Coating solution for forming titanium dioxide-containing films

Abstract

To provide coating enabling formation of a coated film which has high light resistance, high transparency and uniform thickness even including titanic oxide.SOLUTION: Coating liquid of the invention includes: first surface processing particles in which first organic silicon compounds are coupled to surfaces of particles including titanic oxide; second organic silicon compound; a binder component; and organic solvent. The titanic oxide has rutile type crystal structure, and 3 to 10 mass% of first silicon compound SiX4 in terms of SiO2 is coupled to particle surfaces including titanic oxide. The second silicon compound R-(CH2)nSiX3 or a hydrolysate thereof is included in an amount of 0.3 to 2.0 in a molar ratio (second organic silicon compound / first organic silicon compound) to the first silicon compound, and in solid, silicon derived from the first and second silicon compounds is included in an amount of 2 to 20 mass% in terms of SiO2. (X is at least one selected from an alkoxy group, hydroxy group, and halogen, R is an acrylic group and methacrylic group, n is an integer from 1 to 8.) The organic solvent is a mixed solvent including; a low boiling point organic solvent S1 having a boiling point less than 95°C; and a high boiling point organic solvent S2 having a boiling point higher than or equal to 95°C, a mass ratio of them (MS1 / MS2) is 85 / 15 to 50 / 50. In addition, a mass ratio (MF / MB) between an inorganic oxide component (F) and a binder component (B) included in the first surface processing particles and in the second organic compound, is 45 / 55 to 95 / 5.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a coating solution for forming a titanium dioxide-containing film. [Background technology]

[0002] High refractive index films have traditionally been used in a variety of applications, including displays for smartphones and televisions, and lenses for eyeglasses. The properties required of such high refractive index films include, of course, a high refractive index, high transparency, uniform film thickness (no unevenness in the film), and the ability to maintain their performance even after prolonged exposure to light (high light resistance).

[0003] Generally, methods for obtaining high refractive index films can be broadly classified into two types: dry methods, such as vacuum deposition or sputtering, for forming films using metal oxides with high refractive index, such as titanium dioxide; and wet methods, in which a coating solution containing inorganic oxide particles (fillers) with high refractive index, binder components, and organic solvents is applied to a substrate, dried, and then cured to form the film.

[0004] While the dry process yields dense and rigid films, it requires processing under vacuum, limiting the area of ​​film that can be fabricated at one time, raising concerns about cost and productivity.

[0005] On the other hand, the wet process allows for film formation under atmospheric pressure and offers excellent continuous production capabilities, which is why it has become widely used in recent years.

[0006] Here, a coating composition is disclosed that contains composite oxide fine particles, in which the surface of rutile-type titanium oxide particles having a refractive index of 1.5 to 2.8 is coated with a metal oxide raw material (such as sodium silicate or potassium silicate) that has excellent light resistance, a curable binder, and an organic solvent (see, for example, Patent Document 1).

[0007] The film formed from such a coating composition has a high refractive index derived from titanium dioxide, and because the titanium dioxide particles are coated with a highly light-resistant inorganic oxide, the photocatalytic activity is reduced, resulting in a coating film with excellent light resistance.

[0008] Furthermore, a coating agent is disclosed that includes core-shell particles, in which inorganic oxide particles are coated with a hydrolysate of a tetrafunctional organosilicon compound (tetraethoxysilane) on the surface of rutile-type titanium dioxide particles with excellent ultraviolet absorption capabilities, and a silicon resin (see, for example, Patent Document 2). The film obtained by applying this coating agent contains a large amount of silicon compounds with excellent light resistance, so even if photocatalytic activity originating from titanium dioxide occurs, the film deteriorates less. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2006-342311 [Patent Document 2] International Publication No. 2018 / 096914 [Overview of the project] [Problems that the invention aims to solve]

[0010] The coating film made from the coating composition described in Patent Document 1 contains sodium derived from sodium silicate. Such impurities cause aggregation of inorganic oxide particles and binder components contained in the paint, reducing the transparency and uniformity of the film thickness when the film is formed. Furthermore, although it has been exemplified that the surface of titanium oxide particles coated with sodium silicate is treated with an organosilicon compound such as methyltrimethoxysilane to improve dispersibility in organic solvents and curable binders, the organosilicon compound's side chain is a treatment agent with a low number of carbon atoms, such as a methyl group, resulting in poor compatibility with organic solvents and binders, causing particle aggregation during film formation. As a result, in addition to reduced transparency, a film with a uniform thickness cannot be obtained.

[0011] The coating agent described in Patent Document 2 has a high proportion of silicon oxide in the film and exhibits excellent light resistance, but since it does not suppress the photocatalytic activity of titanium dioxide itself, there is a concern that the binder component may deteriorate with long-term use.

