JP5509571B2 - Substrate with fine particle laminated thin film, method for producing the same, and optical member using the same - Google Patents

Description

  The present invention relates to a substrate with a fine particle laminated thin film, a method for producing the same, and an optical member using the same.

（ｎ_ｃは反射防止膜の屈折率、ｎ_ｓは基材の屈折率、ｎ_０は雰囲気の屈折率） In order to achieve a reflectance of 0% with a single layer as an antireflection film such as an optical member, a refractive index (n _c ) that satisfies the following equation is required (see Non-Patent Document 1).

(N _c is the refractive index of the antireflection film, n _s is the refractive index of the substrate, n ₀ is the refractive index of the atmosphere)

  For example, the refractive index in the visible region of a glass or plastic substrate, which is a transparent substrate used in a display, is about 1.52, and a value of about 1.25 taking the square root of the product with the refractive index 1 of air is The most ideal value. A film having such a refractive index is, for example, a porous film whose refractive index is controlled by the concentration of pores contained in the silica film. Moreover, in order to be transparent, it is required that the pore diameter of the gap is 100 nm or less, preferably 40 nm or less, which does not scatter light.

As a conventional method for producing a glass with an antireflection film, a method of forming a silicon dioxide film on the glass surface by, for example, a precipitation method is known. If the glass substrate is brought into contact with an immersion liquid in which an aqueous solution of silicofluoric acid is saturated with SiO ₂ powder and then an aqueous boric acid solution is added, deposition of the SiO ₂ film on the glass surface starts. Specifically, the anti-reflective film is characterized by removing the extraneous glass layer on the surface in advance when both surfaces of the glass plate are treated with a silica supersaturated aqueous solution of hydrofluoric acid to form an anti-reflective layer on both surfaces. A manufacturing method of glass with a film is known (Patent Document 1).

As another glass with an antireflection film, the uppermost layer on the air side of the glass substrate surface has fine irregularities of several tens to several hundreds of nm or pores having a diameter in the range of several tens to several hundreds of nm on the surface. And a mixed oxide of SiO ₂ or SiO ₂ and other oxides having a refractive index of 1.40 to 1.60 and a film thickness of 70 to 130 nm, and if necessary, an uppermost layer There is a glass with an antireflection film obtained by coating a silane compound containing a polyfluoroalkyl group on the surface (Patent Document 2).

  Furthermore, in this glass with an antireflection film, a coating in which two kinds of precursor sols having different average molecular weights as the oxide raw material solution, for example, precursor sols having an average molecular weight of several thousand and several hundred thousand are mixed. There is also a glass with an antireflection film in which pores are specifically expressed on the surface by controlling the mixing ratio of the precursor sol when the solution is coated and thermoformed into a thin film (Patent Document 3).

  As a method for forming a nanometer-scale thin film from a solution, an alternate lamination method has been proposed (see Non-Patent Document 2). A method of laminating fine particles such as silica, titania and ceria by an alternate laminating method has also been reported (see Non-Patent Document 3). The film in which the fine particles are laminated (fine particle laminated film) reflects the optical characteristics of the fine particles. For example, the silica fine particle laminated film has a low refractive index, and the titania fine particle laminated film has a high refractive index.

  However, when the fine particle laminated film is used as a part of a member for optical use, a practical surface hardness is required. The antireflection film located on the outermost surface is required to have a higher surface hardness, and even the internal optical member is required to have a surface hardness that does not cause scratches during assembly.

Here, it is necessary for laminating silica fine particles having a refractive index of 1.48 to form voids, and to form a thin film having a refractive index of 1.25 to 1.30, which can provide a sufficient antireflection film with a single layer. The volume density of the silica fine particles is approximately obtained from the Drude theory by the following formula (see Non-Patent Document 4).

（ｎ_ｃは薄膜の屈折率、ｎ_ＳｉＯ２はシリカ屈折率＝１．４８、ｎ_０は空気屈折率＝１、ρはシリカ微粒子の体積密度） therefore,

( _Nc is the refractive index of the thin film, n _SiO2 is the silica refractive index = 1.48, n ₀ is the air refractive index = 1, and ρ is the volume density of the silica fine particles)

  That is, the volume density of the silica fine particles to be 47% to 57%, in other words, the porosity of 43% to 53% is necessary. However, conventional porous membranes have a problem that the mechanical strength is further reduced by increasing the porosity, that is, by reducing the volume density of silica. In other words, the fine particle laminated film formed by the conventional alternating lamination method has a scratch resistance because the fine particles are adsorbed by weak interaction such as hydrogen bonding mainly due to polarization of a hydroxyl group or electrostatic attraction. There was a problem of inferiority.

Patent Document 4 describes that a fine particle laminated film is sealed by application of a transparent sealing material and cured to ensure strength and prevent deformation. Patent Document 5 describes that the scratches of the fine particle laminated film are improved by filling the voids in the fine particle laminated film with an actinic radiation reactive monomer and a polymerization initiator and curing them. Patent Document 6 discloses an antireflection method by contacting a photoelectric conversion element having an antireflection film formed of a fine particle laminated film with a trimethoxymethylsilane solution and condensing trimethoxymethylsilane with ammonia vapor or hydrochloric acid vapor. It describes that the adhesion of the film is improved. In Patent Document 7 and Patent Document 8, a graft polymer chain having a polar group is introduced onto a substrate by a surface graft polymerization method, and the substrate is formed by contacting the substrate once with the fine particle dispersion solution. It is described that the adsorption between the fine particle single layer film or the fine particle laminated film and the base material becomes strong. In Patent Document 9, a functional group in which an ester bond, a urethane bond, an amide bond, an ether bond, or the like is introduced is introduced into each of the transparent substrate surface and the fine particle surface to form a chemical and irreversible bond. It is described that adhesion on a transparent substrate is improved.
JP-A-57-166337 JP-A-5-330856 JP-A-5-147976 JP 2002-361767 A JP 2003-205568 A JP 2003-332604 A JP 2003-112379 A JP 2004-114339 A Japanese Patent Laid-Open No. 2002-6108 Optical thin film H_A_Macleod Translated by Shigetaro Ogura et al. P85-93 (Thin-film optical filters) Thin Solid Films, 210/211, p831 (1992) Langmuir, Vol. 13, (1997) p6195-6203) Thin Film / Optical Devices Authors Sadayoshi Yoshida, Hiroyoshi Yajima Publishers 1994 The University of Tokyo Press 34-42

  An object of the present invention is to provide a fine particle laminated thin film having a low refractive index, high adhesion, and excellent scratch resistance, a production method using an alternate lamination method, and a practically useful optical member using the same. It is.

  The present invention relates to a base material and a fine particle laminated thin film provided on the base material having voids, wherein the base material is alternately adsorbed on the base material and the alcoholic silica sol product. And the fine particles and the substrate with the fine particle laminated thin film characterized in that the fine particles and the fine particles are bonded to each other.

  The present invention relates to the following.

1. A base material, and a fine-particle laminated thin film having voids provided on the base material,
The fine particle laminated thin film alternately adsorbs electrolyte polymer and fine particles, and
A substrate with a fine particle laminated thin film, wherein the substrate and the fine particles, and the fine particles and the fine particles are bonded via an alcoholic silica sol product.

  2. Item 5. The substrate with a fine particle laminated thin film according to Item 1, wherein the fine particle laminated thin film has a porosity of 43% to 53%.

  3. Item 3. The fine particles according to item 1 or 2, wherein the alcoholic silica sol product comprises an alcoholic silica sol prepared by hydrolyzing a lower alkyl silicate represented by the general formula (1) in methanol and / or ethanol. Base material with laminated thin film.

