JP5041534B2 - A method for manufacturing a honeycomb-shaped porous body. - Google Patents

Description

  The present invention relates to a method for manufacturing a honeycomb-shaped porous body having a fine periodic structure.

  A structure having a fine periodic structure is a useful material in various fields such as electronics, optics, and biotechnology. In the field of electronics, a process for producing an electronic material having a fine periodic structure of 100 nm or less has been put into practical use along with a technique for miniaturizing a channel of an electric field transistor (Non-Patent Document 1). In the field of optics, a structure having a fine periodic structure such as a diffraction grating or a photonic crystal has attracted attention as a next-generation optical functional element (Non-patent Document 2). Further, a thin film having a fine periodic structure having a periodic structure equal to or less than the wavelength of light is transparent in the visible light region, and is expected to have an effect of preventing light scattering and the like. Furthermore, in recent years, in the field of regenerative medicine, it has been reported that the fine structure on the surface of a structure having a fine periodic structure affects the growth of cultured cells (Non-patent Document 3).

  As conventional techniques for producing a structure having a fine periodic structure, photolithography, soft lithography (Non-Patent Document 4), and the like are known. Such a method produces a structure having a fine periodic structure by finely cutting a material as a raw material, and is called a top-down production process. In general, a top-down fabrication process is based on breaking intermolecular bonds, and thus essentially requires high energy. Therefore, this process is an expensive process that requires multi-step processes, and there are many problems to be solved as a method of manufacturing a structure having a simple periodic structure such as a diffraction limit.

  On the other hand, an attempt has been made to produce a structure having a fine periodic structure by stacking materials from the molecular level. For example, phase separation of a block copolymer is known as a process for producing a structure having a 10 nm scale microstructure (Non-patent Document 5). In the block copolymer in which the ends of two or more kinds of polymers having different compatibility are connected by a covalent bond, the period of the phase separation structure can be changed depending on the compatibility and the length of each segment. However, this method also requires a complicated organic synthesis process, and the types of block copolymers that can be synthesized are limited.

  In addition, a method for producing a structure having a two-dimensional and three-dimensional periodic structure by accumulating submicron colloidal fine particles (Non-Patent Document 6), and having an inverted opal structure by using this as a template Although methods for producing structures (Non-Patent Document 7) have been reported, in these methods, fine particles having a single particle size must be prepared, and the mold is disassembled after taking the mold. There are various process problems, such as that that must be done.

As a method based on a principle different from these methods, there has been reported a method for easily producing a structure having a fine honeycomb periodic structure (honeycomb porous body) using water droplets as a mold (Patent Document 1). . Specifically, water droplets are condensed on the surface of a polymer non-aqueous organic solvent solution, and a honeycomb-shaped porous body is prepared using the water droplets as a template.
Gelzinge et al., IEEE Spectrum 1989, 89, 43. Noda et al., Nature, 2000, 407, 608. Chen et al., Science, 1997, 276, 1425 White Size et al., Angew. Chem. Int. Ed. 1998, 37, 550-575. Albrecht et al., Macromolecules, 2002, 35, 8106-8110. Lang et al., Volume 17, pp. 6751-6753. Carso et al., Langmuir, 1999, 15: 8276-8281 Japanese Patent Laid-Open No. 8-311231

  However, in any of the above methods, no attention is paid to the production of a structure having a fine periodic structure with high quality by making the pore diameter of the porous body uniform.

  An object of the present invention is to provide a technique for making the pore diameter of a porous body substantially uniform in a method for manufacturing a honeycomb-shaped porous body that is a structure having a fine periodic structure using water droplets as a mold. It is in.

  In the method for producing a honeycomb-shaped porous body using water droplets as a template, the present inventors have made a porous body by causing a surfactant having a constant interfacial tension to be present in a water-insoluble organic solvent solution of a water-insoluble polymer. The inventors have found that it is possible to produce a high-quality honeycomb porous body by suppressing variation in the pore diameter of the present invention.

  The present invention provides the following manufacturing method.

1) A water-insoluble organic solvent solution in which a water-insoluble polymer and a surfactant are dissolved in a water-insoluble organic solvent and having an interfacial tension with respect to water of 10 to 20 mN / m is applied to a glass or metal substrate. A method for producing a honeycomb-shaped porous body made of a water-insoluble polymer substance, comprising a step of preparing a thin film of a solution and a step of evaporating an organic solvent from the thin film on the substrate.

2) The production method according to 1), wherein the surfactant is one or more surfactants selected from compounds represented by formula (I) or formula (II).

（式中、ｎ：ｍは１：０〜１０：１である）。Formula (I)

(Where n: m is 1: 0 to 10: 1).

