (manufactured by Nicolet: Avatar 360). Infrared absorption spectra of the mesoporous materials obtained in Example 1 and Example 2 are shown in FIGS. 1 (a) and 1 (b), respectively. From the results shown in FIGS. 1 (a) and 1 (b), it was confirmed that the mesoporous materials obtained in Examples 1 and 2 were based on a silica skeleton and were introduced with an azo dye.

  Moreover, when the infrared (IR) absorption spectrum was similarly measured also about the mesoporous material obtained in Examples 3-4, absorption derived from a pigment | dye was observed and the mesoporous material obtained in Examples 3-4 In the same manner as in the mesoporous materials obtained in Examples 1 and 2, it was confirmed that the material was based on a silica skeleton and into which an azo dye was introduced.

  On the other hand, when the infrared (IR) absorption spectrum was similarly measured for the mesoporous materials obtained in Comparative Examples 2 to 3, almost no absorption derived from the dye was observed, and the mesopores obtained in Comparative Examples 2 to 3 were observed. It was confirmed that only a small amount of dye was introduced into the porous material as compared with the mesoporous material obtained in Examples 1 to 4.

(X-ray diffraction measurement)
The X-ray diffraction (XRD) patterns of the mesoporous materials obtained in Examples 1-2 and Comparative Example 1 were measured using an X-ray diffraction apparatus (RINT-TTR, manufactured by Rigaku). The X-ray diffraction patterns of the mesoporous materials obtained in Comparative Example 1, Example 1 and Example 2 are shown in FIGS. 2 (a), 2 (b) and 2 (c), respectively. From the results shown in FIGS. 2 (a), (b), and (c), the mesoporous materials obtained in Examples 1 and 2 and Comparative Example 1 have diffraction peaks and are made of a material having a periodic structure. It was confirmed that there was. Moreover, it is guessed from the indexing that it is a two-dimensional hexagonal structure.

  Moreover, the X-ray diffraction (XRD) pattern was similarly measured about the mesoporous material obtained in Examples 3-4. The X-ray diffraction pattern of the mesoporous material obtained in Comparative Example 1, Example 3 and Example 4 is shown in FIG. From the results shown in FIG. 3, it was confirmed that the mesoporous material obtained in Examples 3 to 4 and Comparative Example 1 had a diffraction peak and was a material having a periodic structure. Moreover, it is guessed from the indexing that it is a two-dimensional hexagonal structure.

  Furthermore, when the X-ray diffraction (XRD) pattern was measured in the same manner for the mesoporous materials obtained in Comparative Examples 2-3, there was also a diffraction peak in the mesoporous materials obtained in Comparative Examples 2-3, The material was confirmed to have a periodic structure. Moreover, it is guessed from the indexing that it is a two-dimensional hexagonal structure.

(Measurement of isothermal adsorption of nitrogen)
For the mesoporous materials obtained in Examples 1 and 2 and Comparative Example 1, isothermal adsorption measurement of nitrogen was performed at 77K using a fully automatic gas adsorption amount measuring device (manufactured by Yuasa Ionics: Autosorb 1-AG). . The obtained isothermal adsorption curve of nitrogen is shown in FIG.

The isotherm during adsorption and desorption was on the same curve in any mesoporous material, and no hysteresis was observed. From this, it was confirmed that reversible physical adsorption occurred. Further, any of the P / P ₀ even in the mesoporous material has shown a rising characteristic rapid adsorption to mesopores of about 0.3, it was confirmed that a good silica-based mesoporous .

(Specific surface area)
About the mesoporous material obtained in Examples 1 and 2 and Comparative Example 1, when the specific surface area was determined by the BET (Brunauer-Emmett-Teller) method, it was about 500 to 750 m ² / g in any mesoporous material. there were.

(Pore size distribution)
About the mesoporous material obtained in Examples 1-2, the pore distribution curve was calculated | required from the adsorption curve using BJH (Barrett-Joyner-Halenda) method based on the Kelvin formula. The pore size distributions of the mesoporous materials obtained in Example 1 and Example 2 are shown in FIGS. 5 (a) and 5 (b), respectively. From the results shown in FIGS. 5 (a) and 5 (b), it was confirmed that the pore diameters of the mesoporous materials obtained in Examples 1-2 were aligned around 2 nm.