Si (OR) ₄ (1)
(However, R represents a methyl group or an ethyl group.)
4). Item 4. The substrate with a fine particle laminated thin film according to any one of Items 1 to 3, wherein the primary particle size of the fine particles is 2 to 100 nm.

  5. Item 5. The substrate with fine particle laminated thin film according to any one of Items 1 to 4, wherein the fine particle is an inorganic oxide.

  6). Item 6. The fine particle laminated thin film according to Item 5, wherein the inorganic oxide is an oxide containing at least one element selected from the group consisting of silicon, aluminum, zirconium, titanium, niobium, zinc, tin, cerium, and magnesium. Base material.

  7). Item 7. The substrate with a fine particle laminated thin film according to any one of Items 1 to 6, wherein the fine particle is a bead-like fine particle aggregate.

  8). Item 8. An optical member comprising the substrate with a fine particle laminated thin film according to any one of Items 1 to 7.

  9. Item 9. The optical member according to Item 8, which has an antireflection function.

  10. Item 10. The optical member according to Item 8 or 9, which has a transflective function.

  11. Item 11. The optical member according to any one of Items 8 to 10, having a reflecting function.

12 Item 8. A method for producing a substrate with a fine particle laminated thin film according to any one of items 1 to 7, wherein the electrolyte polymer and the fine particles are alternately laminated on the substrate,
(A) A step of contacting or coating either the electrolyte polymer solution or the fine particle dispersion on the desired substrate surface,
(B) A step of contacting or applying an electrolyte polymer solution or fine particle dispersion which is not used in step A and having an opposite charge to the electrolyte polymer or fine particle dispersion used in step A ,
Furthermore, (C) The manufacturing method of the fine particle laminated thin film characterized by including the process of contacting or apply | coating an alcoholic silica sol solution.

  13. Item 13. The method for producing a fine-particle laminated thin film according to Item 12, wherein the step C is performed after alternately performing the step A and the step B one or more times.

  14 Item 14. The method for producing a fine-particle laminated thin film according to Item 12 or 13, comprising a rinsing step after the step A and / or the step B.

  15. Item 15. The method for producing a fine particle laminated thin film according to any one of Items 12 to 14, wherein the heat treatment is performed after the step C.

  16. Item 16. The method for producing a fine particle laminated thin film according to Item 15, wherein the temperature of the heat treatment is 20 ° C to 140 ° C.

  After forming the electrolyte polymer / fine particle laminated thin film produced by the alternating lamination method on the substrate surface, the base with the fine particle laminated thin film having low refractive index, high adhesion and excellent scratch resistance by applying alcoholic silica sol The present invention has led to the provision of a material, a production method using an alternate lamination method, and a practically useful optical member using the method.

  Hereinafter, the production method of the present invention and materials used will be described in detail.

  As shown in FIG. 1, the substrate with fine particle laminated thin film of the present invention includes a fine particle laminated thin film 10 having a substrate 1 and voids 4 provided on the substrate 1. The fine particle laminated thin film is configured such that the electrolyte polymer 2 and the fine particles 3 are alternately adsorbed and the base material 1 and the fine particles 3 and the fine particles 3 and the fine particles 3 are bonded via the alcoholic silica sol product 5. .

(Fine particles)
The fine particles used in the present invention preferably have an average primary particle diameter of 2 to 100 nm in a state dispersed in a solution in order to obtain transparency of the fine particle laminated thin film, from the viewpoint of securing the optical function of the fine particle laminated thin film. 2 to 40 nm is more preferable, and 2 to 20 nm is most preferable. Fine particles having an average primary particle diameter of less than 2 nm are difficult to form. When the average primary particle diameter is larger than 100 nm, it becomes easy to scatter visible light, and the transparency of the fine particle laminated thin film tends to be impaired. In addition, when the fine particle laminated thin film is formed by the alternating lamination method, the amount of change in the film thickness of the fine particle laminated thin film per one alternate lamination is usually about the same as the average primary particle diameter of the fine particles. Therefore, if the average primary particle size is too large, the accuracy of film thickness control is lowered, and it is difficult to obtain a film thickness with high accuracy in terms of optical function expression. As long as the film thickness controllability is not impaired, the fine particles may be primary particles or secondary particles of the type in which primary particles are aggregated.

  In the present invention, the average primary particle size and average secondary particle size of the fine particles can be measured using a known method. When primary particles are not aggregated but are dispersed in the fine particle dispersion, the average primary particle diameter can be measured by a dynamic scattering method. However, in the case of secondary particles or the like in which primary particles are aggregated, what is measured by the dynamic scattering method is not the average primary particles but the average secondary particle diameter. The average primary particle diameter in the secondary particles can be measured by a BET method or an electron microscope method. In the BET method, molecules with an occupied area such as nitrogen gas are adsorbed on the particle surface, the specific surface area is obtained from the relationship between the adsorbed amount and the pressure, and the specific surface area is converted from the conversion table into the particle diameter. The average primary particle size can be determined.

  In electron microscopy, first, fine particles are scooped up from a fine particle dispersion on a copper mesh on which an amorphous carbon film having a thickness of several tens of nm is formed, or fine particles are adsorbed on the amorphous carbon film. The fine particles are observed with a transmission electron microscope, and then the lengths of all the fine particles in the photographed image are measured, and the arithmetic average is obtained as the average primary particle diameter. Note that the number of fine particles for measuring the length is desirably 100 or more, and when the number of fine particles in one photographed image is less than 100, it is set to 100 or more using a plurality of photographed images. When the axial ratios of the particles are greatly different as in the case of columnar particles, the length of the minor axis is generally measured, and the arithmetic average is taken as the average primary particle diameter.

  Further, the fine particles in the above-mentioned particle size measurement may be obtained not only from the fine particle dispersion for preparing the fine particle laminated thin film but also from the fine particle laminated thin film. As a method of obtaining from the fine particle laminated thin film, the fine particle laminated thin film on the substrate is polished by steel wool (manufactured by Nippon Steel Wool Co., Ltd., # 0000) or a cutter to peel off the powdery fine particle aggregate, and the fine particle agglomerated material There is a method of applying ultrasonic waves to the aggregate in a solvent. As a result, fine particle aggregates and monodispersed fine particles having a reduced size can be obtained. As the solvent, water, an organic solvent, or a mixed solvent such as water and a water-soluble organic solvent can be used.

  In electron microscopy, the shape of the fine particles can be observed simultaneously with the particle size. It can be distinguished whether the particles are spherical or beaded. In the fine particles connected in a bead shape, primary particles are connected in a bead shape as shown in FIG. 2, and each primary particle is covalently bonded. In the fine particle film using beaded particles, due to the steric hindrance caused by the beaded shape, other beaded particles and the electrolyte polymer having the opposite charge cannot occupy the space closely, resulting in spherical particles. It has a higher porosity and a lower refractive index than the fine particle film using.

The fine particles in the present invention include inorganic fine particles. Specifically, lithium, sodium, magnesium, aluminum, zinc, indium, silicon, tin, titanium, zirconium, yttrium, bismuth, niobium, cerium, cobalt, copper, Halides and oxides such as iron, holmium, and manganese are used, and more specifically, lithium fluoride (LiF), sodium fluoride (NaF), magnesium fluoride (MgF ₂ ), aluminum fluoride (AlF ₃ ), aluminum oxide (Al ₂ O ₃ ), zinc oxide (ZnO), indium tin oxide (ITO), silica (SiO ₂ ), tin oxide (SnO ₂ ), titanium oxide (TiO ₂ ), zirconium oxide _(ZrO 2), yttrium oxide _{(Y 2 O} 3), bismuth oxide (B ₂ O _3), niobium oxide _{(Nb 2 O} 5), ceria _(CeO 2), cobalt oxide (CoO), copper (CuO), iron _{(Fe 2 O} 3), holmium _{(Ho 2 O} 3), manganese (Mn ₃ O ₄ ) and the like, and these can be used alone or in admixture of two or more.