（式中、Ｒ_１ならびにＲ_２はそれぞれ独立にＣ_１１〜Ｃ_１７の脂肪族炭化水素基から選ばれ、Ｒ_３はＮ^＋（ＣＨ_３）_３又はＮＨ_３から選ばれる）。Formula (II)

(In the formula, R ₁ and R ₂ are each independently selected from C _{11 to} C ₁₇ aliphatic hydrocarbon groups, and R ₃ is selected from N ⁺ (CH ₃ ) ₃ or NH ₃ ).

3) The surfactant of the formula (I) is poly (dodecylacrylamide-co-6-aminocaproic acrylamide) having a copolymerization ratio = 1: 10 to 10: 1 and a molecular weight = 20,000 to 500,000. ) Manufacturing method.

4) The production method according to 2), wherein the surfactant represented by the formula (II) is dioleyl phosphatidylethanolamine, dipalmitoyl phosphatidylethanolamine, or dimyristoyl phosphatidylcholine.

5) The production method according to 1), wherein the surfactant is one or more surfactants selected from compounds represented by formula (III) or formula (IV).

式（ＩＶ）

（前記式（ＩＩＩ）並びに式（ＩＶ）中、ＲはＲ’又はＲ’Ｏを表し、Ｒ’は水素原子又は４〜２２個の炭素原子を有する脂肪族炭化水素基、ハロゲン、ヒドロキシ基、アルコキシ基又はハロアルコキシ基を表し、Ａは１〜５０個の炭素原子を有する脂肪族の二価基を表し、ｎは０〜６の整数を表し、Ｘは−ＣＯＯＭ、−ＳＯ_３Ｍ、−ＰＯ（ＯＭ）_２又はその塩もしくは水酸基を表し、Ｍは水素原子または塩を形成しうるカチオン若しくはカチオン分子を表し、Ｒ_Ｏは水素原子または炭素数４〜２２個の脂肪族炭化水素基を表わし、式（ＩＩＩ）の化合物は単一モノマーからなるホモポリマー又はモノマー単位でそれぞれ異なる上記Ｒ、Ａ、ｎ及びＸを有するコポリマーでもよく、式（ＩＶ）の化合物は各モノマー単位でそれぞれ同一の又は異なる上記Ｒ、Ａ、ｎ及びＸを有するランダムコポリマーでもよい）
６）界面活性剤が式（Ｖ）で表される化合物から選択される１種以上の界面活性剤である、１）に記載の製造方法。

（前記式（Ｖ）中、Ｒ_４は炭素数が１〜５０の脂肪族炭化水素又は芳香族炭化水素を表し、Ｘは−ＳＯ_３Ｍ、−ＣＯＯＭ又は−ＰＯ（ＯＭ）_２で表される酸性基またはそれらの塩を示し、Ｍは水素原子又は塩を形成しうるカチオン若しくはカチオン分子を表す）
７）相対湿度３０％以上の湿度を有する流速０．１〜１００Ｌ／分の気流下に薄膜を置いて溶媒の蒸発を行う、１）に記載の製造方法。Formula (III)

Formula (IV)

(In the formula (III) and the formula (IV), R represents R ′ or R′O, and R ′ represents a hydrogen atom or an aliphatic hydrocarbon group having 4 to 22 carbon atoms, a halogen, a hydroxy group, Represents an alkoxy group or a haloalkoxy group, A represents an aliphatic divalent group having 1 to 50 carbon atoms, n represents an integer of 0 to 6, X represents —COOM, —SO ₃ M, — PO (OM) ₂ or a salt or hydroxyl group thereof, M represents a hydrogen atom or a cation or cation molecule capable of forming a salt, and R 2 _O represents a hydrogen atom or an aliphatic hydrocarbon group having 4 to 22 carbon atoms. The compound of the formula (III) may be a homopolymer consisting of a single monomer or a copolymer having the above R, A, n and X different in monomer units, and the compound of the formula (IV) may be the same or different in each monomer unit Different Or a random copolymer having the above R, A, n and X)
6) The production method according to 1), wherein the surfactant is one or more surfactants selected from compounds represented by formula (V).

(In the formula (V), R ₄ represents an aliphatic hydrocarbon or aromatic hydrocarbon having 1 to 50 carbon atoms, and X is represented by —SO ₃ M, —COOM, or —PO (OM) _2. An acidic group or a salt thereof, and M represents a hydrogen atom or a cation or a cation molecule capable of forming a salt)
7) The production method according to 1), wherein the solvent is evaporated by placing a thin film in an air flow having a relative humidity of 30% or more and a flow rate of 0.1 to 100 L / min.

8) The production method according to 1) or 7), wherein the thin film is prepared by applying a water-insoluble organic solvent solution to the substrate while moving the substrate in a uniaxial direction.

9) The method according to 1), 7) or 8), wherein a substrate whose surface is modified with an alkylated silane coupling agent is used.

