Composition for coating

【0001】

[Technical field to which the invention belongs]

The present invention relates to a coating composition for forming a high-refractive index coating film used for a functional film that selectively reflects or transmits a specific wavelength by multi-layer coating on plastic or glass. For details, select and reflect a specific wavelength by multi-layer coating on plastic or glass such as window glass and in-vehicle glass of buildings, films used by sticking them, lenses for eyeglasses, lenses for cameras, filters for displays, etc. , Or high suitable for film formation using wet film formation methods such as printing, spin coating, dip coating, spray coating, bar coating, roll coating and other coating methods to realize a transparent functional film. The present invention relates to a coating composition for forming a refractive index coating film.

【0002】

[Conventional technology]

In recent years, with the progress of thin film forming technology by the vapor phase growth method represented by the sputtering method, the ion plating method, and the chemical vapor deposition method, research on multilayer films such as optical multilayer interference films has been actively conducted. For example, a multilayer interference film having a function of an antireflection or antireflection film is used for a two-color filter, a cold mirror, a hot mirror, and the like. For example, a multilayer film using the interference effect of light obtained by alternately laminating thin films with a high refractive index and thin films with a low refractive index on a glass substrate in order to selectively reflect a desired wavelength range with an optical thickness of λ / 4. It has been known.

【0003】

However, for example, in the field of use where the infrared rays in the sunlight entering the inside of the building through the window glass are blocked to suppress the rise in the indoor temperature to save energy, the area to be shielded is often large. If it is attempted to be realized by the interference effect of light using a thin film forming technique, it will be very expensive and difficult to realize economically.

【0004】

In addition, for example, in plant plants, it has been clarified that the photoreceptor (phytochrome) of red / far-red photoreversible reaction is involved in the physiological reaction of germination, and it is cultivated by shielding a specific wavelength. It is expected to accelerate. However, in the fields of application such as plant plants, the area to be shielded is often large, and if it is to be realized by the interference effect of light using such a thin film forming technology, it will be very expensive and economical. It is difficult to realize.

【0005】

Further, for example, in a vinyl greenhouse, if the temperature inside the greenhouse becomes too high, the plant becomes ill, so it is expected that the blue to red wavelength region necessary for plant growth is transmitted and only the near infrared region is shielded. However, in the fields of application such as vinyl greenhouses, the area to be shielded is often large, and if it is to be realized by the interference effect of light using such a thin film forming technology, it will be very expensive and economical. It is difficult to realize.

【0006】

Further, for example, in a plasma display panel (PDP), which is an electronic image display device, since a light emitting body generates near infrared rays that cause peripheral devices to malfunction, shielding in the near infrared region is required. However, in the field of application where the near-infrared wavelength of the illuminant is shielded to suppress malfunction, the area to be shielded is often large, and if it is realized by the interference effect of light using such a thin film forming technology. , It becomes very expensive and the financial burden becomes large.

【0007】

From the above examples, it has been clarified that there is a demand for a film-forming body that has a function of wavelength selective reflection due to the interference effect of light, has a large utilization area, and is economically feasible. A number of technical proposals have been made regarding high-refractive index films that are useful for fulfilling this clarified request.

【0008】

Conventionally, a film made of an organic polymer resin containing fine particles having a refractive index of 1.7 or more has been proposed (see, for example, Patent Document 1). Patent Document 1 states that it is desirable that the amount of fine particles added is 65% by volume or less without air contamination, and a high-refractive index coating having a maximum refractive index of 2.31 has been proposed. Patent Document 1 does not mention the structure of the proposed film, but it is considered from the description that it proposes a state in which fine particles 102 are scattered in the organic polymer 101 as shown in FIG. 1, and FIG. 2 The structure in which the air 203 is mixed in the organic polymer 201 containing the fine particles 202 as shown in the above is not desirable. The present inventor tried the confirmation of Examples 3 and 5 described in Patent Document 1 showing a refractive index of 2 or more by trial and error, but could not reproduce it. It was considered that the reason why the results as described was not obtained was not that there was a problem in the experimental method of the present inventor, but that there was a defect in the invention in Patent Document 1. This is because, in Example 3 of Patent Document 1, a coating liquid prepared by blending 40% by volume of titanium oxide having a refractive index of 2.7 and 60% by volume of resin was prepared to obtain a refractive index of 2.10. Since the refractive index of the heat-curable acrylic resin is generally 1.47, the refractive index required for is equation 1 and can only be 1.96. Formula 1 2.7 × 0.4 + 1.47 × 0.6 = 1.96 Furthermore, although the compounding table states that the surfactant is 2% by weight based on titanium oxide, the specific gravity of the surfactant is generally 1, and that of rutyl-type titanium oxide. Since the specific gravity is 4.2, the volume conversion is about 8% by volume, and when combined with the result of Equation 1, the refractive index of the material obtained from the formulation of Example 3 is less than 1.90. Further, in Example 5, a film having a refractive index of 2.14 was obtained by blending zirconium oxide having a refractive index of 2.2 and an ultraviolet curable resin having a refractive index of 1.47. As shown in Equation 2, the material obtained in Example 5 can only be 1.98 at the maximum. Equation 2 2.2 × 0.65 + 1.47 × 0.35 = 1.

【0009】

Further, conventionally, a coating film containing titanium oxide having a particle size of 100 nm or less and a specific organic silane compound as main components has been proposed (see, for example, Patent Document 2). As described on page 9, the refractive index described in Patent Document 2 is expressed by Equation 3 with Wa as the weight% of the fine particles, Wd as the weight% of the binder, and f as the porosity. From Equation 3, the refractive index becomes maximum when the porosity f is 0, and a value close to about 2 can be set. However, in order to form a film having a refractive index of 2 using fine particles having a refractive index of 2.05, it is necessary that the film has no components other than fine particles such as voids and is completely densified with fine particles. The means to do so is not specified, and even in the examples, the maximum is only 1.73. Equation 3 (2.05Wa + 1.48Wd) × (1-f) /100+1.00f Although Wa and Wd shown in Equation 3 are weight%, in theory, volume% is generally correct. As described above, Patent Document 2 does not provide a film having a refractive index of 1.90 or more.

【0010】

Further, conventionally, it has been proposed to obtain a film having a high refractive index by dispersing and mixing fine particles of 100 nm or less in a resin binder containing cyclohexane as a main organic solvent within a range of 60% by weight or less (for example, patent). See Reference 3). There is no description of examples for obtaining a high refractive index film, and the expected refractive index and its film structure can only be predicted, but the proposal of Patent Document 3 is that the amount of fine particles with respect to the binder is small and the high refractive index is 1.9 or more. It is presumed that a refractive index film cannot be obtained.

