WO2005031338A1

WO2005031338A1 - Composite member

Info

Publication number: WO2005031338A1
Application number: PCT/JP2004/014429
Authority: WO
Inventors: Kazuki Nakanishi; Shigeru Hanzawa; Yousuke Sato
Original assignee: Ngk Insulators, Ltd.
Priority date: 2003-09-25
Filing date: 2004-09-24
Publication date: 2005-04-07

Abstract

A composite member, which has a holding member having an interstice of a width of 1 mm or less and an inorganic porous material formed in the interstice by a sol-gel transition accompanied by a phase transition, characterized in that the inner wall surface of the holding member, which faces the interstice, has a centerline average surface roughness (Ra) of 0.05 μm or greater. The composite member is reduced in the exfoliation or fallout of the porous material from the inner wall surface.

Description

Specification

Composite members

Technical field to which the invention belongs

The present invention relates to a composite member provided with an inorganic porous material, which is generated by a sol-gel transition accompanied by a phase transition.

Background art

In Japanese Patent Application Laid-Open No. H11-292925, for example, a three-dimensional network having an average diameter of 100 nm or more is formed by a sol-gel method in a gap of 1 mm or less of a chromatographic column. It discloses generating a continuous porous silica material. In this way, we are trying to provide a capillary column for chromatogram that shows high resolution.

Japanese Patent Application Laid-Open No. 2004-1151547 includes a porous skeleton of an inorganic material provided with open pores and dispersed particles exposed on a wall surface facing the open pores of the porous skeleton. An inorganic porous body in which a porous skeleton is formed by a sol-gel transition accompanied by a phase transition is disclosed. Disclosure of the invention

The present inventor has studied production of such a column. However, during actual production, if a porous silica is generated by the sol-gel transition reaction in the gap between the columns, the porous body easily separates from the inner wall surface of the gap between the columns and falls off to the outside of the column There was something. If the porous body falls off in this way, it causes a decrease in yield.

An object of the present invention is to provide a holding member in which a gap having a width of 1 mm or less is formed, and a composite member including an inorganic porous material generated by a sol-gel transition accompanied by a phase transition in the gap. Separation or falling off of the porous material from the inner wall surface when the porous material is generated by the sol-gel transition It is to reduce.

The first invention includes a holding member having a gap of 1 mm or less in width, and an inorganic porous material generated by a sol-gel transition accompanied by a phase transition in the gap. A composite member according to the present invention, characterized in that the center line average surface roughness Ra of the facing inner wall surface is 0.05 / m or more.

According to a second aspect of the present invention, there is provided a holding member having a gap having a width of 1 mm or less, and an inorganic porous material in the gap, wherein the inorganic porous material is an inorganic material having an open pore. And a dispersed particle exposed on a wall surface facing the open pores of the porous skeleton. The porous skeleton is generated by a sol-gel transition accompanied by a phase transition, and a gap between the holding members is formed. A center line average surface roughness Ra of the inner wall surface facing the metal member is 0.05 m or more.

The present inventor has found that when a porous material is generated in a minute gap by a sol-gel transition, the roughness of the inner wall face facing the gap reduces the separation of the porous material from the inner wall and the dropout from the gap. And found it important. That is, by setting the center line average surface roughness Ra of the inner wall surface facing the gap of the holding member to 0.05 μm or more, peeling of the porous material from the inner wall surface and dropping from the gap are reduced. The inventors have found that this is possible and arrived at the present invention. Since it is difficult to increase Ra of the inner wall surface facing the gap of the holding member to a certain degree or more, Ra is usually 20 / m or less, particularly preferably 10 m or less.

To measure the Ra of the inner wall surface facing the gap of the holding member, cut the holding member to expose the inner wall surface facing the gap. Then, Ra of the inner wall surface is measured by a surface roughness meter.

These and other objects, features and advantages of the present invention are set forth in the following Detailed Description of the Invention. The detailed description will become clearer, and a person skilled in the art can make appropriate changes, variations, and modifications. Brief Description of Drawings

FIG. 1 shows a photograph (magnification: 200 times) before forming a porous material in Example 1 of the present invention.