The apparatus which manufactures the honeycomb porous body of the present invention continuously is shown. FIG. 1 shows an overall view of operations and devices in Embodiment 1. FIG. The optical microscope image of the honeycomb porous body of the present invention obtained in Example 1 is shown. The left is a honeycomb-like porous body obtained from the solution (A), and the right is a honeycomb-like porous body obtained from the solution (B). The optical microscope image of the honeycomb-shaped porous body prepared from the solution (C) is shown. The optical microscope image of the honeycomb porous body of the present invention obtained in Example 2 is shown. The optical microscope image of the honeycomb porous body of the present invention obtained in Example 3 is shown. The optical microscope image of the honeycomb porous body of the present invention obtained in Example 4 is shown. The optical microscope image of the honeycomb porous body of the present invention obtained in Example 5 is shown. The bar in the figure is a scale bar (10 μm) The optical microscope image of the honeycomb porous body of the present invention obtained in Example 6 is shown. The lower bar is a scale bar (10 μm).

  According to the method of the present invention, a water-insoluble organic solvent solution having a water-insoluble organic solvent and a surfactant dissolved in a water-insoluble organic solvent and having an interfacial tension with respect to water of 10 to 20 mN / m is obtained from a glass or metal substrate. The present invention relates to a method for manufacturing a honeycomb-shaped porous body made of a water-insoluble polymer substance, which includes a step of applying a thin film on the substrate to prepare a thin film of the solution and a step of evaporating an organic solvent from the thin film on the substrate. In this method, water droplets are condensed on the surface of a polymer non-aqueous organic solvent solution, and a honeycomb porous body is prepared using the water droplets as a template.

  In the present invention, a honeycomb-like porous body (also referred to as a honeycomb structure or a honeycomb sheet) is a porous thin film made of a water-insoluble polymer (polymer) and is oriented in the vertical direction of the film. Submicron-scale or micron-scale minute holes (including dents) are provided in a honeycomb shape (honeycomb shape) in the plane direction of the film. The holes may penetrate the film in the vertical direction, or may communicate with surrounding holes existing in the planar direction inside the film. A porous thin film in which pores are provided in such a regular arrangement such as a honeycomb shape is completely different from a normal porous body having irregular pores in which the pore diameter, shape or depth varies. Understood as a different structure.

  As the shape of the honeycomb-shaped porous body in the present invention, the film thickness is 0.01 μm to 100 μm, preferably 0.1 μm to 50 μm, more preferably 1 μm to 20 μm, and the pore diameter is 0.001 μm to 100 μm, preferably 0. .1 μm to 50 μm, more preferably 1 μm to 20 μm, and particularly preferably 5 μm to 10 μm.

  A honeycomb-shaped porous body having such a structural feature is a method for forming a honeycomb-shaped porous body by condensing water droplets on the surface of a polymer non-aqueous organic solvent solution and using the water droplets as a template, for example, Patent Document 1, JP-A No. 2001-157475, JP-A No. 2002-347107 or JP-A No. 2002-335949.

  One of the steps constituting the production method of the present invention is a water-insoluble organic solvent solution in which a water-insoluble polymer and a surfactant are dissolved in a water-insoluble organic solvent and the interfacial tension with respect to water is 10 to 20 mN / m. This is a step of preparing a thin film of the solution by applying to a glass or metal substrate.

  The water-insoluble organic solvent that can be used in the present invention is water-insoluble enough to retain water droplets condensed on the solvent surface, and has a boiling point of 0 to 150 ° C., preferably 10 to 50 ° C. under atmospheric pressure. Any of them can be used. Specifically, halogenated hydrocarbons such as carbon tetrachloride, dichloromethane and chloroform, aromatic hydrocarbons such as benzene, toluene and xylene, esters such as ethyl acetate and butyl acetate, and water-insoluble such as methyl isobutyl ketone. Examples thereof include ketones and carbon disulfide.

  Among these, it can be appropriately selected and used in consideration of solubility in the polymer to be specifically used (described in the next section).

  The water-insoluble polymer used in the present invention is insoluble in water and soluble in the above water-insoluble organic solvent, or can be dissolved in the same organic solvent in the presence of the surfactant used in the present invention described later. Any polymer can be used, and a polymer that can provide the functions or characteristics expected of the honeycomb porous body to be produced can be appropriately selected and used.

  Examples thereof include biodegradable polymers such as polylactic acid and polyhydroxybutyric acid, aliphatic polycarbonates, amphiphilic polymers, photofunctional polymers, and electronic functional polymers.

  Examples of specific combinations of the water-insoluble organic solvent and the water-insoluble polymer include, for example, polyalkyl methacrylate or polyalkyl acrylate such as polystyrene, polycarbonate, polysulfone, polyethersulfone, polyalkylsiloxane, and polymethyl methacrylate. For a polymer selected from the group consisting of polybutadiene, polyisoprene, poly (N-vinylcarbazole), polylactic acid, poly (ε-caprolactone), polyalkylacrylamide, and copolymers thereof, A combination of organic solvents such as dichloromethane, chloroform, benzene, toluene, xylene, carbon disulfide can be used.