(Light irradiation adsorption test on the amount of benzene adsorbed)
A halogen adsorption light source (HOYASHOT HL100E) and a cold light guide for light irradiation (manufactured by Suruga Seiki Co., Ltd .: VFGS) were attached to the vapor adsorption measuring apparatus (BELSORP-18 manufactured by Nippon Bell Co.) shown in FIG. And the light irradiation adsorption test regarding the adsorption amount of benzene shown below was conducted using the mesoporous material obtained in Comparative Example 1. In addition, 10 mg of mesoporous material 1 is disposed inside a glass processing container 2 having a capacity of 17 mL, and centered on visible light having a wavelength of 380 to 780 nm with a maximum irradiation power of 390 mW (guide outlet) from the cold light 3. The irradiated light L was irradiated to the mesoporous material 1. Moreover, the light irradiation part 31 of the processing container 2 and the cold light 3 is arrange | positioned inside the 25 degreeC constant temperature water tank (light-shielding container) 4 made from stainless steel, and 43 mL of glass is provided in the processing container 2 via the valve 10. A preparatory chamber (pipe) 11 is connected. Further, a container 14 in which benzene 13 is stored inside through a valve 12, a pump 16 and a pressure gauge 17 are connected through the valve 15 to the preliminary chamber 11.

  First, after the entire system was sufficiently deaerated, benzene vapor having a predetermined initial pressure (pressure: 9 Torr) was introduced into the preliminary chamber 11. Subsequently, after closing the valve 12 and the valve 15, the valve 10 is opened and benzene vapor is introduced into the processing container 2 until the adsorption amount of benzene on the mesoporous material 1 reaches an equilibrium state without irradiating the light L. I left it alone. Next, the irradiation of the light L was started when the adsorption amount of benzene reached a sufficient equilibrium state, and the irradiation of the light L was stopped after a predetermined time, and the pressure change in the processing container 2 during that time was measured.

  The result when the mesoporous material obtained in Examples 1 and 2 is used, that is, the state of the pressure change that changes due to light irradiation is schematically shown in FIG. Regardless of which mesoporous material is used, when light irradiation is started after reaching the equilibrium state, the pressure increases as shown in FIG. 7, and the increase stops after about 30 seconds to 1 minute. The pressure at was constant (FIG. 7: ON state). Next, when the light irradiation was stopped, the pressure began to decrease again, and again returned to the initial equilibrium state in about 30 seconds to 1 minute (FIG. 7: OFF state). This phenomenon was reproduced in the same way even if the light irradiation was repeatedly started and stopped (desorbed once and then performed again). The increase in pressure is caused by the release of benzene adsorbed inside the mesoporous material. On the other hand, when light irradiation is stopped, the original equilibrium state is restored. Indicates that Since such a phenomenon occurred, it was confirmed that the adsorption characteristics of the mesoporous material were reversibly changed by light irradiation, and adsorption / desorption could be actively controlled by light irradiation.

  Such a phenomenon was observed in the mesoporous material obtained in Examples 1 and 2, but was not observed in the mesoporous material obtained in Comparative Example 1. Therefore, light absorption by the dye was observed in this phenomenon. Has been confirmed to play an important role.

  Next, using the mesoporous material obtained in Examples 1 and 2, a light irradiation adsorption test was performed in a state where the initial equilibrium pressures were different. The initial equilibrium pressure is set to the following three patterns: (i) the pressure at the rising portion of the first adsorption amount on the adsorption isotherm (several Torr), (ii) the adsorption amount with respect to the relative pressure once slightly before the flat amount becomes substantially flat. The test was conducted with the pressure (ten torr) and (iii) the pressure of the flat part (50 to 60 Torr). In addition, the light irradiation power was changed at the same time, and the difference in behavior was also compared. The obtained result is shown in FIG.

  From the comparison of the results shown in FIG. 8, it was confirmed that the mesoporous material obtained in Example 2 had a larger change in the equilibrium state under any conditions. That is, it was confirmed that when the amount of the introduced dye was larger, the amount of change in the adsorption amount due to light irradiation was larger, and the change in the amount of adsorption was larger in proportion to the dye concentration. When the mesoporous material obtained in Example 2 is used, a maximum of about 36% of benzene is released to the outside by light irradiation, and the same amount of benzene is re-introduced again after the light irradiation is stopped. Adsorption was possible.

  In addition, when the dependence on the light irradiation power is compared, the amount of change tends to increase as the power increases, and the dependence is more pronounced in the mesoporous material obtained in Example 2. confirmed.

  The difference due to the difference between the initial equilibrium pressure of several Torr and tens of Torr was not confirmed in any of the mesoporous materials obtained in Examples 1 and 2, but the initial equilibrium pressure was 50 to 60 Torr. On the contrary, the amount of change decreased in any mesoporous material.

  Further, when the valve 10 was opened and benzene vapor was introduced into the processing container 2, the pressure change until the adsorption amount of benzene to the mesoporous material 1 was in an equilibrium state with the light L irradiated was measured. When the initial pressure in the preparatory chamber 11 was 35 Torr or less, it was confirmed that the adsorption rate in the light irradiation state was faster than the light irradiation stopped state until reaching the equilibrium state. On the other hand, when the initial pressure in the preliminary chamber 11 was about 90 Torr, which was close to the saturated vapor pressure (95.1 Torr @ 25 ° C.), no difference was observed in the adsorption rate.

