JP4673664B2 - High refractive index resin composition for coating - Google Patents

Description

  The present invention is an ultrafine particle having a high refractive index and excellent light resistance, a sol liquid and a coating liquid containing the same, as well as scratch resistance, surface hardness, wear resistance, adhesion, transparency, heat resistance, and light resistance. In addition, the present invention relates to a coating film, a resin composition, and a method for producing the same, which have good weather resistance, ultraviolet shielding properties and the like, and do not generate interference fringes when formed on a substrate.

  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. Has been done. However, the present situation is that the rutile-type titanium oxide ultrafine particles and the sol liquid that can be used industrially have not been obtained yet.

  For example, in a method of originally manufacturing a low refractive index type anatase type titanium oxide, a method of adding tin as a doping agent and forcibly changing to a rutile type has been reported. According to the method described by H. Cheng et al. In Chem. Mater., 7, 663, (1995), the compound is synthesized by a hydrothermal synthesis method under strongly acidic and high concentration conditions. However, because of the high temperature of 220 ° C., the crystal diameter exceeds 20 nm, and tin oxide is mixed, so that there is a disadvantage that a good rutile type titanium oxide cannot be obtained. In addition, according to the method described in Nano Mater., 4, 663, (1994) by XZDing et al., A titanium tetrabutoxide water / ethanol mixed solution was used as a raw material under conditions of 60 ° C. Hydrochloric acid is added as a hydrate and catalyst to convert the anatase form to the rutile form. However, this method also has the disadvantage that the anatase type remains or tin oxide is produced. In Patent Document 1, an anatase type is usually converted into a rutile type by adding a tin compound, but has the same drawbacks.

  On the other hand, a method for synthesizing rutile titanium oxide at a low temperature has been reported by H.D.Nam et al. In Jpn. J. Appl. Phys., 37, 4603 (1998). However, according to this method, an aggregate having an aggregate particle diameter of 200 to 400 nm in which long-fiber rutile titanium oxide is gathered is generated.

  On the other hand, low refractive index diethylene glycol bisallyl carbonate resin (refractive index of 1.50) has been used for plastic spectacle lenses, but in recent years, a thiol compound and an isocyanate compound described in Patent Document 2 are thermally polymerized. , A polythioepoxy resin lens (refractive index of 1.60 to 1.70) obtained by forming a thiourethane bond, and a polythio obtained by ring-opening thermal polymerization of a thioepoxy compound described in Patent Document 3. Epoxy resin lenses (refractive index of 1.70 or more) have been developed. However, since plastic lenses have the drawback of being scratch resistant and easily scratched, a method of preparing a coating solution using silica sol and an organosilicon compound and providing a hard coat film on the surface has been performed.

  Further, since the photocurable hard coat film can be easily formed, it is used as a hard coat film for improving the scratch resistance.

  In addition, plastic lenses have the disadvantage of low impact resistance. Therefore, a method of applying a primer film between the base material and the hard coat film to absorb impact is used. However, since the base material has a high refractive index and a low refractive index, interference fringes due to a difference in refractive index from the base material are seen in the coating film, resulting in a problem of poor appearance. Therefore, the refractive index of the hard coat film, the primer film, or the photocurable hard coat film needs to be close to the refractive index equivalent level of the substrate.

  Similarly, ultra-fine particles of high refractive index with excellent light resistance and weather resistance, and sol liquid are optical lenses (glass lenses, pick-up lenses in information recording devices such as CDs and DVDs, lenses for photographing devices such as digital cameras), Optical prisms, optical waveguides, optical fibers, thin film moldings, optical adhesives, materials for high refractive optical members such as optical semiconductor sealing materials, etc., as well as plastic deterioration prevention additives, cosmetic additives, automotive window glass, There are also demands in the field of products such as plasma displays, liquid crystal displays, EL displays, optical members such as optical filters, and metal materials, ceramic materials, glass materials, plastic materials, etc. for refractive index adjustment.

  Up to now, antimony oxide has been recommended as a metal oxide ultrafine particle and sol solution to be added to the coating liquid for increasing the refractive index of the coating film, but the refractive index of the plastic substrate of the lens is 1.6 or more as recently. In this case, this antimony oxide can no longer be used. This is because antimony oxide itself has a refractive index of 1.7, but is used by being filled in an organosilicon compound having a low refractive index, so that the refractive index as a coating film is lower than that of the substrate.

  As a means for solving such problems, a technique of containing ultrafine particles made of anatase-type titanium oxide having a refractive index higher than that of antimony oxide or the like in the hard coat film, primer film and photo-curable hard coat film is currently used. It has been.

  However, it has been found that a coating film using anatase-type titanium oxide ultrafine particles is inferior in light resistance. In other words, the photocatalytic action of titanium oxide causes organic matter decomposition due to electron-holes generated by light absorption, scratch resistance, surface hardness, abrasion resistance, transparency, heat resistance, light resistance, weather resistance, UV shielding performance Etc. is a problem.

  At present, for the purpose of improving the light resistance of such interference fringes and anatase-type titanium oxide ultrafine particle-containing coat film, for example, as described in Patent Document 4, ultrafine particles composed of anatase-type titanium oxide and a metal oxide, Alternatively, ultrafine particles obtained by coating anatase-type titanium oxide with a metal oxide, and a coating liquid and a coating film using the same are applied.

  These are all aimed to inactivate anatase-type titanium oxide ultrafine particles by metal oxide coating. Thus, light resistance is improved by coat | covering a titanium oxide ultrafine particle with a metal oxide. However, since titanium oxide used is anatase type, the refractive index is about 2.5, and when coated with a metal oxide to improve light resistance, the refractive index is greatly reduced. The refractive index is lower than that of the original anatase titanium oxide, and the effect of improving the refractive index of the coating film is low. 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 when used on a high refractive index substrate, particularly a spectacle lens substrate of 1.70 or more, it has light resistance. It is difficult to improve the refractive index of the coating film as it is, and the interference fringes cannot be completely eliminated at present.