  In the present invention, the water-insoluble polymer may be used dissolved in a water-insoluble organic solvent so as to be 0.01 g / L to 50 g / L, preferably 0.1 g / L to 10 g / L. This polymer concentration can be determined as appropriate according to the properties and physical properties required for the honeycomb-shaped porous body to be produced and the solvent used.

  The surfactant that can be used in the present invention is preferably one or more surfactants selected from compounds represented by formula (I) or formula (II).

（式中、ｎ：ｍは１：０〜１０：１である）。Formula (I)

(Where n: m is 1: 0 to 10: 1).

（式中、Ｒ_１ならびにＲ_２はそれぞれ独立にＣ_１１〜Ｃ_１７の脂肪族炭化水素基から選ばれ、Ｒ_３はＮ^＋（ＣＨ_３）_３又はＮＨ_３から選ばれる）。Formula (II)

(In the formula, R ₁ and R ₂ are each independently selected from C _{11 to} C ₁₇ aliphatic hydrocarbon groups, and R ₃ is selected from N ⁺ (CH ₃ ) ₃ or NH ₃ ).

In the compound of the formula (I), it is preferable to use a compound of n: m = 1: 0, 4: 1 or 10: 1, particularly a copolymerization ratio = 1: 10 to 10: 1 and a molecular weight = 20,000 to 50. Preference is given to using poly (dodecylacrylamide-co-6-aminocaproic acrylamide) (Cap). The compound of formula _{(II), R 1, R} 2 = C 11 H 23, R 3 = N + (CH 3) 3 in which dimyristoyl phosphatidylcholine _{(DMPC), R 1, R} 2 = C 15 Use of dipalmitoylphosphatidylcholine (DPPC) where H ₃₁ , R ₃ = N ⁺ (CH ₃ ) or dioleylphosphatidylethanolamine (DOPE) where R ₁ , R ₂ = C ₁₇ H ₃₃ , R ₃ = NH ₃ preferable.

  These surfactants are all known substances, and can be purchased, for example, from Aldrich, etc., and can also be produced according to the method of Nishida et al. (Polymer Journal, 34, 166, 2002). it can.

  In the present invention, a surfactant represented by formula (III) or formula (IV) can also be used.

式（ＩＶ）

前記式（ＩＩＩ）並びに式（ＩＶ）中、ＲはＲ’又はＲ’Ｏを表し、Ｒ’は水素原子又は４〜２２個の炭素原子を有する脂肪族炭化水素基、ハロゲン、ヒドロキシ基、アルコキシ基又はハロアルコキシ基を表し、Ａは１〜５０個の炭素原子を有する脂肪族の二価基を表し、ｎは０〜６の整数を表し、Ｘは−ＣＯＯＭ、−ＳＯ_３Ｍ、−ＰＯ（ＯＭ）_２又はその塩もしくは水酸基を表し、Ｍは水素原子または塩を形成しうるカチオン若しくはカチオン分子を表し、Ｒ_Ｏは水素原子または炭素数４〜２２個の脂肪族炭化水素基を表わし、式（ＩＩＩ）の化合物は単一モノマーからなるホモポリマー又はモノマー単位でそれぞれ異なる上記Ｒ、Ａ、ｎ及びＸを有するコポリマーでもよく、式（ＩＶ）の化合物は各モノマー単位でそれぞれ同一の又は異なる上記Ｒ、Ａ、ｎ及びＸを有するランダムコポリマーでもよい。Formula (III)

Formula (IV)

In the formula (III) and the formula (IV), R represents R ′ or R′O, and R ′ represents a hydrogen atom or an aliphatic hydrocarbon group having 4 to 22 carbon atoms, halogen, hydroxy group, alkoxy. A group or a haloalkoxy group, A represents an aliphatic divalent group having 1 to 50 carbon atoms, n represents an integer of 0 to 6, and X represents —COOM, —SO ₃ M, —PO (OM) ₂ or a salt thereof or a hydroxyl group thereof, M represents a hydrogen atom or a cation or a cation molecule capable of forming a salt, R 2 _O represents a hydrogen atom or an aliphatic hydrocarbon group having 4 to 22 carbon atoms, The compound of the formula (III) may be a homopolymer consisting of a single monomer or a copolymer having the above R, A, n and X different in monomer units, and the compound of the formula (IV) may be the same or different in each monomer unit. Or a random copolymer having the above R, A, n and X.

  The aliphatic hydrocarbon group having 4 to 22 carbon atoms represented by R ′ may be linear or branched, and may have an unsaturated bond, and the aliphatic hydrocarbon group. Two or more kinds of groups may be mixed.