  More preferably, an oxide containing at least one element selected from the group consisting of silicon, aluminum, zirconium, titanium, niobium, zinc, tin, cerium, and magnesium is preferably selected from the viewpoint of transparency.

  The fine particles may be indeterminate, and there are no particular limitations on the crystal form that can be obtained. For example, TiO2 may be rutile or anatase. Commercially available products of such inorganic fine particles include, for example, titania fine particle aqueous dispersion (Tynoch M-6) manufactured by Taki Chemical Co., Ltd., and zinc oxide fine particle aqueous dispersion (ZnO-350) manufactured by Sumitomo Osaka Cement Co., Ltd. Ceria fine particle aqueous dispersion (Nydral P10) manufactured by Taki Chemical Co., Ltd., tin oxide fine particle aqueous dispersion (Cerames S-8) manufactured by Taki Chemical Co., Ltd., and niobium oxide fine particle water manufactured by Taki Chemical Co., Ltd. A dispersion liquid (Bilar NB-X10), an alumina fine particle water dispersion liquid (Alumina Sol-5) manufactured by Nissan Chemical Industries, Ltd., a silica fine particle water dispersion liquid (Snowtex 20) manufactured by Nissan Chemical Industries, Ltd., and the like can be used.

Among the above inorganic fine particles, silica (SiO ₂ ) is preferable in that a thin film having a low refractive index required for an antireflection film can be obtained, and water-dispersed colloidal silica (average primary particle diameter controlled from 1 nm to 23 nm) ( Most preferred is SiO ₂ ). Examples of such commercially available inorganic fine particles include Snowtex (manufactured by Nissan Chemical Industries). In order to obtain a lower refractive index, it is more preferable that the basic fine particles contain a bead-shaped particle shape as shown in FIG. Examples of commercially available products include Snowtex UP or Snowtex OUP series (Nissan Chemical Industry Co., Ltd.) and Fine Cataloid F120 (Catalyst Kasei Kogyo Co., Ltd.), and pearl necklace silica sol.

  Regardless of which fine particles are used, when the fine particles are adsorbed on the substrate, it is preferable that the fine particles are applied or contacted in the form of a dispersion to be adsorbed on the substrate.

(Fine particle dispersion)
The fine particle dispersion used in the present invention is obtained by dispersing the above-mentioned fine particles in a medium (liquid) which is a mixed solvent such as water, an organic solvent, or water and a water-soluble organic solvent. Examples of the water-soluble organic solvent include methanol, ethanol, propanol, acetone, dimethylformamide, acetonitrile and the like. The proportion of fine particles in the fine particle dispersion is usually preferably about 0.01 to 30% (weight), and the fine particles can be dispersed by a known method.

  When the dispersibility of the fine particles is low, a so-called dispersant can be used when preparing the fine particle dispersion in order to improve the dispersibility. As such a dispersant, a surfactant, an electrolyte polymer, a nonionic polymer, or the like can be used. The amount of these dispersants to be used varies depending on the type of the dispersant to be used, but generally it is preferably about 0.001 to 0.1% (weight) in the fine particle dispersion. Separation occurs, or the fine particles become electrically neutral in the dispersion, and the fine particle laminated thin film cannot be obtained.

  The pH of the fine particle dispersion can be adjusted in the range of 1 to 13 with an alkaline aqueous solution such as sodium hydroxide or potassium hydroxide or an acidic aqueous solution such as hydrochloric acid or sulfuric acid, and the pH can also be adjusted with a dispersant. . As the pH of the fine particle dispersion deviates from the equipotential point, the electrostatic attractive force with the substrate or the electrolyte polymer tends to increase. The equipotential point is a pH value at which the surface potential of the fine particles becomes 0 and the electrostatic repulsion force disappears, so that the particles aggregate. However, the equipotential point varies depending on the number of surface hydroxyl groups and the crystal structure. It depends on the material.

  The kind of fine particles contained in the fine particle laminated thin film is not limited to one. For example, two or more kinds of fine particles adsorbed in one contact of the fine particle dispersion may be used, and the kind of fine particles may be different for each contact of the fine particle dispersion.

  The charge of the fine particles refers to the charge (voltage) in the solution determined by measuring the zeta potential. In a system in which nano-sized fine particles are dispersed in an aqueous medium, a solid-liquid interface moves with each other, and a potential difference (zeta potential) is generated at the interface. That is, there is a stationary phase (or adsorption phase) at the interface between the solid and the liquid, and ions having a charge opposite to that of the solid surface are adsorbed. When the solid and the liquid are in relative motion, the potential difference between the stationary phase and the liquid is the zeta potential. The surface potential and ζ potential are energy resulting from the electric field generated by the electric double layer. The zeta potential is affected by the charge on the particle surface and adsorbed species. In aqueous solution, this potential changes with pH, suggesting changes in surface conditions and adsorbed species. For example, many oxide fine particles exhibit anionic properties derived from surface hydroxyl groups, and in a high pH state (alkaline), dissociation between hydroxyl groups-OH and OH progresses more, and the negative charge of the zeta potential is increased. On the contrary, when the pH is increased and the pH is low (acidic), the charge of the zeta potential is decreased. In addition, in the fine particles dispersed by the ionic dispersant, the dispersant is adsorbed on the fine particles, so that if the dispersant contains a cationic such as an amino group or an ammonium ion, a positive zeta If it is anionic such as a carboxyl group or a sulfonium ion, it shows a negative zeta potential.

(Electrolytic polymer)
As the electrolyte polymer used in the present invention, a polymer having a charged functional group in the main chain or side chain can be used. This functional group separates the electrolyte polymer into anionic and cationic polymers.

  The polyanion generally has a negatively charged functional group such as sulfonic acid, sulfuric acid, and carboxylic acid. For example, polystyrene sulfonic acid (PSS), polyvinyl sulfate (PVS), dextran sulfate, chondroitin Sulfuric acid, polyacrylic acid (PAA), polymethacrylic acid (PMA), polymaleic acid, polyfumaric acid and the like are used.

  The polycation generally has a positively charged functional group such as a quaternary ammonium group or amino group, such as polyethyleneimine (PEI), polyallylamine hydrochloride (PAH), polydiallyldimethyl. Ammonium chloride (PDDA), polyvinyl pyridine (PVP), polylysine and the like can be used. Any of these organic polymer ions is water-soluble or soluble in a mixed solution of water and an organic solvent.

(Alcohol-based silica sol)
As the alcohol-based silica sol, 4, 3, and bifunctional alkoxysilanes, and condensates, hydrolysates, silicone varnishes, and the like of these alkoxysilanes can be used. Specifically, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane as tetrafunctional alkoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, Vinyltrimethoxysilane, vinyltriethoxysilane, methacryloxypropyltrimethoxysilane, glycidpropoxytrimethoxysilane, glycylpropylpropyldiethoxysilane, aminopropyltriethoxysilane, aminoethylaminopropyltrimethoxysilane, mercaptopropyltrimethoxy Silanes, bifunctional alkoxysilanes include dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyl Such as diethoxy silane. Examples of the condensate include, but are not limited to, condensates of tetrafunctional alkoxysilanes such as ethyl silicate 40, ethyl silicate 48, and methyl silicate 51 manufactured by Colcoat Co., Ltd. Moreover, as a hydrolyzate, what hydrolyzed the alkoxysilane using the organic solvent, water, and the catalyst can be used.