[0012] Therefore, the object of the present invention is to provide a coating that has high light resistance even when containing titanium dioxide, and can form a coating film with high transparency and uniform film thickness. [Means for solving the problem]

[0013] The coating solution of the present invention comprises first surface-treated particles in which a first organosilicon compound is bonded to the surface of titanium dioxide-containing particles, a second organosilicon compound, a binder component, and an organic solvent. The titanium dioxide has a rutile-type crystalline structure, and the first organosilicon compound "SiX4" is bonded to the surface of the titanium dioxide-containing particles in an amount of 3 to 10% by mass in terms of SiO2, and the second organosilicon compound "R-(CH2) n The "SiX3" or its hydrolysate is present in a molar ratio (second organosilicon compound / first organosilicon compound) of 0.3 to 2.0 relative to the first organosilicon compound, and the solid content contains 2 to 20% by mass of silicon derived from the first organosilicon compound and the second organosilicon compound in terms of SiO2 (X is at least one selected from alkoxy groups, hydroxyl groups, and halogens; R is an acrylic group and a methacrylic group; n is an integer from 1 to 8). Furthermore, the organic solvent is a mixed solvent containing a low-boiling point organic solvent (S1) with a boiling point below 95°C and a high-boiling point organic solvent (S2) with a boiling point of 95°C or higher, and their mass ratio (M S1 / M S2 The ratio is 85 / 15 to 50 / 50. Furthermore, the mass ratio (M) of the inorganic oxide component (F) and the binder component (B) contained in the first surface-treated particles and the second organosilicon compound is F / M B ) is 45 / 55 to 95 / 5.

[0014] The film formed from such a coating solution has high light resistance because the photocatalytic activity of titanium dioxide is reduced by the first organosilicon compound bound to the particle surface containing titanium dioxide. In addition, the side chain "R-(CH2)" of the second organosilicon compoundn The presence of "-" improves the dispersibility of particles in the coating solution and film, allowing them to disperse within the system without aggregation. Furthermore, the inclusion of a mixed solvent regulates the drying rate of the film, resulting in a uniform film formation. Moreover, because the mixing ratio of the film-forming components (first surface treatment particles, second organosilicon compound, and binder component) is appropriate, a highly transparent and uniform film with no unevenness in thickness is obtained. In short, a titanium dioxide-containing coating solution is obtained that achieves high refractive index, high lightfastness, high transparency, and uniform film thickness. [Modes for carrying out the invention]

[0015] The titanium dioxide-containing coating solution according to the present invention contains titanium-containing particles whose surfaces are modified with two types of organosilicon compounds, a binder, and two types of organic solvents having different boiling points. Using such a coating solution, it is possible to form a film that has high light resistance, high transparency, and uniformity (less film thickness variation) even though it contains titanium dioxide.

[0016] [Titanium dioxide-containing particles] Titanium dioxide crystal structures are classified into rutile, anatase, and brookite types. The titanium dioxide in the particles used in this invention has a rutile crystal structure, which is desirable from the viewpoint of high refractive index and high light resistance.

[0017] Particles containing titanium dioxide having a rutile-type crystal structure may contain other elements as long as they contain the element Ti. For example, a particle dispersion containing titanium dioxide as described in Japanese Patent Publication No. 2009-155496 can be used.

[0018] [Organosilicon compounds] On the surface of the titanium oxide-containing particles, a first organosilicon compound is bonded. The first organosilicon compound is represented by the general formula "SiX4". X is at least one selected from an alkoxy group, a hydroxyl group, and a halogen. When such a first organosilicon compound binds to the surface of the titanium oxide-containing particles, degradation of the binder component due to the photocatalytic activity of titanium oxide is suppressed, and the second organosilicon compound described later is likely to bind to the particle surface. The first organosilicon compound covers the particles by hydrolysis of some or all of X and binding to the hydroxyl groups on the particle surface. The coating in the present invention does not require the organosilicon compound to completely cover the entire particle surface. X is preferably an ethoxy group.

[0019] The first organosilicon compound bonded to the surface of the titanium oxide-containing particles is 3 to 10% by mass as SiO2 with respect to 100 parts by mass of the titanium oxide-containing particles. When the particles are coated within the above range, the first organosilicon compound can sufficiently cover the particle surface while maintaining the high refractive index derived from titanium oxide, and the second organosilicon compound is likely to bind. In addition, the photocatalytic activity derived from titanium oxide can be suppressed.

[0020] [Second organosilicon compound] The second organosilicon compound is represented by the general formula "R-(CH2) n SiX3" (X is at least one selected from an alkoxy group, a hydroxyl group, and a halogen; R is an acrylic group or a methacrylic group; n is an integer of 1 to 8). Such a second organosilicon compound binds to the particle surface by a hydrolysis polycondensation reaction and improves the dispersibility of the particles (the first surface-treated particles to which the second organosilicon compound is bound are referred to as second surface-treated particles). In addition, due to the presence of the side chain "R-(CH2) n -", the compatibility (wettability) with the binder component is improved, and even when the concentration of the particles containing titanium oxide and the binder component increases during the process of drying the coating liquid during film formation, drying occurs in a uniform state without layer separation. As a result, a transparent and uniform film can be obtained without particle aggregation. In addition, the photocatalytic activity derived from titanium oxide can be suppressed. The preferred value of n is 3.