(Comparative Example 5)
A mesoporous material for comparison (organic-inorganic hybrid silica meso having benzene in a silica skeleton) by the same production method as Synthesis Example 1 [Preparation of porous particles] described in JP-A-2002-062477 Porous body) was obtained. When the obtained mesoporous material was subjected to a light irradiation adsorption test on the amount of benzene adsorbed in the same manner as described above, no change in the amount of adsorption due to light irradiation was confirmed.

  As described above, according to the method for producing a dye-containing mesoporous material of the present invention, it is possible to produce a mesoporous material in which a sufficient amount of dye is uniformly incorporated in the skeleton. According to the dye-containing mesoporous material obtained by the production method of the present invention, the adsorption amount of the substance adsorbed on the mesoporous material is reversibly and actively changed by a versatile technique of light irradiation. It becomes possible to make it.

  In addition, the dye-containing mesoporous material obtained by the production method of the present invention uses a so-called functional dye as a dye, so that it can be used for devices, optical recording materials, sensors, and the like that utilize changes in optical characteristics, and can utilize light emission characteristics. In addition, it is useful for applications such as displays and light amplification materials, and is also effective for use in fields where such light functions and catalytic functions are combined.

  In particular, by using an azo dye as the dye in the dye-containing mesoporous material obtained by the production method of the present invention, the function of the azo dye is enhanced by the mesoporous material, improving the light deformability and increasing the density of the light fixability. Etc. are possible.

FIG. 1A and FIG. 1B are graphs showing the infrared absorption spectra of the mesoporous materials obtained in Example 1 and Example 2, respectively. 2 (a), 2 (b) and 2 (c) are graphs showing X-ray diffraction patterns of the mesoporous materials obtained in Comparative Example 1, Example 1 and Example 2, respectively. It is a graph which shows the X-ray-diffraction pattern of the mesoporous body obtained by the comparative example 1, Example 3, and Example 4. FIG. It is a graph which shows the isothermal adsorption curve of nitrogen of the mesoporous material obtained in Examples 1-2 and Comparative Example 1. FIGS. 5A and 5B are graphs showing the pore size distribution of the mesoporous material obtained in Example 1 and Example 2, respectively. It is a schematic diagram which shows the structure of the vapor | steam adsorption measuring apparatus used for the light irradiation adsorption test regarding the adsorption amount of benzene. It is a schematic graph which shows the mode of the pressure change which changes with light irradiation at the time of using the mesoporous material obtained in Examples 1-2. It is a graph which shows the result of the light irradiation adsorption test regarding the adsorption amount of benzene using the mesoporous material obtained in Examples 1-2.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Mesoporous body, 2 ... Glass processing container, 3 ... Cold light, 31 ... Light irradiation part, 4 ... Constant temperature water tank (light-shielding container), 10 ... Valve, 11 ... Glass preliminary chamber (pipe), 12 ... Valve , 13 ... benzene, 14 ... container, 15 ... valve, 16 ... pump, 17 ... pressure gauge, L ... irradiation light.

Claims (4)

A first step of forming an alkoxysilane oligomer by subjecting the conjugate and the alkoxysilane to a condensation reaction in an acidic solution containing the alkoxysilane- dye conjugate and the alkoxysilane ;
In an alkaline solution containing said alkoxysilane oligomer and a surfactant, silica containing a dye allowed condensation reaction of the alkoxysilane oligomer together with the surfactant in the alkoxysilane oligomer allowed to form the introduced complex A second step of obtaining a porous mesoporous material ,
Only including,
The solvent of the acidic solution is a mixed solvent of water and an organic solvent;
The content of the organic solvent in the mixed solvent is 5 to 50% by weight,
The pH value of the solvent of the acidic solution is 6 or less,
The molar ratio of the conjugate to the alkoxysilane in the acidic solution (conjugate: alkoxysilane) is 1:30 to 1: 2.
The pH value of the solvent of the alkaline solution is 8 or more,
The concentration of the surfactant in the alkaline solution is 0.05 to 1 mol / L, and
The content of the alkoxysilane oligomer in the alkaline solution is 0.0055 to 0.33 mol / L in terms of metal concentration,
A method for producing a dye-containing mesoporous material characterized by the following. Method for manufacturing a dye-containing mesoporous material of claim 1, wherein the alkoxysilane is tetraalkoxysilane.   The method for producing a dye-containing mesoporous material according to claim 1 or 2, further comprising a third step of removing the surfactant contained in the dye-containing mesoporous material. The content of all alkoxysilanes in the acidic solution in the first step (total amount of alkoxysilanes and alkoxysilanes in the conjugate) is 0.0055 to 0.33 mol / L in terms of metal concentration. The manufacturing method of the pigment | dye containing mesoporous material as described in any one of Claims 1-3 characterized by the above-mentioned.

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