  Among these silica compounds, in the alcoholic silica sol applied to the present invention, R is a methyl group or an ethyl group as the lower alkyl silicate of the general formula (1). In particular, tetramethoxysilane, tetraethoxysilane, ethyl silicate 40, ethyl silicate 48, methyl silicate 51, and alcoholic silica sol which is a hydrolysis product thereof are particularly preferable because they can firmly fix the film and are relatively inexpensive. It is. The alcoholic silica sol may be a mixture thereof.

(Alcoholic silica sol product)
The alcoholic silica sol product consists of (1) the alcoholic silica sol itself, (2) -SiOMe of the alcohol silica sol changed to -SiOH, (3) a polymer of silica sol, and (4) fine particles of the alcoholic silica sol. After contacting the laminated film, silanol groups (-Si-OH) contained in the molecules of the alcoholic silica sol undergo dehydration condensation with hydroxyl groups (-OH) contained in the fine particle laminated film, resulting in -Si-O- bonds. Modified silica sol.

As an example of a method for producing an alcohol-based silica sol, a known method can be used (see JP-A-6-52796). Specifically, tetramethoxysilane or tetraethoxysilane is used in an amount of about 10 to 20 times the number of moles of water and the catalyst, and at room temperature to 50 ° C (preferably room temperature to 30 ° C) for 1 hour or more. (Preferably 2 to 5 hours) The hydrolysis reaction is carried out with stirring. An alcoholic silica sol having a solid content concentration of 20 wt% or less, preferably 1 to 10 wt%, as the SiO ₂ concentration is prepared.

The alcoholic silica sol thus prepared can be diluted with a dilution medium so that it can be easily applied. Examples of this type of diluent include alcohols such as methanol, ethanol, n-propanol, 2-propanol, n-butanol and 2-butanol, esters such as ethyl acetate and butyl acetate, ketones such as methyl ethyl ketone, and the like. Examples thereof include a mixed solvent. These diluted solutions may be diluted by adding to the alcoholic silica sol, and the SiO ₂ concentration may be a solid content concentration of 0.1 wt% or more and less than 0.5 wt%. In order to apply the alcoholic silica sol solution to the substrate, any of a spray method, a dip method, a roll coat method, a spin coat method and the like can be used. After coating, the diluting medium is evaporated by heating at a temperature of 20 ° C. to 140 ° C., and at the same time, the silanol groups formed in the alcoholic silica sol are bonded to the fine particles and the substrate to form a bridge. It becomes an agent, and adhesion with the substrate of the fine particle laminated thin film is obtained.

(Base material)
Examples of the material for the substrate include resins, semiconductors such as silicon, metals, and inorganic compounds. Moreover, the shape is arbitrary, such as a shape which has a film, a sheet | seat, a board, and a curved surface. If a part or the whole of the substrate can be immersed in a solution such as a cylinder, thread, fiber, or foam, the fine particle laminated thin film is formed on the surface, and can be used. Moreover, even if the cross section of the substrate has an uneven shape, the fine particle laminated thin film can be formed following the surface structure. Even if the substrate surface has a nanometer-scale or submicron-scale structure, the fine particle multilayer thin film can be formed following the structure.

  Examples of the metal include iron, copper, white copper, titanium, and the like, which are subjected to a treatment such as forming an oxide film so that electric charges exist on the surface. Examples of the inorganic compound include glass and ceramics, and have a polar group on the surface.

  The material of the resin is not particularly limited. For example, polyester, polystyrene, cellulose acetate, polypropylene, polyethylene, polyamide, polyimide, polyethersulfone, polysulfone, polyvinyl acetal, polyetherketone, polychlorinated Examples thereof include stretched or unstretched transparent plastic films such as vinyl, polyvinylidene chloride, polymethyl acrylate, polymethyl methacrylate, polycarbonate, and polyurethane.

  Polar surfaces may be introduced by subjecting these substrate surfaces to corona discharge treatment, glow discharge treatment, plasma treatment, ultraviolet irradiation, ozone treatment, chemical etching treatment with alkali, acid, or the like. You may use resin which introduce | transduced the polar group by such a process.

When the fine particle laminated thin film is used as an optical member that requires transparency, it is desirable that the substrate is also transparent. As a substrate having transparency itself, for example, polyester such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyethylene, polypropylene, polystyrene, triacetyl cellulose, diacetyl cellulose, acetate butyrate cellulose, polyethersulfone, A thermoplastic resin such as polyamide, polyimide, polymethylpentene, polyvinyl chloride, polyvinyl alcohol, polyvinyl acetal, polymethyl methacrylate, polycarbonate, polyurethane, or a glass substrate is used. Moreover, when using the fine particle laminated thin film as an optical member in which only reflectance is important, transparency is not necessarily required for the base material, and a semiconductor, metal, or the like can be used.
To prevent contact between the fine particle dispersion and the substrate, such as by sticking an adhesive film, on the surface of a part of the base material where formation of the fine particle laminated thin film is not desired, onto the substrate of the fine particle laminated thin film Can be prevented.

  An adhesive layer is formed on the surface of the base material opposite to the antireflection film formed on the base material, and is attached to a glass substrate on the display surface as the adherend, so that the antireflection film faces the air It can also be used.

The fine particle laminated thin film 10 of the present invention can be manufactured by the following steps (see FIG. 1):
(A) Forming a layer of electrolyte polymer 2 or fine particles 3 on the substrate surface 1 by a step of contacting or applying either an electrolyte polymer solution or a fine particle dispersion;
(B) An electrolyte polymer solution or fine particle that has not been used in the step A and that has an opposite charge to the electrolyte polymer or fine particle used in the step A is contacted or applied. A layer of fine particles 3 or an electrolyte polymer 2 is formed by the step; and (C) the substrate 1, the fine particles 3, and the fine particles 3 through the alcoholic silica sol product 5 by the step of contacting or applying the alcoholic silica sol solution. And fine particles 3 are combined.

(Pretreatment method of substrate)
The substrates can be used as they are, or the surfaces thereof have a polarity by corona discharge treatment, glow discharge treatment, plasma treatment, ultraviolet irradiation, ozone treatment, chemical etching treatment with alkali or acid, silane coupling treatment, etc. Introduce groups to make the surface charge of the substrate negative or positive. Alternatively, as a method for efficiently introducing charges onto the substrate surface, PDDA (polydiallyldimethylammonium chloride) or PEI (polyethyleneimine), which is a strong electrolyte polymer, and an aqueous solution of PSS (polystyrene sulfonic acid) are alternately contacted. It is also possible to form alternating laminated films (see Advanced Material. 13, 51-54 (2001)).

(Formation method of fine particle laminated thin film)
In the present invention, it is preferable to use an alternating lamination method in order to produce a fine particle laminated thin film having voids. According to this method, a fine particle laminated film having a desired porosity can be obtained from known values disclosed in the following documents. Therefore, the refractive index after the alcoholic silica sol is applied to the fine particle laminated film and the solvent is volatilized can be controlled by the concentration of the alcoholic silica sol.

  The porosity can be adjusted by adjusting the pH of the fine particle dispersion used in the production of the fine particle laminated thin film (the porosity is relatively high when the pH is adjusted to 3 to 9, and the porosity is relatively low in other ranges). And so on) by adjusting the surface potential of the fine particles. The porosity is preferably 43 to 53% in consideration of the refractive index that provides a sufficient antireflection film. As a method for controlling the surface potential of the fine particles, the methods described in JP-A-2006-301125, JP-A-2006-297680, and JP-A-2006-301124 can be used. For example, after setting the porosity to 63% and applying an alcoholic silica sol solution having a weight concentration of 0.4%, the desired porosity can be set to 53%.