【0011】

Further, conventionally, it has been proposed to form an organic-inorganic hybrid film with a composition containing titanium oxide fine particles, an organosilicon compound and a polyfunctional acrylic compound as main components (see, for example, Patent Document 4). The optimum compounding ratio of titanium oxide is 40 to 80% by weight, and a refractive index of 1.89 is obtained in the examples. Even when the present inventor conducted the test in accordance with Patent Document 4, only the film to the extent described in the examples could be obtained. It is presumed that the proposal of Patent Document 4 has a small amount of fine particles with respect to the binder as in Patent Document 3, and it is not possible to obtain a high refractive index film having a refractive index of 1.9 or more, which is the subject described later by the present inventor.

【0012】

As shown above, despite the fact that many detailed studies have been conducted and various patents have been applied for, it has an excellent function of wavelength selective reflection due to the interference effect of light, and has a large utilization area. , There is no economically feasible film-forming body yet.

【0013】

[Patent Document 1]

Japanese Patent Application Laid-Open No. 08-110401 [Patent Document 2]

Japanese Unexamined Patent Publication No. 63-247702 [Patent Document 3]

Japanese Unexamined Patent Publication No. 2000-26773 [Patent Document 4]

Japanese Unexamined Patent Publication No. 2001-164117 [0014]

[Problems to be Solved by the Invention]

Therefore, the present invention solves these problems and has a refractive index of 1.9 or more at the sodium D-line wavelength that can be used when forming an optical multilayer film having a function such as wavelength selective reflection on a substrate such as glass or plastic. An object of the present invention is to provide a coating composition for forming a film-forming body having a high refractive index film.

【0015】

[Means for solving problems]

As a result of diligent studies to achieve the above object, the present inventors have at least the following components (A), components (B), and components (C) in a coating composition for forming a high refractive index coating film. A coating for forming a high refractive index coating film, which contains the component (D) and the content of the component (A) is 350 to 1200 parts by weight with respect to 100 parts by weight of the component (C). The problem was solved by providing the composition for use. (A) Titanium oxide having a rutile-type crystal structure and fine particles having a particle diameter of 1 to 100 nm. (B) Heterocyclic nitrogen compound. (C) Binder precursor. (D) Organic solvent.

【0016】

When the coating composition of the present invention is formed by applying energy sufficient to form a film on the substrate and fix it, a transparent coating film having a high refractive index of 1.9 or more at the sodium D-line wavelength is obtained. .. In order to achieve a high refractive index of 1.9 or higher, a substance with a high refractive index should be densely packed while maintaining high dispersibility inside the structure of the film-forming body, and the proportion of the coating film volume should be increased as much as possible. It is a prerequisite.

【0017】

In order to make this condition a reality, as a result of careful examination from both theoretical and experimental viewpoints of the materials required for economical expression, the material having a high refractive index in the coating composition of the present invention. As a result, titanium oxide having a rutile structure having the highest refractive index among titanium oxides that are industrially economical and has a high refractive index is used, and the size of the rutile-type titanium oxide fine particles is fine particles having a particle diameter of 1 to 100 nm. (A) is used.

【0018】

Further, in the coating composition of the present invention, in order to obtain a coating film having a high refractive index of 1.9 or more, the content of the component (A) is 350 to 1200 weight by weight with respect to 100 parts by weight of the component (C) binder precursor. It is a department. When the component (A) is 1200 parts by weight or more, the fine particles are not densely filled in the drying step and the coating film curing step after coating, and the inside of the coating film becomes a coating film full of gaps, or the surface becomes an uneven coating film. There is a risk that the refractive index will decrease and white turbidity will occur due to cracking or cracking. If the weight is 350 parts by weight or less, the content of the binder is high, and a binder having a refractive index of about 1.5, which is usually used, cannot obtain a high refractive index coating film of 1.9 or more.

【0019】

Then, as a substance for improving the dispersion of the component (A), the component (B) heterocyclic nitrogen compound is used to modify the surface of the component (A). Generally, rutile-type titanium oxide having high crystallinity has poor dispersibility in an organic solvent, and the smaller the particle size, the larger the specific area, so that the dispersibility is further deteriorated. Therefore, as a result of a difficult study on improving the dispersibility of the component (A), the present inventor did not surface-treat the component (A) with a surfactant composed of a polymer of an organic compound to disperse the component (B). We succeeded in surface-treating with a heterocyclic nitrogen compound and dispersing it. As a result, the components (A) form a skeleton substantially closer to each other than when surface-treated with a dispersant such as a polymer surfactant, the volume ratio of the component (A) becomes higher, and the components (A) are formed by the skeleton. The voids become smaller, making it easier to obtain a high refractive index.

【0020】

Then, at the time of film formation, the function of replenishing the gap between the component (A), the base material, and the component (A) so as to be as small as possible to form a strong bond and suppress the decrease in the refractive index due to the gap. Use the component (C) binder precursor, which serves as a binder. The component (C) binder precursor in the present invention is not particularly limited, but the required characteristics vary depending on the substrate forming the film-forming body of the coating composition. For example, if it is a metal base material that is flexible, flexible and has high thermal expansion, an organic base material that has lower heat resistance than the metal base material, or an organic base material that is more transparent, a resin that can easily adapt to those characteristics. A system binder precursor is preferable. Among the resin-based binder precursors, a thermosetting resin that easily undergoes a cross-linking reaction due to external energy given during film formation to polymerize and solidify is preferable. Further, if weather resistance, heat resistance and the like are to be imparted, a resin-based binder precursor containing a silica element or / and a fluorine element in the molecular structure is preferable. Further, the inorganic oxide-based base material having rigidity and low thermal expansion such as glass is not limited to the resin-based binder precursor, and metal elements such as silica element, titanium element, zirconium element, and aluminum are used. A metal oxide-based binder precursor composed of a metal element selected from one or more different elements such as elements is preferable.

【0021】

Further, a component (D) organic solvent is used, in which the component (A), the component (B), and the component (C) are maintained at high dispersibility and can be formed into a film by a wet coating method. The component (D) organic solvent of the coating composition of the present invention is not particularly limited, but the above-mentioned component (A), component (B), and component (C) are maintained at high dispersibility and are wet-coated. It is provided so that a film can be formed by a method. The organic solvent is preferably alcohols and ketones, and isopropanol is particularly preferable. Further, a solvent containing isopropanol as a main component and a mixture of other alcohols, ketones, or / and esters is also preferably used.