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.
Japanese Patent No. 2783417 Japanese Patent Laid-Open No. 9-110956 JP 2002-140883 A JP 2001-123115 A

  In the present invention, when applied to a substrate having a refractive index of 1.50 or more, particularly 1.70 or more, no interference fringes are generated, and scratch resistance, surface hardness, wear resistance, adhesion, transparency, It is an object of the present invention to provide a hard coating solution, primer coating solution, photocurable hard coating solution, coating film, or resin composition excellent in heat resistance, light resistance, weather resistance, ultraviolet shielding properties, and the like.

  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. Sol liquid with excellent properties can be obtained, and by coating this with antimony oxide and silicon oxide as core ultrafine particles, the average of high refractive index with excellent light resistance, weather resistance, transparency and dispersibility It has been found that composite oxide ultrafine particles having a particle diameter of 1 to 100 nm, that is, composite oxide-coated tin-modified rutile titanium oxide ultrafine particles can be obtained, and the present invention has been completed.

  That is, the present invention relates to a tin-modified rutile having a crystal diameter of 2 to 20 nm using one or more of an organosilicon compound, a hydrolyzate thereof and a condensate thereof, a resin such as polyurethane and polyester, or a photocurable monomer as a matrix component. Hard coating solution, primer coating solution, or photo-curable hard coating solution containing ultrafine particles of type titanium oxide coated with antimony oxide and silicon oxide as essential components, and a refractive index of 1.5 to 2.0 The present invention relates to a coating film or a resin composition in which interference fringes are not formed, which is formed on a base material that is a resin or an inorganic substance.

More specifically,
1. 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. A core fine particle which is a rutile-type titanium oxide ultrafine particle having a Sn / Ti composition molar ratio of 0.001 to 0.5 and a short axis of crystal diameter and a long axis of 2 to 20 nm, and the above core fine particle. containing antimony oxide coating layer to be coated is composed of a silicon oxide target Kutsugaeso covering the antimony oxide coating layer, the minor axis of the crystal diameter, the composite oxide ultrafine particles long axis is 2~20nm Coating composition.
2. The composite oxide ultrafine particle coating layer / nucleus weight ratio is 1/99 to 90/10, and the antimony oxide / silicon oxide weight contained in the antimony oxide coating layer and the silicon oxide coating layer. The coating composition according to 1 , wherein the ratio is 100/1 to 1/50.
3. The composite oxide fine particles refractive index of 1 or 2 coating composition according is 1.5 to 2.8.
4). The composite oxide composed of ultra-fine particles, the average agglomerated particle size, coating composition according to any one of 1 to 3 containing crystal ultrafine particles agglomerates is 10 to 100 nm.
5. The composite oxide ultrafine particles, water or a coating composition according to any one of 1 to 4, containing a sol solution obtained by dispersing in an organic solvent.
6). The coating composition according to any one of 1 to 5, comprising at least one selected from an organosilicon compound, a hydrolyzate thereof and a condensate thereof.
A hard coat film obtained by curing using the coating composition according to 7.6.
8). The coating composition according to any one of 1 to 5, comprising at least one resin or resin monomer.
A primer film obtained by curing using the coating composition according to 9.8.
10. The coating composition according to any one of 1 to 5, comprising at least one photocurable monomer.
A hard coat film obtained by curing using the coating composition according to 11.10.
12 8. The hard coat film according to 7, which has a refractive index of 1.5 to 2.8.
13. 10. The primer film according to 9, having a refractive index of 1.5 to 2.8.
14 11. The hard coat film according to 11, having a refractive index of 1.5 to 2.8.
A substrate on which the hard coat film according to 15.7 or 12 is applied.
A substrate provided with the primer film according to 16.9 or 13.
17. A substrate on which the hard coat film described in 14 or 14 is applied.
A substrate obtained by applying the hard coat film described in 7 or 12 on the primer film described in 18.9 or 13.
19. The base material in any one of 15-18 whose refractive index of a base material is 1.5-2.0.
20. The substrate according to any one of 15 to 19, wherein the substrate is a polythiourethane resin or a polythioepoxy resin.
21. A substrate obtained by further applying an antireflection film on the substrate according to any one of 21.15 to 20.
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. When the tin-modified rutile-type titanium oxide ultrafine particles are coated with antimony oxide and silicon oxide, the ultrafine particles, and when the sol liquid is applied to the coating liquid and the coating film, 1.50 or more, particularly 1.70. Provided is a coating film or a resin composition in which interference fringes are not visible and light resistance is excellent in a base material on which a hard coat, primer, or photocurable coating film formed on the above high refractive index base material is formed. be able to.

  Further, in the present invention, interference fringes are not seen on a base material on which a hard coat, primer, or photocurable hard coat film formed on a high refractive index base material of 1.50 or higher, particularly 1.70 or higher, is visible. It has also become possible to provide a material having excellent scratch resistance, surface hardness, abrasion resistance, adhesion, transparency, heat resistance, light resistance, weather resistance, ultraviolet shielding properties and the like.

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

  The present invention provides a titanium compound aqueous solution having a Ti concentration of 0.07 to 5 mol / l in the coexistence of a tin compound having a molar ratio of tin to titanium (Sn / Ti) of 0.001 to 2, and a pH of −1 to 3. Rutile-type titanium oxide ultrafine particles having a Sn / Ti composition molar ratio of 0.001 to 0.5 and a minor axis of crystal diameter and a major axis of 2 to 20 nm obtained as a result of the reaction are used as core fine particles. And a coating composition containing composite oxide ultrafine particles having a minor axis of crystal diameter and a major axis of 2 to 20 nm, comprising a coating layer containing antimony oxide and silicon oxide.