FIG. 2 shows a photograph (magnification: 1000) of the inner wall surface of the composite member of Example 1 after the porous material was peeled off from the inner wall surface of the holding member.

FIG. 3 shows a photograph (magnification: 200 times) before forming a porous material in Example 2 of the present invention.

FIG. 4 shows a photograph (magnification: 1000) of the inner wall surface of the composite member of Example 2 after the porous material was peeled off.

FIG. 5 shows a photograph (magnification: 200 times) of Comparative Example 1 before the porous material was formed.

FIG. 6 shows a photograph (magnification: 1000) of the inner wall surface after the porous material was peeled off from the composite member of Comparative Example 1. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in more detail.

(Holding member)

The holding member used in the first invention and the second invention will be described. The form of the holding member is not particularly limited. The holding member may be a capillary, may be a plurality of flat plates, or may be a honeycomb structure. Also, a plurality of capillaries can be bundled.

The material of the holding member is not particularly limited, and may be a ceramic, a polymer, a metal, a glass, or a ceramics-metal composite material. For example, the following materials Particularly preferred. Inorganic oxides such as silicon oxide, aluminum oxide, titanium oxide, zirconium oxide, and cordierite, and ceramics such as silicon carbide and silicon nitride are preferable.

The holding member may be made of a material whose surface has been treated in order to adjust the adhesiveness with the porous silica formed inside the gap. Examples of methods for treating the surface include a sol-gel method, a chemical vapor deposition method, a physical vapor deposition method, a sputtering method, a plating method, and various other methods.

The method of increasing the Ra of the inner wall surface facing the gap of the holding member is not particularly limited. For example, Ra of the inner wall surface can be increased by increasing the porosity of the material constituting the holding member. Further, the slurry containing the ceramic particles is caused to flow into the gap between the holding members, and the slurry is hardened by heat treatment, so that Ra on the inner wall surface facing the gap can be increased. In the case of ceramics, the inner wall surface Ra can be increased by preparing the holding member from a material having a large particle diameter.

(Inorganic porous material in the first invention)

In the first invention, a porous material generated by a sol-gel transition accompanied by a phase transition exists in a gap between the holding members. In order to cause this formation reaction, a solution containing a precursor of the network-forming component is produced, and a sol is formed by reacting the precursor in the solution (for example, a hydrolysis reaction). (Solidification). This is called the sol-gel transition. At the time of this sol-gel transition, phase separation occurs between a phase rich in a network-forming component causing gel formation (gel phase) and a phase rich in a solvent component not causing gel formation (solvent phase). As a result, since this gel forms a network structure, a porous body having open pores can be obtained by drying the solvent phase and removing the solvent. '' In this sol-gel reaction system, gel formation occurs over time. Phase separation occurs between a phase rich in the scraping network-forming component (gel phase) and a phase rich in the solvent component that does not cause gel formation (solvent phase). In forming each phase region, the diffusion of each component against the concentration gradient occurs using the difference in the chemical potential as a driving force, and each phase region becomes an equilibrium composition under a given temperature and pressure. Mass transfer will continue until it is reached.

When the sol-gel transition reaction is completed in a solvent, the wet gel is washed or subjected to a solvent replacement treatment, and then the solvent is removed to obtain an inorganic porous composite. If necessary, the inorganic porous composite can be heat-treated at an appropriate temperature.

For example, in the case of a chromatography column, the pressure loss is small because the porous body has pores whose pore size and volume ratio are appropriately controlled. In addition, the distribution of the analyte between the solution and the inner surface of the column does not vary from place to place because the fluid channel shape is highly uniform in size.

The pore diameter of the open pores of the porous material is preferably 100 nm or more in diameter. Such macropores are formed as regions occupied by the solvent phase generated during phase separation. When the solvent phase and the gel phase are entangled with each other to form a continuous so-called interconnected structure, an extremely sharp size distribution can be obtained.