(Formation equipment for fine particle laminated thin film)
As an apparatus for forming a fine particle laminated thin film, an arm called a dipper that automatically moves an arm on which a base material is fixed and contacts the base material in a fine particle dispersion according to a program (J. Appl. Phys., Vol. 79, pp. 7501-7509, (1996), Japanese Patent Application No. 2000-568599). Moreover, you may use the continuous film formation process which takes out a film from the film wound up in roll shape, makes it contact in fine particle dispersion liquid as it is, and winds up a film in roll shape after making it dry.

  A base material is alternately immersed in an electrolyte polymer solution (polycation or polyanion) and a fine particle dispersion to form a fine particle laminated thin film on a solid substrate. If the surface charge of the substrate is negative, it is first contacted with a cationic solution (one of the electrolyte polymer or fine particle dispersion) and then contacted with an anionic solution (the other of the electrolyte polymer or fine particle dispersion). The contact time is appropriately adjusted depending on the polymer, fine particles, and film thickness to be laminated. After contacting the substrate with a cationic or anionic solution, the excess solution can be washed away with a solvent-only rinse before contacting the oppositely charged solution. Since it is adsorbed electrostatically, it does not peel off in this step. Further, it may be carried out in order to prevent a polymer electrolyte or fine particles not adsorbed from being brought into a solution having an opposite charge. If this is not done, cation and anion may be mixed in the solution by bringing it in, and precipitation may occur.

  As an apparatus, an alternate lamination apparatus called a dipper may be used. A substrate is attached to a robot arm that moves vertically and horizontally, and at a programmed time, the substrate is immersed in a cationic solution, subsequently immersed in a rinse solution, subsequently immersed in an anionic solution, and then immersed in a rinse solution. This process is one cycle, and the number of times of lamination can be continuously and automatically performed. The program may be a combination of two or more kinds of cationic substances and anionic substances. For example, the first two layers can use a combination of polydimethyldiallylammonium chloride and sodium polystyrene sulfonate, and the next 10 layers can use a combination of polydimethyldiallylammonium chloride and anionic silica sol.

  Take out the film wound up in roll form from the unwinding part, arrange the cationic solution water tank, rinse water tank, anionic water tank, rinse water tank in the middle, arrange the number of times you want to stack this arrangement and finally dry the process etc. It is also possible to use a continuous film forming process on a film-like substrate which is arranged and provided with a winding part.

  The obtained fine particle laminated thin film may be coated with a fluorine polymer solution or a fluorine coupling agent solution in order to impart antifouling properties. The concentration of the solution is preferably 0.1 to 5% by weight. If it is less than 0.1% by weight, sufficient antifouling properties may not be obtained. This is because the surface of the fine particle laminated film soaks into the interior and the antifouling component hardly remains on the surface. Moreover, when it exceeds 5 weight%, a desired porosity may not be obtained. This is because the volume occupied by the antifouling component fills the gap. In addition, since the valley portion of the fine shape is filled, the shape changes, and in the case of a base material having a function of bending light such as a lens, the characteristics may be deteriorated.

(Determination of refractive index and film thickness of fine particle laminated thin film)
The refractive index and film thickness of the fine particle laminate film can be obtained from the surface reflectance spectrum by an analysis program of an instantaneous photometric spectrophotometer (Filmetrics Co., Ltd., F20) that combines reflectance spectroscopy and curve fitting. .

（ただし、式中、ｎ_Ｐは微粒子を構成する物質の屈折率、ｎ_０は空気の屈折率＝１．０を示す。） (Determination of porosity of fine particle laminated thin film)
In the fine particle laminated thin film of the present invention, the gap between the fine particles is air. That is, since holes can be observed by surface and cross-sectional observation with a scanning electron microscope, when the apparent refractive index of the silica fine particle laminated thin film is lower than that of silica, the refractive index is lowered by the air present in the holes. I understand that there is. From this assumption, the porosity ρ ₀ in the fine particle laminated thin film can be obtained from the following equation.

(In the formula, n _P represents the refractive index of the substance constituting the fine particles, and n ₀ represents the refractive index of air = 1.0.)

    Examples of the low refractive index film of the present invention will be described below. Hereinafter, “part” means “part by weight”.

(Adsorption of electrolyte polymer and fine particles to substrate)
As fine particles, beaded silica fine particles having an average primary particle diameter of 8 nm measured by the BET method were used. Silica water dispersion 1.0% by weight (Snowtex (ST) OUP, manufactured by Nissan Chemical Industries, Ltd., silica sol, anionic) is used as a fine particle dispersion, and polydiallyldimethylammonium chloride (PDDA, average molecular weight 100000, manufactured by Aldrich) , Cationic) was used as the electrolyte polymer. As a solution, a 0.3 wt% PDDA aqueous solution and a 1.0 wt% fine particle dispersion were prepared. The pH of the fine particle dispersion was adjusted to 4 and the pH of the aqueous PDDA solution was adjusted to 9. A silicon substrate (150 mmφ, 0.7 mm thickness) is immersed in an aqueous PDDA solution for 1 minute, immersed in ultrapure water for rinsing for 3 minutes (a), immersed in a fine particle dispersion for 1 minute, The step (a) of immersing in pure water for 3 minutes was performed in this order. This step (a) once and step (b) once were sequentially performed as one cycle, and this cycle was repeated three times (the number of times of alternating fine particle lamination) to form a substrate on which the electrolyte polymer and fine particles were adsorbed.

(Synthesis of alcoholic silica sol)
<Methyl silicate alcoholic silica sol>
61.5 g of tetramethoxysilane was placed in 1 l (liter) of a four-necked round bottom flask, 463.9 g of MeOH was added, and the liquid temperature was kept constant at 30 ° C. to make the liquid uniform. Next, an aqueous solution in which 3.0 g of HNO ₃ ; 3.0 g was added to 71.6 g of water, and the mixture was stirred at 30 ° C. for 5 hours. This methyl silicate alcoholic silica sol (50 parts) and isopropyl alcohol (50 parts) were mixed, and n-butyl alcohol was added to adjust the solid content concentration to a predetermined concentration.

<Ethyl silicate alcoholic silica sol>
85.7 g of tetraethoxysilane was placed in 1 l of a four-necked round bottom flask, 356.7 g of MeOH was added, and the mixture was stirred while maintaining the liquid temperature constant at 30 ° C. to make the liquid uniform. Next, an aqueous solution obtained by adding 3.0 g of HNO ₃ ; to 154.6 g of water was added and stirred at 30 ° C. for 5 hours. This ethylsilicate alcoholic silica sol (50 parts) and isopropyl alcohol (50 parts) were mixed, and n-butyl alcohol was added to adjust the solid content concentration to a predetermined concentration.

Example 1
The substrate on which the electrolyte polymer and fine particles are adsorbed is set on a spin coater, and 20 ml of the methyl silicate-based alcoholic silica sol (0.4% solid content concentration) is developed on the entire substrate, and then the rotational speed is 1000 rpm. Rotated for 30 seconds. Then, it heated for 60 second with the hotplate heated at 80 degreeC, and produced the base material with a fine particle laminated thin film which couple | bonded the microparticles | fine-particles and silica sol, and microparticles | fine-particles and a board | substrate.

(Example 2)
A substrate with a fine particle laminated thin film was prepared in the same manner as in Example 1 except that the ethyl silicate alcoholic silica sol (0.4 wt% solid content concentration) was used instead of the methyl silicate alcoholic silica sol. .