  First, tin-modified rutile titanium oxide ultrafine particles, which are core fine particles, will be described.

  The tin-modified rutile-type titanium oxide ultrafine particles of the present invention are titanium compounds having a Ti concentration of 0.07 to 5 mol / l in the presence of a tin compound having a molar ratio of tin to titanium (Sn / Ti) of 0.001 to 2. Tin-modified rutile-type titanium oxide ultrafine particles obtained by reacting an aqueous solution in the range of −1 to 3, the Sn / Ti composition molar ratio of the ultrafine particles being 0.001 to 0.5, and A tin-modified rutile-type titanium oxide ultrafine particle, characterized in that the minor axis and the major axis of the crystal diameter are 2 to 20 nm, and the average aggregate particle diameter of crystals of the ultrafine particle aggregate is 10 to 100 nm.

  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 medium 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, when it is set as a coating film, the transparency of a coating 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 media. The sol liquid in which tin-modified rutile-type titanium oxide ultrafine particles are dispersed in water is substituted with an organic solvent such as alcohols such as methanol and cellosolves such as 2-methoxyethanol, and organic solvent-dispersed tin-modified rutile-type titanium oxide It can also be used as an ultrafine particle sol solution.

  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. When the crystal diameter is smaller than 2 nm, the scratch resistance and hardness are insufficient when a coating 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 size is larger than 100 nm, the resulting coating film may become cloudy and opaque.

  Next, a method for preparing the coating layer will be described.

  In the present invention, when the tin-modified rutile-type titanium oxide ultrafine particles synthesized above or a sol solution thereof is used for an optical material, a hard coat material, a resin lens, etc., 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 antimony oxide and silicon oxide. In addition, a coating means both the form which covered the ultrafine particle surface completely, or the form with which the clearance gap was vacant.

  The antimony oxide used for the coating is not particularly limited, and examples thereof include antimony chloride, antimony alkoxide, antimony acetate, antimony oxide, antimony potassium tartrate, potassium hexahydroxoantimonate, potassium antimonate, and sodium antimonate. I can do it. The antimony oxide here may be an amorphous oxide, a crystalline oxide, or a hydrated state. Further, it may contain a state in which antimonic acid or a salt thereof is adsorbed and bound to the surface of the nuclear fine particles.

  First, it is coated with antimony oxide. As a method for forming the coating layer, first, an aqueous sol solution of tin-modified rutile-type titanium oxide ultrafine particles is prepared. It is desirable that the concentration of this dispersion is in the range of 0.01 to 50% by weight, preferably 0.1 to 10% by weight as the solid content. If the solid content concentration of the dispersion is less than 0.01% by weight, the productivity is low and not industrially effective, and if the solid content concentration of the dispersion exceeds 50% by weight, the resulting ultrafine particles may become aggregates. There is sex.

  Next, antimony oxide is added to an aqueous sol solution of tin-modified rutile-type titanium oxide ultrafine particles. The amount of antimony oxide added is such that the proportion of antimony oxide in the finally obtained antimony oxide-coated tin-modified rutile titanium oxide ultrafine particles is in the range of 1 to 90% by weight. If it is smaller than this, the light resistance may not be sufficient. If it is larger than this, a sufficient refractive index may not be obtained.

  A solution prepared by dissolving the antimony oxide in water and / or an organic solvent is added to the water-sol solution of the tin-modified rutile-type titanium oxide ultrafine particles while appropriately adjusting the pH and temperature of the solution as necessary. The coating layer can be formed by aging according to the above. After the coating layer is formed, impurities may be removed by washing treatment by ultrafiltration or the like.

  Subsequently, it is coated with silicon oxide. Examples of the silicon oxide used for the coating include silicates such as sodium silicate and potassium silicate. A silicate sol obtained by cation exchange of silicate by a conventionally known method or addition of an acid, or a silicate sol stabilized by adding a base is preferred. The silicon oxide here may be an amorphous oxide, a crystalline oxide, or a hydrated state. Further, a state in which silicic acid, silicic acid oligomer or a salt thereof is adsorbed and bonded to the surface of the core fine particle may be used.

  As a method for forming the coating layer, first, an aqueous sol solution of antimony oxide-coated tin-modified rutile-type titanium oxide ultrafine particles is prepared. It is desirable that the concentration of this dispersion is in the range of 0.01 to 50% by weight, preferably 0.1 to 20% by weight as the solid content. If the solid content concentration of the dispersion is less than 0.01% by weight, the productivity is low and not industrially effective, and if the solid content concentration of the dispersion exceeds 50% 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 solution containing nuclear fine particles (in this case, ultrafine particles of tin-modified rutile titanium oxide coated with antimony oxide). The reaction is performed on the surface of the nuclear fine particles. It is desirable to add dropwise to such an extent that the core fine particle sol solution does not gel over 1 to 100 hours. The pH of the reaction solution is preferably maintained in the range of 7 to 11, and more preferably 8 to 10. When the pH is in this range, polymerization on the surface of the core fine particles proceeds and a dense coating layer can be obtained. If it is larger than this range, the dispersibility of the resulting fine particles may be lowered. If it is smaller than this range, the polymerization may not proceed easily.

  The concentration of silicic acid or silicate after completion of dropping in the reaction solution is preferably 0.01 to 5 wt%, more preferably 0.5 to 2 wt% in terms of silicon oxide. If it is smaller than this, silicic acid or silicate may not be polymerized and a dense coating layer may not be formed. If it is larger than this, the polymerization may proceed excessively and gelation or insoluble matter may be generated.