The inorganic substance constituting the porous material is not particularly limited. However, metal oxides are particularly preferred. Examples of the metal oxide include silicon oxide, titanium oxide, zirconium oxide, and alumina. Two or more metal oxides may be used.

Examples of the precursor of the network-forming component that causes gel formation used in the sol-gel reaction include the following.

(1) Metal alkoxides, metal complexes, metal salts, organically modified metal alkoxides, organic crosslinked metal alkoxides, alkyl-substituted organometallic alkoxides (2) Partial hydrolysis products of metal alkoxides, metal complexes, metal salts, organically modified metal alkoxides, organic crosslinked metal alkoxides, or alkyl group-substituted organometallic alkoxides

(3) Multimers that are partial polymerization products of metal alkoxides, metal complexes, metal salts, organically modified metal alkoxides, organic cross-linked metal alkoxides or alkyl-substituted organic metal alkoxides

(4) Sol-gel transition by changing pH of water glass and silicate aqueous solution

In a more specific production method, a water-soluble polymer is dissolved in an acidic aqueous solution, and the precursor (particularly preferably a metal compound having a hydrolyzable functional group) is added to carry out a hydrolysis reaction. The degree of polymerization of the precursor of the network forming component gradually increases, and the compatibility with the solvent phase mainly composed of water or the solvent phase mainly composed of the water-soluble polymer decreases. At this time, spinodal decomposition occurs in the solution, and at the same time, gelation occurs due to hydrolysis and polymerization of the network-forming component. The product is then dried and heated.

(Inorganic porous material in the second invention)

In this porous body, each dispersed particle is exposed from the open pore wall surface of the porous body. At this time, preferably, 1 vol.% Or more, more preferably 5 vol.% Or more of the volume of each dispersed particle is raised from the wall surface of the open pores of the porous skeleton. In this inorganic porous material, the porous skeleton is formed by a sol-gel transition accompanied by a phase transition. In order to cause this reaction, a solution containing a precursor of the network-forming component is produced, and the precursor is reacted in the solution, for example, a hydrolysis reaction is performed to form a sol, and the sol is gelled ( Solidification). This is called a sol-gel transition. At the time of this sol-gel transition, phase separation occurs between a phase rich in a network-forming component causing gel formation (gel phase) and a phase rich in a solvent component not causing gel formation (solvent phase). As a result, since this gel has a network structure, the solvent phase is dried to remove the solvent, whereby a porous body having open pores is obtained. After obtaining the porous body, a slurry containing dispersed particles is filled from the open pores of the porous body, and then the porous body is subjected to a heat treatment so that the dispersed particles are exposed in the open pores of the porous body. Is also possible.

However, in a preferred embodiment, dispersed particles coexist in the sol-gel reaction solution in advance. After the sol-gel reaction proceeds, a large number of these dispersed particles are exposed on the wall surface of the open pores of the network structure. In this case, the dispersed particles can be more uniformly dispersed on the walls of the open pores of the porous body.

In a preferred embodiment, dispersed particles are allowed to coexist in a sol-gel reaction solution, and a sol-gel transition accompanied by a phase transition is caused to form a porous skeleton including open pores. To disperse the dispersed particles.

In this sol-gel reaction system, as time elapses, phase separation into a phase rich in a network-forming component causing gel formation (gel phase) and a phase rich in a solvent component not causing gel formation (solvent phase) is performed. Happens. In forming each phase region, diffusion of each component against the concentration gradient occurs by using the difference in chemical potential as a driving force, and each phase region reaches an equilibrium composition at a given temperature and pressure. Until the mass transfer continues. At this time, conditions are selected so that the dispersed particles coexist in the starting composition and that the dispersed particles do not significantly affect the phase separation-sol-gel reaction.

A specific production method will be exemplified.

(1) Add dispersed particles to a solvent, disperse by stirring and sonication. Next, the precursor of the network-forming component is dissolved in the solvent to cause a reaction for generating the network-forming component, and the sol-gel transition and the phase separation reaction proceed. Let

(2) Dissolve the network-forming component in the solvent. The dispersion of the dispersed particles is added to this solution, followed by stirring and ultrasonic treatment. Then, a formation reaction of a network-forming component is caused, and a sol-gel transition and a phase separation reaction proceed.

