JP2007272156A - High refractive index cured film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide ultrafine particles having a high refractive index and excellent dispersibility, light resistance, weather resistance and transparency; a sol liquid containing the above ultrafine particles dispersed in water or an organic solvent; a coating liquid for forming a high refractive index cured film, the coating liquid containing the above sol and having excellent dispersion stability and coating adaptability; a high refractive index cured film showing preferable light resistance, weather resistance, transparency, scratch resistance, wear resistance, heat resistance, antistatic property and so on when the film is applied to a transparent substrate made of a resin, glass or the like; and an optical member comprising the above film. <P>SOLUTION: The coating liquid for forming a high refractive index cured film comprises: (1) coated oxide ultrafine particles comprising rutile type titanium oxide ultrafine particles having a refractive index of 1.5 to 2.8 as cores and coating layers made of silicon oxide applied to the cores by a specified method, or a sol liquid of the particles; (2) a curable binder component; and (3) water or an organic solvent. The present invention provides a high refractive index cured film formed by using the above coating liquid for forming a high refractive index cued film and an optical member comprising the cured film. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention is an ultrafine particle having a high refractive index, excellent dispersibility, light resistance, weather resistance, and transparency, a sol solution in which the ultrafine particle is dispersed in water or an organic solvent, and dispersion stability including the same, coating Light refractive index, weather resistance, transparency, scratch resistance, abrasion resistance when applied and cured on a coating solution for forming a high refractive index cured film with excellent suitability and a substrate such as resin or glass. The present invention relates to a cured film having good heat resistance and antistatic properties.
The present invention is particularly preferably a display surface such as a plasma display panel (PDP), a liquid crystal display (LCD), an electroluminescence display (ELD), or a cathode ray tube display (CRT), an eyeglass lens, a Fresnel lens, or a lenticular lens. Anti-reflection suitable for forming layers that constitute anti-reflective coatings covering the surfaces of various optical lenses such as microlens arrays such as CCDs and CCDs, camera lenses, etc., especially medium refractive index layers and / or high refractive index layers The present invention relates to a film-forming coating liquid, an antireflection film laminate, and an optical member comprising the same.

  Various image display devices such as plasma display panel (PDP), liquid crystal display device (LCD), electroluminescence display (ELD) and cathode ray tube display device (CRT), micro lenses such as eyeglass lenses, Fresnel lenses, lenticular lenses and CCDs A protective film (antireflection film) is usually provided on the surface of various optical lenses such as a lens array and a camera lens in order to prevent a decrease in contrast due to reflection of external light or reflection of an image. The antireflection film is designed so as to reduce the reflection in the visible light region as much as possible by producing a multilayer laminate of a plurality of thin films made of materials having different refractive indexes. Along with the sharpening of the display image, an antireflection film having good light resistance, weather resistance, transparency, scratch resistance, abrasion resistance, heat resistance, adhesion, antistatic property and the like is required.

  Further, an antistatic film having conductivity may be provided on the display surface. This is because dust, dust, or the like may adhere to the display surface and visibility may be reduced. In order to prevent this, the antistatic film is provided on the display surface together with the antireflection film, or provided as the high refractive index layer of the antireflection film, or only the antistatic film is provided on the display surface that does not require the antireflection film. Or provide. In addition, a transparent conductive film is incorporated as a transparent electrode in a liquid crystal display device or the like.

  In addition, an organic resin such as plastic may be used as the base material. Since these surfaces are soft and easily damaged, when the antireflection film or antistatic film described above is provided, a hard coat layer is first formed on the substrate, and then the antireflection film or antistatic film is provided thereon. Sometimes it is done. All of these require transparency.

  In general, an antireflection film is a multilayer of a plurality of thin films made of materials having different refractive indexes by using a metal oxide such as silicon oxide, titanium oxide, niobium oxide or the like by a dry treatment method such as vacuum deposition or chemical vapor deposition (CVD). Designs are made to produce a laminate and reduce reflection in the visible light region as much as possible. However, in such a dry coating process, the adhesion is poor, and problems such as peeling off of the antireflection layer may occur during the manufacturing process or use of the image display device. In addition, there are problems that the apparatus is expensive, the film formation rate is slow, and the productivity is not high so that it is not suitable for mass production. For this reason, the formation method by application | coating with high productivity is anticipated.

  Antireflection film with good light resistance, weather resistance, transparency, scratch resistance, abrasion resistance, heat resistance, adhesion, antistatic properties, etc. when applied to a substrate such as resin or glass A coating solution for forming an antireflective film that can form a film is desired.

  In recent years, a coating solution for forming an antireflective film, in which high refractive index fine particles are dispersed in a solution in which a binder component made of an organic substance is dissolved in order to form a high refractive index layer as described above, is applied onto a substrate and cured. A method for forming a cured film has been proposed.

  Since such a cured film needs to be transparent in the visible light region, it is necessary to use nano-order ultrafine particles having a primary particle diameter equal to or smaller than the wavelength of visible light as the high refractive index fine particles. Further, it is necessary to uniformly disperse the high refractive index ultrafine particles in the coating liquid for forming a cured film and in the cured film. In general, when an agglomerate of sub-micron order or more is included, the haze of the obtained coating film is deteriorated and the transparency is lowered. Therefore, in order to form a uniform cured film having a small haze, it is required to have sufficient dispersibility in the coating liquid for forming a cured film. It is also required to have sufficient dispersion stability so that it can be easily stored for a long period of time.

  When the antireflection film as described above is produced by a coating method, a binder resin is used as a matrix for film formation and holding. However, since the refractive index of this binder resin is usually 1.45 to 1.60, the refractive index of each layer is adjusted by the kind and amount of inorganic particles used. Particularly, in the antireflection film, inorganic fine particles having a refractive index of 1.9 or more are required. For this reason, it is extremely important to uniformly disperse ultrafine particles having a high refractive index in a matrix having a sufficient film strength.

  The high refractive index layer of such a coating type antireflection film includes a transparent single metal oxide having a high refractive index and a crystal structure such as Zr, Sn, Sb, Mo, In, Zn, Ti, etc. Are known. In addition, a technique for forming a high refractive index layer by introducing more high refractive index inorganic fine particles into a thin film while maintaining a dispersed state has been proposed.

  Furthermore, in order to improve the dispersibility of the ultrafine particles, the scratch resistance of the cured film, the surface hardness, the strength, and the like, a composite metal oxide composed of the metal element having a high refractive index as described above has been proposed.

  However, in the above technique, it has not been sufficient to design a cured film having a high refractive index while using an amount of binder capable of maintaining the strength of the film. This is because if the content of the fine particles is too large to increase the refractive index, the film becomes fragile and the adhesiveness also decreases. Further, when the refractive index of the high refractive index layer is not sufficiently high, the refractive index of the low refractive index layer is sufficient to reduce the minimum reflectance of the surface reflectance of the antireflection film to 1% or less. It is necessary to lower it.

  In order to further increase the refractive index, a method using titanium oxide particles, which are metal oxide particles having a high refractive index, has been proposed. Since titanium oxide has a particularly high refractive index and high transparency, it is particularly suitable for increasing the refractive index of optical thin films. However, a cured film composed of an organic binder component and titanium oxide fine particles has a drawback that its light resistance is lowered. In other words, the photocatalytic action of titanium oxide causes organic matter decomposition by electron-holes generated by light absorption, light resistance, weather resistance, transparency, scratch resistance, surface hardness, wear resistance, heat resistance, ultraviolet shielding properties. Etc. is a problem.

  Titanium oxide includes a rutile type and an anatase type as typical crystal types. So far, materials mainly composed of anatase-type titanium oxide ultrafine particles having a refractive index no = 2.56 and ne = 2.49 have been mainly used as high refractive index metal oxide ultrafine particle sol solutions. Yes. On the other hand, the refractive index of rutile-type titanium oxide has a refractive index no = 2.61, ne = 2.9 (no: refractive index for ordinary light, ne: refractive index for extraordinary light) (Chemical Society of Japan, Experimental Science) It is known that the optical properties such as high refractive index and ultraviolet absorption are superior to those of anatase type, and attempts to synthesize the rutile titanium oxide ultrafine particles and sol liquid are positive. It was done. However, the rutile type titanium oxide ultrafine particles and sol liquid that can be used industrially have not been obtained yet.

  At present, for the purpose of improving the light resistance of a resin composition containing anatase-type titanium oxide ultrafine particles, for example, ultrafine particles combining anatase-type titanium oxide and an inorganic oxide as described in Patent Document 1, or anatase-type titanium oxide Ultrafine particles coated with an inorganic oxide and a sol solution thereof are applied.

  All of these are aimed at inactivating the anatase-type titanium oxide ultrafine particles by coating with an inorganic oxide. Thus, light resistance is improved by coat | covering a titanium oxide ultrafine particle with an inorganic oxide. However, since the titanium oxide used is anatase type, the refractive index is about 2.5, and when coated with an oxide to improve light resistance, the refractive index is greatly reduced, The refractive index is lower than the original anatase-type titanium oxide, and the effect of improving the refractive index is low. Further, even if the amount of the metal oxide to be coated is reduced and the refractive index is increased, the light resistance is insufficient, and there are problems such as light resistance, weather resistance, transparency, scratch resistance and the like.

  On the other hand, the rutile type titanium oxide having a higher refractive index than the conventional anatase type titanium oxide, as described above, has no ultrafine particles and sol liquid that can be used.

  Moreover, it is necessary to disperse the titanium oxide ultrafine particles and the sol solution thereof in an organic solvent. However, since the titanium oxide ultrafine particle sol solution is usually stable in an acidic region and gelation and precipitation occur in a neutral to basic region, the usable pH region is limited. Or when it tries to disperse | distribute to an organic solvent, the problem on utilization that stability is easy to be impaired has arisen.