  The number of carbon atoms of the aliphatic hydrocarbon group represented by R ′ is preferably 6 to 18. Examples thereof include alkyl groups such as butyl, amyl, hexyl, octyl, nonyl, dodecyl, and octadecyl, and alkenyl groups such as cis-9-octadecenyl. In addition, as halogen, Cl, Br, I, etc., as an alkoxy group, the alkyl part preferably has 4 to 22 carbon atoms. For example, octyloxy group, hexyloxy group, dodecyloxy group, β-hydroxyethoxy, etc., as haloalkoxy group, The number of carbon atoms in the alkyl moiety is preferably 4 to 22, and examples thereof include β-chloroethoxy and β-bromoethoxy. R 'may be a hydroxy group.

  Examples of the aliphatic divalent group having 1 to 50 carbon atoms represented by A include a divalent group such as an alkylene group, an alkyleneoxy group, a polyalkyleneoxy group, or an alkyleneoxy-alkylene group. Specific examples include ethylene, trimethylene, octamethylene, ethyleneoxy, polyethyleneoxy, polypropyleneoxy, and ethyleneoxy-trimethylene groups.

In the acidic group of any one of —COOM, —SO ₃ M, and —PO (OM) ₂ represented by X and the salt thereof, the M includes, for example, an alkaline earth such as sodium ion, potassium ion, lithium ion and the like Examples thereof include transition metal ions such as metal ions, calcium ions, barium ions, ammonium ions, silver ions and cadmium ions, alkylammoniums having 1 to 4 carbon atoms, quaternized ammonium ions or derivatives thereof.

  The compound represented by the formula (IV) preferably contains 5 mol% to 95 mol%, more preferably 10 mol% to 90 mol% of the monomer unit represented by the formula (III).

ただし、上記式中、Ｒ_０は炭素数４〜２２個の脂肪族炭化水素基を表わす。分子量は特に限定されないが、６００〜１０，０００が好ましく、９００〜５，０００がより好ましい。Examples of the monomer unit in the formula (III) and the formula (IV) include the following.

In the above formula, R ₀ represents an aliphatic hydrocarbon group having 4 to 22 carbon atoms. Although molecular weight is not specifically limited, 600-10,000 are preferable and 900-5,000 are more preferable.

さらに本発明では、式（Ｖ）で表される化合物から選択される１種以上の界面活性剤を使用することもできる。Specific examples of preferred polymers are shown below.

Furthermore, in this invention, 1 or more types of surfactant selected from the compound represented by Formula (V) can also be used.

（前記式（Ｖ）中、Ｒ_４は炭素数が１〜５０の脂肪族炭化水素又は芳香族炭化水素を表し、Ｘは−ＳＯ_３Ｍ、−ＣＯＯＭ又は−ＰＯ（ＯＭ）_２で表される酸性基またはそれらの塩を示し、Ｍは水素原子又は塩を形成しうるカチオン若しくはカチオン分子を表す）。Ｍは前記の通りである。Formula (V)

(In the formula (V), R ₄ represents an aliphatic hydrocarbon or aromatic hydrocarbon having 1 to 50 carbon atoms, and X is represented by —SO ₃ M, —COOM, or —PO (OM) _2. An acidic group or a salt thereof, and M represents a hydrogen atom or a cation or a cation molecule capable of forming a salt). M is as described above.

  The method for synthesizing these compounds is not particularly limited and can be appropriately selected from known synthetic methods according to the purpose. For example, as a synthesis of a formalin polycondensate of alkylphenol, Industrial Chemical Journal Vol. 66, 391 (1963), Oil Chemistry, Vol. 12, 625 (1963). Examples of methods for introducing sulfonic acid include Industrial Chemical Journal, Vol. 73, 563 (1970). 59, 221 (1956) and J. Am. Chem. Soc. 77, 2496 (1955) and the like.

  The present invention uses a water-insoluble organic solvent solution in which the water-insoluble organic solvent and the surfactant are dissolved in a water-insoluble organic solvent, and the interfacial tension with respect to water is 10 to 20 mN / m. The interfacial tension in the present invention means the surface tension measured by a method for measuring the interfacial tension of a liquid called the hanging drop method. In this method, as shown in a general textbook on surface tension, for example, Physics of Surface Tension (Yoshioka Shoten), page 57, by Dugenne Brosher Louvier Kele, its principle and concrete The technique is well known. More simply, it can be measured using an interfacial tension measuring device PD-W manufactured by Kyowa Interface Science Co., Ltd. (http://www.face-kyowa.co.jp/j/interface_chemistry/005.html). .