[0021] The above-mentioned secondary organosilicon compound is present in a molar ratio (first / second) of 0.3 to 2.0 relative to the first organosilicon compound coating the particles. When present in the coating solution within this range, the secondary organosilicon compound binds to the silanol groups of the first organosilicon compound coating the particle surface, resulting in uniform dispersion of the particles in the dispersion, coating solution, and film. Furthermore, even if the solid content concentration increases during drying after coating, the particles do not aggregate, and the film surface becomes uniform. In addition, the "acrylic group or methacrylic group" contained in the secondary organosilicon compound reacts with the reactive groups of the binder component during curing, forming bonds that improve particle packing and contribute to the uniformity of the film surface. Free secondary organosilicon compounds that are not bound to the particle surface may also be present in the coating solution. Preferably, the amount is 0.4 to 1.9, more preferably 0.4 to 1.5.

[0022] [Binder components] Binder components include photocurable monomers that harden upon UV irradiation and thermosetting monomers that harden upon heat. However, in this invention, considering application to organic films with low heat resistance, photocurable monomers are preferred. The photocurable monomer is not particularly limited as long as it can be cured by UV irradiation, but monomers having an acrylic group or a methacrylic group are preferably used from the viewpoint of reactivity and compatibility with the surface of the second surface-treated particles.

[0023] The above monomers may be used individually or in combination of two or more. When used individually, it is preferable that the monomer contains three or more polymerizable groups. When two or more are mixed, it is preferable to use at least one monomer that has at least three polymerizable groups.

[0024] [Solid content concentration] The solid content concentration in the coating solution is preferably 1 to 10% by mass. Here, the solid content in the coating solution refers to components that do not evaporate even when the coating solution is heated at 200°C for 3 hours. When the solid content concentration is within the above range, the stability of the coating solution is improved and the pot life is extended. More preferably, it is 1 to 5% by mass.

[0025] [Film forming component] The mass ratio (M F / M B ) of the inorganic oxide component (referred to as filler "F") and the binder component (referred to as binder "B") contained in the first surface treatment particles and the second organosilicon compound is 45 / 55 to 95 / 5. When the mass ratio is within this range, a transparent film with a uniform film thickness can be obtained without impairing the high refractive index derived from titanium oxide. More preferably, it is 50 / 50 to 80 / 20. The inorganic oxide component contained in the first surface treatment particles and the second organosilicon compound refers to a component that does not volatilize even when heated at 1000°C for 1 hour.

[0026] Silicon derived from the first and second organosilicon compounds accounts for 5 to 20% by mass in terms of SiO2 in the solid content of the coating solution. If it is less than 5% by mass, the amount of SiO2 coating the particles containing titanium oxide is not sufficient, so the photocatalytic activity of titanium oxide cannot be suppressed, and as a result, the light resistance of the film decreases. On the other hand, if it exceeds 20% by mass, the content of titanium oxide in the film relatively decreases, and the film refractive index decreases. Preferably, it is 5.7 to 14.5% by mass, more preferably 5.7 to 10.0%.

[0027] [Organic solvent] The organic solvent is a mixed solvent containing a low-boiling organic solvent (S1) with a boiling point of less than 95°C and a high-boiling organic solvent (S2) with a boiling point of 95°C or higher, and the mixing ratio (S1 / S2) is 85 / 15 to 50 / 50. After applying the coating solution containing the organic solvent, regardless of the curing conditions, there is a step of evaporating the solvent in the coating solution. At that time, if the amount of the low-boiling organic solvent is large, the coating solution evaporates at once, and the uniformity of the film decreases due to convection in the film and the influence of condensed water due to the latent heat of vaporization of the solvent. On the other hand, if the high-boiling organic solvent is large, the solvent tends to remain in the film and the uniformity of the film decreases. With the above mixed solvent, first, the low-boiling organic solvent evaporates, and the coating solution is concentrated to a certain concentration, and then the high-boiling organic solvent evaporates slowly, so that a uniform and transparent film can be obtained. The boiling point of the preferred high-boiling solvent is 95 to 150°C, more preferably 110 to 150°C.

[0028] The surface tension of the coating of the present invention is preferably 20 to 25 mN / m. When the surface tension is within this range, it spreads uniformly when applied to a substrate, resulting in a smooth film.

[0029] [Other ingredients] Other components (such as photopolymerization initiators and leveling agents) are added to the coating solution as needed. Known photopolymerization initiators can be used. In this case, it is preferable that the photopolymerization initiator is contained in an amount of 1 to 10% by mass relative to the binder component. If it is less than 1% by mass, the curing reaction will not proceed easily, and the hardness will tend to decrease. If it is more than 10% by mass, the proportion of particles and binder components in the film will decrease, and the hardness and abrasion resistance of the film will tend to decrease. A photopolymerization initiator content of 4 to 8% by mass is more preferable.

[0030] A leveling agent may be added to the coating solution to adjust the wettability with the substrate and the leveling properties of the film surface. Preferably, the leveling agent is present in an amount of 5% by mass or less of the solid content of the coating solution, and more preferably substantially absent. By substantially omitting the leveling agent, it becomes easier to form a film on the titanium oxide-containing film made from the coating solution of the present invention. Examples of leveling agents include acrylic, acrylic silicone, silicone, and fluorine-based leveling agents.

[0031] [Application Method] A film-coated substrate can be manufactured by forming a film on a substrate using the above-described coating solution. Specifically, a film-coated substrate is obtained by applying the coating solution to the substrate and then drying and curing the coating solution. Coating methods include spin coating, bar coating, gravure coating, slit coating, etc.