Therefore, the light resistance when applied to transparent substrates such as ultrafine particles, sol solution and resin or glass with high refractive index, excellent dispersibility, light resistance, weather resistance, and transparency, which solved such disadvantages. , Coating solution for forming a high refractive index cured film with good weather resistance, transparency, scratch resistance, surface hardness, abrasion resistance, heat resistance, adhesion, antistatic property, etc. High refractive index cured film with good light resistance, weather resistance, transparency, scratch resistance, abrasion resistance, heat resistance, antistatic property, etc. when applied and cured on a substrate, etc. An optical member is desired.
JP 2001-123115 A

  The object of the present invention has been achieved in view of the above-mentioned circumstances, and has a high refractive index and is excellent in transparency, dispersibility, light resistance, weather resistance, etc., and the ultrafine particles are dispersed in water or an organic solvent. And a coating solution for forming a high refractive index cured film containing the same and suitable for mass production and excellent in dispersion stability and coating suitability. In addition, light resistance, weather resistance, transparency, scratch resistance, surface hardness, abrasion resistance, heat resistance, adhesion, antistatic properties, etc. when applied to a transparent substrate such as resin or glass are good. The object is to obtain a cured film having a high refractive index and an optical member comprising the same. The present invention is particularly preferably a display surface such as a plasma display panel (PDP), a liquid crystal display (LCD), an electroluminescence display (ELD), or a cathode ray tube display (CRT), an eyeglass lens, a Fresnel lens, or a lenticular lens. Coating liquid for forming an antireflection film suitable for forming an antireflection film, particularly a medium to high refractive index layer, which covers the surface of various optical lenses such as a microlens array such as a CCD and a micro lens array and a camera lens The present invention relates to an antireflection film laminate and an optical member comprising the same.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that the tin compound used as a sintering agent prevents long fiber formation and also prevents aggregation. It has been found that a sol solution having excellent properties can be obtained. Furthermore, by forming this as a core ultrafine particle and providing a coating layer containing silicon oxide by a specific method, high refraction with excellent dispersibility, light resistance, weather resistance, and transparency that could not be obtained by conventional coating methods It was found that coated oxide ultrafine particles having an average particle diameter of 1 to 100 nm can be obtained. By combining the ultrafine particles with a binder component, a coating solution for forming a high refractive index cured film excellent in dispersion stability and coating suitability is obtained. When applied to a transparent substrate such as a resin or glass, light resistance, Discovered that a cured film having a high refractive index with good weather resistance, transparency, scratch resistance, abrasion resistance, heat resistance, antistatic property, etc. and an optical member comprising the same can be obtained, and completed the present invention. It came to do.

That is,
[1] (1) A coating layer (B) containing, as a nucleus (A), inorganic oxide ultrafine particles containing titanium oxide having a rutile crystal structure with a refractive index of 1.5 to 2.8, and containing silicon oxide Coated inorganic oxide ultrafine particles having an inorganic oxide coating layer or a sol thereof, (2) a curable binder component, and (3) water or an organic solvent for forming a high refractive index cured film Coating liquid.
[2] Rutile-type titanium oxide ultrafine particles in inorganic oxide ultrafine particles containing titanium oxide having a rutile-type crystal structure of the nucleus (A),
In the presence of a tin compound having a molar ratio of tin to titanium (Sn / Ti) of 0.001 to 2, a titanium compound aqueous solution having a Ti concentration of 0.07 to 5 mol / l is reacted in a pH range of −1 to 3. Obtained tin-modified rutile titanium oxide ultrafine particles having a Sn / Ti composition molar ratio of 0.001 to 0.5,
The coating layer containing silicon oxide (B) is of a two-layer coating type, the inner layer has a coating layer obtained by the step (1), and the outer layer is obtained by the step (2), The coating solution for forming a high refractive index cured film according to [1], which is a coated inorganic oxide ultrafine particle, wherein the weight ratio of the oxide coating layer is 0.001 to 20 in terms of SiO ₂ .
(1) Step of reacting silicon oxide having a weight ratio with respect to the nucleus (A) of 0.001 to 10 in terms of SiO ₂ with the nucleus (A) under the condition of pH <7 (2) with respect to the nucleus (A) The step of reacting the silicon oxide having a weight ratio of 0.001 to 10 in terms of SiO ₂ with the coated ultrafine particles obtained in (1) under the condition of pH ≧ 7 [3] The coated inorganic oxide super The coating liquid for forming a high refractive index cured film according to [1] or [2], wherein the minor axis and the major axis of the fine particles have a crystal axis of 2 to 20 nm.
[4] The coating for forming a high refractive index cured film according to any one of [1] to [3], wherein an average aggregate particle diameter of the aggregate crystals composed of the coated inorganic oxide ultrafine particles is 10 to 100 nm. liquid.
[5] The high refractive index cured film formation according to any one of [1] to [4], wherein the coated inorganic oxide ultrafine particles are a sol liquid dispersed in water or an organic solvent. Coating liquid.
[6] The high refractive index according to any one of [1] to [5], wherein the surface of the coated inorganic oxide ultrafine particles is surface-treated with an organosilane compound and / or an amine. Coating liquid for forming a cured film.
[7] The curable binder component of (2) is at least one of a photocurable and / or thermosetting organic monomer or oligomer, a resin, and an organometallic compound and / or a partial hydrolyzate thereof [1] ] The coating liquid for high refractive index cured film formation in any one of [6].
[8] A cured film formed by applying and curing the coating solution for forming a high refractive index cured film according to any one of [1] to [7].
[9] An antireflection film using the coating liquid for forming a high refractive index cured film according to any one of [1] to [7] or the cured film according to [8].
[10] An antireflection film formed by laminating two or more thin films having different refractive indexes, at least one of which is a coating for forming a high refractive index cured film according to any one of [1] to [7] The antireflection film according to [9], wherein the layer is a layer using the liquid or the cured film according to [8], and the layer is a medium to high refractive index layer.
[11] On at least one surface of the substrate, a high refractive index layer / low refractive index layer, a hard coat layer / high refractive index layer / low refractive index layer, or a hard coat layer / medium refractive index layer / high refractive index layer. / An antireflection laminate having a multilayer structure in which low refractive index layers are sequentially laminated, wherein the high refractive index layer and the middle refractive index layer are any one of [1] to [7] An antireflection laminate, which is a layer using a coating liquid for forming a cured film or the cured film according to [8].
[12] An optical member provided with the antireflection film according to [10] or the antireflection laminate according to [11].
It is about.

  The tin-modified rutile type titanium oxide ultrafine particles of the present invention can be provided as ultrafine particles and sol liquid having a high refractive index that cannot be obtained by the conventional production method and that cannot be obtained by the anatase type. By providing this tin-modified rutile-type titanium oxide ultrafine particle with a specific method and a coating layer containing silicon oxide, it has excellent dispersibility, light resistance, weather resistance, and transparency that could not be obtained by conventional coating methods. It is possible to provide ultrafine particles having an average particle diameter of refractive index of 1 to 100 nm. Furthermore, when this is applied to a coating solution for forming a high refractive index cured film, it has a high refractive index excellent in light resistance, weather resistance, transparency, scratch resistance, abrasion resistance, heat resistance, antistatic property, etc. It is possible to obtain a cured film of the above and an optical member comprising the same.

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

  The coating solution for forming a high refractive index cured film according to the present invention comprises (1) a rutile type titanium oxide ultrafine particle having a refractive index of 1.5 to 2.8 as a core particle, and the core particle and a silicon oxide. A coating-type inorganic oxide ultrafine particle composed of a coating layer or a sol thereof, (2) a curable binder component, and (3) a coating solution for forming a high refractive index cured film, comprising water or an organic solvent. .

That is,
(1) An inorganic oxide ultrafine particle containing titanium oxide having a rutile crystal structure with a refractive index of 1.5 to 2.8 is used as a nucleus (A), and is composed of a coating layer (B) containing silicon oxide. Coated inorganic oxide ultrafine particles having an inorganic oxide coating layer or sol thereof, (2) a curable binder component, and (3) a coating solution for forming a high refractive index cured film comprising water or an organic solvent, Because
The rutile type titanium oxide ultrafine particles in the inorganic oxide ultrafine particles containing titanium oxide having the rutile type crystal structure of the nucleus (A),
In the presence of a tin compound having a molar ratio of tin to titanium (Sn / Ti) of 0.001 to 2, a titanium compound aqueous solution having a Ti concentration of 0.07 to 5 mol / l is reacted in a pH range of −1 to 3. Obtained tin-modified rutile titanium oxide ultrafine particles having a Sn / Ti composition molar ratio of 0.001 to 0.5,
The coating layer containing silicon oxide (B) is of a two-layer coating type, the inner layer has a coating layer obtained by the step (1), and the outer layer is obtained by the step (2), A coating solution for forming a high refractive index cured film, which is a coated inorganic oxide ultrafine particle, wherein the weight ratio of the oxide coating layer is 0.001 to 20 in terms of SiO ₂ .
(1) Step of reacting silicon oxide having a weight ratio with respect to the nucleus (A) of 0.001 to 10 in terms of SiO ₂ with the nucleus (A) under the condition of pH <7 (2) with respect to the nucleus (A) The step of reacting the silicon oxide having a weight ratio of 0.001 to 10 in terms of SiO ₂ with the coated ultrafine particles obtained in (1) under the condition of pH ≧ 7

  (1) A coated inorganic oxide comprising a rutile-type titanium oxide ultrafine particle having a refractive index of 1.5 to 2.8 of the present invention as a core fine particle and comprising a coating layer containing the core fine particle and silicon oxide Ultrafine particles can have a higher refractive index than when anatase-type titanium oxide is used, and thus a cured film having a high refractive index can be formed.

  In the present invention, the inorganic oxide ultrafine particles containing titanium oxide having a rutile-type crystal structure, as long as it contains rutile-type titanium oxide formed into ultrafine particles as described above, the rutile-type crystal structure Even if it is a complex with a titanium oxide having a rutile crystal structure, it may be a shape that covers a titanium oxide having a rutile type crystal structure, and is not particularly limited. The ratio of rutile type titanium oxide is 5 to 100% (weight ratio), preferably 50 to 100%, and more preferably 70 to 100%.

  Further, the components other than the ultrafine particles of rutile titanium oxide are not particularly limited as long as they do not impair the dispersion stability of the ultrafine particles of the present invention. Among them, inorganic oxides are desirable. Specific examples include oxides such as Al, Si, V, Fe, Zn, Zr, Nb, Mo, Sn, Sb, and W, and preferably oxidation of Al, Si, Zr, Sn, and Sb. It is a thing.

  In the present invention, a preferable rutile type titanium oxide ultrafine particle is a core fine particle, and the coated inorganic oxide ultrafine particle composed of a coating layer containing the core fine particle and silicon oxide is more specifically, rutile. Type titanium oxide ultrafine particles, in the presence of a tin compound having a molar ratio of tin to titanium (Sn / Ti) of 0.001 to 2, a titanium compound aqueous solution having a Ti concentration of 0.07 to 5 mol / l has a pH of −1 to 1. Tin-modified rutile-type titanium oxide ultrafine particles obtained by reacting in the range of 3, the Sn / Ti composition molar ratio of the ultrafine particles being 0.001 to 0.5, and the short axis and long of the crystal diameter Tin-modified rutile titanium oxide ultrafine particles characterized in that the axis is 2 to 20 nm and the average aggregate particle diameter of the ultrafine particle aggregate crystals is 10 to 100 nm are used as the core fine particles. Is a coating-type inorganic oxide ultrafine particles composed of uncoated layer.