  The reaction temperature is usually preferably from room temperature to 200 ° C, more preferably from 80 ° C to 180 ° C. If it is lower than this, a dense coating layer may not be formed. If it is higher than this, the fine particles may be gelled.

  After the coating layer is formed, impurities may be removed by washing treatment by ultrafiltration or the like.

  The thus obtained antimony oxide + silicon oxide-coated tin-modified rutile titanium oxide ultrafine particles have a refractive index of antimony oxide + silicon oxide-coated tin-modified rutile titanium oxide ultrafine particles themselves depending on the amount of the coating layer. And light resistance can be adjusted. Light resistance can be imparted and the refractive index can be adjusted from 1.5 to 2.8.

  The amount of antimony oxide and silicon oxide used is not particularly limited, but the coating layer / nucleus weight ratio is preferably 1/99 to 90/10. If it is smaller than this range, the photocatalytic property of titanium oxide cannot be suppressed, and the light resistance may deteriorate. If it is larger than this range, the necessary refractive index may not be obtained.

  The weight ratio between the antimony oxide and the silicon oxide contained in the coating layer is not particularly limited, but is preferably antimony oxide / silicon oxide = 100/1 to 1/50. If it is larger than this, the light resistance may deteriorate. If it is smaller than this, the dispersibility may be deteriorated, or the necessary refractive index may not be obtained.

  In the method for producing composite oxide ultrafine particles of the present invention, the coating layer is formed with antimony oxide and then coated with silicon oxide, or the coating layer is formed with silicon oxide and then coated with antimony oxide. However, when tin-modified rutile-type titanium oxide ultrafine particles are first coated with a silicon compound, dispersion stability may be deteriorated, and therefore it is desirable to perform coating with antimony oxide first. One oxide may be added to the core fine particle sol solution to coat, and after purification such as ultrafiltration, the other oxide may be coated, or it may be added as it is without purification.

  The reaction product obtained as described above may be used as it is as an antimony oxide + silicon oxide-coated tin-modified rutile-type titanium oxide ultrafine particle sol solution, 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 media. The aqueous sol solution in which antimony oxide + silicon oxide-coated tin-modified rutile-type titanium oxide ultrafine particles are dispersed is replaced with an organic solvent such as alcohols such as methanol and cellosolves such as 2-methoxyethanol. It can also be used as an antimony oxide-dispersed tin oxide-modified tin-modified rutile-type titanium oxide ultrafine particle sol solution.

  By modifying the composite oxide ultrafine particles obtained by the present invention, that is, antimony oxide + silicon oxide coated tin-modified rutile titanium oxide ultrafine particles with carboxylic acid, amine, organic silicon oxide, or organic polymer, It can also be used as a surface-modified antimony oxide and silicon oxide-coated tin-modified rutile-type titanium oxide ultrafine particle sol solution. This improves dispersibility and compatibility with organic solvents and resins.

  As the carboxylic acid used for the surface treatment, acetic acid, propionic acid, acrylic acid, methacrylic acid, tartaric acid, glycolic acid and the like are preferably used.

  Further, as the amine used for the surface treatment, propylamine, diisopropylamine, butylamine 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.

  For the organosilicon oxide surface treatment, tetramethoxysilane, methyltrimethoxysilane, (3-glycidoxypropyl) trimethoxysilane, or the like is preferably used. As a treatment method, a sol solution is mixed with a solvent containing an organosilicon oxide, a catalyst is added if necessary, and the mixture is heated for a predetermined time in a range of room temperature to 60 ° C. and then subjected to ultrafiltration, centrifugation, or the like. It is performed by a method such as removing unreacted components in the mixed solution.

  The organic polymer is preferably a polymer having a functional group capable of interacting with the surface of the fine particles such as amino group and carboxylic acid group, such as reaction and adsorption. Polystyrene aminated, chloromethylated, sulfonated, and their derivatives, styrene resins, polymethyl methacrylate, polyethyl acrylate, polyacrylic acid, polyacrylamide and other acrylic resins, vinyl alcohol resins, epoxy Based resins and the like. The surface treatment method may be performed by the method described above.

  The amount of the surface treatment agent to be used is appropriately set in consideration of dispersibility in a binder such as an organic solvent and a resin to be used.

  By this method, ultrafine particles of antimony oxide + silicon oxide-coated tin-modified rutile type titanium oxide 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.

  When the crystal diameter is smaller than 2 nm, there is a possibility that the refractive index originally obtained when used for optical materials, hard coat materials, resin lenses and the like containing these may not be obtained. In addition, when a hard coat film or the like is prepared using a coating solution, scratch resistance and hardness may be insufficient. If it is larger than 20 nm, light scattering may occur. If the average aggregate particle size is larger than 100 nm, the resulting coating film may become cloudy and opaque.

  The minor axis and major axis of the antimony oxide + silicon oxide-coated tin-modified rutile-type titanium oxide ultrafine particles obtained by the present invention are preferably 2 to 20 nm and the average aggregate particle diameter is preferably 10 to 100 nm. When the crystal diameter is smaller than 2 nm, the scratch resistance and hardness are insufficient when a coating 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 size is larger than 100 nm, the resulting coating film may become cloudy and opaque.

  Next, a method for forming a coating film will be described.

In the present invention, the hard coat film is formed from a coating composition containing (A) and (B), which are matrix forming components, as essential components.
The component (A) is composed of an organosilicon compound and at least one silicon-containing substance selected from the group consisting of a hydrolyzate, a partial hydrolyzate and a partial condensate thereof, and the organosilicon compound used is particularly limited. However, an organosilicon compound represented by the following general formula (1) is preferable.

(R ¹ ) _a (R ² ) _b Si (OR ³ ) _(3-ab) (1)
(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 (1) 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 (1) 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.

  In the present invention, among the organosilicon compounds represented by the general formula (1), (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 (2) can also be used together as organosilicon compounds other than the said organosilicon compound.