(Example 3)
A mixture of 50 parts each of methyl silicate-based alcoholic silica sol (0.2 wt% solid content concentration) and ethyl silicate-based alcoholic silica sol (0.2 wt% solid content concentration), and 20 ml developed over the entire substrate, Rotation was performed at 1000 rpm for 30 seconds. Then, it heated for 60 second with the hotplate heated at 80 degreeC, and produced the base material with a fine particle laminated thin film which couple | bonded the microparticles | fine-particles and silica sol, and microparticles | fine-particles and a board | substrate.

(Example 4)
In the same manner as in Example 1, except that an acrylic resin plate (Sumitex, 100 mm × 150 mm × 1 mm thickness) was used instead of a silicon substrate, a fine particle laminated thin film was attached in the same manner as in Example 1. A substrate was prepared.

(Example 5)
Substrate with fine particle laminated thin film in the same manner as in Example 1 except that a PET film (A4100, 100 mm × 150 mm × 125 μm thickness) was used instead of the silicon substrate, and the same fine particle laminated thin film was used. Was made.

(Example 6)
In the same manner as in Example 1, except that a glass plate (BK-5 glass substrate, manufactured by Matsunami Co., Ltd., 25 mm × 75 mm × 0.7 mm thickness) was used instead of the silicon substrate, A substrate with a fine particle laminated thin film was prepared.

(Example 7)
Instead of a silicon substrate, a substrate in which a hemispherical lens shape having a diameter of 10 μm and a height of 4 μm is formed on a silicon substrate by a photosensitive resin (UV6, positive resist manufactured by Shipley Far East Co., Ltd.) is used. A substrate with a fine particle laminated thin film was produced in the same manner as in Example 1 except that the same fine fine particle laminated thin film was used. When the refractive index, the film thickness, and the porosity of the fine particle laminated thin film were measured, they were 1.26, 100 nm, and 51%, respectively.

(Comparative Examples 1-7)
As a comparative example, a substrate with a fine particle laminated thin film was prepared in the same manner as in Examples 1 to 7, except that the alcoholic silica sol was not spin-coated.

  About the base material with a fine particle laminated thin film by Examples 1-7 and Comparative Examples 1-7, the refractive index, the film thickness, the porosity, adhesiveness, and scratch resistance were measured and evaluated as follows.

(Determination of refractive index and film thickness of fine particle laminated thin film)
The refractive index and film thickness of the fine particle multilayer film were determined from the spectrum of the surface reflectance by an analysis program of an instantaneous photometric spectrophotometer (manufactured by Filmetrics Co., Ltd., F20) combining reflectance spectroscopy and curve fitting.

（ただし、式中、ｎ_Ｐは微粒子を構成する物質の屈折率、ｎ_０は空気の屈折率＝１．０を示す。） (Determination of porosity of fine particle laminated thin film)
In the fine particle laminated thin film of the present invention, the gap between the fine particles is air. That is, since holes can be observed by surface and cross-sectional observation with a scanning electron microscope, when the apparent refractive index of the silica fine particle laminated thin film is lower than that of silica, the refractive index is lowered by the air present in the holes. I understand that there is. From this assumption, the porosity ρ ₀ in the fine particle laminated thin film was obtained from the following equation.

(In the formula, n _P represents the refractive index of the substance constituting the fine particles, and n ₀ represents the refractive index of air = 1.0.)

(Evaluation method for adhesion)
Adhesive tape (NO.31B, polyester adhesive tape, manufactured by Nitto Denko) is attached and peeled off in order to measure the adhesion strength of the fine particle laminated thin film, and the fine particle laminated thin film is easily peeled off from the base material. When it moved to, it was determined that the adhesion was insufficient. The peel strength of the adhesive tape with respect to the PET film was 6 N / 19 mm (3 N / 10 mm). The peel strength is measured using Tensilon (constant speed extension type tensile tester, manufactured by Orientec, RTM-10, temperature: room temperature, test method: T-type peeling, peeling speed: 0.2 m / min), Adhesion was evaluated using the load at the time of peeling as the peel strength. The adhesiveness was evaluated as ◯ for a film having no change when it was peeled off after pasting the adhesive tape, and x when no film was left.

(Scratch resistance evaluation method)
The scratch resistance was evaluated by pencil hardness. The measuring method was measured as follows based on JIS standard (JIS-K-5400-1990). First, the sample was pressed against a pencil fixed at an angle of 45 ° with respect to the sample. The load applied by the pencil to the sample was 1.00 ± 0.05 kg. The pencil powder adhering to the sample was blown with air, and the remaining pencil powder was removed by pressing a plastic eraser (PE01, made by dragonfly pencil). When scratches that slightly bite on the surface of the film were seen, it was determined that “scratched”. The pencil hardness symbol of the sample when the film was scratched twice or more in five tests was defined as the pencil hardness of the sample. For example, a pencil hardness of a sample in which a 2H pencil scratches twice and an H pencil scratches once is H.

The evaluation results of the obtained fine particle laminated thin film are shown in Table 1.

(Example 8)
<Adsorption of electrolyte polymer and fine particles to substrate>
The pH of the silica aqueous dispersion (manufactured by Nissan Chemical Industries, Ltd., trade name: SNOWTEX (ST) OUP, silica sol) in which bead-like silica fine particles having an average primary particle diameter of 8 nm measured by the BET method are dispersed is not adjusted. As an electrolyte polymer aqueous solution, an aqueous solution in which polydiallyldimethylammonium chloride (PDDA, manufactured by Aldrich) was adjusted to 0.1% by weight and pH 10 was used as a fine particle dispersion having a concentration adjusted to 1% by weight.

  Silicon substrate (SUMCO CO., 6PW-A1, 6 inch Φ, 625 μm thickness), glass substrate (manufactured by Matsunami Glass Co., Ltd., trade name: S1111, 25 mm × 75 mm × 0.7 mm thickness, wavelength 550 nm) Refractive index is 1.54), PDDA aqueous solution is dropped onto each polystyrene plate (manufactured by Hikari Co., Ltd., transparent, 1 mm thickness) irradiated with UV light for 2 minutes with a low-pressure mercury lamp (10 mW) and rinsed after 1 minute A step (a) of showering the ultrapure water for 1 minute and a step (a) of dropping the fine particle dispersion and showering the ultrapure water for rinsing for 1 minute after the elapse of 1 minute were performed in this order. Performing the step (a) once and the step (b) once in order was defined as one cycle, and this cycle number was defined as the number of fine particle alternating laminations. The base material on which the electrolyte polymer and the fine particles were adsorbed was formed by performing the fine particle alternating lamination four times.

<Synthesis of alcoholic silica sol product and treatment using the same>
50 g of an ethoxysilane oligomer (Colcoat Co., ethyl silicate 40) was placed in a 300 ml three-necked round bottom flask, 42 g of MeOH was added, and the mixture was stirred at 25 ° C. to make the solution uniform, and then H ₃ PO ₄ 0.05 wt% 7.4 g of an aqueous solution was added and stirred at 25 ° C. for 72 hours to obtain a silicon compound solution having a silane concentration of 50%. 1-butanol was added to the silicon compound solution to obtain a silicon compound treatment liquid in which the silane concentration was adjusted to 1% by weight. The substrate on which the electrolyte polymer and fine particles were adsorbed was set on a spin coater, and 20 ml of the silicon compound treatment solution was spread on the entire substrate, and then spread and dried at a rotation speed of 1000 min ⁻¹ . Then, it dried at 25 degreeC for 24 hours, and produced the base material with a fine particle laminated thin film.