  The crystal diameter referred to here is a so-called primary particle diameter, and is expressed by the lengths in the a and c axis directions as described in Chemical Handbook Revision 3 (Basic Edition Maruzen Co., Ltd.). In this specification, they are called a short axis and a long axis, respectively. Moreover, the average aggregated particle diameter represents a particle diameter obtained by aggregating primary particles.

  First, a method for producing tin-modified rutile titanium oxide ultrafine particles will be described.

  The tin compound used in the present invention is not particularly limited, but specifically, for example, a tin salt compound such as tin chloride, tin nitrate, tin sulfate, stannate, or an oxide, hydroxide, metal Preferred examples include tin compounds selected from tin and the like.

  The titanium compound used in the present invention is not particularly limited. Specifically, for example, titanium chloride oxide, titanium sulfate, titanium nitrate, titanium alkoxide, hydrated titanium oxide (a titanium compound in advance under alkaline conditions). Preferred examples include titanium compounds selected from such as hydrolyzed ones).

  First, a tin compound is added to an aqueous solution, and a titanium compound is added thereto. The tin compound and the titanium compound may be added at the same time, or either one may be first. Moreover, the form of a mixed compound may be sufficient. The reaction medium is preferably water, but may be an organic solvent such as alcohol or a mixed solvent of water and an organic solvent.

  The amount of tin compound used in the reaction as a modifier for controlling crystal growth of rutile titanium oxide is such that the molar ratio of tin to titanium (Sn / Ti) is 0.001 to 2, preferably 0.01 to 1. It is desirable. If the tin amount is less than the above range, rutile-type titanium oxide ultrafine particles are produced, but the crystal diameter and aggregated particle diameter are increased, and therefore the dispersibility may be deteriorated. Moreover, the transparency of a cured film may fall. Further, even if the amount is larger than the above range, it is possible to synthesize the titanium oxide ultrafine particles having the rutile type, but the time required for the reaction becomes long. In this case, a large amount of tin compound is contained in the rutile type titanium oxide ultrafine particles. There is a possibility that a product with attached will be obtained. On the other hand, if it is larger than this, the amount of the residual tin compound increases, and the particle refractive index may decrease.

  The Ti concentration in the reaction solution is 0.07 to 5 mol / l, preferably 0.1 to 1 mol / l. When the Ti concentration is lower than the above range, there is a possibility that anatase-type and rutile-type mixed titanium oxide ultrafine particles may be produced even if a tin compound is added in the range of 0.01 to 0.03 as Sn / Ti (molar ratio). is there. Similarly, at a Ti concentration lower than the above range, if a tin compound is added in a range larger than 0.03 as Sn / Ti (molar ratio), there is a possibility that titanium oxide-tin oxide mixed ultrafine particles having rutile tin oxide are generated. is there.

  The pH of the reaction solution is desirably −1 to 3. Adjust with hydrochloric acid or nitric acid as necessary. When the reaction is carried out under a condition where the pH is greater than 3, anatase-type titanium oxide is obtained in the case where no tin compound is added, and in order to avoid this, a tin compound is added to obtain a rutile structure. There is a possibility that foreign substances other than rutile-type titanium oxide are produced.

  Regarding the reaction temperature, the Ti concentration and pH may be in the above ranges, and there is no particular limitation, but preferably −10 to 100 ° C., more preferably 20 to 60 ° C. is recommended. Although the reaction completion time is determined depending on the reaction temperature, it is usually carried out in 0.5 to 10 hours.

  The amount of tin compound contained in the tin-modified rutile-type titanium oxide ultrafine particles produced by the above reaction is preferably Sn / Ti molar ratio = 0.001 to 0.5. If the amount of tin is made smaller than the above range, the particle diameter of the rutile titanium oxide ultrafine particles becomes large and the dispersibility may be deteriorated. Also, if the amount is larger than the above range, crystal growth and aggregation can be controlled more efficiently, and ultrafine particles with a small particle diameter can be obtained, but a rutin-type titanium oxide ultrafine particle with a large amount of tin compound attached can be obtained. As a result, ultrafine particles having a low refractive index may be obtained.

  The minor axis and major axis of the tin-modified rutile-type titanium oxide ultrafine particles obtained by this method have a minor axis and a major axis of 2 to 20 nm, and an average aggregated particle diameter of 10 to 100 nm.

  Although the reaction mechanism (reaction mechanism) by which the tin-modified rutile-type titanium oxide ultrafine particles of the present invention are obtained is not sufficiently clear at present, this is characterized in that the surface is modified with a tin compound. It is presumed that the tin compound used as the raw material, the tin ion dissociated in the solution, or the tin compound generated in the solution by hydrolysis or the like adhered to the titanium oxide surface by coordination, adsorption, chemical bonding, or the like. In addition, it is presumed that the tin compound was originally added as a modifier under the conditions for producing rutile type titanium oxide instead of the anatase type, and this was caused as a result of the inhibition of crystal growth in the major axis direction. This indicates that the amount of the modified tin compound necessary for obtaining tin-modified titanium oxide ultrafine particles having a crystal diameter of 2 to 20 nm is far from the amount of titanium oxide coated without a gap, and the molar ratio to titanium is 0. It can be seen from the small amount of 001-0.5.

  The reaction product obtained as described above may be used as tin-modified rutile-type titanium oxide ultrafine particles or sol liquid as it is, or may be subjected to a desired post-treatment. That is, it can be purified by a known method such as vacuum concentration using an evaporator or ultrafiltration, and concentrated to an appropriate concentration. Centrifugation can yield a white precipitate that can be redispersed in water or other desired organic solvents.

  It is preferable that the minor axis and the major axis of the tin-modified rutile-type titanium oxide ultrafine particles obtained by the present invention are 2 to 20 nm and the average aggregate particle diameter is 10 to 100 nm. If the crystal diameter is smaller than 2 nm, the scratch resistance and hardness are insufficient when a cured film is prepared using a coating solution containing these, and the originally obtained refractive index may not be obtained. If it is larger than 20 nm, light scattering may occur. If the average aggregate particle diameter is larger than 100 nm, the resulting film may become cloudy and opaque.

  Next, a method for preparing the coating layer (B) containing silicon oxide will be described.

The coating layer (B), that is, the coating layer containing silicon oxide, is a two-layer coating type, in which the inner layer is obtained by the step (1) and the outer layer is obtained by the step (2). The weight ratio of the material coating layer is 0.001 to 20 in terms of SiO ₂ .
(1) Step of reacting silicon oxide having a weight ratio with respect to the nucleus (A) of 0.001 to 10 in terms of SiO ₂ with the nucleus (A) under the condition of pH <7 (2) with respect to the nucleus (A) The step of reacting the silicon oxide having a weight ratio of 0.001 to 10 in terms of SiO ₂ with the coated ultrafine particles obtained in (1) under the condition of pH ≧ 7

  In the present invention, when the tin-modified rutile-type titanium oxide ultrafine particles synthesized as described above or a sol solution thereof is used as an antireflection film-forming coating solution or antireflection film, in order to prevent deterioration of surrounding organic substances due to the photocatalytic property of titanium oxide. It is necessary to impart light resistance. For this purpose, tin-modified rutile titanium oxide ultrafine particles are coated with a coating layer containing silicon oxide. In addition, a coating means both the form which covered the fine particle surface completely, or the form with which the clearance gap was opened.

  Examples of the silicon oxide used for the coating include silicates such as colloidal silica, silicate sol, sodium silicate, or potassium silicate. The silicon oxide here may be an amorphous oxide, a crystalline oxide, or a hydrated state. Further, it may be silicic acid, silicic acid oligomer, or a salt thereof, and may be in a state in which they are adsorbed and bound to the surface of the nuclear fine particles.

  As a method for forming the coating layer, first, a sol solution of tin-modified rutile-type titanium oxide ultrafine particles is prepared. It is desirable to dilute or concentrate the sol solution prepared above so that the solid content is in the range of 0.01 to 20% by weight, preferably 0.1 to 5% by weight. When the solid content concentration of the sol liquid is less than 0.01% by weight, the productivity is low and not industrially effective, and when the solid content concentration of the sol liquid exceeds 20% by weight, the resulting ultrafine particles may become aggregates. There is sex.

  A solution in which silicon oxide is dissolved in water and / or an organic solvent is continuously or intermittently added to a reaction liquid containing nuclear fine particles (in this case, tin-modified rutile-type titanium oxide ultrafine particles which are nuclei (A)). Add to react on the surface of the core particle. It is desirable to drop over 0.1 to 100 hours (to the extent that the core fine particle sol solution does not gel). The concentration after the completion of dropping of the silicon oxide in the reaction solution is preferably 0.01 to 5 wt% in terms of silicon oxide. If it is smaller than this, the productivity is low and it is not industrially effective, and if it is larger than this, polymerization may proceed too much and an insoluble substance of silicon oxide may be formed.

[Step (1): A step of reacting a silicon oxide having a weight ratio with respect to the nucleus (A) of 0.001 to 10 in terms of SiO ₂ with the nucleus (A) under the condition of pH <7.
First, the core fine particles, that is, the core (A) and the silicon oxide having a weight ratio with respect to the core (A) of 0.001 to 10 in terms of SiO ₂ are reacted under the condition of pH <7.

Although there is no restriction | limiting in particular as a silicon oxide used here, Colloidal silica and silicate sol are preferable. The amount to be used, the weight ratio of the nucleus (A) is 0.001 to 10 is preferable in terms of SiO ₂ is preferably 0.01 to 0.5. If it is in this range, that is, greater than 10, a sufficient refractive index may not be obtained. If it is less than this range, that is, 0.001, dispersion stability may be lowered.

  The pH of the reaction solution is preferably less than 7, and more preferably 2-4. If the pH is 7 or more, tin-modified rutile titanium oxide ultrafine particles, which are core fine particles, may cause aggregation and gelation. Further, if the pH is too lower than 1, the electric double layer of the nuclear fine particles is shielded by excess positive ions, which may cause aggregation. You may adjust pH by adding an acidic compound or a basic compound as needed. Examples of acidic compounds include hydrochloric acid, sulfuric acid, and nitric acid, and basic compounds include sodium hydroxide and potassium hydroxide.

  In this step, a solution in which silicon oxide is dissolved in water and / or an organic solvent is continuously or intermittently added to the reaction liquid containing the nuclear fine particles to react on the surface of the fine nuclear particles. It is desirable to drop the sol solution so that the core fine particle sol solution does not gel over 0.1 to 100 hours. Longer than this is not economically efficient. If it is shorter than this, the reaction may be insufficient.