【0022】

In a preferred embodiment of the present invention, the component (A) is a coating composition characterized by being titanium oxide dispersed at an average particle size of D50 at 50 nm or less. A high refractive index coating film cannot be realized simply by allowing the component (A) to exist inside the coating film. It is preferable that the component (A) is a coating composition in which the average particle size is D50 and the component (A) is highly dispersed to a level of 50 nm or less. Here, D50 is a particle size of 50% of the integrated value calculated by the number average confirmed by the laser diffraction / scattering method, the dynamic light scattering method, or the like. When the coating composition dispersed at this level is used, the component (A) is highly filled inside the coating film at the average particle size level or at a level close to the average particle size level, and the binder is buried in the gap. It becomes a state and realizes a transparent and high refractive index coating film.

【0023】

A preferred embodiment of the present invention is such that the component (B) is a coating composition characterized by being pyridine. As described above, the present inventor has succeeded in improving the dispersibility by surface-treating the component (A) with the above-mentioned component (B) heterocyclic nitrogen compound. As a result, the components (A) form a skeleton in close proximity to each other at less than 2 nm, the volume ratio of the component (A) becomes high, and the voids formed by the skeleton become small, making it easy to obtain a high refractive index. .. The heterocyclic nitrogen compound of the component (B) can be utilized not only in the coating composition but also in the slurry or sol prepared in the step before the preparation of the coating composition, and the dispersion of the component (A) can be utilized. Improves stability. Among the heterocyclic nitrogen compounds, pyridine, which is an inexpensive and easily available substance having excellent dispersion improving properties, is particularly preferable.

【0024】

Whether or not pyridine has been surface-treated on the component (A) can be confirmed by, for example, analysis by infrared spectroscopy. Infrared absorption spectrum measured by transmission or reflection method, 3020 to 3080 cm^-1And 1600 to 1450 cm^-1It can be known from the absorption spectrum derived from the pyridine ring of. (Reference: Color Material, Vol.57 (8), Page.447-455, 1984) [0025]

For example, a polymer of an organic compound (hereinafter referred to as an organic polymer) such as an amine-based surfactant represented by polyoxyethylene alkylamine (Amit 320 manufactured by Kao Co., Ltd.) is adsorbed on the surface of component (A). No matter how much the conventional method of forming a three-dimensional structure and stabilizing the dispersed state is used, the dispersion principle is a three-dimensional structure made of an organic polymer, and a film made of an organic polymer having a thickness of 6 nm or more on the surface of component (A). Is formed, and as a result, the refractive index is reduced and the target cannot be achieved. The thickness of the organic polymer can be obtained from the difference between the TEM and the particle size measurement of the dispersed slurry. (Reference: Color Material, Vol.62 (10), Page.587-593, 1989) [0026]

Regarding the preferred embodiment of the present invention, the following component (E) general formula Si-X¹₄Organosilicon compound represented by or / and a high polymer thereof (in the formula, X)¹Represents a hydrolyzable group or a hydroxyl group. ) Is contained in the coating composition. In order to achieve a high refractive index, as described above, the component (B) heterocyclic nitrogen compound is used as the dispersant of the component (A), and not only the coating composition but also the coating composition before preparation. It is preferable to disperse the slurry or sol adjusted in the step to a level of 50 nm or less with an average particle size of D50. In order to realize such a high level of dispersibility more easily and stably, the organosilicon compound or / or a high polymer of the component (E) that modifies and balances the surface of the component (A). Is preferably added.

【0027】

In a preferred embodiment of the present invention, the reactive functionality such that the component (C) exhibits a cross-linking reaction by applying one or more energies of radiation, electron beam, ultraviolet light, infrared ray, or heat. The coating composition is characterized by being an organosilicon compound having a group. The component (C) binder precursor is firmly bonded by replenishing the gaps between the component (A), the base material, and the components (A) at the time of film formation so as to be as small as possible, and is refracted by the voids. In addition to the function of suppressing the decrease in the rate, it is preferable that the compound has a reactive functional group that exhibits a cross-linking reaction in a general wet curing system using radiation, electron beam, ultraviolet rays, infrared rays, heat, or the like. .. The wet curing system is not limited because various film forming conditions can be selected depending on economic restrictions such as the substrate to be formed. However, in the case of a resin base material, it is better to avoid long-term exposure to ultraviolet rays having a temperature higher than the heat-resistant temperature or an output of 100 watts or more. Furthermore, since the component (A) becomes active when it receives light (ultraviolet) energy and has the property of decomposing organic substances by strong oxidative decomposition power (hereinafter referred to as photocatalytic activity), the decomposing power of the photocatalytic activity. It is preferable that the compound contains a bond having a bond energy that can withstand for a long period of time in the molecular structure. Further, it is preferable that the compound is economically easily available and can impart various characteristics. A preferred binder precursor having such properties is an organosilicon compound containing a SiO bond.

【0028】

In a preferred embodiment of the present invention, the component (C) is the general formula R.¹_a-Si-X²_(4-a)Organosilicon compound represented by (in the formula, R¹Represents a substituted or unsubstituted organic group having 3 or more carbon atoms, and X²Represents a hydrolyzable group or a hydroxyl group. a is an integer from 1 to 3. ) And / or a high polymer thereof. As described above, the component (C) binder precursor is an organosilicon compound having a Si-O bond in its molecular structure having a bond energy that can withstand the decomposing power of the photocatalytic activity of the component (A) for a long period of time. Is preferable, and an organosilicon compound having a reactive functional group that exhibits a cross-linking reaction in a general wet curing system is more preferable. The preferred structure is the general formula R.¹_a-Si-X²_(4-a)And / or a high polymer thereof, especially R¹Is preferably a polymerizable reactive functional group. Specific examples thereof include a vinyl group, an allyl group, a (meth) acrylic group, a 1-methylvinyl group, an epoxy group, a mercapto group, an amino group, a cyano group, and an isocyano group. The polymerized structural portion of these polymerizable reactive functional groups imparts the flexibility and flexibility required for the coating film.

【0029】

A preferred embodiment of the present invention is such that the coating composition further contains a photopolymerization initiator. Component (C) The crosslinkable reactive functional group contained in the binder precursor is a vinyl group, an allyl group, a (meth) acrylic group, or a 1-methylvinyl group having an unsaturated double bond that causes a radical polymerization reaction. In this case, it is preferable to add a photopolymerization initiator that generates radicals by absorbing light (ultraviolet rays) in order to cause a cross-linking reaction in a general wet curing system using light (ultraviolet rays) economically. ..

【0030】

A preferred embodiment of the present invention is such that the coating composition further contains a condensation catalyst. Component (C) When the crosslinkable reactive functional group contained in the binder precursor is a hydrolyzable group or hydroxyl group that causes a condensation reaction, it is economically inexpensive and can be used in a general wet curing system using infrared rays and heat. In order to cause the cross-linking reaction, it is preferable to add a condensation catalyst that rapidly accelerates the condensation reaction.