<Evaluation of refractive index>
As a result of evaluating the refractive index and film thickness of a low refractive index film (fine particle laminated thin film) on a silicon wafer with an automatic ellipsometer (manufactured by Fibrabo Co., Ltd., trade name: MARY-102, laser wavelength 632.8 nm) The refractive index of the refractive index film was 1.25, and the thickness was 110 nm.

<Evaluation of transparency>
As a result of measuring the haze value of the glass substrate on which the low refractive index film obtained above was formed in accordance with JIS K 7361-1-1997 with a turbidimeter (manufactured by Nippon Denshoku Industries Co., Ltd.), 0.4% Met. The haze value of the glass substrate alone was measured in the same manner and was found to be 0.1%. The turbidity of the low refractive index film was determined by subtracting the haze value of only the solid substrate from the haze value of the solid substrate on which the low refractive index film was formed. As a result, it was found that the turbidity of the low refractive index film was 0.3%, and the transparency of the low refractive index film was very high.

<Evaluation of antireflection performance>
When the transmission spectrum of the glass substrate on which the low refractive index film is formed is measured with a visible ultraviolet spectrophotometer (trade name: V-570, manufactured by JASCO Corporation), the maximum transmittance at a wavelength of 400 to 800 nm is 95%.

  In addition, a black adhesive tape (manufactured by Nichiban Co., Ltd., trade name: VT-196) is attached to the opposite surface of the glass substrate on which the low refractive index film is formed so that no bubbles remain, and the low refractive index film is formed. The spectrum of the surface reflectance of one side was measured with a visible ultraviolet spectrophotometer (manufactured by JASCO Corporation, trade name: V-570). The minimum surface reflectance at a wavelength of 400 to 800 nm of the glass substrate on which the low refractive index film was formed was 0.1%.

  Since the transmittance of the glass substrate was 91% and the surface reflectance was 4.5%, it was found that an antireflection film having excellent characteristics was formed and the transmittance was also improved.

<Evaluation of adhesion>
An adhesive tape with an adhesive strength of 320 cN / 25 mm and a width of 25 mm (Hitalex L-7330 manufactured by Hitachi Chemical Co., Ltd.) is used as the adhesive tape, and a roll laminator (LMP-350EX manufactured by Lamy Corporation) is used and the roll load is 0.3 MPa. An adhesive tape was attached to the low refractive index film under conditions of a speed of 0.3 m / min and a temperature of 20 ° C. One minute after the tape was brought into close contact, one end of the tape was lifted at a right angle to the substrate surface and peeled off instantaneously. As a result of visual observation of the low refractive index film, it was found that the low refractive index film was in close contact with the base material because the surface of the base material was not visible and the low refractive index film did not scatter visible light. The low refractive index films on the silicon substrate, glass substrate, and polystyrene were all in close contact with the base material.

  In addition, an adhesive tape of 360 cN / 25 mm (25 cN / 25 mm after UV irradiation) and 25 mm wide adhesive tape (BGP-101B manufactured by Electrochemical Co., Ltd.) was used as the adhesive tape, and a roll laminator (LMP-350EX manufactured by Lamy Corporation) was used. The pressure-sensitive adhesive tape was attached to the low refractive index film under the conditions of a roll load of 0.3 MPa, a feed rate of 0.3 m / min, and a temperature of 20 ° C. One minute after the tape was adhered, 200 mJ / cm 2 of ultraviolet light was irradiated using an ultraviolet exposure device (OMW Co., Ltd., HMW-6N-4), and one end of the tape was perpendicular to the substrate surface. Lifted and peeled off momentarily. The low refractive index films on the silicon substrate, glass substrate, and polystyrene were all in close contact with the base material.

Example 9
In accordance with Example 8, a base material on which an electrolyte polymer and fine particles were adsorbed was produced.

50 g of ethoxysilane oligomer (Colcoat Co., ethyl silicate 48) was placed in a 300 ml three-necked round bottom flask, 46 g of MeOH was added, and the mixture was stirred at 25 ° C. to make the solution uniform, and then H ₃ PO ₄ 10.0 wt%. 3.6 g of an aqueous solution was added and stirred at 25 ° C. for 24 hours to obtain a silicon compound solution having a silane concentration of 50%, and a silicon compound treatment solution was obtained by adjusting the silane concentration to 1% by weight. A low refractive index film was prepared according to Example 8.

  The refractive index of the low refractive index film evaluated in the same manner as in Example 8 was 1.25, the thickness was 110 nm, and the turbidity of the low refractive index film evaluated in the same manner as in Example 8 was 0.3%. . When the transmission spectrum of the glass substrate on which the low refractive index film was formed was measured in the same manner as in Example 8, the maximum transmittance at a wavelength of 400 to 800 nm was 95%. When the surface reflection spectrum of the glass substrate on which the low refractive index film was formed was measured in the same manner as in Example 8, the minimum surface reflectance at a wavelength of 400 to 800 nm was 0.1%.

  When the adhesion was evaluated in the same manner as in Example 8, the adhesive strength of 320 cN / 25 mm and the width of 25 mm adhesive tape (Hitalex L-7330 manufactured by Hitachi Chemical Co., Ltd.) was used on a silicon substrate, on a glass substrate, on polystyrene. The low refractive index films are all in close contact with the base material, and the adhesive strength is 360 cN / 25 mm (25 cN / 25 mm after UV irradiation) and the width of 25 mm is used for the adhesive tape (BGP-101B manufactured by Electrochemical Co., Ltd.). The low refractive index films on the silicon substrate, glass substrate, and polystyrene were all in close contact with the base material.

(Example 10)
In accordance with Example 8, a base material on which an electrolyte polymer and fine particles were adsorbed was produced.

Methoxysilane oligomer (Colcoat Co., Methyl Silicate 51) 50 g charged to a three neck round bottom flask 300ml was added to MeOH40g, after uniform stirring solution at 25 _℃, H ₃ PO 4 4.3% by weight 9.7 g of an aqueous solution was added and stirred at 25 ° C. for 4 hours to obtain a silicon compound solution having a silane concentration of 50%, and a silicon compound treatment solution was obtained by adjusting the silane concentration to 5% by weight. A low refractive index film was prepared according to Example 8.

  The refractive index of the low refractive index film evaluated in the same manner as in Example 8 was 1.25, the thickness was 110 nm, and the turbidity of the low refractive index film evaluated in the same manner as in Example 8 was 0.3%. . When the transmission spectrum of the glass substrate on which the low refractive index film was formed was measured in the same manner as in Example 8, the maximum transmittance at a wavelength of 400 to 800 nm was 95%. When the surface reflection spectrum of the glass substrate on which the low refractive index film was formed was measured in the same manner as in Example 8, the minimum surface reflectance at a wavelength of 400 to 800 nm was 0.1%.

  When the adhesion was evaluated in the same manner as in Example 8, the adhesive strength of 320 cN / 25 mm and the width of 25 mm adhesive tape (Hitalex L-7330 manufactured by Hitachi Chemical Co., Ltd.) was used on a silicon substrate, on a glass substrate, on polystyrene. The low refractive index films are all in close contact with the base material, and the adhesive strength is 360 cN / 25 mm (25 cN / 25 mm after UV irradiation) and the width of 25 mm is used for the adhesive tape (BGP-101B manufactured by Electrochemical Co., Ltd.). The low refractive index films on the silicon substrate, glass substrate, and polystyrene were all in close contact with the base material.

(Example 11)
In accordance with Example 8, a base material on which an electrolyte polymer and fine particles were adsorbed was produced.

  Except that an ethoxysilane oligomer (manufactured by Colcoat Co., ethyl silicate 48) was used as a silicon compound solution with a silane concentration of 100% and the silane concentration was adjusted to 1% by weight to obtain a silicon compound treatment solution, the same as in Example 8. A low refractive index film was prepared.