  Although reaction temperature does not have a restriction | limiting in particular, 0-200 degreeC is preferable and 30-100 degreeC is more preferable. If it is in this range, that is, higher than 200 ° C., ultrafine particles may be aggregated. If it is less than this range, that is, 0 ° C., the reaction may not proceed sufficiently.

[Step (2): The silicon oxide having a weight ratio with respect to the nucleus (A) of 0.001 to 10 in terms of SiO ₂ is reacted with the coated ultrafine particles obtained in (1) under the condition of pH ≧ 7. Process]
The coated ultrafine particles or sol solution obtained in the step (1) is dissolved as necessary. Subsequently, the weight ratio of the coated ultrafine particles obtained in (1) to the nucleus (A) is calculated in terms of SiO ₂ . The silicon oxide which becomes 0.001 to 10 is reacted under the condition of pH ≧ 7.

Although there is no restriction | limiting in particular as a silicon oxide used here, Colloidal silica and silicate sol are preferable. The amount to be used, the weight ratio of the nucleus (A) is 0.001 to 10 is preferable in terms of SiO ₂ is preferably 0.1 to 1. If it is in this range, that is, greater than 10, a sufficient refractive index may not be obtained. If this range is smaller than 0.001, sufficient light resistance may not be obtained.

  The pH of the reaction solution is preferably 7 or more, more preferably 8-11. What is necessary is just to adjust pH to this range suitably. If the pH is less than 7, a dense coating layer may not be formed. The pH may be adjusted appropriately by adding a basic compound. Examples of the basic compound include sodium hydroxide and potassium hydroxide.

  In this step, a solution in which silicon oxide is dissolved in water and / or an organic solvent is continuously or intermittently added to the reaction liquid containing the nuclear fine particles to react on the surface of the fine nuclear particles. It is desirable to add over 0.1 to 100 hours. Longer than this is not economically efficient. If it is shorter than this, the reaction may be insufficient.

  Although reaction temperature does not have a restriction | limiting in particular, 0-200 degreeC is preferable and 80-200 degreeC is more preferable. If it is in this range, that is, higher than 200 ° C., fine particles may aggregate. If it is less than this range, that is, 0 ° C., the reaction may not proceed sufficiently.

  Other inorganic oxides contained in the coating layer (B), that is, the coating layer containing silicon oxide, are not particularly limited as long as they do not impair the light resistance, dispersibility, and storage stability of the resulting fine particles. However, specific examples include oxides such as Al, Si, V, Fe, Zn, Zr, Nb, Mo, Sn, Sb, and W, and preferably Al, Si, Zr, Sn, and Sb. The oxide of this is mentioned.

  Moreover, as the coating layer, only the coating layer made of the two-layered silicon oxide described above is desirable, but another inorganic oxide coating layer may be provided. In this case, it is desirable to provide inside the coating layer made of the two-layered silicon oxide described above.

  The coated inorganic oxide ultrafine particles obtained by the present invention, that is, the minor axis of the crystal diameter of the double-layered silicon oxide-coated tin-modified rutile titanium oxide ultrafine particles, the major axis is 2 to 20 nm, and the average aggregated particle diameter is 10 to 10. 100 nm is preferable. If the crystal diameter is smaller than 2 nm, the originally obtained refractive index may not be obtained. If it is larger than 20 nm, light scattering may occur. If the average aggregate particle size is larger than 100 nm, the sol solution may become cloudy and the cured film may become opaque.

  The weight ratio of the silicon oxide coating layer to the core fine particles obtained by the above method is 0.001 to 20 in terms of SiO2. The refractive index and light resistance of the ultrafine particles themselves can be adjusted by the amount of the coating layer. Thereby, the desired light resistance can be imparted and the refractive index can be adjusted to 1.5 to 2.8.

  The reaction product obtained as described above may be used as it is as a coated inorganic oxide ultrafine particle, that is, a two-layer silicon oxide-coated tin-modified rutile titanium oxide ultrafine particle sol solution, or may be subjected to a desired post-treatment. Also good. That is, it can be purified by a known method such as vacuum concentration using an evaporator or ultrafiltration, and concentrated to an appropriate concentration. Centrifugation can yield a white precipitate that can be redispersed in water or other desired organic solvents. In particular, by performing ultrafiltration, it is possible to remove the ion component that causes the aggregation of the fine particles by shielding the electric double layer around the fine particles, so that the dispersion stability is improved.

  Titanium oxide ultrafine particles usually have an equipotential point in the neutral region, and in the conventional production method, they are sol solutions that are stable in the acidic region. For this reason, the titanium oxide ultrafine particle sol solution produced by the conventional method has a problem that the neutral to basic flocculation causes aggregation and gelation, and the range of use is limited. Moreover, when it tried to substitute with an organic solvent, there existed a problem of causing aggregation and gelatinization and impairing stability. Furthermore, even when the dispersion medium is water, if it is concentrated to 10% by weight or more, gelation is caused, and it is difficult to obtain a sol solution dispersed at a high concentration, resulting in low productivity. By reacting the silicon oxide according to the present invention in the range of pH <7, there is no aggregation or gelation in a wide range of pH, particularly 14> pH> 3, and it is a thin film excellent in dispersibility and storage stability. A titanium oxide ultrafine particle sol solution coated with a silicon oxide layer can be obtained, and a dense and thick silicon oxide coating layer can be provided by reacting in a range of pH ≧ 7.

  In general, the surface of a titanium oxide ultrafine particle sol that is stable in an acidic region is positively charged. By reacting there under the above conditions, by selecting ultrafine particles having the opposite sign charge and smaller in size than the nuclear fine particles, heteroaggregation is caused on the surface of the nuclear fine particles, and the thin layer is more effectively and uniformly formed. It is considered that a silicon oxide film is formed, thereby imparting SiO2 characteristics to the surface of the core fine particle, and the titanium oxide ultrafine particle sol according to the present invention is stable in a wide pH range of pH = 3-14. By growing a dense and thick silicon oxide layer under basic conditions of pH ≧ 7, ultrafine particles having light resistance and weather resistance can be obtained while maintaining high dispersibility. That is, ultrafine titanium oxide particles having a two-layer structure of a coating inner layer formed at pH <7 and a coating outer layer formed at pH ≧ 7 and excellent in transparency, dispersibility, storage stability, light resistance, weather resistance, etc. A sol solution.

  Due to the silicon oxide coating, the concentration of the sol solution is stably present in a wide range of pH even when the concentration is as high as 20% by weight or more, further 35% by weight or more in terms of solid content.

  The surface of the coated inorganic oxide ultrafine particles obtained by the present invention, that is, the two-layer silicon oxide-coated tin-modified rutile titanium oxide ultrafine particles is preferably treated with an organosilicon oxide or an amine. This greatly improves long-term dispersion stability of the ultrafine particles in the coating solution for forming a cured film containing the ultrafine particles and the curable binder component. In particular, when an organic solvent having a relative dielectric constant smaller than that of methanol is used, it is preferable to improve the affinity with the solvent by surface treatment. This improves the transparency, scratch resistance, hardness, wear resistance, etc. of the cured film. Here, the surface treatment may be any of those chemically bonded to the surface, chemical adsorption, physical adsorption and the like.

  When surface-treating with an organosilicon compound, a compound known as a silane coupling agent is suitable. Specifically, organosilicon compounds represented by the following general formulas (1) and (2) are preferable.

(R ¹ ) _a (R ² ) _b Si (OR ³ ) _(3-ab) (1)
Si (OR ³ ) ₄ (2)
(Wherein R ¹ and R ² are organic groups having an alkyl group, a halogenated alkyl group, a vinyl group, an allyl group, an acyl group, an acryloxy group, a methacryloxy group, a mercapto group, an amino group, an epoxy group, etc. (It is bonded to silicon by a —C bond. R ³ is an organic group such as an alkyl group having 1 to 8 carbon atoms, an alkoxyalkyl group, or an acyl group.)

Specific examples of R ¹ , R ² and R ^{3 in the} general formulas (1) and (2) include, for example, an organic group having an alkyl group such as a methyl group, an ethyl group, a propyl group, The organic group having a group is a chloromethyl group, a 3-chloropropyl group, etc., the organic group having an acyl group is an acetoxypropyl group, etc., and the organic group having an acryloxy group is a 3-acryloxypropyl group As the organic group having a methacryloxy group, a methacryloxypropyl group or the like is used. As the organic group having a mercapto group, a mercaptomethyl group is used. As the organic group having an amino group, a 3-aminopropyl group is used. The organic group containing an epoxy group is a 3-glycidoxypropyl group or the like, and the alkoxyalkyl group is a methoxyethyl group or the like. Can be mentioned.

  Specific examples of the compound represented by the general formula (1) include methyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, allyldimethoxysilane, allyltriethoxysilane, acetoxypropyltrimethoxysilane, 3-acryloxypropyldimethylmethoxysilane, methacryloxymethyltriethoxysilane, methacryloxypropylmethyldiethoxysilane, methacryloxypropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-amino Propyltrimethoxysilane, (3-glycidoxypropyl) dimethylethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, (3-glycidoxypropyl) trimethoxy Orchids, etc. trimethyl methoxy silane.

  Specific examples of the compound represented by the general formula (2) include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetra-n-propoxysilane, tetra-n-butoxysilane, and tetra-tert. -Butoxysilane, tetra-sec-butoxysilane and the like.

  Hydrolysis of the organosilicon compound represented by the general formula is carried out by adding hydrochloric acid or the like. Thereby, a part or all of the alkoxy group is hydrolyzed. Alcohols such as methanol, cellosolves such as methyl cellosolve, esters such as ethyl acetate, ethers such as tetrahydrofuran, ketones such as acetone, halogen hydrocarbons such as chloroform, hydrocarbons such as toluene and heptane, etc. Dilution may be performed.

  These may be reacted without hydrolysis, or after hydrolysis, the hydrolyzate, partial hydrolyzate, or partial condensate may be reacted with ultrafine particles. Furthermore, it may be reacted with a silicone resin such as polysiloxane having a hydrolyzable group or a hydroxyl group in a condensed form thereof. These may be used alone or as a mixture.

After the (OR ³ ) group is hydrolyzed, it is preferable to cause a dehydration reaction with the —OH group on the surface of the ultrafine particles to form a Si—O—M bond, but a part thereof may remain.

  As a treatment method, a sol solution is mixed with a solvent containing an organosilicon oxide, and a catalyst is added if necessary, followed by heating for a certain time. If necessary, it is performed by a method such as removing unreacted components in the mixed solution by a method such as ultrafiltration or centrifugation.