  With respect to the interfacial tension of the solution of the present invention, the water-insoluble polymer itself has little effect on the interfacial tension of the solution, and therefore the combination of the water-insoluble organic solvent and the surfactant used as well as the surfactant in the solution. Can be set according to the concentration of The combination and concentration may be determined by dissolving a surfactant in a water-insoluble organic solvent to prepare a water-insoluble solution and measuring the interfacial tension by the hanging drop method. Preferable examples include the use of DOPE or Cap for halogenated hydrocarbon solvents such as chloroform and dichloromethane or aromatic hydrocarbons such as toluene and benzene.

  Examples of the substrate material that can be used in the present invention include glass and silicon. In this case, the wettability of the substrate itself with respect to the water-insoluble organic solvent used can affect the thickness of the thin film formed on the substrate.

  Therefore, it is preferable to use a substrate having a high affinity with a water-insoluble organic solvent solution, or a substrate whose surface has been subjected to processing capable of increasing the affinity with a water-insoluble organic solvent solution. Such improvement of the wettability of the substrate is achieved by a method known per se, for example, an alkylated silane coupling treatment or a thiol compound for a glass or metal substrate, in accordance with the combination of the substrate material and the water-insoluble organic solvent to be used. A monomolecular film forming process by the above can be used.

  For example, as a substrate when using a hydrophobic organic solvent such as chloroform, it is preferable to use a sufficiently cleaned Si substrate, a glass substrate whose surface is modified with an alkylated silane coupling agent, or the like.

  In the present invention, a water-insoluble organic solvent solution containing a water-insoluble polymer and a surfactant as exemplified above is applied to a substrate to form a thin film of the same solution. May be 10 μm to 5 mm. If it is too thin, it may be a problem in terms of strength of the honeycomb-shaped porous body after manufacture, and if it is too thick, it may be a problem in terms of formation efficiency of pores.

  As a method of applying a water-insoluble organic solvent solution to a substrate, in addition to the above-described method of dropping the water-insoluble organic solvent solution onto a substrate, a bar coat, a dip coat, a spin coat method, and the like can be given. Any of the continuous types can be used.

  In the present invention, from the viewpoint of producing a honeycomb-shaped porous body having fine pores, a method of preparing a thin film by applying a water-insoluble organic solvent solution to a movable substrate is preferable. For example, such a method can be implemented by using an apparatus as shown in FIG. The apparatus of FIG. 1 has a substrate 1 that can move from the right to the left in the drawing at a predetermined speed, a metal plate 2 provided on the substrate 1, and a nozzle 3 that blows air having a predetermined relative humidity. Yes. Here, the metal plate 2 is placed on the substrate 1 with a gap corresponding to a desired thin film thickness.

  In this apparatus, the thickness of the thin film applied to the substrate 1 is changed between the substrate 1 and the metal plate 2 by passing the substrate 1 previously coated with the water-insoluble organic solvent solution under the metal plate. The thickness can be adjusted to be approximately equal to It is desirable to adjust the moving speed of the substrate 1 to 0.1 μm to 10 mm / second, particularly 1 to 5 mm / second.

  When this device principle is used, the honeycomb porous body formed on the substrate can be continuously recovered from the substrate, which is advantageous as an industrial production method for the honeycomb porous body of the present invention.

  By evaporating the water-insoluble organic solvent from the thin film placed on the substrate in this manner, a honeycomb-like porous body made of a water-insoluble polymer can be produced. At that time, by adjusting the evaporation rate of the solvent, the pore diameter of the honeycomb porous body can be made 100 nm or less. In particular, the water-insoluble organic solvent is evaporated by placing the thin film on the substrate in an air flow having a relative humidity of 30% or more and a flow rate of 0.1 to 100 L / min, preferably 1.0 to 50 L / min. Thus, a high-quality honeycomb porous body having a uniform pore diameter in the range of 1 to 100 nm can be produced.

  In this method, a thin film of a water-insoluble organic solvent solution is placed in an air stream having a relative humidity of 30% or more to quickly evaporate the solvent and suppress the growth of water droplets that are condensed on the surface of the solvent. The material is provided with pores smaller than 100 nm. The airflow rate in such a method may be appropriately adjusted according to the volatility of the solvent used and the thickness of the thin film on the substrate, but is generally 0.1 to 100 L / min, preferably 1.0 to 50 L / min. do it. In addition, as for the arrangement of the thin film with respect to the air flow direction, in the arrangement where the air flow is applied obliquely upward or perpendicular to the thin film on the substrate, the thin film may be distorted or cracked by the wind pressure due to the air flow. There is also a possibility. In such a case, it is preferable that the thin film is formed in parallel or upward with a thin film of the organic solvent solution on the substrate with respect to the airflow. In this case, the air flow may be generated by either positive pressure from the upstream side or negative pressure from the downstream side. For example, either predetermined air may be ejected from a nozzle installed toward the substrate, or air above the substrate may be sucked from one direction.