Si (OR ³ ) ₄ (2)
(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 (2) include the same ^{R 3} in the general formula (1).
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. 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.

  Component (B) is a composite oxide ultrafine particle controlled to have a crystal diameter of 2 to 20 nm and an average aggregate particle diameter of 10 to 100 nm, that is, tin-modified rutile titanium oxide ultrafine particles coated with antimony oxide and silicon oxide. It is a sol liquid dispersed in water. Also, by solvent replacement, 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, toluene, heptane, etc. A sol liquid dispersed in the hydrocarbons.

  In the present invention, the ratio of the solid content (ultrafine particles) of (B) contained in the hard coat film obtained by applying and curing the coating composition is 1 to 80% by weight, preferably 10 to 60% by weight. % Is desirable. If it is smaller than this, the effect of adding ultrafine particles such as an improvement in refractive index is small, and if it is larger than this, there is a possibility that the coating film performance such as lowering of adhesion and occurrence of cracks may be lowered.

  A refractive index of 1.5 to 2.0 can be obtained by the above method, but in order to prevent interference fringes, a range of ± 0.05, preferably a range of ± 0.02, with respect to the refractive index of the substrate. In addition, it is necessary to adjust the refractive index of the coating film. For this reason, when the refractive index of the base material is 1.6 to 2.0, the hard coat film refractive index is changed to 1.5 to 2 by changing the amount of the component (B) added within the above range accordingly. It is necessary to adjust to zero. Naturally, a low refractive index substrate such as a diethylene glycol bis (allyl carbonate) resin substrate having a refractive index of 1.50 can be dealt with by reducing the amount of component (B) to be added.

  In order to correspond to the above base material, the refractive index of the composite oxide ultrafine particles used, that is, the ultrafine particles obtained by coating tin-modified rutile titanium oxide ultrafine particles with antimony oxide and silicon oxide is 2.0 to In order to cope with a substrate having a refractive index of 2.8, particularly a refractive index of 1.70 or more, it is preferably 2.3 to 2.8. For a substrate having a refractive index of less than 1.70, the refractive index can be increased with a small addition amount compared to the conventional metal oxide ultrafine particles. There is no possibility of occurrence of cracks due to too much, decrease in adhesion, and the like.

  The composite oxide ultrafine particles, that is, ultrafine particles obtained by coating tin-modified rutile-type titanium oxide ultrafine particles with antimony oxide and silicon oxide are desirably used after being surface-treated with an organosilicon compound. By reacting the hydroxyl group on the surface of the ultrafine particles with the organosilicon compound, the miscibility with the coating film (condensate of organosilicon compound) is further improved, and the dispersibility in the organic solvent is also improved. In addition, the scratch resistance is improved by the reaction between the particle surface and the organosilicon compound of the matrix component during curing. As the organosilicon compound used, the above-described compounds are used. It is also possible to improve the dispersion stability in an organic solvent by surface treatment with an organic substance such as carboxylic acid or amine.

  As the organosilicon compound used for the surface treatment, organosilicon compounds described in the above general formulas (1) and (2) are preferable, and in particular, (3-glycidoxypropyl) trimethoxysilane, (3-glycidoxy Propyl) methyldiethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, tetramethoxysilane, tetraethoxysilane and hydrolysates thereof are preferably used, and these can be used alone or as a mixture. It is.

  In the surface treatment of the organosilicon compound, the sol solution is mixed with a solvent containing the organosilicon compound, heated in a range of room temperature to 60 ° C. for a certain time, and then the unreacted component in the mixture solution is removed by a method such as ultrafiltration or centrifugation. It is performed by a method such as removal. The amount of the organosilicon compound used is appropriately set in consideration of dispersibility in the organic solvent used in the hard coating composition.

  As the carboxylic acid used for the surface treatment, acetic acid, propionic acid, acrylic acid, methacrylic acid and the like are preferably used.

  Further, as the amine used for the surface treatment, propylamine, diisopropylamine, butylamine and the like are preferably used.

  In the present invention, the organic solvent used in the hard coating composition is not particularly limited. Specifically, for example, alcohols such as methanol, cellosolves such as methyl cellosolve, esters such as ethyl acetate, ethers such as tetrahydrofuran, etc. , Ketones such as acetone, halogen hydrocarbons such as chloroform, hydrocarbons such as toluene and heptane, etc., may be used as a mixture.

  As a method for preparing the hard coating composition of the present invention, the organosilicon compound as the component (A) and the hydrolyzate, partial hydrolyzate or partial condensate solution thereof and the tin-modified rutile type as the component (B) After mixing ultrafine particles of titanium oxide ultrafine particles coated with antimony oxide and silicon oxide with a sol solution dispersed in water or an organic solvent, the above organic solvent may be added as necessary. The organic solvent may be added to the component (A) or the component (B) in advance and then mixed.

  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.

  As the component (B), only ultrafine particles obtained by coating tin-modified rutile titanium oxide ultrafine particles with antimony oxide and silicon oxide are desirable, but they are used in combination with other metal ultrafine particles that are not effective in improving the refractive index. It is also possible. Examples thereof include colloidal silica and antimony oxide colloid.

  Also, various surfactants such as silicon or fluorine can be contained in the coating liquid 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 hard coating composition is applied and cured on a substrate to form a cured film. As a method for applying the cured film on the substrate, a commonly performed method such as a dipping method, a spin method, or a spray method can be applied, but the dipping method and the spin method are preferable efficiently.

  Before applying the above hard coating composition to the substrate, the substrate is chemically treated with acid, alkali, various organic solvents, physical treatment with plasma, ultraviolet rays, etc., detergent treatment with various detergents, Adhesion between the substrate and the cured film can be improved by using a primer treatment using a resin.