After the step (1) or (2), the wet gel is washed or subjected to a solvent replacement treatment, and then the solvent is removed to obtain an inorganic porous composite. If necessary, the inorganic porous composite can be heat-treated at an appropriate temperature.

The pore diameter of the open pores of the porous skeleton is preferably 100 nm or more, more preferably 200 nm or more, from the viewpoint of improving the air permeability of the open pores. Such macropores are formed as regions occupied by the solvent phase generated during phase separation. When the solvent phase and the gel phase are entangled with each other to form a continuous so-called interconnected structure,

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Size distribution can be obtained.

There is no particular upper limit on the pore diameter (diameter) of the open pores. However, from the viewpoint of easiness of manufacture, it is preferably at most 1000 nm.

The inorganic substance constituting the porous skeleton is not particularly limited. However, metal oxides are particularly preferred. Examples of the metal oxide include silicon oxide, titanium oxide, zirconium oxide, and alumina. Two or more metal oxides may be used.

Currently, industrially produced and commercially available dispersed particles are mainly composed of organic polymers, metal oxides or metals, and their particle diameters (average diameter) are extremely wide from about 5 nm to about 100 m. Range. It is known that the chemical affinity between these fine particles and the network-forming component causing gel formation can be freely controlled in many cases by chemical modification of the particle surface. Therefore, particles that meet the conditions that do not cause aggregation or sedimentation during the sol-gel reaction Then, it can be applied to the present production method regardless of the chemical composition. Therefore, in the present invention, as the dispersed particles, metal oxides, metals, organic polymers, and composites thereof can be used. Specifically, silicon oxide, titanium oxide, zirconium oxide, aluminum oxide, calcium oxide, magnesium oxide, iron oxide, transition metal oxides, lithium oxide, lanthanum oxide, rare earth oxides, and the like are preferable. . Further, carbonates, nitrates, sulfates, phosphates, halides, inorganic salts, and the like that are stable in the reaction solution can also be used. Organic salts, complexes, protected metal colloids, polymer latexes, and even finely divided organic polymers can be used to produce the inorganic porous composite of the present invention by controlling the dispersibility in the reaction solution. Can be.

The average diameter of the dispersed particles is not particularly limited. Since the dispersed particles must be sized to fit within the open pores of the porous skeleton, the average diameter of the dispersed particles must be smaller than the pore diameter (diameter) of the open pores of the porous skeleton. In particular, from the viewpoint of exerting some function in the open pores, it is preferable that the average diameter of the dispersed particles is somewhat smaller than the diameter of the open pores. From such a viewpoint, the diameter of the dispersed particles is preferably 500 nm or less.

The average diameter of the dispersed particles is preferably 5 nm or more from the viewpoint of suppressing aggregation during dispersion. Also, if the average diameter of the dispersed particles is too small compared to the diameter of the open pores, the fluid passing through the open pores will be less likely to come into contact with the dispersed particles, and the function may not be exerted. . Therefore, if the material on which the present application is based is specified, the diameter D of the open pores of the porous body without the addition of the dispersed particles / the diameter d of the dispersed particles is preferably 600 or less, and 100 or less. Is more preferable.

Also, if the dispersed particles are elongated, the surroundings of the dispersed particles during the phase transition process Changes, and irregular irregularities are likely to occur on the inner wall surface of the open pores. From the viewpoint of preventing this, the average aspect ratio (major axis / minor axis) of the dispersed particles is preferably set to 1.5 or less.

'The weight ratio of the dispersed particles is preferably 90% by weight or less, more preferably 80% by weight or less, based on the whole inorganic porous composite material.