  According to the present invention, it is possible to manufacture a high-quality honeycomb-shaped porous body having a standard deviation of pore diameter of 10% or less in a 100-μm square honeycomb-shaped porous body. In addition, a high-quality honeycomb porous body having a fine pore diameter of 1 nm to 100 μm and a standard deviation of the pore diameter of 10% or less is obtained by evaporating the solvent under a constant air flow. Can do. Such a honeycomb-shaped porous body has a photonic crystal, an antireflection film, an optical film such as a light diffusing plate, an electronic material such as a patterned resist or an electrode mold, a cell culture substrate, and a uniform pore size. It can be used for the separation membrane used.

  The following examples illustrate the details of the present invention. However, these examples do not limit the present invention.

Poly (ε-caprolactone) (Wako Pure Chemical, molecular weight 70,000 to 100,000) as the water-insoluble polymer, n / m 4/1, number average molecular weight = 29,000, molecular weight 210,000 as the surfactant Compound 1 of general formula (I), and dioleylphosphatidylethanolamine (DOPE) in which R ₁ , R ₂ = C ₁₇ H ₃₃ and R ₃ = NH ₃ in formula (II) are used as a water-insoluble organic solvent and chloroform A honeycomb-like porous body was prepared by use.

  Chloroform solution (A) having a poly (ε-caprolactone) concentration of 5 mg / mL and the above compound 1 of 3.0 mg / mL, and chloroform having a poly (ε-caprolactone) concentration of 5 mg / mL and DOPE of 0.5 mg / mL Solution (B) was prepared. When the interfacial tension of both solutions with respect to water was measured by the hanging drop method (PD-W, Kyowa Interface Chemistry), the solution (A) was 18.6 mN / m and the solution (B) was 13.3 mN / m.

  5 ml of the solutions (A) and (B) were respectively dropped on a glass petri dish, and humidified air (relative humidity 80%, flow rate 2 L / min) was blown to evaporate the solvent to form a film (FIG. 2). The surface structure of the produced film was observed with an optical microscope, the porosity was calculated from the optical microscope image using image processing software (Image SXM, NIH, USA), and the standard deviation of the pore diameter was calculated.

  As a result, a high-quality honeycomb film having a standard deviation of the pore diameter of 10% or less was obtained from both solutions (A) and (B) (FIG. 3).

  On the other hand, a solution (C) having the same composition as the solution (B) was prepared except that the concentration of DOPE was 0.05 mg / mL, and the interfacial tension was measured. As a result, it was 25.8 mN / m. A honeycomb-like porous body was formed from this solution (C) by the same operation as described above, but the pore diameter of the obtained honeycomb-like porous body was clearly uneven (FIG. 4).

Polylactic acid (manufactured by SIGMA, molecular weight: 75,000 to 120,000) concentration of 5 mg / ml and dioleylphosphatidylethanolamine in formula (II) where R ₁ , R ₂ = C ₁₇ H ₃₃ , R ₃ = NH ₃ (DOPE) A chloroform solution (5.0 ml) having a concentration of 0.1 mg / ml was dropped on a glass petri dish, and humidified air (relative humidity 80%, flow rate 2 L / min) was sprayed to evaporate the solvent to form a film ( FIG. 5). The surface structure of the prepared film was observed with an optical microscope, and the porosity was calculated from the optical microscope image using image processing software (Image SXM, NIH, USA.), And the standard deviation of the pore diameter was calculated. The standard deviation was 10% or less.

The concentration of polystyrene (manufactured by Aldrich, molecular weight of about 280,000) is 5 mg / ml, and the dioleylphosphatidylethanolamine (DOPE) concentration in which R ₁ , R ₂ = C ₁₇ H ₃₃ and R ₃ = NH ₃ in formula (II) is A 0.1 ml / ml chloroform solution (5.0 ml) was dropped onto a glass petri dish, and humidified air (relative humidity 80%, flow rate 2 L / min) was blown to evaporate the solvent to form a film (FIG. 6). The surface structure of the prepared film was observed with an optical microscope, and the porosity was calculated from the optical microscope image using image processing software (Image SXM, NIH, USA.), And the standard deviation of the pore diameter was calculated. The standard deviation was 10% or less.

  A honeycomb-like porous body was prepared using a polyion complex as a surfactant. 319 mg of dimethyl-dioctadecyl-ammonium bromide (manufactured by Mutual Pharmaceutical Co., Ltd., hereinafter referred to as DDAB) was dispersed in 200 mL of pure water by applying ultrasonic waves. 917 mg of polystyrene sulfonate potassium salt (made by Showa Denko) was dissolved in 300 mL of pure water, and DDAB aqueous solution was added thereto. The produced precipitate was extracted with toluene, sodium sulfate was added for drying, and then the solvent was removed by a rotary evaporator. Excess solvent was removed by drying under reduced pressure to obtain 858 mg of polyion complex of the following formula (VI) (yield: about 82%).