  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. The hard coat film thickness is generally about 0.01 to 30 μm, preferably 0.5 to 5 μm. If the film thickness is too thin, the scratch resistance may be low, and if it is too thick, problems such as poor appearance or cracks may occur.

  Similarly, for the primer film, if the difference in refractive index from the substrate is large, interference fringes are generated. In order to eliminate the interference fringes, it is necessary to form a high refractive index primer film equivalent to the lens. The composite oxide ultrafine particles according to the present invention, that is, the composite oxide-coated tin-modified rutile titanium oxide ultrafine particle sol solution Is also suitable as a coating composition for forming such a high refractive index primer film.

  The primer coating composition can be prepared as a primer film by using a resin instead of the organosilicon compound that is a matrix component in the hard coat film.

  The resin to be used is not particularly limited as long as it is a resin that is usually used for primer applications. In the present invention, resins such as polyurethane and polyester are suitable.

  The method for preparing the primer coating composition is not particularly limited. For example, the primer coating is performed by mixing the resin in a solvent, for example, an aqueous dispersion with the ultrafine particles of the present invention or a sol solution thereof. The method of using as a composition is mentioned. Alternatively, it is also possible to add a monomer of the resin or a partial polymer (prepolymer) thereof and a polymerization catalyst to the coating composition and polymerize by heating or the like in the coating film forming stage to form a primer film.

  Furthermore, by forming a primer film between the hard coat film and the substrate, the impact resistance and adhesion of the substrate can be improved.

  The ratio of the solid content of ultrafine particles contained in the primer film is 1 to 80% by weight, preferably 10 to 60% by weight. If it is smaller than this, the effect of adding ultrafine particles such as improvement of the refractive index is small, and if it is larger than this, the coating performance such as adhesion may be lowered.

  Moreover, it can also be used as a photocurable hard coat film by using a photocurable monomer instead of the organosilicon compound which is a matrix component in the coating film.

  In the above, although there is no restriction | limiting in particular as a photocurable monomer, An acrylic compound, a methacryl type compound, or its partial polymer (prepolymer) is suitable.

  The method for preparing the coating composition is not particularly limited. For example, the composite oxide ultrafine particles of the present invention or a sol solution thereof and an initiator are mixed with the compound dissolved in a solvent to form a coating composition. The method to make a thing is mentioned. And in a coating-film formation stage, it can superpose | polymerize by irradiating the light of a required wavelength, and can be set as a cured film.

  The ratio of the solid content of the ultrafine particles contained in the photocurable hard coat film is 1 to 80% by weight, preferably 10 to 60% by weight. If it is smaller than this, the effect of adding ultrafine particles such as improvement of the refractive index is small, and if it is larger than this, the coating performance such as adhesion may be lowered.

  Similarly, the refractive index of 1.50 to 2.0 can be obtained by the above method for the primer film and the photocurable hard coat film, but in order to prevent interference fringes, the refractive index of the substrate is ± 0. It is necessary to adjust the refractive index of the coating film in the range of 05, preferably in the range of ± 0.02. For this reason, when the refractive index of the substrate is 1.50 to 2.0, the coating film refractive index is changed to 1.50 to 2.0 by changing the amount of the component (B) added within the above range accordingly. It is necessary to adjust to.

In the present invention, the antireflection film made of an inorganic oxide vapor deposition film provided on each of the coating films prepared above is not particularly limited, and is well-known TiO ₂ , SiO ₂ , Al ₂ O ₃ , Nb _2. A single-layer or multi-layer antireflection film composed of a vapor-deposited film of an inorganic oxide such as O ₅ can be used.

  The substrate on which the coating composition of the present invention is applied / cured is not particularly limited as long as it is a substrate used for the application of the present invention, for example, an optical member for lenses. The refractive index of a suitable base material is more preferably 1.6 to 1.8, specifically, a polythiourethane-based (refractive index 1.67, 1.70) high refractive index lens or poly Examples thereof include a thioepoxy-based (refractive index: 1.74) ultra-high refractive index lens.

  These ultrafine particles, sol solution, coating composition, and coating film obtained by the present invention are polythiourethane-based (refractive index 1.67, 1.70) high refractive index lenses, and further polythioepoxy-based (refractive index). 1.74) ultra-high refractive index lenses, such as high refractive index coating film of 1.60 or more, particularly high refractive index plastic lenses of 1.70 or more, as well as camera lenses, automotive window glass, plasma displays, liquid crystals It can also be applied as a hard coat film such as a display, an EL display, an optical filter, or an antireflection film.

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

(Preparation of tin-modified rutile titanium oxide ultrafine particles and sol solution)
[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. Take 10g of sol solution of 2.0% by weight of the above solid content, add 200mg of polyvinylpyrrolidone, and spin-coat onto quartz substrate with 10g of ion-exchanged water, dry at 120 ° C, and quickly refract with an ellipsometer. The rate was measured. The refractive index of the solid content was evaluated from the volume fraction of the solid content, and n = 2.72 was obtained.

[Production Example 2]
The same operation as in Example 1 was carried out except that 0.9 g of tin tetrachloride pentahydrate was used in Production Example 1. (Sticking 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 average crystal diameter was 5 nm for the minor axis and 8 nm for the major axis, respectively. It was a rutile type titanium oxide having an average aggregated particle size of 20 nm. The element molar ratio of Sn / Ti was 0.06. The refractive index of the solid content was evaluated in the same manner as in Production Example 1, and n = 2.65 was obtained.

(Preparation of antimony oxide + silicon oxide-coated tin-modified rutile titanium oxide ultrafine particle sol solution)

  After adding 20 g of potassium hydroxide to 240 g of an aqueous suspension of 30 g of antimony trioxide and heating to 70 ° C., 30 g of 35 wt% aqueous hydrogen peroxide was added dropwise to give a 10 wt% antimonate aqueous solution in terms of antimony pentoxide. Prepared. The pH was 8.3.