Further, from the viewpoint of exerting the function of the dispersed particles, the weight ratio of the dispersed particles is preferably 0.01% by weight or more based on the whole inorganic porous composite, and more preferably 0.1% by weight. More preferably, it is more than 1% by weight. The effect of supporting the dispersed particles in the open pores is not particularly limited. For example, it may have a surface roughness forming function of increasing the surface roughness of the open pores and increasing the contact area between the fluid and the inner wall surface of the porous skeleton. Further, it may have a catalytic function of a chemical reaction.

(1) Metal alkoxides, metal complexes, metal salts, organically modified metal alkoxides, organic crosslinked metal alkoxides, alkyl-substituted organometallic alkoxides

(2) Partial hydrolysis products of metal alkoxides, metal complexes, metal salts, organically modified metal alkoxides, organic crosslinked metal alkoxides, or alkyl group-substituted organometallic alkoxides

() Sol-gel transition by changing pH of water glass and silicate aqueous solution

In a more specific manufacturing method, a water-soluble polymer is dissolved in an acidic aqueous solution, The dispersion particles are added thereto, and the mixture is dispersed by stirring and ultrasonic treatment. Then, the precursor, particularly preferably a metal compound having a hydrolyzable functional group, is added to carry out a hydrolysis reaction. The precursor of the network-forming component gradually increases its degree of polymerization, and the compatibility with the solvent phase mainly composed of water or the solvent phase mainly composed of the water-soluble polymer decreases. At this time, spinodal decomposition occurs in the solution, and at the same time, gelation occurs due to hydrolysis and polymerization of the network-forming component. The product is then dried and heated.

(Examples of materials for inorganic porous materials in the first and second inventions)

Here, the water-soluble polymer is a water-soluble organic polymer that can be converted into an aqueous solution having an appropriate concentration, and is uniformly dissolved in a reaction system containing an alcohol generated by a metal compound having a hydrolyzable functional group. Anything can be obtained. Specifically, sodium or potassium salts of polystyrene sulfonic acid, which is a polymer metal salt, polyacrylic acid, which is a polymer acid and dissociates to form a polyanion, and a polymer base, which forms a polycation in an aqueous solution. The resulting polyallylamine and polyethyleneimine, or a neutral polymer which is a polyethylene oxide having an ether bond in the main chain, or polyvinylpyrrolidone is preferred. Formamides, polyhydric alcohols and surfactants may be used in place of the organic polymer, in which case glycerin is the best polyhydric alcohol and polyoxyethylene alkyl ethers are the best surfactants. It is.

As the metal compound having a hydrolyzable functional group, a metal alkoxide or an oligomer thereof can be used. For example, those having a small number of carbon atoms such as a methoxy group, an ethoxy group, and a propoxy group are preferable. . As the metal, a metal of an oxide to be finally formed, for example, Si, Ti, Zr, or A1 is used. The metal may be one kind or two or more kinds. On the other hand, as Oligomer Any substance that has been dissolved and dispersed may be used, and specifically, up to about 10-mers can be used. Alkoxyalkoxysilanes, in which some of the alkoxy groups of these silicon alkoxides are substituted with alkyl groups, and oligomers up to about 10-mers thereof are preferably used. Alkyl-substituted metal alkoxides in which the central metal element is replaced with titanium, zirconium, aluminum or the like instead of silicon can also be used.

The acidic aqueous solution is preferably one having a mineral acid such as hydrochloric acid or nitric acid of 0.01 N or more, or one having an organic acid such as formic acid or acetic acid of 0.01 N or more.

The hydrolysis and polymerization reaction can be achieved by storing the solution at room temperature of 40 to 80 ° C for 0.5 to 5 hours. During this process, gelation and phase separation proceed.

The porous material of the present invention can carry an enzyme such as glucose isomerase, a catalyst such as platinum and palladium, and a functional group such as an octadecyl group. The composite member of the present invention can be suitably used, for example, for a column for chromatography in liquid chromatography.

Example

[Example 1]

A honeycomb substrate having an interplanar spacing of 1.0 mm, a porosity of about 60%, and Ra = 5.16 μm was prepared. FIG. 1 shows a photograph (magnification: 200 times) of a porous material on the inner wall surface of the honeycomb substrate before a porous material was generated. Fine irregularities can be seen on the inner wall.