[0032] [Base material] Examples of substrates to which the coating solution of the present invention is applied include glass, plastic films, and films with a hard coat. The substrate used can be selected depending on the application. Examples of plastic films include polyethylene terephthalate (PET), triacetylcellulose (TAC), acrylic, polycarbonate, and cycloolefin polymer. These substrates may have a hard coat (HC) film formed on them. By forming a titanium oxide-containing film on the HC film, the hardness and scratch resistance of the film-coated substrate are increased.

[0033] [Titanium oxide-containing film] Using the above-described coating solution, a titanium dioxide-containing film is formed directly or indirectly on the substrate. The titanium dioxide-containing film is mainly composed of surface treatment particles and a binder component. The titanium dioxide-containing coating solution of the present invention can form a highly transparent, uniform film with minimal unevenness, and has a low contact angle with water, even without the addition of a leveling agent. Therefore, it is useful for anti-reflective films that further provide a low refractive index layer on top of the film of the present invention.

[0034] In other words, the contact angle of the titanium oxide-containing film of the present invention with respect to water is preferably 90° or less. When the contact angle with respect to water is 90° or less, when a film is formed on top of the titanium oxide-containing film, the wettability with the paint applied to the upper layer is good, and a uniform film can be obtained. More preferably, it is 70° or less.

[0035] The average surface roughness (Ra) of the titanium dioxide-containing film is preferably less than 1 nm. Ra indicates the surface irregularities of the film; the larger this value, the greater the surface irregularities. In other words, a high Ra value results in an uneven film thickness, causing light to scatter in the irregular areas, and consequently reducing transparency.

[0036] The thickness of the titanium dioxide-containing film is appropriately selected depending on the application, but when used in an anti-reflective film obtained by forming a low refractive index film on top, a thickness of 50 to 150 nm is preferable. A film thickness within this range yields a film with high transparency and excellent anti-reflective properties. [Examples]

[0037] [Example 1] The following describes specific embodiments of the present invention.

[0038] <Preparation of first surface-treated particles> First, a titanium dioxide-containing particle aqueous dispersion was prepared. The titanium dioxide-containing particle aqueous dispersion can be prepared by known methods. In this example, referring to Example 6 of Japanese Patent Application Publication No. 2009-155496, an aqueous dispersion of core-shell particles (inorganic oxide concentration 10% by mass) was prepared, in which particles containing rutile-type titanium dioxide formed the core and a coating layer of a Si-Zr composite oxide was provided. A cation exchange resin was added to 117.0 g of this aqueous dispersion to perform dealkalization. The ion exchange resin was separated and added to a mixed solution of 8.96 g of tetraethoxysilane (manufactured by Tama Chemical Co., Ltd.) and 126.0 g of methanol. After heating and stirring for 5 hours (50°C), it was cooled to room temperature and the solvent was replaced from water to methanol using an ultrafiltration membrane. Subsequently, by concentration, 71.3 g of a first surface-treated particle dispersion (inorganic oxide component concentration 20% by mass) was obtained, in which a primary organosilicon compound was bonded to the surface of the titanium dioxide-containing particles.

[0039] (Amount of organosilicon compounds bonded) The first surface-treated particle dispersion was dried at 100°C for 10 minutes to obtain the first surface-treated particle powder. This powder was heated with a burner to carbonize the organic components, then sodium peroxide and sodium hydroxide were added and dissolved. Sulfuric acid and hydrochloric acid were then added to prepare the sample. The Si concentration in this sample was measured using an ICP emission spectrometer ICP-OES (ICPS-8100, Shimadzu Corporation), and the Si content was calculated and then converted to SiO2 content.

[0040] Similarly, the SiO2 content of the titanium dioxide-containing particle dispersion was measured, and the difference in SiO2 content between the titanium dioxide-containing particles and the first surface-treated particles was defined as the amount of the first organosilicon compound bonded.

[0041] <Preparation of second surface-treated particles> 80.0 g of the first surface-treated particle dispersion was mixed with 4.9 g of 3-methacryloxypropyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd.: KBM-503), and then heated and stirred at 50°C for 18 hours. Subsequently, the solvent was replaced from methanol to propylene glycol monomethyl ether (PGME) using a rotary evaporator to obtain 71.9 g of the second surface-treated particle dispersion with an inorganic oxide component concentration of 20% by mass.

[0042] (Molar ratio of first organosilicon compounds and second organosilicon compounds) The molar ratio (second / first) of the second organosilicon compound to the first organosilicon compound was calculated from the number of moles calculated from the amount of the first organosilicon compound bonded as described above, and from the number of moles calculated from the amount of the second organosilicon compound added during the preparation of the second surface-treated particles.

[0043] <Preparation of titanium dioxide-containing coating solution> To 10.24 g of the second surface treatment particle dispersion, 0.09 g of 1,6-hexadiol diacrylate (manufactured by Tomoe Engineering Co., Ltd.: SR-238F) and 0.81 g of dipentaerythritol hexaacrylate (manufactured by Kyoeisha Chemical Co., Ltd.: DPE-6A) were mixed as binder components, 0.05 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (manufactured by IGMResins B.V.: OMNIRAD® TPO-H) as a photopolymerization initiator, and 79.67 g of isopropyl alcohol (IPA) and 9.12 g of PGME were added as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 3% by mass. The surface tension of this coating solution was 22 mN / m. The surface tension of the paint was measured using the plate method (Wilhelmy method) with an automatic surface tension meter (Kyowa Interface Science Co., Ltd.: DY-300) at a temperature of 25°C, using a titanium dioxide-containing coating solution.