  Ion exchange water was added to water glass (containing 35% by weight of silicon oxide) to give a 3% by weight aqueous solution in terms of silicon oxide.

  The aqueous solution was passed through a cation exchange resin to prepare a silicate sol solution having a pH of 2.6. Subsequently, a 10 wt% aqueous sodium hydroxide solution was added dropwise until pH = 8.2 to obtain a 2 wt% stabilized silicate sol solution.

  66 g of the above antimonate aqueous solution was added to 1500 g of the 2 wt% tin-modified rutile-type titanium oxide ultrafine particle sol solution prepared in Production Example 1, and heated at 85 ° C. for 8 hours. The solution was purified by ultrafiltration to obtain a 4 wt% antimony oxide-coated tin-modified rutile-type titanium oxide ultrafine particle sol solution.

  2500 g of this antimony oxide-coated tin-modified rutile titanium oxide ultrafine particle sol solution was heated to 90 ° C. While removing the water under reduced pressure and keeping the liquid volume at 2500 g, 630 g of the above-mentioned stabilized silicate sol solution was added dropwise over 90 hours and further heated for 3 hours. Purification was performed by ultrafiltration to prepare a 10 wt% antimony oxide + silicon oxide-coated tin-modified rutile type titanium oxide ultrafine particle sol solution. After elemental analysis by inductively coupled plasma method after drying with hot air at 120 ° C. for 2 hours, the weight ratio of antimony oxide / silicon oxide / tin modified titanium oxide in terms of oxide = 0.12 / 0.9 / 1. there were. The solvent was converted to methanol by a rotary evaporator to obtain a 20 wt% methanol-dispersed sol solution.

  A 20 wt% methanol-dispersed sol solution was prepared in the same manner as in Example 1 except that the tin-modified rutile-type titanium oxide ultrafine particle sol solution prepared in Production Example 2 was used.

(Preparation of coating solution)

  To 15 g of (3-glycidoxypropyl) trimethoxysilane, 3.5 g of 0.001N 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, 5.3 g of the aforementioned (3-glycidoxypropyl) trimethoxysilane partial hydrolyzate solution was added to 9.3 g of the methanol sol solution (total solid concentration 20% by weight) obtained in Examples 1 and 2. Furthermore, 50 mg of aluminum acetylacetonate and 10 mg of a surfactant (manufactured by Nippon Unicar Co., Ltd .: L7604) were added as a curing agent and stirred to prepare a coating solution.

(Creation of hard coat film)

  A resin lens having a refractive index of 1.74 (manufactured by Mitsui Chemicals, Inc .: MR-1.74) was prepared, immersed in an aqueous sodium hydroxide solution, subjected to ultrasonic cleaning, and dried. Each coating liquid obtained in Example 3 was applied to this base material by a spin coating method, followed by heat treatment at 90 ° C. for 30 minutes and then at 120 ° C. for 2 hours to cure the coating film. The thickness of the hard coat film thus obtained was 2 μm.

(Preparation of primer coating solution)

  Methanol sol solution (solid content 20% by weight) 9 prepared in Example 2 in 5.3 g of an aqueous dispersion of polyurethane resin (total solid content 30% by weight) (manufactured by Daiichi Kogyo Seiyaku Co., Ltd .: Superflex 150) 9 .3 g was added, and ethyl cellosolve was further added to prepare a coating solution having a total solid content of 8% by weight.

(Preparation of primer film)

  A resin lens having a refractive index of 1.74 (manufactured by Mitsui Chemicals, Inc .: MR-1.74) was prepared, immersed in an aqueous sodium hydroxide solution, subjected to ultrasonic cleaning, and dried. The coating liquid obtained in Example 5 was applied to this substrate by a spin coating method, followed by heating and drying at 83 ° C. for 1 hour and then at 120 ° C. for 30 minutes to form a coating film. The thickness of the coating film thus obtained was 1 μm.

(Preparation of hard coat film with primer film)

  Using the methanol sol solution prepared in Example 2, a hard coat film was formed on the eyeglass lens substrate on which the primer film was applied in Example 6 in the same manner as in Examples 3 and 4.

(Preparation of photocurable coating solution)

  To 15 g of ethyl cellosolve, 1.6 g of a urethane acrylate oligomer (manufactured by Kyoeisha Chemical Co., Ltd .: UA306I) and 0.05 g of a polymerization initiator (manufactured by Ciba Specialty Chemicals: Darocur 1173) were added. Next, 9.3 g of the methanol sol solution (total solid content 20% by weight) obtained in Example 2 was added to prepare a coating solution.

(Creation of photocurable coating film)

  A resin lens having a refractive index of 1.74 (manufactured by Mitsui Chemicals, Inc .: MR-1.74) was prepared, immersed in an aqueous sodium hydroxide solution, subjected to ultrasonic cleaning, and dried. The coating liquid obtained in Example 8 was applied to the base material by a spin coating method, and irradiated with a high pressure mercury lamp (160 W / cm) to cure the coating film. The thickness of the coating film thus obtained was 2 μm. No interference fringes were seen.

[Comparative Example 1]
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 a titanium oxide anatase type having an average of 5 nm on both the minor axis and the major axis. The refractive index of the solid content was evaluated in the same manner as in Production Example 1, and n = 2.52 was obtained. The solvent was converted to methanol by a rotary evaporator to obtain a 20 wt% methanol-dispersed sol solution.

(Preparation of antimony oxide + silicon oxide-coated anatase-type titanium oxide ultrafine particle sol solution)
[Comparative Example 2]
Antimony oxide + silicon oxide-coated anatase-type titanium oxide ultrafine particle sol in the same manner as in Example 1 except that the anatase-type titanium oxide ultrafine particle sol solution having a solid content of 2.0% by weight prepared in Comparative Example 1 was used. A liquid was prepared.