(Formation of porous material in the gap between honeycomb substrates)

0.9 g of polyethylene oxide (manufactured by Aldrich), which is a water-soluble polymer, was dissolved in 10 ml of a 0.01 mol / L acetic acid aqueous solution and uniformly dissolved to obtain a solution. Then, after stirring for 10 minutes under ice-cooling, tetramethoxysilane (net 5 ml of an eye-forming component precursor (Shin-Etsu Silicone) was added under stirring to carry out a hydrolysis reaction. The resulting clear solution was injected into each gap. When the honeycomb substrate was kept in a constant temperature bath at 40 ° C, the transparent solution solidified. Next, the composite member of the present invention was obtained by aging at 40 ° C. for about 24 hours and then drying at 60 ° C.

The obtained composite member was cut, and the porous material was peeled off. Next, FIG. 2 shows a photograph (magnification: 10000) of the inner wall surface after the porous material was peeled off. In FIG. 2, the white protrusions are a porous silica material. That is, it was confirmed that the porous material remained on the inner wall surface of the void after the silica porous material was forcibly peeled off from the inner wall surface. This indicates that the porous material was caught on the inner wall surface of the void and was strongly held by the honeycomb substrate.

[Example 2]

A composite member was produced in the same manner as in Example 1. However, the interplanar spacing of the gaps of the honeycomb substrate was 0.95 mm. The Ra of the inner wall surface facing the pores of the honeycomb substrate was 1.74 m. The porosity of the honeycomb substrate was about 30%. FIG. 3 shows a photograph (magnification: 20.0 times) before the porous material was formed on the inner wall surface of the honeycomb substrate. Fine irregularities can be seen on the inner wall.

A porous silica material was generated in each hole of the honeycomb substrate in the same manner as in Example 1 to produce a composite member of the present invention.

The obtained composite member was cut, and the porous material was peeled off. Next, FIG. 4 shows a photograph (magnification: 10000) of the inner wall surface after the porous material was peeled off. In FIG. 4, the white protrusions are a porous silica material. That is, it was confirmed that the porous material remained on the inner wall surface of the void after the silica porous material was forcibly peeled off from the inner wall surface. This is because the porous material This indicates that the sheet is caught on the inner wall surface and is strongly held by the honeycomb substrate.

[Example 3]

Alumina powder (manufactured by Sumitomo Chemical Co., Ltd., trade name: AES-11C) is pelletized by adding a binder, a dispersing agent, and water. A square plate with a height of 40 mm and a thickness of 4 mm was formed. The square plate was dried and fired at 1600 ° C. to obtain an alumina square plate. A gap of about 1.0 mm was formed between the square plates. The Ra of the inner wall surface facing the hole of the square plate was 0.06997Π1. Before the porous material is formed on the inner wall surface of this alumina square plate, fine irregularities can be confirmed on the inner wall surface in the same manner as in Examples 1 and 2. A porous silica material was generated in the gaps of the alumina square plate in the same manner as in Example 1 to produce a composite member of Example 3.

The obtained composite member was cut, and the porous material was peeled off. Next, when the inner wall surface after peeling the porous material was observed, it was confirmed that the porous material remained on the inner wall surface of the void, almost in the same manner as in Examples 1 and 2. This indicates that the porous material was caught on the inner wall surface of the void and was strongly held by the honeycomb substrate.

[Comparative Example 1]

A pair of dense slide glasses was prepared, and a gap of 1.0 mm was formed between the slide glasses. The Ra of the inner wall surface facing the pores of the slide glass was 0.0607 m. Figure 5 shows a photograph (magnification: 200x) of the inner surface of the slide glass before the porous material was formed. The inner wall surface is almost flat.

A porous silica material was generated in the gap between the slide glasses in the same manner as in Example 1 to produce a composite member of the comparative example. The obtained composite member was cut, and the porous material was peeled off. Next, FIG. 6 shows a photograph (magnification: 1000) of the inner wall surface after the porous material was peeled off. As shown in Fig. 6, a small amount of white porous silica material is seen on the surface of the slide glass. However, this silica only rests on the slide glass, and is not caught and held on the slide glass surface.