  As the amine (s) used for the surface treatment, propylamine, diisopropylamine, butylamine, triethylamine, dodecylamine, and the like are preferably used. In order to perform surface treatment with these, for example, ultrafine particles or a sol solution is mixed in a solution such as water or alcohol, and after adding a catalyst as necessary, it is left at room temperature for a predetermined time or is subjected to heat treatment. Good.

  A polymer having the above functional group is also effective. For example, styrene resin which is amination of polystyrene, and derivatives thereof, a polymer having a hydrolyzable silicon group in the side chain of polymethyl methacrylate, a silicone resin having a hydrolyzable group or a hydroxyl group, and the like can be mentioned. The surface treatment method may be performed by the method described above.

  The amount of the surface treatment agent used is appropriately set in consideration of the dispersion medium used and the dispersibility in the coating solution.

  Further, since the surface of the titanium oxide ultrafine particles easily reacts with carboxylic acid, acetic acid, propionic acid, acrylic acid, methacrylic acid, tartaric acid, glycolic acid, polyacrylic acid, and the like can be used. It is appropriately set in consideration of the silicon oxide coating layer.

  By this method, silicon oxide-coated tin-modified rutile titanium oxide ultrafine particles having a minor axis and a major axis of 2 to 20 nm and an average aggregated particle diameter of 10 to 100 nm are obtained. If the crystal diameter is smaller than 2 nm, there is a possibility that the refractive index originally obtained when used for a cured film containing these may not be obtained. If it is larger than 20 nm, light scattering may occur. If the average aggregate particle size is larger than 100 nm, the sol solution, the cured film, etc. may become cloudy and become opaque.

  The organic solvent (dispersion medium) used to disperse the ultrafine particles in the present invention is not particularly limited. Specifically, for example, alcohols such as methanol, ethanol, isopropanol, methyl cellosolve, ethyl cellosolve, propylene glycol monomethyl Glycol ethers such as ether, esters such as ethyl acetate, ethers such as tetrahydrofuran, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, halogen hydrocarbons such as chloroform, hydrocarbons such as toluene and heptane, etc. An organic solvent is mentioned, You may mix and use 2 or more types. In either case, a method of replacing the dispersion medium with an evaporator or the like is employed.

  Next, (2) the curable binder component of the present invention will be described.

  The (2) curable binder component used in the present invention is not particularly limited, and among them, photocurable and / or thermosetting organic monomers or oligomers, organometallic compounds and / or parts thereof. Hydrolysates and / or organic polymers are preferred.

  In the present invention, in order to impart sufficient scratch resistance, hardness, strength, and adhesion to the cured film, the cured film forming coating liquid according to the present invention is applied to the surface of the substrate, and dried as necessary. After that, a binder component that is polymerized, preferably crosslinked and cured by some chemical reaction is preferable, and an organic monomer or oligomer having light or thermosetting property, an organic metal compound, and / or a partial hydrolyzate thereof are preferable.

  Furthermore, as the photo-curable binder, a monomer or oligomer that undergoes a polymerization reaction directly or upon irradiation with ionizing radiation such as ultraviolet light or electron beam can be used. A monomer or oligomer having a methacryl group is preferred. Among them, a polyfunctional binder component is preferable in order to increase the scratch resistance and hardness by crosslinking.

  Specific examples of compounds having one functional group in one molecule include isoamyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, butoxyethyl (meth) acrylate, ethoxydiethylene glycol (meta ) Acrylate, methoxy-triethylene glycol (meth) acrylate, methoxy-polyethylene glycol (meth) acrylate, methoxydipropylene glycol (meth) acrylate, methoxydiethylene glycol (meth) acrylate phenoxyethyl (meth) acrylate, phenoxy polyethylene glycol (meth) Acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2- Droxypropyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, (meth) acrylic acid, 2- (meth) acryloyloxyethyl-succinic acid, 2- (meth) acryloyloxyethylphthalic acid , Isooctyl (meth) acrylate, isomyristyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, cyclohexyl Methacrylate, benzyl (meth) acrylate, (meth) acryloylmorpholine and the like can be mentioned.

  Specifically, those having two or more functional groups include, for example, polyethylene glycol diacrylate, glycerin triacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, diester Examples thereof include pentaerythritol hexaacrylate, alkyl-modified dipentaerythritol pentaerythritol, and the compounds having a benzene ring include ethylene oxide-modified bisphenol A diacrylate, modified bisphenol A diacrylate ethylene glycol diacrylate, ethylene oxide propylene oxide modified bisphenol. A diacrylate, propylene oxide tetramethylene oxide Modified bisphenol A diacrylate, bisphenol A- diepoxy - acrylic acid adduct, ethylene oxide-modified bisphenol F diacrylate, and polyfunctional acrylates or methacrylates such as polyester acrylates.

  1,2-bis (meth) acryloylthioethane, 1,3-bis (meth) acryloylthiopropane, 1,4-bis (meth) acryloylthiobutane, 1,2-bis (meth) acryloylmethylthiobenzene, The use of sulfur-containing (meth) acrylates such as 1,3-bis (meth) acryloylmethylthiobenzene is also effective for increasing the refractive index.

  Moreover, in order to accelerate | stimulate hardening by an ultraviolet-ray or a heat | fever, you may mix | blend light or a thermal-polymerization initiator.

  As the photopolymerization initiator, commercially available products may be used, but specific examples include benzophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one (product of Ciba Specialty Chemicals Co., Ltd.) Cure 651), 1-hydroxy-cyclohexyl-phenyl-ketone (product of Ciba Specialty Chemicals Co., Ltd. Irgacure 184), 2-hydroxy-2-methyl-1-phenyl-propan-1-one (Ciba Specialty Chemicals ( Co., Ltd. Product Darocur 1173 Lamberti product Esacure KL200), Oligo (2-hydroxy-2-methyl-1-phenyl-propan-1-one) (Lamberti product Esacure KIP150), (2-hydroxyethyl) -phenyl) -2-Hyd Roxy-2-methyl-1-propan-1-one) (Ciba Specialty Chemicals Co., Ltd. Irgacure 2959), 2-methyl-1- (4- (methylthio) phenyl) -2-morpholin propan-1-one (Ciba Specialty Chemicals Co., Ltd. product Irgacure 907), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 (Ciba Specialty Chemicals Co., Ltd. product Irgacure 369), Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (product of Ciba Specialty Chemicals Co., Ltd. Irgacure 819), bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine Oxide (Ciba Specialty Chemical) Co., Ltd. product CGI403), 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (= Lucirin TPO Ciba Specialty Chemicals product Darocur TPO, manufactured by TMDPO BASF), thioxanthone or its derivatives Among these, one kind or a mixture of two or more kinds is used.

  Further, a tertiary amine such as triethanolamine, ethyl-4-dimethylaminobenzoate, isopentylmethylaminobenzoate or the like may be added for the purpose of photosensitization.

  As the thermal polymerization initiator, a peroxide such as benzoyl peroxide (= BPO) or an azo compound such as azobisisobutylnitrile (= AIBN) is mainly used.

  The amount of light and thermal polymerization initiator to be blended is usually about 0.1 to 10 parts by weight with respect to 100 parts by weight of the composition ((meth) acrylate + inorganic ultrafine particles).

  Moreover, you may use the monomer or oligomer which has cationic polymerizable functional groups, such as an epoxy group, a thioepoxy group, and an oxetanyl group. If necessary, a photocationic initiator or the like is used in combination. Likewise, it is preferably polyfunctional.

  In the present invention, the amount of the (2) curable binder component used is appropriately set according to the application. Preferably, the ultrafine particle component is 1 to 90% by weight, more preferably 10 to 80% by weight, based on the total of the curable binder component and the ultrafine particle component. If it is smaller than this, there is a possibility that the characteristics of the fine particles such as an increase in refractive index are not imparted. If it is larger than this, the mechanical strength may be insufficient.

  Examples of the organometallic compound and / or partial hydrolyzate thereof include usually known organometallic compounds and / or partial hydrolysates thereof, and are not particularly limited. Among them, preferred are organosilicon compounds, and at least one silicon-containing substance selected from the group consisting of hydrolysates, partial hydrolysates, and partial condensates thereof. However, an organosilicon compound represented by the following general formula (a) is preferable.

(R ¹ ) _a (R ² ) _b Si (OR ³ ) _(3-ab) (a)
(Wherein R ¹ and R ² are organic groups having an alkyl group, a halogenated alkyl group, a vinyl group, an allyl group, an acyl group, an acryloxy group, a methacryloxy group, a mercapto group, an amino group, an epoxy group, etc. (It is bonded to silicon by a —C bond. R ³ is an organic group such as an alkyl group having 1 to 8 carbon atoms, an alkoxyalkyl group, or an acyl group.)

Specific examples of R ¹ , R ² and R ³ in the general formula (a) include, for example, an organic group having an alkyl group, such as a methyl group, an ethyl group, a propyl group, or the like having a halogenated alkyl group. Examples of the group include a chloromethyl group and a 3-chloropropyl group. Examples of the organic group having an acyl group include an acetoxypropyl group. Examples of the organic group having an acryloxy group include a 3-acryloxypropyl group. The organic group having a group is a methacryloxypropyl group, the mercapto group is an organic group, the mercaptomethyl group is an amino group, the 3-aminopropyl group is an epoxy group, etc. Examples of the organic group to be contained include 3-glycidoxypropyl group, and examples of the alkoxyalkyl group include methoxyethyl group. The

  Specific examples of the compound represented by the general formula (a) include methyltrimethoxysilane, ethyltriethoxysilane, chloromethyltrimethoxysilane, 3-chloropropyltriethoxysilane, and 3-chloropropyltriacetoxy. Silane, vinyltrimethoxysilane, vinyltriethoxysilane, allyldimethoxysilane, allyltriethoxysilane, acetoxypropyltrimethoxysilane, 3-acryloxypropyldimethylmethoxysilane, (3-acryloxypropyl) methyldimethoxysilane, methacryloxymethyl Triethoxysilane, methacryloxypropyldimethylethoxysilane, methacryloxypropyldimethylmethoxysilane, methacryloxypropylmethyldiethoxysilane, methacryloxypropylmethyl Methoxysilane, methacryloxypropyltriethoxysilane, methacryloxypropyltrimethoxysilane, mercaptomethylmethyldiethoxysilane, mercaptomethyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropyl Trimethoxysilane, p-aminophenyltrimethoxysilane, 3-aminipropylmethyldiethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, (3-glycidoxypropyl) dimethylethoxysilane, ( 3-glycidoxypropyl) methyldiethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, (3-glycidoxypropyl) trimethoxysilane And the like, it is possible to use them alone or as a mixture.

  In the present invention, among the organosilicon compounds represented by the general formula (a), (3-glycidoxypropyl) trimethoxysilane, (3-glycidoxypropyl) methyldiethoxysilane, Sidoxypropyl) methyldimethoxysilane and their hydrolysates, partial hydrolysates and partial condensates are more preferably used. These can be used alone or as a mixture.