[0044] <Preparation of substrates with titanium oxide-containing film> A titanium dioxide-containing coating solution was applied to a TAC film (manufactured by Fujifilm Corporation: FT-80UL, thickness: 80 μm, refractive index: 1.49) with a hard coat layer (manufactured by JGC Catalysts & Chemicals Co., Ltd., ELCOM HC-A) using the bar coater method (#4), dried at 80°C for 120 seconds, and then subjected to a 400 mJ / cm² atmosphere under N2 conditions. 2 A substrate coated with a titanium dioxide film was obtained by curing it with ultraviolet light. The film thickness of the titanium dioxide-containing substrate was approximately 70-130 nm. Substrates coated with titanium dioxide films were prepared similarly in other examples and comparative examples.

[0045] "evaluation" The titanium dioxide-containing film-coated substrate was evaluated using the following method. The results for other examples and comparative examples are also shown in Table 2.

[0046] (exterior) The surface of the titanium dioxide-containing film-coated substrate was visually observed and evaluated according to the following criteria.

[0047] <Evaluation Criteria> No surface defects such as whitening, streaks, unevenness, or bleed-out were observed: ◎ Almost no cosmetic defects such as whitening, streaks, unevenness, or bleed-out were observed on the surface: ○ Slight surface defects such as whitening, streaks, unevenness, and bleed-out were observed: △ Appearance defects such as whitening, streaks, unevenness, and bleed-out were clearly observed on the surface: ×

[0048] (Average roughness R a ) The average surface roughness (Ra) of the titanium oxide-containing film-coated substrate and the anti-reflective film-coated substrate was measured at a 10 μm square using an atomic force microscope (AFM) (Bruker Corporation: Dimension 3100).

[0049] (Refractive index) A titanium dioxide-containing coating solution was spin-coated onto a dummy silicon wafer (manufactured by Matsuzaki Seisakusho Co., Ltd.: 6-inch dummy wafer (P-type), thickness: 625 μm), dried at 80°C for 120 seconds, and then subjected to 400 mJ / cm² under an N2 atmosphere.2 A titanium dioxide-containing film was formed by curing it with ultraviolet light and used as a sample for measuring the refractive index of the film. The obtained sample was measured using a spectroscopic ellipsometer (SE-2000, manufactured by Nippon Semilab Co., Ltd.), and the refractive index at a wavelength of 550 nm was taken as the refractive index of the titanium dioxide-containing film of the present invention. The thickness of the titanium dioxide-containing film was approximately 100 nm.

[0050] (Lightfastness) Samples prepared using the same method as described above for refractive index measurement were irradiated with ultraviolet light at 100 mW for 6 hours using a metal halide lamp type lightfastness tester (Iwasaki Electric Co., Ltd.: iSuper UV Tester, SUV-F11). The film thickness was then measured using a spectroscopic ellipsometer, and the lightfastness was evaluated from the percentage reduction in film thickness after the test. The percentage reduction in film thickness was calculated using the formula (1 - film thickness after UV irradiation / film thickness before irradiation) × 100 (%). Film thickness reduction rate after lightfastness test is less than 5%: ◎ Film thickness reduction rate after lightfastness test is 5% or more but less than 10%: ○ Film thickness reduction rate after lightfastness test is 10% or more: ×

[0051] (contact angle) A titanium dioxide-containing coating solution was applied to a TAC film (Fujifilm Corporation: FT-80UL, thickness: 80 μm, refractive index: 1.49) using the bar coater method (#4), dried at 80°C for 120 seconds, and then subjected to a 400 mJ / cm² atmosphere under N2 conditions. 2 A film was formed by curing the titanium dioxide-containing material by irradiation with ultraviolet light, and this was used as a sample for contact angle measurement. The thickness of the titanium dioxide-containing film was approximately 70-130 nm. The contact angle of the obtained sample with respect to a 5 μL droplet of water was measured using a fully automated contact angle meter (Kyowa Interface Science Co., Ltd.: DM-701).

[0052] [Example 2] A titanium dioxide-containing coating solution was obtained in the same manner as in Example 1, except that 1.6 g of 3-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-503) was added to 80.0 g of the first surface treatment particle dispersion. The surface tension of this coating solution was 22 mN / m.

[0053] [Example 3] A titanium dioxide-containing coating solution was obtained in the same manner as in Example 1, except that 6.5 g of 3-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-503) was added to 80.0 g of the first surface treatment particle dispersion. The surface tension of this coating solution was 22 mN / m.

[0054] [Example 4] A titanium dioxide-containing coating solution was obtained in the same manner as in Example 1, except that 8.2 g of 3-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-503) was added to 80.0 g of the first surface treatment particle dispersion. The surface tension of this coating solution was 22 mN / m.