ポリイオンコンプレックスをクロロホルムに溶解させ、１．０ｍｇ／ｍＬの溶液を調製した。本溶液を用いて、懸滴法を用いて水に対する界面張力を測定したところ、約１７ｍＮ／ｍであった。Formula (VI)

The polyion complex was dissolved in chloroform to prepare a 1.0 mg / mL solution. When this solution was used and the interfacial tension with respect to water was measured using the hanging drop method, it was about 17 mN / m.

  4 ml of a solution of polyion complex and polystyrene dissolved in chloroform so that the polyion complex concentration is 1.0 mg / mL and the polystyrene concentration is 10 mg / mL, cast into a 9 cm petri dish, and humidified air (humidity 40-50%). Sprayed at a flow rate of 4 L / min. The optical microscope image of the obtained film is shown in FIG. A honeycomb-like porous film having pores of about 3 microns arranged in hexagonal was obtained.

Polylactic acid (manufactured by Aldrich, molecular weight 70,000 to 100,000) 10 mg / ml and dioleyl phosphatidylethanolamine (DOPE) in which R ₁ , R ₂ = C ₁₇ H ₃₃ and R ₃ = NH ₃ in formula (II) 0. 20 ml of a chloroform solution containing 05 mg / ml was dropped onto a glass petri dish, and humidified air (relative humidity 80%, flow rate 2 L / min) was blown to evaporate the solvent to form a film (FIG. 8).

  A chloroform solution containing a poly (ε-caprolactone) concentration of 5 mg / mL and 0.5 mg / mL of the compound of formula (W-1) as a compound of formula (III) was prepared. When the interfacial tension of this solution with respect to water was measured by a hanging drop method (PD-W, Kyowa Interface Chemistry), it was 19.0 mN / m.

  5 ml of the solution was dropped on a glass petri dish, and humidified air (relative humidity 80%, flow rate 2 L / min) was sprayed to evaporate the solvent to form a film (FIG. 9). The surface structure of the prepared film was observed with an optical microscope, and the porosity was calculated from the optical microscope image using image processing software (Image SXM, NIH, USA.), And the standard deviation of the pore diameter was calculated. The standard deviation was 10% or less.

Claims (5)

The water-insoluble organic solvent dissolves the water-insoluble polymer and one or more surfactants represented by the following formula (II), formula (III), formula (IV) or formula (V), and has an interfacial tension of 10 Applying a water-insoluble organic solvent solution of ˜20 mN / m to a glass or metal substrate to prepare a thin film of the solution, and evaporating the organic solvent from the thin film on the substrate, A method for producing a honeycomb-shaped porous body made of a water-soluble polymer substance.
Formula (II)

(Wherein R ₁ and R ₂ are each independently selected from C _{11 to} C ₁₇ aliphatic hydrocarbon groups, and R ₃ is selected from N ⁺ (CH ₃ ) ₃ or NH ₃ ).
Formula (III)

Formula (IV)

(In the formula (III) and the formula (IV), R represents R ′ or R′O, and R ′ represents a hydrogen atom or an aliphatic hydrocarbon group having 4 to 22 carbon atoms, a halogen, a hydroxy group, Represents an alkoxy group or a haloalkoxy group, A represents an aliphatic divalent group having 1 to 50 carbon atoms, n represents an integer of 0 to 6, X represents —COOM, —SO ₃ M, — PO (OM) ₂ or an salt or hydroxyl groups, M represents a cation or cationic molecules capable of forming a hydrogen atom or a salt thereof, R _o represents a hydrogen atom or an aliphatic hydrocarbon group having a carbon number 4 to 22 amino The compound of the formula (III) may be a homopolymer consisting of a single monomer or a copolymer having the above R, A, n and X different in monomer units, and the compound of the formula (IV) may be the same or different in each monomer unit Different Or a random copolymer having the above R, A, n and X)
Formula (V)

(In the formula (V), R ₄ represents an aliphatic hydrocarbon or aromatic hydrocarbon having 1 to 50 carbon atoms, and X is represented by —SO ₃ M, —COOM, or —PO (OM) _2. An acidic group or a salt thereof, and M represents a hydrogen atom or a cation or a cation molecule capable of forming a salt)   The production method according to claim 1, wherein the surfactant represented by the formula (II) is dioleyl phosphatidylethanolamine, dipalmitoyl phosphatidylethanolamine or dimyristoyl phosphatidylcholine.   The production method according to claim 1 or 4, wherein the solvent is evaporated by placing a thin film under an air flow having a relative humidity of 30% or more and a flow rate of 0.1 to 100 L / min.   The manufacturing method according to any one of claims 1, 4, and 7, wherein a thin film is prepared by applying a water-insoluble organic solvent solution to a substrate while moving the substrate in a uniaxial direction.   The method according to any one of claims 1, 4, 7, and 8, wherein a substrate whose surface is modified with an alkylated silane coupling agent is used.

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