【0031】

A preferred embodiment of the present invention is a coating characterized in that the total concentration of the component (A), the component (B), the component (C), the photopolymerization initiator and the condensation catalyst is 30% by weight or less. Make it a composition for use. Considering the balance between the stability of the coating composition, the film forming method, the characteristics of the film forming body, and the like, the total concentration is preferably 30% by weight or less. When the total component concentration is 30% by weight or less, it can be set to meet various specifications (film thickness, film formation method, etc.), but when it exceeds 30% by weight, the dispersibility of the solid matter in the composition deteriorates, and the composition The stability of the object is significantly reduced and gelation is likely to occur. Further, when the concentration is high, the film forming property and the adhesion between the film-forming body of the composition and the base material are remarkably lowered, which is not preferable.

【0032】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in sequence.

【0033】

In order to realize a high refractive index of 1.9 or more at the sodium D-line wavelength of the formed coating film, the substance having a high refractive index used in the coating composition of the present invention has a rutile-type crystal structure. Limited to titanium oxide having. Generally, there are single materials or composite materials mainly composed of dielectrics such as metal oxides, nitrides, carbides, and fluorides as high refractive index materials, but typical materials with a refractive index of 2.0 or more are listed. Then, antimony sulfide (n = 3 ~ 4), iron oxide (n = 2.7 ~ 3.2), cadmium sulfide (n = 2.4 ~ 2.5), titanium oxide (n = 2.5 ~ 2.9), lead sulfide (n = 3.91) , Lead oxide (n = 2.5), silicon carbide (n = 2.6), calcium titanate (n = 2.34) and the like. However, an inexpensive and practical material having a high refractive index is titanium oxide having a rutile-type crystal structure having a refractive index of 2.7 or more.

【0034】

For antifouling purposes, use a mixture of one or two types of titanium oxide having anatase-type and brookite-type crystal structures that have stronger photocatalytic activity than rutile-type titanium oxide, which is the main component. You can also do it.

【0035】

The preferred form and size of rutile-type titanium oxide for the coating composition in the present invention are fine particles having a particle diameter of 1 to 100 nm. More preferably, the particles are 1 to 50 nm, and even more preferably 5 to 35 nm. Further, two or more kinds of components (A) having different average particle diameters D50 may be mixed. When such a component (A) is used, it is possible to contain 350 parts by weight or more of the component (A) with respect to 100 parts by weight of the component (C) binder precursor, and the coating film structure is dense. A coating film that is transparent and has a high refractive index of 1.9 or more can be realized. The particle shape is preferably spherical or close to it. When the shape has a large aspect ratio such as a needle shape, the density inside the coating film is lowered and a coating film having a high refractive index may not be obtained.

【0036】

Further, the coating composition of the present invention contains 350 to 1200 parts by weight of the component (A) with respect to 100 parts by weight of the component (C) binder precursor in order to obtain a coating film having a high refractive index of 1.9 or more. It is necessary to let it. Preferably, it is 400 to 1000 parts by weight. If we aim for a higher refractive index of 2.0 or higher, we need 500 to 700 parts by weight of component (A). When the component (A) is 1200 parts by weight or more, the fine particles are not densely filled in the drying step and the coating film curing step after coating, and the inside of the coating film becomes a coating film full of gaps, or the surface becomes an uneven coating film. There is a risk that the refractive index will decrease and white turbidity will occur due to cracking or cracking. If the weight is 350 parts by weight or less, the content of the binder is high, and a binder having a refractive index of about 1.5, which is usually used, cannot obtain a coating film having a high refractive index of 1.9 or more.

【0037】

In the coating composition of the present invention, it is preferable that the component (A) is a coating composition in which the average particle size is D50 and dispersed at 50 nm or less. More preferably, it is a coating composition having an average particle size of D50 and a high dispersion of 30 nm or less. When the coating composition dispersed at this level is used, the component (A) is highly filled inside the coating film at the average particle size D50 level of the coating composition or at a level close to it, and the gap is filled. The binder is buried, and a transparent and high refractive index coating film is realized. When a coating composition having an average particle size of D50 and 50 nm or more is used, when the appearance of the coating film is coated or when the film is formed, it becomes cloudy due to aggregation, cracks, etc., and the refractive index tends to decrease.

【0038】

Then, in the coating composition of the present invention, in order to disperse the component (A) to 50 nm or less at D50, the component (B) heterocyclic system having a function of modifying the surface of the component (A). Use a nitrogen compound. Further, the component (B) can be used not only in the coating composition but also in the slurry or sol prepared in the step before the coating composition preparation.

【0039】

Specific examples of the heterocyclic nitrogen compound used in the present invention include pyridine, 3-pyridinecarboxylic acid, 2-pyridinemethanol, pyridine N-oxide, 4-t-butylpyridine, 3,5-dimethylpyridine, pyrrole, and the like. It is preferably a chemical substance selected from pyrimidine, pyridazine, pyrrole, 2H-pyrrole, imidazole, pyrazole, isothiazole, and isooxazole. Particularly preferred is pyridine, which is the cheapest, easily available, and has excellent dispersion improving properties. The amount of these heterocyclic nitrogen compounds added should be in the range of about 0.5 to 40% by weight with respect to the weight of the component (A). Preferably, it is 1 to 30% by weight.

【0040】

Further, in the coating composition of the present invention, the following general formula Si-X is further used as a substance for improving the dispersion of the component (A).¹₄Organosilicon compound represented by or / and a high polymer thereof (in the formula, X)¹Represents a hydrolyzable group or a hydroxyl group. ) Is preferably contained. In the present invention, in order to further easily and stably realize dispersion stabilization in a coating composition, slurry, or sol with an average particle size of the component (A) of 50 nm or less at D50, further components ( It is preferable to add the organosilicon compound or / or a high polymer thereof of the component (E) that modifies and balances the surface of A). Functional group X of component (E) at the time of addition¹May be a functional group that remains hydrolyzable or a hydrolyzed hydroxyl group. Further, after the treatment, it is preferable that the hydrolyzable group reacts with the hydroxyl group of the component (A), but there is no problem in stability even in a state where a part of the hydrolyzable group remains. The amount of these organosilicon compounds added is preferably in the range of about 1 to 50 wt% with respect to the weight of the component (A). More preferably, it is 5 to 30 wt%.

【0041】

Specific examples of the component (E) include tetrachlorosilane, tetrabromsilane, tetramethoxysilane, tetraethoxysilane, tetrabutoxysilane, and dimethoxydiethoxysilane. Examples of high polymers include methyl silicate 51, ethyl silicate 40, HAS series such as HAS-1 and HAS-10 manufactured by Corcote Co., Ltd., and MCK silicate series manufactured by Mitsubishi Chemical Corporation.