As described above, according to the present invention, a holding member having a gap having a width of 1 mm or less and an inorganic porous material generated by a sol-gel transition accompanied by a phase transition are provided in the gap. In such a composite member, when the porous material is generated by the sol-gel transition in the gap, peeling or falling off of the porous material from the inner wall surface can be reduced.

[Example 4]

A honeycomb having a cell pitch of 1.04 mm, a wall thickness of 0.09 mm, a spacing of 0.95 mm, and a porosity of about 30% for the wall was prepared. This honeycomb was cut, and Ra on the inner wall surface was measured with a surface roughness meter. As a result, Ra was 1.7 / m. Observation of this honeycomb with an electron microscope revealed fine irregularities on the inner wall and pores of several meters in diameter.

22.5 g of polyethylene oxide, a water-soluble polymer, was dissolved in 300 ml of a 0.01 mol / L acetic acid aqueous solution, and uniformly dissolved to obtain an aqueous solution. To this solution was added 3.0 g of silica particles (“SO-C2” manufactured by Admatech), and after stirring for 5 minutes, ultrasonic waves were further applied for 5 minutes to disperse the silica particles. Then, after stirring for 10 minutes under ice-cooling, 120 ml of tetramethoxysilane was added with stirring, and the mixture was stirred for 60 minutes under ice-cooling. The honeycomb (surface gap 0.95 mm _N Ra = 1.7 m) is immersed in the obtained solution, and the reaction solution is shaken to remove air bubbles in the cell. Then, the container containing the honeycomb and the reaction solution is sealed. After standing in a constant temperature bath at 40 ° C, the reaction solution solidified. Then, as it is After aging for 24 hours, it was taken out of the closed container, and the porous silica adhered to the outer surface of the honeycomb was removed. Then, the honeycomb was dried at 60 ° C to obtain a composite member of the present invention.

After extruding and forcibly exfoliating the porous porous body formed inside the cell of the obtained composite member, the honeycomb is cut, and the inner wall surface of the honeycomb supporting the porous silica body is observed with an electron microscope. Upon observation, it was confirmed that the porous silica containing dispersed particles remained in the concave portions and pores of the honeycomb wall surface. This indicates that the porous silica containing the dispersed particles caught on the inner wall surface of the honeycomb cell and was strongly held by the honeycomb.

[Example 5]

Alumina powder (AES-11C, manufactured by Sumitomo Chemical Co., Ltd.) is pelletized by adding a binder, a dispersant, and water, and is 40 mm long, 40 mm high and 40 mm thick with a 30-ton electric injection molding machine. A 4 mm square plate was formed. The square plate was dried and fired at 1600 ° C. to obtain a sintered body of an alumina square plate. The R _a of the square plate was measured by a surface roughness meter was Ra = 0.070 z ni. Observation of the surface of the alumina square plate with an electron microscope confirmed fine irregularities seen as grain boundaries of the alumina powder. A pair of alumina square plates having a gap of l.Oimn was prepared by sandwiching a 1.0 mm spacer between both ends of the two square plates. 1.8 g of polyethylene oxide, which is a water-soluble polymer, was dissolved in 20 ml of an aqueous solution of O.Olmol / L acetic acid and uniformly dissolved to obtain an aqueous solution. To this solution, 0.2 g of silica force particles (“S0-C1” manufactured by Admatech) was added, and after stirring for 5 minutes, ultrasonic waves were further applied for 5 minutes to disperse the silica particles. Thereafter, the mixture was stirred for 10 minutes under ice cooling, and then 8 ml of tetramethoxysilane was added thereto with stirring, followed by stirring for 60 minutes under ice cooling. After immersing the above-mentioned alumina square plate pair (surface interval 1.0 mm, Ra = 0.070 m) in the obtained solution, the alumina square plate pair is gently shaken to remove bubbles, and the reaction solution and the alumina square plate pair are separated. Seal the entire container The reaction solution solidified when allowed to stand in a constant temperature bath at 40 ° C. Then, after aging for 24 hours, the closed container was opened to remove the pair of alumina square plates, the porous silica on the outer surface thereof was removed, and dried at 60 ° C to obtain an example of the present invention. Was obtained.