  Moreover, the compound represented by the following general formula (b) can also be used together as organosilicon compounds other than the said organosilicon compound.

Si (OR ³ ) ₄ (b)
(In the formula, R ³ is an organic group such as an alkyl group having 1 to 8 carbon atoms, an alkoxyalkyl group, or an acyl group.)

Specific examples of ^{R 3} in the general formula (b), same thing can be mentioned as ^{R 3} in the general formula (a).

  Specific examples of the compound represented by the general formula (b) include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetra-n-propoxysilane, tetra-n-butoxysilane, and tetra-tert. -Butoxysilane, tetra-sec-butoxysilane and the like. These can be used alone or as a mixture.

  Hydrolysis of the organosilicon compound represented by the general formula is carried out by adding hydrochloric acid or the like. Thereby, a part or all of the alkoxy group is hydrolyzed. Alcohols such as methanol, cellosolves such as methyl cellosolve, esters such as ethyl acetate, ethers such as tetrahydrofuran, ketones such as acetone, halogen hydrocarbons such as chloroform, hydrocarbons such as toluene and heptane, etc. Dilution may be performed.

  The organosilicon compound can be cured without a catalyst, but a curing catalyst can be added to accelerate the reaction.

  The curing catalyst for accelerating the curing reaction is not particularly limited, and specifically, for example, metal complexes such as aluminum acetylacetonate and iron acetylacetonate, and alkali metal organic carboxylates such as potassium acetate and sodium acetate. Perchlorates such as aluminum perchlorate, organic carboxylic acids such as maleic acid, maleic anhydride, fumaric acid, fumaric anhydride, itaconic acid, itaconic anhydride, nitrogen-containing organic compounds such as methylimidazole and dicyandiamide, titanium Examples thereof include metal alkoxides such as alkoxides and zirconium alkoxides. Of these, use of aluminum acetylacetonate is particularly desirable from the viewpoint of scratch resistance, pot life, and the like. The amount of the catalyst used for the above is desirably in the range of 0.1 to 5% by weight with respect to the solid content in the film. If it is smaller than this range, the effect as a catalyst may be low. On the other hand, if it is larger than this range, the hardness and scratch resistance may be insufficient.

  The applied film is cured by hot air drying, and the curing condition is preferably 80 to 200 ° C. in hot air, particularly preferably 90 to 120 ° C. The curing time is preferably 0.5 to 5 hours, particularly 1 to 2 hours.

  In the present invention, a photocurable silicon compound can also be suitably used.

  Examples of the photocurable silicon compound include those having a polymerizable double bond group such as an acryl group or a methacryl group that reacts and crosslinks upon irradiation with ionizing radiation. Specifically, one-end vinyl functional polysilane, both Examples thereof include terminal vinyl functional polysilane, one-end vinyl polysiloxane, and both-end vinyl polysiloxane.

  Moreover, the binder component which bridge | crosslinks and hardens | cures curable resin and a hardening | curing agent may be sufficient. Examples of such thermosetting resins include epoxy resins, silicon resins, silicone resins, phenol resins, urea resins, melamine resins, unsaturated polyester resins, polyurethane resins, and the like. Examples of ionizing radiation curable resins include resins having a functional group such as a radical polymerizable unsaturated group (acryloyloxy group, styryl group, vinyloxy group, etc.) and / or a cationic polymerizable group (epoxy group, thioepoxy group, etc.). Can be mentioned.

  As required for these curable resins, crosslinking agents (epoxy compounds, polyisocyanate compounds, polyol compounds, polyamine compounds, melamine compounds, etc.), polymerization initiators (azobis compounds, organic peroxide compounds, organic halogen compounds, onium salts) Conventionally known compounds such as curing agents such as compounds, UV photoinitiators such as ketone compounds) and polymerization accelerators (organic metal compounds, acid compounds, basic compounds, etc.) can be used.

  Although it is inferior in mechanical strength, it is also possible to use a conventionally known thermoplastic polymer. For example, polyacrylic resin, polymethacrylic resin, imide resin, polystyrene resin, polyester resin, polyether resin, vinyl chloride resin, urethane resin and the like can be mentioned.

  The (3) water or organic solvent of the present invention will be described.

  The organic solvent used in the coating liquid for forming a cured film of the present invention is not particularly limited, and specifically, for example, alcohols such as methanol, ethanol, and isopropanol, glycols such as methyl cellosolve, ethyl cellosolve, and propylene glycol monomethyl ether Examples include ethers, esters such as ethyl acetate, ethers such as tetrahydrofuran, ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, halogen hydrocarbons such as chloroform, and hydrocarbons such as toluene and heptane. You may mix and use seeds or more.

  The solid content (mainly curable binder component + ultrafine particle component) concentration in the coating liquid for forming a cured film is preferably adjusted so that the solid content concentration is 0.1 to 40% by weight in order to obtain a cured film. Depending on the coating method and the film thickness desired to be produced, it is appropriately set. If it is smaller than this range, the amount of the component (3) to be used is increased and it is not efficient. If it is larger than this range, the viscosity of the coating liquid for forming a cured film is increased and it may be difficult to produce a coating film.

  As a method for preparing the coating liquid of the present invention, the coating type inorganic oxide ultrafine particles (1), that is, the sol liquid in which the two-layer silicon oxide-coated tin-modified rutile titanium oxide ultrafine particles are dispersed in water or an organic solvent. The organic solvent may be added as necessary after mixing the binder component and the organic solvent may be added to the component (1) or (2) in advance and then mixed.

  In the present invention, the component (1) is preferably a coated inorganic oxide ultrafine particle, that is, only a two-layer silicon oxide-coated tin-modified rutile titanium oxide ultrafine particle, but the effect of improving the refractive index is inferior to that of the ultrafine particle. It can also be used in combination with other inorganic oxide ultrafine particles. Examples thereof include colloidal silica and antimony oxide colloid. Moreover, it is possible to mix | blend microparticles | fine-particles, such as tin dope indium oxide (ITO) and antimony dope tin oxide (ATO), in order to provide electroconductivity.

  Further, various surfactants such as silicone or fluorine can be contained in the coating solution for the purpose of improving the wettability during coating and the smoothness of the cured film. Furthermore, ultraviolet absorbers, antioxidants, antistatic agents, disperse dyes, pigments, pigments, dyeing improvers, and the like can be added.

  The coating liquid for forming a cured film according to the present invention is excellent in dispersibility of coated inorganic oxide ultrafine particles, that is, bilayer silicon oxide-coated tin-modified rutile titanium oxide ultrafine particles. The coating liquid for forming a cured film is applied to the substrate surface, dried, and cured by a chemical reaction process such as irradiation with ionizing radiation as necessary, so that some functions resulting from the physical properties of the ultrafine particles can be obtained. In addition, a cured film having light resistance, weather resistance, transparency, scratch resistance, abrasion resistance, heat resistance, etc. that can be put to practical use can be obtained.

  The coating liquid for forming a cured film of the present invention includes, for example, a spin coat method, a dip method, a spray method, a slide coat method, a bar coat method, a roll coater method, a meniscus coater method, a flexographic printing method, a screen printing method, and a bead coater method. It can apply | coat on a base material by various methods, such as.

  By the above method, a cured film having a refractive index of 1.5 or more, preferably 1.7 or more is obtained, and is suitably used for a plastic sheet, a plastic film or the like that requires transparency, and particularly as an optical member having a high refractive index. Can be used.

  Next, the antireflection film according to the present invention will be described. The coating liquid for forming a cured film according to the present invention is a layer of a multilayer type antireflection film formed by laminating two or more layers having optical transparency and different refractive indexes from each other, mainly a medium to high refractive index layer. Can be used. In a multilayer antireflection film, the layer with the highest refractive index is called the high refractive index layer, the layer with the lowest refractive index is called the low refractive index layer, and the other layers with intermediate refractive indices are medium refractive. This is called the rate layer. Therefore, the middle refractive index layer of the antireflection film may be composed of a high refractive index cured film formed from the coating liquid of the present invention. The middle refractive index layer may be composed of the above-mentioned binder, or may be adjusted by changing the ratio between the ultrafine particles and the binder component of the coating liquid for forming a cured film of the present invention. As the low refractive index layer, a thin film prepared by a known method can be used.

  These film thickness and refractive index are well-known conditions, and for example, it is preferable to satisfy the film thickness ranges described in JP-A-59-50401 for practical use. What is necessary is just to set according to a refractive index in order to maintain an optical characteristic.

For example, on a substrate (refractive index: n _s ), a high refractive index layer (first layer) (refractive index: n ₁ , film thickness: d ₁ ), low refractive index layer (second layer) (refractive index: n ₂ , The reflectance R in the case of a laminated body having a two-layer structure laminated in the order of film thickness: d ₂ ) is (2) under the condition (1) (the wavelength of light is λ, and the refractive index of the atmosphere is n ₀ ). (Quoted from Optical Overview II (Asakura Shoten)).

n ₁ · d ₁ = n ₂ · d ₂ = k · λ / 4 (k: odd number is usually 1) (1)
R = {(n ₂ ² −n ₁ · _ns ) / (n ₂ ² + n ₁ · _ns )} ² (2)

  In order to prevent reflection, by selecting as in (3), it can be reduced to 1% or less which is practically required.

(N ₂ / n ₁ ) ² = n _s · n ₀ (3)

For example, if the base material n _s = 1.4 to 1.65 and the low refractive index layer is a SiO ₂ sol-gel coating film, n = 1.74 to 1.89.

  The lower the reflectance, the better. Specifically, the average reflectance in the wavelength region of 450 to 650 nm is preferably 2% or less, more preferably 1% or less, and most preferably 0.7% or less.

  By combining such a high refractive index layer and a low refractive index layer having a refractive index of 1.30 to 1.55, a transparent laminate having a two-layer or three-layer structure is formed on the substrate, thereby the surface of the substrate It is possible to prevent reflection. For example, in the case of a two-layer film, the refractive index of the low refractive index layer may be relatively higher by increasing the refractive index of the high refractive index layer. In this sense, the degree of freedom in selecting a material for the low refractive index layer is increased.

By increasing the refractive index of the high refractive index cured film to 1.5 to 2.8, preferably 1.7 or more by the method of the present invention, the refractive index of the low refractive index cured film can be increased, and the fluororesin It is possible to select from a wide range of materials such as silicone resin, acrylic resin, and SiO ₂ produced by a sol-gel method. Specific examples include the composition obtained by hydrolyzing and condensing an organosilicon compound as described above. Alternatively, a composition prepared by using an organosilicon compound in which fluorine is contained in an organosilicon compound or an oligomer thereof as a resin component can be given. Alternatively, a fluorine resin such as ethylene trifluoride chloride, a polyacetal resin, a silicone resin, and the like can be given. Further LiF, such as those with a low refractive index of the inorganic fine particles added further low refractive index resin such as MgF _2, SiO ₂ and the like.