【0042】

In the coating composition of the present invention, at the time of film formation, the gaps between the component (A), the base material, and the components (A) are replenished so as to be as small as possible so that the gaps are firmly bonded and the gaps are formed. The component (C) binder precursor, which serves as a binder that suppresses the decrease in the refractive index due to the above, is used. The component (C) binder precursor in the present invention is not particularly limited, but the required characteristics vary depending on the substrate forming the film-forming body of the coating composition. For example, if it is a metal base material that is flexible, flexible and has high thermal expansion, an organic base material that has lower heat resistance than the metal base material, or an organic base material that is more transparent, a resin that can easily adapt to those characteristics. A system binder precursor is preferable. Among the resin-based binder precursors, thermosetting resins that undergo a cross-linking reaction due to external energy given during film formation to be polymerized and easily solidified are preferable, and acrylic resins, epoxy resins, polyurethane resins, phenol resins, and ureas are preferable. Resin, unsaturated polyester resin, etc. can be used. Further, if weather resistance, heat resistance and the like are to be imparted, a resin-based binder precursor containing a silica element or / and a fluorine element in the molecular structure is preferable. For example, silicone resin, acrylic silicone resin, solvent-soluble fluororesin and the like can be used.

【0043】

Further, the inorganic oxide-based base material having rigidity and low thermal expansion such as glass is not limited to the resin-based binder, and metal elements such as silica element, titanium element, zirconium element, and aluminum element are used. A metal oxide-based binder precursor composed of a metal element selected from one or more different types is preferable. For example, monomers such as silane alkoxide, titanium alkoxide, zirconium alkoxide, and aluminum alkoxide, and high polymers having a high degree of polymerization can be used.

【0044】

In the coating composition of the present invention, in addition to the role of the above-mentioned component (C) as a binder for improving the physical and optical physical properties of the above-mentioned coating film, radiation, electron beam, ultraviolet rays, infrared rays, and the like. It is preferable that the organic silicon compound has a reactive functional group that exhibits a cross-linking reaction by applying energy of any one or more of heat. Such a reactive functional group is a functional group that causes a radical reaction, a functional group that causes an ionic reaction, or the like, and one or two reactive functional groups having different types of cross-linking reactions in the molecular structure of the compound. It may contain more than one kind of reactive functional group. The wet curing system is not particularly limited because various film forming conditions can be selected depending on economic restrictions such as the substrate to be formed. However, caution is required when using a resin base material that is sensitive to heat and ultraviolet rays. If exposed to a temperature higher than the heat-resistant temperature or ultraviolet rays with an output of 100 watts or more for a long time, there is a risk of causing a drastic composition change such as discoloration.

【0045】

Further, the binder precursor contains a Si-O bond, which is a compound that can withstand the decomposing power of titanium oxide when it has photocatalytic activity, and is a compound that is economically easily available and can impart various characteristics. It is preferably an organosilicon compound. The content of Si-O bonds contained in the molecular structure is preferably 10 wt% or more when all Si-O contained in the cured coating film is expressed as a value converted to SiO2. More preferably, it is 25 wt% or more. If it is 10 wt% or less, the characteristics of the silicone system disappear and the advantages such as weather resistance and high hardness cannot be obtained. Depending on the usage environment, the photocatalytic activity of component (A) cannot be withstood for a long time, and the coating film causes chalking and cloudiness.

【0046】

Further, in the coating composition of the present invention, the above-mentioned component (C) is a general formula R.¹_a-Si-X²_(4-a)Organosilicon compound represented by (in the formula, R¹Represents a substituted or unsubstituted organic group having 3 or more carbon atoms, and X²Represents a hydrolyzable group or a hydroxyl group. a is an integer from 1 to 3. ) And / or a high polymer thereof. As described above, the structure of the component (C) binder precursor is the above-mentioned general formula R.¹_a-Si-X²_(4-a)And / or a high polymer thereof, R¹Specific examples of the above include an alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, an isobutyl group, a hexyl group, a decyl group, an octadecyl group and a cyclohexyl group, an alkenyl group such as a vinyl group and an allyl group, and a phenyl group. Part or all of hydrogen atoms such as aryl group, trifluoropropyl group, perfluorobutylethyl group, perfluorooctylethyl group, 3-chloropropyl group, 2- (chloromethylphenyl) ethyl group, etc. were halogen-substituted. Epoxy functional group-containing groups such as groups, 3-glycidyloxypropyl groups, 2- (3,4-epoxycyclohexyl) ethyl groups, 5,6-epoxyhexyl groups, 9,10-epoxydecyl groups; 3-aminopropyl Group, N- (2-aminoethyl) aminopropyl group, 3- (N-phenylamino) propyl group, 3-dibutylaminopropyl group and other amino group-containing groups, 3-methacryloxypropyl group, 3-acryloxypropyl Sulfur-containing groups such as (meth) acrylic group-containing groups such as groups, 3-mercaptopropyl groups, 2- (4-mercaptomethylphenyl) ethyl groups, alkyl ethers such as polyoxyethyleneoxypropyl groups, etc., 3-hydroxycarbonyl Examples thereof include an anionic group such as a propyl group and a quaternary ammonium salt structure-containing group such as a 3-tributylammoniumpropyl group. Especially preferable R¹Is a polymerizable reactive functional group, and specific examples thereof include a vinyl group, an allyl group, a (meth) acrylic group, a 1-methylvinyl group, an epoxy group, a mercapto group, an amino group, a cyano group, and an isocyano group. .. The polymerized structural portion of these polymerizable reactive functional groups imparts the flexibility and flexibility required for the coating film. Also, X²Is a hydrolyzable functional group or hydroxyl group. Specific examples of the hydrolyzable functional group include an alkoxy group such as a methoxy group, an ethoxy group and a methoxyethoxy group, a halogen group such as a chloro group and a bromo group, an acyloxy group and the like. Particularly preferred are hydroxyl groups or methoxy groups. This R¹, X²The number of the coating film is preferably determined in consideration of the balance of various physical properties such as flexibility, flexibility, hardness and weather resistance of the coating film.

【0047】

Corresponding to the component (C) of the coating composition of the present invention, the general formula R¹_a-Si-X²_(4-a) Specific examples of the organic silicon compound represented by are, vinyltrialkoxysilane, vinyltrichlorosilane, vinyltri (β-methoxy-ethoxy) silane, allyltrialkoxysilane, acrylicoxypropyltrialkoxysilane, (meth) acrylicoxypropyl. There are trialkoxysilane, γ-glycidoxypropyltrialkoxysilane, β- (3,4-epoxycyclohexyl) -ethyltrialkoxysilane, mercaptopropyltrialkoxysilane, γ-aminopropyltrialkoxysilane and the like.