[0055] [Example 5] A titanium dioxide-containing coating solution was obtained in the same manner as in Example 1, except that 4.9 g of 3-acryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-5103) was added to 80.0 g of the first surface treatment particle dispersion. The surface tension of this coating solution was 15 mN / m.

[0056] [Example 6] A titanium dioxide-containing coating solution was obtained in the same manner as in Example 1, except that 4.9 g of 8-methacryloxyoctyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-5803) was added to 80.0 g of the first surface treatment particle dispersion. The surface tension of this coating solution was 20 mN / m.

[0057] [Example 7] A second surface-treated particle dispersion (inorganic oxide component concentration 20% by mass) was prepared in the same manner as in Example 1, except that IPA was used as the substituted solvent during the preparation of the second surface-treated particles. To this dispersion, 7.32 g was mixed with 0.15 g of 1,6-hexadiol diacrylate (Tomoe Kogyo Co., Ltd.: SR-238F) and 1.35 g of dipentaerythritol hexaacrylate (Kyoeisha Chemical Co., Ltd.: DPE-6A) as binder components, 0.09 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (IGMResins B.V.: OMNIRAD® TPO-H) as a photopolymerization initiator, and 73.82 g of IPA and 17.26 g of PGME as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 3% by mass. The surface tension of this coating solution was 22 mN / m.

[0058] [Example 8] To 11.71 g of the second surface-treated particle dispersion obtained in the same manner as in Example 7, 0.06 g of 1,6-hexadiol diacrylate (manufactured by Tomoe Engineering Co., Ltd.: SR-238F) and 0.54 g of dipentaerythritol hexaacrylate (manufactured by Kyoeisha Chemical Co., Ltd.: DPE-6A) were added as binder components, 0.04 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (manufactured by IGMResins B.V.: OMNIRAD® TPO-H) was added as a photopolymerization initiator, and 0.38 g of IPA and 17.27 g of PGME were added as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 3% by mass. The surface tension of this coating solution was 22 mN / m.

[0059] [Example 9] To 13.17 g of the second surface-treated particle dispersion obtained in the same manner as in Example 7, 0.03 g of 1,6-hexadiol diacrylate (manufactured by Tomoe Engineering Co., Ltd.: SR-238F) and 0.27 g of dipentaerythritol hexaacrylate (manufactured by Kyoeisha Chemical Co., Ltd.: DPE-6A) were added as binder components, 0.02 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (manufactured by IGMResins B.V.: OMNIRAD® TPO-H) was added as a photopolymerization initiator, and 69.23 g of IPA and 17.27 g of PGME were added as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 3% by mass. The surface tension of this coating solution was 22 mN / m.

[0060] [Example 10] To 13.17 g of the second surface-treated particle dispersion obtained in the same manner as in Example 4, 0.03 g of 1,6-hexadiol diacrylate (Tomoe Kogyo Co., Ltd.: SR-238F) and 0.27 g of dipentaerythritol hexaacrylate (Kyoeisha Chemical Co., Ltd.: DPE-6A) were added as binder components, 0.02 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (IGMResins B.V.: OMNIRAD® TPO-H) was added as a photopolymerization initiator, and 79.70 g of IPA and 6.80 g of PGME were added as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 3% by mass. The surface tension of this coating solution was 22 mN / m.

[0061] [Example 11] To 3.41 g of the second surface-treated particle dispersion obtained in the same manner as in Example 7, 0.03 g of 1,6-hexadiol diacrylate (manufactured by Tomoe Engineering Co., Ltd.: SR-238F) and 0.27 g of dipentaerythritol hexaacrylate (manufactured by Kyoeisha Chemical Co., Ltd.: DPE-6A) were added as binder components, 0.02 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (manufactured by IGMResins B.V.: OMNIRAD® TPO-H) was added as a photopolymerization initiator, and 78.63 g of IPA and 17.63 g of PGME were added as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 1% by mass. The surface tension of this coating solution was 22 mN / m.

[0062] [Example 12] To 17.07 g of the second surface-treated particle dispersion obtained in the same manner as in Example 7, 0.15 g of 1,6-hexadiol diacrylate (manufactured by Tomoe Engineering Co., Ltd.: SR-238F) and 1.35 g of dipentaerythritol hexaacrylate (manufactured by Kyoeisha Chemical Co., Ltd.: DPE-6A) were added as binder components, 0.09 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (manufactured by IGMResins B.V.: OMNIRAD® TPO-H) was added as a photopolymerization initiator, and 64.42 g of IPA and 16.90 g of PGME were added as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 5% by mass. The surface tension of this coating solution was 21 mN / m.

[0063] [Example 13] To 34.15 g of the second surface-treated particle dispersion obtained in the same manner as in Example 7, 0.30 g of 1,6-hexadiol diacrylate (manufactured by Tomoe Engineering Co., Ltd.: SR-238F) and 2.70 g of dipentaerythritol hexaacrylate (manufactured by Kyoeisha Chemical Co., Ltd.: DPE-6A) were added as binder components, 0.18 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (manufactured by IGMResins B.V.: OMNIRAD® TPO-H) was added as a photopolymerization initiator, and 46.67 g of IPA and 16.00 g of PGME were added as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 10% by mass. The surface tension of this coating solution was 16 mN / m.