  The high refractive index cured film and the antireflection laminate in the present invention have practically sufficient performance by themselves, but in order to further improve the performance, a film processed by a vacuum deposition method or the like is separated into another layer. Can be used together, or can be multi-layered into three or more layers.

  The high refractive index layer can also serve as a hard coat layer. In order to obtain antireflection performance, a thin film with a layer structure of a high refractive index layer / low refractive index layer should be formed on the hard coat layer, but the same applies only to the low refractive index layer by increasing the refractive index of the hard coat layer. Therefore, the manufacturing process can be simplified.

  The antireflective film obtained by the present invention is composed of coated inorganic oxide ultrafine particles, that is, bilayer silicon oxide-coated rutile titanium oxide ultrafine particles, in addition to metal oxide fine particles having high conductivity but low refractive index. By doing so, it can also be suitably used as an antistatic layer provided on the antireflection film or a conductive transparent thin film. Furthermore, since it has a high refractive index, it can be added not only to the antireflection laminate as a simple conductive transparent thin film, but also as a layer that also functions as a medium to high refractive index layer constituting the antireflection film. You can also It can also be used as a high refractive index hard coat film having an antistatic function.

  The antireflection laminate may be provided with layers other than those described above. For example, an adhesive layer, a shield layer, a sliding layer, a primer layer, or the like may be provided. The shield layer is provided to shield electromagnetic waves and infrared rays.

  The substrate for applying the cured film forming coating solution of the present invention is not particularly limited. Preferred substrates include, for example, glass plates, triacetate cellulose (TAC), polyethylene terephthalate (PET), diacetyl cellulose, acetate butyrate cellulose, polyethersulfone, (meth) acrylic resins, urethane resins, and ester resins. Examples thereof include films formed of various resins such as polycarbonate, polysulfone, polyether and polyether ketone. Moreover, the shape of the base material layer is not particularly limited, and examples thereof include a flat shape such as a film or a plate, a curved surface shape such as a CRT surface, and a spherical or aspherical lens shape such as a microlens.

  By using an anti-reflection laminate including these base material layers, various optical lenses such as eyeglass lenses, Fresnel lenses, lenticular lenses and micro lens arrays such as CCDs, camera lenses, plasma display panels (PDPs), liquid crystals It is suitable as an optical member of a display device (LCD), an electroluminescence display (ELD), or a cathode ray tube display device (CRT).

  Therefore, the coating liquid for forming a cured film according to the present invention is suitable for forming a cured film having a high refractive index that requires high transparency, and has the high refractive index found by the present inventors. Since ultrafine particles having excellent dispersibility, light resistance, weather resistance, and transparency are used, it is particularly suitable for forming an intermediate to high refractive index layer of an antireflection film.

  Further, the coating solution for forming a cured film according to the present invention has a long pot life because it has excellent dispersion stability over a long period of time, and can be used practically even after being stored for a long period of time. A cured film having transparency, scratch resistance, abrasion resistance, and heat resistance can be formed.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.

(Preparation of two-layer silicon oxide-coated tin-modified rutile-type titanium oxide ultrafine particle sol solution dispersed in an organic solvent)
[Production Example 1]
Tin tetrachloride pentahydrate 0.27 g was charged into a 100 ml eggplant type flask, dissolved in 50 ml of ion-exchanged water, and 5 ml of a hydrochloric acid aqueous solution of titanium oxide chloride (containing 15 wt% Ti) was added. The pH of the solution was -0.1. (Ti concentration of Ti = 0.45, Sn / Ti = 0.03) The mixture was stirred with a magnetic stirrer and heated at 50 ° C. for 1 hour to obtain a white precipitate. Centrifugation was performed, and the white precipitate was collected and redispersed in ion-exchanged water. Ultrafiltration was performed to obtain a sol solution having a solid content of 2% by weight. This solid was subjected to powder X-ray diffraction measurement and electron microscope observation. When powder X-ray diffraction measurement was performed after hot-air drying at 120 ° C. for 2 hours, it was a titanium oxide rutile type. The crystal diameter was calculated from the half-value width of the diffraction peak using the Debye-Scherrer equation. As a result, the average crystal diameter was 5 nm for the minor axis and 8 nm for the major axis, respectively. The observation with an electron microscope was performed using a transmission electron microscope, and a solution obtained by dropping a diluted sol solution onto a mesh was observed at a magnification of 200,000 times and 2 million times. As a result, it was a rutile type titanium oxide having an average aggregated particle size of 23 nm. The elemental molar ratio of Sn / Ti by inductively coupled plasma analysis was 0.02.

  After 2500 g of this tin-modified rutile type titanium oxide ultrafine particle sol solution was adjusted to pH <7, it was heated to 80 ° C. 125 g of a 2% by weight aqueous silicon oxide solution was added dropwise over 1 hour, and the mixture was further heated for 30 minutes. After cooling to room temperature, a 1 mol / l sodium hydroxide aqueous solution was added to form a basic sol solution. The temperature was raised to 80 ° C., and 625 g of a 2 wt% aqueous silicon oxide solution was added dropwise over 2 hours, and further heated for 4 hours. The mixture was purified by ultrafiltration to obtain a 2 wt% sol solution. The dispersion medium was replaced with methanol by a rotary evaporator and concentrated to obtain a 20 wt% methanol-dispersed sol. The weight ratio of coating layer / fine particles by inductively coupled plasma analysis was = 0.13 / 1.

[Production Example 2]
Next, sulfuric acid was added to 100 g of the 20 wt% methanol-dispersed sol solution prepared in Production Example 1 to adjust the pH to 5, 1 g of 3-methacryloxypropyltrimethoxysilane was added, and the mixture was heated at 50 ° C. The operation of adding propylene glycol monomethyl ether and concentrating with an evaporator was repeated to obtain a 20 wt% propylene glycol monomethyl ether dispersed sol.

[Production Example 3]
Next, after repeating the operation of concentrating the 20 wt% propylene glycol monomethyl ether dispersion sol prepared in Production Example 2 by adding methyl isobutyl ketone with an evaporator, 0.2 g of dodecylamine was added and heated at 50 ° C. to obtain 20 wt. % Methyl ethyl ketone dispersion sol.

[Production Example 4]
The same operation as in Production Example 1 was carried out except that 0.9 g of tin tetrachloride pentahydrate was used in Production Example 1. (Feed Ti concentration = 0.45, Sn / Ti = 0.1) When the solid content of the obtained sol solution was analyzed in the same manner as in Production Example 1, the element molar ratio of Sn / Ti was 0.06. It was a rutile type titanium oxide having an average crystal diameter of 5 nm for the minor axis and 8 nm for the major axis and an average aggregated particle diameter of 20 nm. The weight ratio of coating layer / fine particles was = 0.13 / 1.

[Production Example 5]
A 20 wt% propylene glycol monomethyl ether dispersed sol was obtained in the same manner as in Production Example 2 except that the 20 wt% methanol dispersed sol liquid prepared in Production Example 4 was used.

[Production Example 6]
A 20 wt% methyl ethyl ketone dispersed sol was obtained in the same manner as in Production Example 3 except that the 20 wt% propylene glycol monomethyl ether dispersed sol liquid prepared in Production Example 5 was used.

(Synthesis of rutile titanium oxide, preparation of resin composition)
[Comparative Production Example 1]
It carried out like manufacture example 1 except not adding a tin tetrachloride pentahydrate. The white precipitate obtained did not redisperse. When analyzed in the same manner, it was a rutile type titanium oxide having an aggregate particle diameter of 200 nm or more. Although the dispersion medium was replaced with methanol by a rotary evaporator and concentrated to a concentration of 20% by weight, gelation and precipitation occurred.

(Preparation of anatase-type titanium oxide ultrafine particle sol solution)
[Comparative Production Example 2]
To 2 L of ion-exchanged water, 20 ml of a hydrochloric acid aqueous solution of titanium oxide chloride (Ti content: 15% by weight) was added and heated at 60 ° C. for 6 hours. After cooling to room temperature, it was concentrated and deionized by ultrafiltration to obtain a sol solution having a solid content of 2% by weight. When the solid content of the obtained sol solution was analyzed in the same manner as in Production Example 1, it was anatase-type titanium oxide having an average of 5 nm on both the minor axis and the major axis. The dispersion medium was replaced with methanol by a rotary evaporator and concentrated to obtain a 20 wt% methanol-dispersed sol.

(Preparation of zirconium oxide-coated anatase-type titanium oxide ultrafine particle sol solution)
[Comparative Production Example 3]
To 2 L of ion-exchanged water, 20 ml of a hydrochloric acid aqueous solution of titanium oxide chloride (Ti content: 15% by weight) was added and heated at 60 ° C. for 6 hours. 50 g of an aqueous solution in which 32 g of zirconium oxide chloride octahydrate was dissolved was dropped, heated to 90 ° C., and heated for 1 hour. After cooling to room temperature, ultrafiltration was performed. After cooling to room temperature, it was concentrated and deionized by ultrafiltration to give a 2 wt% sol solution. When the solid content of the obtained sol solution was analyzed in the same manner as in Example 1, it was anatase-type titanium oxide having an average of 5 nm on both the minor axis and the major axis. The composition of the zirconium oxide-coated anatase-type titanium oxide ultrafine particles was zirconium oxide / titanium oxide weight ratio = 0.85 / 1 in terms of oxide. The dispersion medium was replaced with methanol by a rotary evaporator and concentrated to obtain a 20 wt% methanol-dispersed sol.

[Comparative Production Example 4]
A commercially available antimony pentoxide ultrafine particle sol solution was used as a 20 wt% methanol-dispersed sol solution.

(Preparation of coating solution for forming a high refractive index cured film)

10.5 g (solid content 2.1 g) of the 20 wt% dispersion sol obtained in Production Example 2 and 1.2 g of a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (DPHA, Nippon Kayaku Co., Ltd.) Made) and then 3.0 g of ethyl cellosolve was added. Furthermore, 0.17 g of 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (TMDPO) as a photoinitiator and a Si-based surfactant (trade name FZ-2110 manufactured by Nippon Unicar Co., Ltd.) were added, The solution was sufficiently stirred to prepare a coating solution for forming a cured film (1-2).
Similarly, coating liquids for forming a cured film (1-3), (1-5), and (1-6) were prepared using the sol liquids obtained in Production Examples 3, 5, and 6.