【0048】

In the coating composition of the present invention, vinyl polymerization is possible by irradiation with high energy rays such as ultraviolet rays and electron beams in order to form a film by bonding a network of siloxane bonds and a vinyl polymer chain (meth) acrylic. A functional group and a hydrolyzable group typified by an alkoxy group or a silanol group capable of a cross-linking reaction, a silanol group, or the like may be contained in the same molecule. The (meth) acrylic functional group contained in the organosilicon compound that can be used in the present invention is not particularly limited, and for example, 3- (meth) acryloxypropyl group, (meth) acryloximethyl group, 1,1 -(Meta) Acryloxiundecyl group and the like can be mentioned. In particular, specific examples of (meth) acryloxy-functional organosilicon compounds include 3- (meth) acryloxipropyltrimethoxysilane, 3- (meth) acryloxitriethoxysilane, and 3- (meth) acryloxipropylmethyldimethoxysilane. , 3- (Meta) acryloxypropylmethyldiethoxysilane and the like.

【0049】

The coating composition of the present invention may contain a polyfunctional (meth) acrylic compound containing no silicon atom in order to act as a cross-linking agent and improve adhesiveness. The compound is not particularly limited as long as it has two or more (meth) acrylic functional groups in one molecule. Specific examples thereof include ethylene glycol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and 1,9-nonanediol di (meth) acrylate. Neopentyl glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, 2 -Hydroxy-1,3 di (meth) acryloxypropane, 2,2-bis [4-((meth) acryloxyethoxy) phenyl] propane, 2,2-bis [4-((meth) acryloxypolyethoxy)) Bifunctional (meth) acrylates such as phenyl] propane, trifunctional (meth) acrylates such as trimethylpropantri (meth) acrylates, pentaerythritol tri (meth) acrylates, and tris [(meth) acryloxyethyl] isocyanurates. Examples thereof include tetrafunctional (meth) acrylates such as acrylates and pentaerythritol tetra (meth) acrylates. Further, any material such as divinylbenzene that polymerizes by irradiation with high energy rays and acts as a cross-linking agent can be applied. The polyfunctional (meth) acrylic compound containing no silicon atom is preferably 500 parts by weight or less, particularly preferably 200 parts by weight or less, based on 100 parts by weight of the organosilicon compound used in the present invention. If it is used in excess of 500 parts by weight, the characteristics of the silicone system disappear and the advantages such as weather resistance and high hardness cannot be obtained.

【0050】

Specific examples of the high polymer of the component (C) of the coating composition of the present invention include Japanese Patent No. 3222386, Japanese Patent Application Laid-Open No. 6-29382, Japanese Patent No. 3053353, Japanese Patent No. 2738235, Japanese Patent No. 2762206, and Japanese Patent No. It is preferable that the coating composition as shown in No. 2782405, Japanese Patent No. 2587340, Japanese Patent No. 2639286, Japanese Patent No. 2647285, etc. is mentioned. The content of Si-O bonds contained in the molecular structure of the high polymers listed above is 10 wt% or more when all Si-O contained in the cured coating film is expressed in terms of SiO2. Is preferable. More preferably, it is 25 wt% or more. If it is 10 wt% or less, the characteristics of the silicone system disappear and the advantages such as weather resistance and high hardness cannot be obtained. Depending on the usage environment, the photocatalytic activity of titanium oxide cannot be withstood for a long time, and the coating film causes chalking and cloudiness. Specific examples on the market include (trade name), X-12-2400 and X-12-2450 manufactured by Shin-Etsu Chemical Silicone Co., Ltd., and the components of the coating composition ( It is a preferred binder precursor for C).

【0051】

Regarding the coating composition of the present invention, it is preferable that the coating composition further contains a photopolymerization initiator. Component (C) The crosslinkable reactive functional group contained in the binder precursor is a vinyl group, an allyl group, a (meth) acrylic group, or a 1-methylvinyl group having an unsaturated double bond that causes a radical polymerization reaction. In this case, in order to cause a cross-linking reaction in a general wet curing system that economically uses light (ultraviolet), a photopolymerization initiator that generates radicals by absorbing high energy such as light (ultraviolet) is added. can do. The amount of the photopolymerization initiator added is preferably 0.01 to 10 parts by weight, particularly in the range of 0.5 to 1 part by weight, based on 100 parts by weight of the component (C) binder precursor. Is preferable. If the amount used is less than 0.01 parts by weight, the curing rate becomes slow and good productivity may not be obtained, and if it exceeds 10 parts by weight, the cured film may soften.

【0052】

The photopolymerization initiator used in the present invention is not particularly limited, and can be appropriately selected from known ones. Specifically, benzoin derivatives such as benzoin, benzoin ethyl ether, benzoin propyl ether, benzoin isopropyl ether; 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2 -2-Hydroxy-2-methyl-1-phenylpropan-1-derivatives such as hydroxy-2-methylpropan-1-one, acetophenone derivatives such as dimethoxyacetophenone and diethoxyacetophenone, benzophenones, 4,4'-bis ( Dimethylamino) benzyl dimethyl ketal, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and the like.

【0053】

Regarding the coating composition of the present invention, it is preferable that the coating composition further contains a condensation catalyst. Component (C) When the crosslinkable reactive functional group contained in the binder precursor is a hydrolyzable group or a hydroxyl group that causes a condensation reaction, it is more economically crosslinked by a general wet curing system using infrared rays and heat. In order to cause the reaction, a condensation catalyst that rapidly accelerates the condensation reaction can be added.

【0054】

This condensation catalyst can be appropriately selected and used from known catalysts. Specific examples of the condensation catalyst used in the present invention include lithium hydroxide, sodium hydroxide, potassium hydroxide, sodium methylate, sodium acetate, sodium formate, n-hexylamine, tributylamine, diazabicycloundecene and the like. Basic compounds; tetraisopropyl titanate, tetrabutyl titanate, aluminum triisobutoxide, aluminum triisopropoxide, aluminum acetylacetonate, aluminum perchlorate, aluminum chloride, cobalt octylate, cobalt acetylacetonate, zinc octylate, zinc Metal-containing compounds such as acetylacetonate, iron acetylacetonate, tin acetylacetonate, dibutyltin octylate and dibutyltin laurate; acidic compounds such as p-toluenesulfonic acid and trichloroacetic acid can be mentioned.

【0055】

The amount of the condensation catalyst used is preferably 0.01 to 10 parts by weight, particularly preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the component (C) binder precursor. If the amount used is less than 0.01 parts by weight, the curing rate may slow down and good productivity may not be obtained, and if it exceeds 10 parts by weight, the storage stability of the hydrolyzate of the organosilicon compound may decrease. is there.