[0064] [Example 14] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 1, except that the amount of organic solvent added during the preparation of the titanium dioxide-containing coating solution was 48.30 g of IPA and 40.50 g of PGME. The surface tension of this coating solution was 24 mN / m.

[0065] [Example 15] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 1, except that the organic solvents added during the preparation of the titanium dioxide-containing coating solution were 79.67 g of methanol and 9.12 g of PGME. The surface tension of this coating solution was 23 mN / m.

[0066] [Example 16] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 1, except that the organic solvents added during the preparation of the titanium dioxide-containing coating solution were 79.67 g of methyl ethyl ketone (MEK) and 9.12 g of PGME. The surface tension of this coating solution was 24 mN / m.

[0067] [Example 17] To 10.24 g of the second surface-treated particle dispersion obtained in the same manner as in Example 7, 0.09 g of 1,6-hexadiol diacrylate (manufactured by Tomoe Engineering Co., Ltd.: SR-238F) and 0.81 g of dipentaerythritol hexaacrylate (manufactured by Kyoeisha Chemical Co., Ltd.: DPE-6A) were added as binder components, 0.05 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (manufactured by IGMResins B.V.: OMNIRAD® TPO-H) was added as a photopolymerization initiator, and 1.35 g of IPA and 17.45 g of n-heptane were added as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 3% by mass. The surface tension of this coating solution was 19 mN / m.

[0068] [Example 18] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 17, except that the organic solvents added during the preparation of the titanium dioxide-containing coating solution were 71.35 g of IPA and 17.45 g of toluene. The surface tension of this coating solution was 22 mN / m.

[0069] [Example 19] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 17, except that the organic solvents added during the preparation of the titanium dioxide-containing coating solution were 1.35 g of IPA and 17.45 g of isopropyl glycol (I-PG). The surface tension of this coating solution was 24 mN / m.

[0070] [Example 20] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 17, except that the organic solvents added during the preparation of the titanium dioxide-containing coating solution were 1.35 g of IPA and 17.45 g of propylene glycol monomethyl ether acetate (PGMEA). The surface tension of this coating solution was 23 mN / m.

[0071] [Example 21] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 1, except that 6.54 g of tetramethoxysilane (manufactured by Tama Chemical Co., Ltd.) was added instead of tetraethoxysilane during the preparation of the first surface-treated particles. The surface tension of this coating solution was 22 mN / m.

[0072] [Example 22] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 1, except that tetrabutoxysilane (manufactured by Tokyo Chemical Industry Co., Ltd.) was added instead of tetraethoxysilane during the preparation of the first surface-treated particles. The surface tension of this coating solution was 22 mN / m.

[0073] [Example 23] To 10.24 g of the second surface-treated particle dispersion obtained in the same manner as in Example 1, 0.08 g of 1,6-hexadiol diacrylate (Tomoe Engineering Co., Ltd.: SR-238F) and 0.68 g of dipentaerythritol hexaacrylate (Kyoeisha Chemical Co., Ltd.: DPE-6A) were added as binder components, 0.05 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (IGMResins B.V.: OMNIRAD® TPO-H) was added as a photopolymerization initiator, 1.50 g of acrylic silicone copolymer (Kusumoto Chemical Co., Ltd.: Disparon NSH-8430HF, active ingredient concentration 10% by mass) was added as a leveling agent, and 79.80 g of IPA and 9.15 g of PGME were added as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 3% by mass. The surface tension of this coating solution was 22 mN / m.

[0074] [Comparative Example 1] A titanium dioxide-containing coating solution was obtained in the same manner as in Example 1, except that the amount of 3-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-503) used in the preparation of the second surface-treated particles was 0.2 g. The surface tension of this coating solution was 16 mN / m.

[0075] [Comparative Example 2] A titanium dioxide-containing coating solution was obtained in the same manner as in Example 1, except that the amount of 3-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-503) used in the preparation of the second surface-treated particles was 9.8 g. The surface tension of this coating solution was 22 mN / m.

[0076] [Comparative Example 3] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 1, except that the amount of tetraethoxysilane (manufactured by Tama Chemical Co., Ltd.) used in the preparation of the first surface-treated particles was 1.49 g. The surface tension of this coating solution was 21 mN / m.

[0077] [Comparative Example 4] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 1, except that the amount of tetraethoxysilane (manufactured by Tama Chemical Co., Ltd.) used in the preparation of the first surface-treated particles was 22.40 g. The surface tension of this coating solution was 21 mN / m.

[0078] [Comparative Example 5] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 1, except that 8.96 g of methyltrimethoxysilane (manufactured by Tama Chemical Co., Ltd.) was added instead of 3-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM-503) during the preparation of the first surface-treated particles. The surface tension of this coating solution was 21 mN / m.

[0079] [Comparative Example 6] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 1, except that the titanium dioxide-containing aqueous dispersion used in the preparation of the first surface treatment particles was an anatase-type titanium dioxide-containing particle-type aqueous dispersion prepared with reference to Example 1 of Japanese Patent Application Publication No. 2009-155496. The surface tension of this coating solution was 21 mN / m.

[0080] [Comparative Example 7] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 7, except that only 88.80 g of IPA was added as the organic solvent during the preparation of the titanium dioxide-containing coating solution. The surface tension of this coating solution was 22 mN / m.