  The refractive index of the low refractive index film evaluated in the same manner as in Example 8 was 1.25, the thickness was 110 nm, and the turbidity of the low refractive index film evaluated in the same manner as in Example 8 was 0.3%. . When the transmission spectrum of the glass substrate on which the low refractive index film was formed was measured in the same manner as in Example 8, the maximum transmittance at a wavelength of 400 to 800 nm was 95%. When the surface reflection spectrum of the glass substrate on which the low refractive index film was formed was measured in the same manner as in Example 8, the minimum surface reflectance at a wavelength of 400 to 800 nm was 0.1%.

  When the adhesion was evaluated in the same manner as in Example 8, the adhesive strength of 320 cN / 25 mm and the width of 25 mm adhesive tape (Hitalex L-7330 manufactured by Hitachi Chemical Co., Ltd.) was used on a silicon substrate, on a glass substrate, on polystyrene. The low refractive index films are all in close contact with the base material, and the adhesive strength is 360 cN / 25 mm (25 cN / 25 mm after UV irradiation) and the width of 25 mm is used for the adhesive tape (BGP-101B manufactured by Electrochemical Co., Ltd.). The low refractive index films on the silicon substrate, glass substrate, and polystyrene were all in close contact with the base material.

(Example 12)
In accordance with Example 8, a base material on which an electrolyte polymer and fine particles were adsorbed was produced.

  Except that a methoxysilane oligomer (manufactured by Colcoat Co., Ltd., methyl silicate 51) was used as a silicon compound solution with a silane concentration of 100% and the silane concentration was adjusted to 5% by weight to obtain a silicon compound treatment solution, the same as in Example 8. A low refractive index film was prepared.

  The refractive index of the low refractive index film evaluated in the same manner as in Example 8 was 1.25, the thickness was 110 nm, and the turbidity of the low refractive index film evaluated in the same manner as in Example 8 was 0.3%. . When the transmission spectrum of the glass substrate on which the low refractive index film was formed was measured in the same manner as in Example 8, the maximum transmittance at a wavelength of 400 to 800 nm was 95%. When the surface reflection spectrum of the glass substrate on which the low refractive index film was formed was measured in the same manner as in Example 8, the minimum surface reflectance at a wavelength of 400 to 800 nm was 0.1%.

  When the adhesion was evaluated in the same manner as in Example 8, the adhesive strength of 320 cN / 25 mm and the width of 25 mm adhesive tape (Hitalex L-7330 manufactured by Hitachi Chemical Co., Ltd.) was used on a silicon substrate, on a glass substrate, on polystyrene. The low refractive index films are all in close contact with the base material, and the adhesive strength is 360 cN / 25 mm (25 cN / 25 mm after UV irradiation) and the width of 25 mm is used for the adhesive tape (BGP-101B manufactured by Electrochemical Co., Ltd.). The low refractive index films on the silicon substrate, glass substrate, and polystyrene were all in close contact with the base material.

(Example 13)
In accordance with Example 8, a base material on which an electrolyte polymer and fine particles were adsorbed was produced.

After putting 50 g of tetraethoxysilane (manufactured by Wako Pure Chemical Industries, Ltd., tetraethyl orthosilicate) into a 300 ml three-necked round bottom flask, adding 75 g of MeOH and stirring at 25 ° C. to make the solution uniform, H ₃ PO ₄ 1.3 After adding 17.7 g of a weight% aqueous solution and stirring at 25 ° C. for 24 hours, 50 g of an ethoxysilane oligomer (Colcoat Co., ethyl silicate 48) was added, stirred at 25 ° C. for 5 minutes, and silicon having a silane concentration of 70%. A compound solution was obtained.

  A low refractive index film was prepared in the same manner as in Example 8 except that the silicon compound treatment liquid was obtained by adjusting the silane concentration to 1% by weight.

  The refractive index of the low refractive index film evaluated in the same manner as in Example 8 was 1.25, the thickness was 110 nm, and the turbidity of the low refractive index film evaluated in the same manner as in Example 8 was 0.3%. . When the transmission spectrum of the glass substrate on which the low refractive index film was formed was measured in the same manner as in Example 8, the maximum transmittance at a wavelength of 400 to 800 nm was 95%. When the surface reflection spectrum of the glass substrate on which the low refractive index film was formed was measured in the same manner as in Example 8, the minimum surface reflectance at a wavelength of 400 to 800 nm was 0.1%.

  When the adhesion was evaluated in the same manner as in Example 8, the adhesive strength of 320 cN / 25 mm and the width of 25 mm adhesive tape (Hitalex L-7330 manufactured by Hitachi Chemical Co., Ltd.) was used on a silicon substrate, on a glass substrate, on polystyrene. The low refractive index films are all in close contact with the base material, and the adhesive strength is 360 cN / 25 mm (25 cN / 25 mm after UV irradiation) and the width of 25 mm is used for the adhesive tape (BGP-101B manufactured by Electrochemical Co., Ltd.). The low refractive index films on the silicon substrate, glass substrate, and polystyrene were all in close contact with the base material.

The measurement results of Examples 8 to 13 are shown in Table 2.

  As described above, adhesion of the substrate to the low refractive index film can be achieved by bringing either the alkoxysilane, the hydrolysis product of the alkoxysilane, the condensation reaction product of the hydrolysis product, or a mixture thereof into contact with the fine particle laminated film. It can be seen that

  In the method for producing a glass with an antireflection film of the present invention, a substrate with a porous film having excellent scratch resistance can be produced simply by subjecting a fine particle laminated thin film formed by an alternating lamination method to a silicate treatment using an oven or the like. Therefore, it is a manufacturing method of an antireflection film excellent in mass productivity.

It is the conceptual diagram which showed the mode of the coupling | bonding between microparticles | fine-particles accompanying application | coating of a silica sol. It is a schematic diagram which shows the state of the microparticles which continued in the shape of a bead, and the particle diameter of a primary particle. It is a graph which shows the relationship between the refractive index of an antireflection film, and the surface reflectance of a solid base material (refractive index 1.54) with an antireflection film.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base material 2 Electrolyte polymer 3 Fine particle 4 Void 5 Alcoholic silica sol product 10 Fine particle laminated thin film

Claims (3)

And a fine particle laminated thin film having voids provided on the substrate, wherein the fine particle laminated thin film alternately adsorbs the electrolyte polymer and the fine particles, and passes through the alcoholic silica sol product. A method for producing the substrate and the fine particles, and a substrate with a fine particle laminated thin film in which the fine particles and the fine particles are bonded , wherein the electrolyte polymer and the fine particles are alternately laminated on the substrate. Yes,
(A) a step of contacting or coating either the electrolyte polymer solution or the fine particle dispersion on the substrate surface;
(B) An electrolyte polymer solution or fine particle dispersion not used in the step A, wherein the electrolyte polymer solution or fine particle dispersion has a charge opposite to that of the electrolyte polymer solution or fine particle dispersion used in the step A. Contacting or applying,
(C) a step of contacting or applying an alcoholic silica sol solution having a solid content concentration of 0.1 wt% or more and less than 0.5 wt% as SiO ₂ concentration, and (D) a step of heat treatment at 20 ° C. to 140 ° C. The manufacturing method of the base material with a fine-particle laminated thin film provided with.   The method for producing a substrate with a fine particle laminated thin film according to claim 1, wherein the step C is performed after the step A and the step B are alternately performed once or more.   The manufacturing method of the base material with a fine particle laminated thin film of Claim 1 or 2 including the rinse process after the process selected from the said process A and the process B.

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