【0056】

Further, in the coating composition of the present invention, in order to improve the storage stability of the component (C) binder precursor, the following general formula R³ COCH₂ COR⁴(In the formula, R³Has 1 carbon number such as ethyl group, n-propyl group, i-propyl group, n-butyl group, sec-butyl group, t-butyl group, n-pentyl group, n-hexyl group, cyclohexyl group, phenyl group, etc. Shows a monovalent hydrocarbon group of ~ 6, R⁴Is R³ In addition to monovalent hydrocarbon groups with 1 to 6 carbon atoms similar to the above, methoxy group, ethoxy group, n-propoxy group, i-propoxy group, n-butoxy group, sec-butoxy group, t-butoxy group, lauryl A group consisting of β-diketones and β-ketoesters represented by an alkoxyl group having 1 to 16 carbon atoms such as an oxy group and a stearyloxy group, a carboxylic acid compound, a dihydroxy compound, an amine compound, and an oxyaldehyde compound. At least one selected from the above can be added. Such components are particularly preferably used in combination when an organometallic compound or the like is used as the condensation catalyst.

【0057】

The general formula R³ COCH₂ COR⁴The component represented by is one that acts as a stability improver for the composition. That is, the general formula R³ COCH₂ COR⁴The component represented by is coordinated with a metal atom of the above-mentioned condensation catalyst organometallic compound or the like to appropriately control the action of the organometallic compound or the like to promote the condensation reaction of the silanol group of the component (C) binder precursor. As a result, it is presumed that it acts to further improve the storage stability of the obtained composition. The amount of the component used is usually 2 mol or more, preferably 3 to 20 mol, with respect to 1 mol of the organometallic compound in the above-mentioned organometallic compound or the like. In this case, the general formula R³ COCH₂ COR⁴If the amount of the component represented by is less than 2 mol, the effect of improving the storage stability of the obtained composition tends to be insufficient.

【0058】

The general formula R³ COCH₂ COR⁴Specific examples of the components represented by are acetylacetone, methyl acetoacetate, ethyl acetoacetate, -n-propyl acetoacetate, -i-propyl acetoacetate, -n-butyl acetoacetate, -sec-butyl acetoacetate, and aceto. Acetic acid-t-butyl, hexane-2,4-dione, heptan-2,4-dione, heptan-3,5-dione, octane-2,4-dione, nonane-2,4-dione, 5-methylhexane -2,4-dione, malonic acid, oxalic acid, phthalic acid, glycolic acid, salicylic acid, aminoacetic acid, iminoacetic acid, ethylenediaminetetraacetic acid, glycol, catechol, ethylenediamine, 2,2-bipyridine, 1,10-phenanthroline, diethylenetriamine , 2-Ethanolamine, dimethylglioxime, dithizone, methionine, salicylaldehyde and the like. Of these, acetylacetone and ethyl acetoacetate are preferable. The general formula R³ COCH₂ COR⁴The components represented by can be used alone or in combination of two or more.

【0059】

In the component (C) binder precursor of the coating composition of the present invention, in the case of an organosilicon compound containing a silanol group, the pH should be adjusted to 3 to 6 in order to further improve the stability of the silanol group. Is preferable. As the buffer solution for adjusting the pH, a combination of an acid and a basic compound may be used. For example, there are combinations of acetic acid and sodium acetate, disodium hydrogen phosphate and citric acid, and the like. Further, also in the coating composition of the present invention, a method for adjusting pH is appropriately used.

【0060】

The component (D) organic solvent of the coating composition of the present invention can form a film of the above components (A), component (B), and component (C) while maintaining high dispersibility by a wet coating method. Make it something that has been given. With these coating compositions, a film having a high refractive index at the sodium D-line wavelength can be obtained. Specific examples of the component (D) organic solvent include ketones such as methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), and acetyl acetone, methanol, ethanol, isopropyl alcohol, n-butanol, isobutanol, t-butanol, and t-. Amino alcohol Butyl cellosolve, 3-methyl-3-methoxybutanol, alcohols such as diacetone alcohol (DAA), ethers such as propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, diisopropyl ether, esters such as ethyl acetate and isobutyl acetate. Kind and so on. Preferred organic solvents are alcohols and ketones, with isopropanol being particularly preferred. Further, a solvent containing isopropanol as a main component and a mixture of other alcohols, ketones, or / and esters is also preferably used.

【0061】

Additives may be separately added and dispersed in the composition used in the present invention in order to color the obtained coating film and improve the film-forming property. In particular, an organic ultraviolet absorber, an ultraviolet stabilizer, a light stabilizer and the like may be added for the purpose of improving the weather resistance and durable adhesion of the composition of the present invention. Examples of the organic ultraviolet absorber include salicylic acid-based, benzophenone-based, benzotriazole-based, cyanoacrylate-based, and triazine-based. Moreover, as an ultraviolet stabilizer, a piperidine type and the like can be mentioned. Moreover, as a light stabilizer, a hindered amine type and the like can be mentioned.

【0062】

In addition, a leveling agent can be blended in order to further improve the coating property of the coating composition of the present invention. Among such leveling agents, fluorine-based leveling agents (trade names; the same shall apply hereinafter) include, for example, BM1000 and BM1100 from BM-CHEMIE; Fuka 772 and Fuka 777 from Fuka Chemicals; Floren series manufactured by Sumitomo Corporation; FC series of Sumitomo 3M Co., Ltd.; Fluoronal TF series of Toho Chemical Industry Co., Ltd., etc. Examples of silicone-based leveling agents include BYK series of Big Chemie Co., Ltd .; Schmegman. (Sshmegmann) Sshmego series; Fuka Chemicals Fuka 30, Fuka 31, Fuka 34, Fuka 35, Fuka 36, Fuka 39, Fuka 83, Fuka 86, Fuka 88, etc., ether type or ester Examples of the leveling agent of the system include Surfinol of Nissin Chemical Industry Co., Ltd .; Emargen and Homogenol of Kao Corporation. By blending such a leveling agent, the finished appearance of the coating film is improved, and the thin film can be uniformly applied. The amount of the leveling agent used is preferably 0.01 to 5% by weight, more preferably 0.02 to 3% by weight, based on the total composition.