[0081] [Comparative Example 8] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 1, except that only 8.80 g of PGME was added as the organic solvent during the preparation of the titanium dioxide-containing coating solution. The surface tension of this coating solution was 27 mN / m.

[0082] [Comparative Example 9] A titanium dioxide-containing coating solution was prepared in the same manner as in Example 1, except that the amount of organic solvent added during the preparation of the titanium dioxide-containing coating solution was 17.30 g of IPA and 1.50 g of PGME. The surface tension of this coating solution was 25 mN / m.

[0083] [Comparative Example 10] In preparing the titanium dioxide-containing coating solution, 4.39 g of the second surface-treated particle dispersion obtained in the same manner as in Example 7 was mixed with 0.21 g of 1,6-hexadiol diacrylate (manufactured by Tomoe Engineering Co., Ltd.: SR-238F) and 1.89 g of dipentaerythritol hexaacrylate (manufactured by Kyoeisha Chemical Co., Ltd.: DPE-6A) as binder components, 0.13 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (manufactured by IGMResins B.V.: OMNIRAD® TPO-H) as a photopolymerization initiator, and 76.12 g of IPA and 17.25 g of PGME as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 3% by mass. The surface tension of this coating solution was 22 mN / m.

[0084] [Comparative Example 11] To 114.88 g of the second surface-treated particle dispersion obtained in the same manner as in Example 7, 0.03 g of 1,6-hexadiol diacrylate (manufactured by Tomoe Engineering Co., Ltd.: SR-238F) and 0.27 g of dipentaerythritol hexaacrylate (manufactured by Kyoeisha Chemical Co., Ltd.: DPE-6A) were added as binder components, 0.02 g of diphenyl (2,4,6-trimethylbenzoyl)-phenylphosphine oxide (manufactured by IGMResins B.V.: OMNIRAD® TPO-H) was added as a photopolymerization initiator, and 1.95 g of IPA and 172.75 g of PGME were added as organic solvents to prepare a titanium dioxide-containing coating solution with a solid content of 3% by mass. The surface tension of this coating solution was 22 mN / m.

[0085] [Reference example 1] <Formation of substrate with anti-reflective coating> In Example 1, a titanium dioxide-containing film-coated substrate was coated with a low refractive index film-forming coating solution (ELCOM P-5062, manufactured by JGC Catalysts & Chemicals Co., Ltd.) using a bar coater method (#4). After drying at 80°C for 120 seconds, the substrate was cured by irradiation with 400 mJ / cm2 ultraviolet light under an N2 atmosphere to form a low refractive index film and obtain a substrate with an anti-reflective film. The thickness of the low refractive index film was approximately 100 nm.

[0086] "evaluation" The properties of the obtained anti-reflective coating were evaluated as follows. The results are shown in Table 3.

[0087] (exterior) The surface of the substrate with the anti-reflective coating was visually observed and evaluated, similar to the substrate with the titanium oxide-containing coating.

[0088] (reflectance) The reflectance was measured using a micro-spectroscopic film thickness meter (OPTM-A1, manufactured by Otsuka Electronics Co., Ltd.). The reflectance of the uncoated TAC substrate at a wavelength of 550 nm was 5.0%.

[0089] [Reference example 2] A substrate with an anti-reflective coating was obtained in the same manner as in Reference Example 1, except that the titanium dioxide-containing coating solution obtained in Example 2 was used.

[0090] [Reference example 3] A substrate with an anti-reflective coating was obtained in the same manner as in Reference Example 1, except that the titanium dioxide-containing coating solution obtained in Example 3 was used.

[0091] [Table 1]

[0092] [Table 2]

[0093] [Table 3]

Claims

1. First surface-treated particles in which a first organosilicon compound represented by formula (1) is bonded to the surface of titanium dioxide-containing particles, The organosilicon compound shown in formula (2), Binder components, A coating solution comprising a mixed solvent containing a low-boiling point organic solvent (S1) with a boiling point of less than 95°C and a high-boiling point organic solvent (S2) with a boiling point of 95°C or higher, The aforementioned titanium oxide crystal structure is rutile type, The first organosilicon compound is bonded to 10% by mass in terms of SiO2 in 100 parts by mass of the titanium oxide-containing particles. The molar ratio (second organosilicon compound / first organosilicon compound) of the first organosilicon compound to the second organosilicon compound or its hydrolysis compound is 0.3 to 2.

0. The solid content contains silicon derived from the first organosilicon compound and the second organosilicon compound in an amount of 5 to 20% by mass in terms of SiO2. The mass ratio (M) of the mixed solvent Ｓ１ / M Ｓ２ ) is 85 / 15 to 50 / 50, The mass ratio (M) of the inorganic oxide component (F) and the binder component (B) contained in the first surface-treated particles and the second organosilicon compound. Ｆ / M Ｂ A coating solution in which the ratio is 45 / 55 to 95 / 5. SiX ４ (1) R-(CH ２ ) ｎ SiX ３ (2) (X is at least one selected from an alkoxy group, a hydroxyl group, or a halogen. R is an acrylic group or a methacrylic group. n is an integer from 1 to 8.)

2. The coating solution according to claim 1, wherein the solid content concentration is 1 to 10%.

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