After extruding and forcibly exfoliating the porous silica body formed inside the pair of alumina square plates of the obtained composite member, the spacer was removed from the alumina square plate to sandwich the porous silica body. When the inner wall surface of the alumina square plate was observed with an electron microscope, it was confirmed that a silica porous body containing dispersed particles remained in some of the recesses of the alumina square plate. This indicates that the porous silica containing the dispersed particles caught the inner wall surface of the alumina square plate and was strongly held by the alumina square plate.

[Comparative Example 2]

A dense slide glass was prepared. The Ra of this slide glass was measured with a surface roughness meter, and found to be Ra = 0.0067 ^ 111. When the surface of the slide glass was observed with an electron microscope, the surface was almost flat. A pair of slide glasses having a gap of 1.0 mm was produced by sandwiching a 1.0 mm spacer between both ends of the two slide glasses.

1.5 g of polyethylene oxide, which is a water-soluble polymer, was dissolved in 20 ml of an aqueous solution of acetic acid of 0.01 raol / L and uniformly dissolved to obtain an aqueous solution. To this solution was added 0.2 g of silica particles ("SO-C2" manufactured by Admatech), and after stirring for 5 minutes, ultrasonic waves were further applied for 5 minutes to disperse the silica particles. Then, after stirring for 10 minutes under ice-cooling, 8 ml of tetramethoxysilane was added with stirring, and the mixture was stirred for 60 minutes under ice-cooling. After the above slide glass pair (surface gap: 1.0 mm, Ra = 0.0067 zm) is immersed in the obtained solution, the slide glass pair is gently shaken to remove bubbles, and the reaction solution and the slide glass pair are placed in each container. The reaction solution solidified when left tightly closed and kept in a constant temperature bath at 40 ° C. Then After aging for 24 hours as it is, the closed container is opened to remove the slide glass pair, the porous silica on the outer surface is removed, and dried at 60 ° C to obtain the composite member of the present invention. Got.

After extruding and forcibly exfoliating the porous silica formed inside the slide glass pair of the obtained composite member, the spacer was removed from the slide glass to sandwich the porous silica body. Observation of the inner wall surface with an electron microscope revealed that almost no porous silica containing dispersed particles remained. Only a small amount of the porous silica remained on the slide glass, and it was not observed that the porous silica was retained on the slide glass surface.

Although described with reference to the preferred embodiments of the present invention, the present invention is not limited to these embodiments, and these embodiments are described only for illustrative purposes. Various changes can be made without departing from the scope of the invention.

Claims

The scope of the claims

1. A holding member having a gap having a width of 1 mm or less, and an inorganic porous material generated by a sol-gel transition accompanied by a phase transition in the gap, facing the gap of the holding member. A composite member, characterized in that the center line average surface roughness Ra of the inner wall surface is not less than 0.05 / m.

2. The composite member according to claim 1, wherein the holding member is a honeycomb structure.

3. The composite member according to claim 1, wherein the inorganic porous material is made of silica.

4. A holding member in which a gap having a width of 1 mm or less is formed, and an inorganic porous material is provided in the gap, and the inorganic porous material comprises an inorganic porous skeleton having open pores. And dispersed particles exposed on a wall surface facing the open pores of the porous skeleton, wherein the porous skeleton is generated by a sol-gel transition accompanied by a phase transition, and the gap of the holding member A composite having a center line average surface roughness of the inner wall surface facing the surface;

5. The composite member according to claim 4, wherein the dispersed particles are made of at least one material selected from the group consisting of a metal oxide, a metal, an organic polymer, and a composite thereof. .

6. The composite member according to claim 4, wherein the holding member is a honeycomb structure.

7. The composite member according to any one of claims 4 to 6, wherein the inorganic porous material is made of silica.