To 15 g of (3-glycidoxypropyl) trimethoxysilane, 3.5 g of 0.001 N hydrochloric acid was added dropwise over 2 hours and stirred for 3 hours. 30 g of ethyl cellosolve was added to prepare a solution of a partial hydrolyzate of (3-glycidoxypropyl) trimethoxysilane. Next, 5.2 g of the above-mentioned (3-glycidoxypropyl) trimethoxysilane partial hydrolyzate solution was added to 11 g of the methanol sol solution of Production Example 1, and 50 mg of aluminum acetylacetonate as a curing agent and a surfactant ( 10 mg of Nippon Unicar Co., Ltd .: L7604) was added and stirred to prepare a cured film forming coating solution (2-1).
Similarly, a coating solution (2-4) for forming a high refractive index cured film was prepared using the sol solution obtained in Production Example 4.

(Preparation of cured film)

  A triacetyl cellulose (TAC) film was used as a substrate, and the coating solution obtained in Example 1 was applied by a bar coating method and dried at room temperature for 1 hour, and then a metal halide lamp (strength 120 W / cm) was used. Irradiated to form a cured film.

  A triacetyl cellulose (TAC) film was used as a substrate, and the coating solution obtained in Example 2 was applied by the bar coating method and thermally cured at 100 ° C. to form a cured film.

[Comparative Example 1]
A cured film forming coating solution (2-1 ′), (2-2 ′), (2-4) in the same manner as in Example 2 except that the sol solution obtained in Comparative Production Examples 1, 2, and 4 was used. ')created.
Further, a high refractive index cured film forming coating solution (2-3 ′) was prepared in the same manner as in Example 2 using 1.3 g of the sol solution obtained in Comparative Production Example 3.

[Comparative Example 2]
A cured film was formed in the same manner as in Example 4 using the coating liquid for forming a cured film obtained in Comparative Example 1.

  With respect to the coating solution for forming a cured film obtained by the above method, the dispersion stability was evaluated as described below, and the scratch resistance, light resistance, and refractive index were evaluated as follows for the cured film. The results are shown in Table 1.

(A) Dispersion stability: A change when the prepared coating solution for forming a cured film was stored at room temperature for one month was evaluated by the following index.
○ ... No change △ ... Increased viscosity × ... Gelled

(B) Scratch resistance: The surface was rubbed with steel wool (# 0000) under a 1 kg load, and the degree of damage was visually evaluated. Judgment criteria are as follows.
○… Almost scratches △… Slightly scratches ×… Severely scratches

(C) Light resistance (adhesion): The obtained base material with a hard coat film was peeled off in an adhesion test after irradiation for 300 hours by a solar simulator (Type: sss-252161-ER manufactured by Ushio Electric Co., Ltd.). No and no yellowing were marked as ◯. The adhesion between the base material and the cured film was measured by a cross-cut tape test according to JISK-5600. That is, the knife is cut on the surface of the substrate in the sense of 1 mm, and 25 squares of 1 mm 2 are formed. Next, the cellophane adhesive tape was strongly pressed onto it, and then suddenly pulled away from the surface in the direction of 90 ° and peeled off, and then the remaining grid of the coating film was used as an adhesion index.
○ ... No peeling (25/25)
× ... Peeled (24/25 or less)

(D) Light resistance (scratch resistance): The scratch resistance after irradiation was examined. That is, the surface was rubbed with a 1 kg load with steel wool (# 0000), and the degree of damage was visually evaluated. Judgment criteria are as follows.
○… Almost scratches △… Slightly scratches ×… Severely scratches

(E) Measurement of refractive index of cured film: A coating solution was applied on a quartz substrate by spin coating to a film thickness of about 700 mm and dried with hot air, and an automatic wavelength scanning ellipsometer M-150 (JASCO Corporation ), And the refractive index at 550 nm was measured.

(Preparation of antireflection laminate)

  Except having used 12g of sol liquid obtained by manufacture example 5, it carried out similarly to Example 3 and obtained the base material with a cured film. On this, a low refractive index layer made of an ultraviolet curable acrylic resin (refractive index 1.50) was provided to obtain an antireflection laminate.

  Except having used 10g of sol liquid obtained by manufacture example 5, it carried out similarly to Example 3 and obtained the base material with a cured film. On this, a low refractive index layer made of an ultraviolet curable acrylic resin (refractive index 1.47) was provided to obtain an antireflection laminate.

  Except having used 2.9g of sol liquid obtained in manufacture example 5, it carried out similarly to Example 3 and obtained the base material with a cured film. A low refractive index layer made of a fluororesin (refractive index 1.34) was provided thereon to form an antireflection laminate.

  The antireflection laminate obtained by the above method was evaluated for reflectivity as shown below. The results are shown in Table 2.

(F) Measurement of reflectance: Using a UV-visible near-infrared spectrophotometer, the reflection spectrum is measured at an incident angle of 5 °, the light reflectance (%) at a wavelength of 430 to 700 nm is obtained, and the minimum at a wavelength of 430 to 700 nm. The reflectance (%) was measured. The lower the value, the better the antireflection performance.
○… less than 0.5% ×… 0.5% or more

  As shown in Table 1, by applying the two-layer silicon oxide coating method found by the present inventors to tin-modified rutile-type titanium oxide ultrafine particles, a high refractive index and more efficient than the conventional metal oxide coating It can be seen that the photocatalytic action of titanium oxide is suppressed. Furthermore, as shown in Table 2, the low refractive index film is laminated on these cured films and can be used as an antireflection laminate, whereby the reflectance in the visible region can be reduced and practically sufficient antireflection. An optical member that exhibits the effect can be provided.

  According to the present invention, ultrafine particles having a high refractive index and excellent dispersibility, light resistance, weather resistance, and transparency, a sol solution in which the ultrafine particles are dispersed in water or an organic solvent, and an antireflection laminate including the same It is possible to provide a coating solution for forming a high refractive index cured film excellent in dispersion stability and coating suitability suitable for medium to high refractive index layers of the body, and further a coating solution for forming an antireflection film. Furthermore, it has a high refractive index with good light resistance, weather resistance, transparency, scratch resistance, abrasion resistance, heat resistance, antistatic properties, etc. when applied and cured on a transparent substrate such as resin or glass. A cured film, that is, an antireflection film and an antireflection film laminate, and an optical member including the same can be provided.

  According to the present invention, it is particularly preferable that a display surface such as a plasma display panel (PDP), a liquid crystal display device (LCD), an electroluminescence display (ELD) or a cathode ray tube display device (CRT), an eyeglass lens, or a Fresnel lens. Anti-reflective film formation suitable for forming anti-reflective film covering the surface of various optical lenses such as lenticular lens and micro lens array such as CCD and camera lens, especially medium to high refractive index layer Coating liquid, antireflection film laminate, and optical member comprising the same can be provided.

Claims (12)

  (1) An inorganic oxide ultrafine particle containing titanium oxide having a rutile crystal structure with a refractive index of 1.5 to 2.8 is used as a nucleus (A), and is composed of a coating layer (B) containing silicon oxide. A coating solution for forming a high refractive index cured film, comprising: coated inorganic oxide ultrafine particles having an inorganic oxide coating layer or sol thereof; (2) a curable binder component; and (3) water or an organic solvent. The rutile type titanium oxide ultrafine particles in the inorganic oxide ultrafine particles containing titanium oxide having the rutile type crystal structure of the nucleus (A),
In the presence of a tin compound having a molar ratio of tin to titanium (Sn / Ti) of 0.001 to 2, a titanium compound aqueous solution having a Ti concentration of 0.07 to 5 mol / l is reacted in a pH range of −1 to 3. Obtained tin-modified rutile titanium oxide ultrafine particles having a Sn / Ti composition molar ratio of 0.001 to 0.5,
The coating layer containing silicon oxide (B) is of a two-layer coating type, the inner layer has a coating layer obtained by the step (1), and the outer layer is obtained by the step (2), _{2. The} coating liquid for forming a high refractive index cured film according to claim 1, wherein the coating is a coated inorganic oxide ultrafine particle, wherein the weight ratio of the oxide coating layer is 0.001 to 20 in terms of SiO2.
(1) Step of reacting silicon oxide having a weight ratio with respect to the nucleus (A) of 0.001 to 10 in terms of SiO ₂ with the nucleus (A) under the condition of pH <7 (2) with respect to the nucleus (A) The step of reacting the silicon oxide having a weight ratio of 0.001 to 10 in terms of SiO ₂ with the coated ultrafine particles obtained in (1) under the condition of pH ≧ 7   The coating liquid for forming a high refractive index cured film according to claim 1 or 2, wherein the coated inorganic oxide ultrafine particles have a minor axis and a major axis of 2 to 20 nm.   The coating liquid for forming a high refractive index cured film according to any one of claims 1 to 3, wherein an average aggregate particle diameter of the aggregate crystals composed of the coated inorganic oxide ultrafine particles is 10 to 100 nm.   The coating liquid for forming a high refractive index cured film according to any one of claims 1 to 4, wherein the coated inorganic oxide ultrafine particles are a sol liquid dispersed in water or an organic solvent.   6. The coated high refractive index cured film according to claim 1, wherein the surface of the coated inorganic oxide ultrafine particles is surface-treated with an organosilane compound and / or an amine. Coating liquid.   The curable binder component (2) is at least one of a photocurable and / or thermosetting organic monomer or oligomer, a resin, and an organometallic compound and / or a partial hydrolyzate thereof. The coating solution for forming a high refractive index cured film according to any one of the above.   The cured film formed by apply | coating and hardening the coating liquid for high refractive index cured film formation in any one of Claims 1-7.   The antireflective film using the coating liquid for high refractive index cured film formation in any one of Claims 1-7, or the cured film of Claim 8.   An antireflective film formed by laminating two or more thin films having different refractive indexes, at least one of which is a coating solution for forming a high refractive index cured film according to any one of claims 1 to 7, or claim 8. The antireflection film according to claim 9, wherein the antireflection film is a layer using the cured film according to claim 1, and the layer is a medium to high refractive index layer.   High refractive index layer / low refractive index layer, hard coat layer / high refractive index layer / low refractive index layer, or hard coat layer / medium refractive index layer / high refractive index layer / low refractive index on at least one surface of the substrate A high-refractive-index cured film-forming coating according to any one of claims 1 to 7, wherein the anti-reflective laminate having a multilayer structure in which refractive index layers are sequentially laminated, wherein the high-refractive index layer and the medium-refractive index layer are An antireflection laminate comprising a liquid or a layer using the cured film according to claim 8.   An optical member provided with the antireflection film according to claim 10 or the antireflection laminate according to claim 11.