(Preparation of coating solution)
[Comparative Example 3]
A coating solution was prepared in the same manner as in Example 3 except that the sol solution prepared in Comparative Examples 1 and 2 was used.

(Creation of hard coat film)
[Comparative Example 4]
A hard coat film was prepared in the same manner as in Example 4 except that the above coating solution was used.

  The dispersion stability of the interference fringes, scratch resistance, light resistance, and coating solution was evaluated for the lens substrate on which the hard coat film was applied by the above method, as shown below. The results are shown in Table 1.

(A) Interference fringes: An optical member having a hard coat film was visually determined under a fluorescent lamp. Judgment criteria are as follows.
○ ... Interference fringes are almost invisible.
△ ... looks a little × ... looks pretty

(B) Scratch resistance: The surface was rubbed with a steel wool (# 000) under a load of 500 g, and the degree of damage was visually evaluated. Judgment criteria are as follows.
○… Almost scratches △… Slightly scratches ×… Severely scratches

(C) Light resistance test: The substrate with hard coat film obtained was not peeled in an adhesion test after irradiation for 300 hours by a solar simulator (Type: sss-252161-ER manufactured by USHIO INC.), And The one without yellowing was marked as ◯. The adhesion between the base material and the hard coat 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) Dispersion stability: The changes when the prepared coating solution was stored at room temperature for one month were evaluated by the following indices.
○ ... No change △ ... Increased viscosity × ... Gelled

(E) Measurement of refractive index of coating 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 to obtain an automatic wavelength scanning ellipsometer M-150 (JASCO Corporation )).

  As can be seen from the above results, high refractive index and fine particle photocatalytic properties that cannot be obtained by using anatase type titanium oxide by coating rutile type titanium oxide ultrafine particles with antimony oxide + silicon oxide effectively Suppressed composite oxide ultrafine particles have been obtained, and a coating film having a high refractive index and excellent light resistance without interference fringes has been obtained.

  The composite oxide ultrafine particles obtained by the present invention, that is, the composite oxide-coated tin-modified rutile type titanium oxide ultrafine particles, the sol solution, and the coating composition, are applied to the base material when they are scratch resistant, surface hardness, abrasion resistant. It is possible to provide a high refractive index hard coat film of a high refractive index plastic lens that has good wear, adhesion, transparency, heat resistance, light resistance, weather resistance, ultraviolet shielding properties, etc., and does not generate interference fringes. Furthermore, as a high refractive index agent, light reflecting agent, ultraviolet absorber, etc., optical lenses (glass lenses, pickup lenses in information recording equipment such as CDs and DVDs, lenses for photographing equipment such as digital cameras), optical prisms, Optical waveguides, optical fibers, thin film moldings, optical adhesives, materials for high refractive optical members such as optical semiconductor encapsulating materials, plastic deterioration prevention additives, cosmetic additives, automotive window glass, plasma displays, There is utility that an optical member such as a liquid crystal display, an EL display, and an optical filter, and a product such as a metal material, a ceramic material, a glass material, and a plastic material for refractive index adjustment can be provided.

Claims (21)

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. A core fine particle of rutile type titanium oxide ultrafine particles having a Sn / Ti composition molar ratio of 0.001 to 0.5 and a short axis of crystal diameter and a long axis of 2 to 20 nm, and containing antimony oxide coating layer to be coated is composed of a silicon oxide target Kutsugaeso covering the antimony oxide coating layer, the minor axis of the crystal diameter, the composite oxide ultrafine particles long axis is 2~20nm Coating composition. Weight of the weight ratio of the coating layer / core of the composite oxide ultrafine particles is 1/99 to 90/10, antimony oxide / silicon oxide contained in the silicon oxide coating layer and the antimony oxide coating layer The coating composition according to claim 1 , wherein the ratio is 100/1 to 1/50. The coating composition according to claim 1 or 2, wherein the composite oxide ultrafine particles have a refractive index of 1.5 to 2.8. The composite oxide composed of ultra-fine particles, the average coating composition according to claim 1, aggregated particle diameter contains crystal ultrafine particles agglomerates is 10 to 100 nm. The coating composition according to any one of claims 1 to 4, wherein the composite oxide ultrafine particles contain a sol solution dispersed in water or an organic solvent.   The coating composition according to any one of claims 1 to 5, comprising at least one selected from an organosilicon compound, a hydrolyzate thereof and a condensate thereof.   A hard coat film obtained by curing using the coating composition according to claim 6.   The coating composition according to any one of claims 1 to 5, comprising one or more resins or resin monomers.   A primer film obtained by curing using the coating composition according to claim 8.   The coating composition according to any one of claims 1 to 5, comprising at least one photocurable monomer.   A hard coat film obtained by curing using the coating composition according to claim 10.   The hard coat film according to claim 7, which has a refractive index of 1.5 to 2.8.   The primer film according to claim 9, which has a refractive index of 1.5 to 2.8.   The hard coat film according to claim 11, having a refractive index of 1.5 to 2.8.   A substrate on which the hard coat film according to claim 7 or 12 is applied.   A substrate provided with the primer film according to claim 9 or 13.   A substrate provided with the hard coat film according to claim 11.   A base material obtained by applying the hard coat film according to claim 7 or 12 on the primer film according to claim 9 or 13.   The base material according to claim 15, wherein the base material has a refractive index of 1.5 to 2.0.   The substrate according to any one of claims 15 to 19, wherein the substrate is a polythiourethane resin or a polythioepoxy resin.   A base material obtained by further applying an antireflection film on the base material according to any one of claims 15 to 20.