【0063】

In the coating composition of the present invention, the total concentration of the component (A), the component (B), the component (C), the component (E), the photopolymerization initiator, and the condensation catalyst shall be 30% by weight or less. Is preferable. The total concentration is preferably in the above range in consideration of the balance between the stability of the coating composition, the film forming method, the characteristics of the film forming body, and the like. Further, the general formula R is further added to the components (A) to (E), the photopolymerization initiator, and the condensation catalyst.³ COCH₂ COR⁴It is preferable that the total concentration of the components containing the components represented by is 30% by weight or less. When the total component concentration is 30% by weight or less, it can be set to meet various specifications (film thickness, film formation method, etc.), but when it exceeds 30% by weight, the dispersibility of the solid matter in the composition deteriorates, and the composition The stability of the object is significantly reduced and gelation is likely to occur. Further, when the concentration is high, the film forming property and the adhesion between the film-forming body of the composition and the base material are remarkably lowered, which is not preferable.

【0064】

Further, when preparing the coating composition of the present invention, the condensation catalyst and the general formula R are used.³ COCH₂ COR⁴When the components represented by are not used, the mixing method of each component is not particularly limited, but the condensation catalyst and the general formula R are not particularly limited.³ COCH₂ COR⁴When the components represented by are used, preferably, after obtaining a mixture of the components (A) to (E), the photopolymerization initiator, and the condensation catalyst, the general formula R is applied thereto.³ COCH₂ COR⁴The method of adding the component represented by is adopted.

【0065】

As an example of the step of adjusting the coating composition of the present invention, the components (A) to (E) of the coating composition of the present invention and the photopolymerization initiator are mixed at once, and the working environment temperature. Or, a method of performing bead milling for 1 to several tens of hours or several days in the range of 0 to 50 ° C, preferably 5 to 30 ° C, and more preferably 5 to 15 ° C at the temperature of the coating composition. It is preferably used. Further, a slurry or sol in which the component (A), the component (B), the component (D), or / and the component (E) are dispersed in the same process as described above with the average particle size of the component (A) being D50 and 50 nm or less. A method in which a required amount of the component (C), a photopolymerization initiator, or / and a condensation catalyst is added to the obtained slurry or sol and a bead mill treatment or the like is also preferably used. As a method of blending a leveling agent for further improving the coating property of the coating composition of the present invention, it may be blended at the time of preparing the composition, or at the stage of forming the coating film. It may be blended in both the preparation of the composition and the formation of the coating film.

【0066】

Suitable substrates for using the coating compositions of the present invention include metals such as iron, aluminum and stainless steel; inorganics such as cement, concrete, ALC, flexible boards, mortar, slate, gypsum, ceramics and bricks. Ceramic materials; plastic molded products such as phenol resin, epoxy resin, polyester, polycarbonate, polyethylene, polypropylene, ABS resin (acrylonitrile-butadiene-styrene resin); polyethylene, polypropylene, polyvinyl alcohol, polycarbonate, polyethylene terephthalate, polyurethane, polyimide, etc. Plastic film, wood, paper, glass, etc. can be mentioned. These base materials can be surface-treated in advance for the purpose of adjusting the base, improving the adhesion, sealing, smoothing, and patterning the porous base material. Examples of the surface treatment for the metal-based base material include polishing, degreasing, plating treatment, chromate treatment, flame treatment, and coupling treatment, and examples of the surface treatment for the plastic-based base material include blast treatment and the like. Chemical treatment, degreasing, flame treatment, oxidation treatment, steam treatment, corona discharge treatment, ultraviolet irradiation treatment, plasma treatment, ion treatment and the like can be mentioned. Examples of surface treatments for inorganic ceramic base materials include polishing and eye treatment. Examples of the surface treatment for the wood base material include polishing, filling, and insect repellent treatment, and examples of the surface treatment for the paper base material include sealing and sealing. Insect repellent treatment and the like can be mentioned, and further, as the surface treatment for the deteriorated coating film, for example, keren and the like can be mentioned.

【0067】

If necessary, a primer may be used in the coating composition of the present invention. For example, in the case of a metal-based base material, if rust prevention is required, a primer is used in addition to the coating composition of the present invention, and in the case of an inorganic ceramic-based base material, the characteristics of the base material (surface roughness, impregnation property, Since the hiding power of the coating film differs depending on (alkaline, etc.), a primer may be used. In the case of repainting the deteriorated coating film, a primer is used when the deterioration of the old coating film is remarkable. In the case of other base materials such as plastic, wood, paper, glass and the like, a primer may or may not be used depending on the application. The type of the primer is not particularly limited as long as it has an effect of improving the adhesion between the base material and the composition, and is selected according to the type of the base material and the purpose of use. The primer can be used alone or in combination of two or more, and may be an enamel containing a coloring component such as a pigment or a clear primer not containing the coloring component.

【0068】

Examples of the type of primer include alkyd resin, aminoalkyd resin, epoxy resin, polyester, acrylic resin, urethane resin, fluororesin, acrylic silicon resin, acrylic resin emulsion, epoxy resin emulsion, polyurethane emulsion, polyester emulsion and the like. Can be done. Further, as these primers, when adhesion between the base material and the coating film is required under severe conditions, primers to which various functional groups are added can also be used. Examples of such a functional group include a hydroxyl group, a carboxyl group, a carbonyl group, an amide group, an amine group, a glycidyl group, an alkoxysilyl group, an ether bond, and an ester bond. Further, the primer may contain an ultraviolet absorber, an ultraviolet stabilizer, or the like.

【0069】

As a method of applying the coating composition of the present invention to a substrate, a brush, a roll coater, a flow coater, a centrifugal coater, an ultrasonic coater, a (micro) gravure coater, or the like can be used, or a dip coat, a sink coat, a spray, or a screen can be used. Examples include process, electrodeposition, and vapor deposition. In particular, preferred wet coating methods for the coating composition of the present invention include, for example, a pre-weighing reverse roll coater method, a forward rotation roll method, a gravure coat method, a kiss coater method, a roll dip coater method, a slot olifill coater method, and the like. , Post-weighing blade method, rod method, spin coating method, screen coating method, etc. The coating method described above can also be used as a primer, and the composition of the present invention can be applied by applying a primer to a substrate in advance.

【0070】

As an example of the step of forming the coating film of the coating composition used in the present invention, the dry film thickness is about 10 to 1,000 nm in a single coating, and then dried at room temperature, or A coating film can be formed by heating and drying at a temperature of about 30 to 200 ° C. for about 1 to 60 minutes and irradiating a required amount of electron beam or ultraviolet rays. Further, the composition can be dried with infrared rays and irradiated with an electron beam or ultraviolet rays in a required amount to form a coating film. It is also possible to form a coating film by applying a second coating on the formed coating film. Further, if it is necessary to form a laminated coating film or a multilayer coating film in the coating film specifications, the coating film obtained from the coating composition of the present invention can be laminated three times or more. Further, for example, a coating composition of the present invention and a composition for forming a coating film having a refractive index lower than that of the coating composition, or a coating composition are alternately formed and laminated in multiple layers to form a near-infrared heat ray blocking film. It is also possible to obtain a wavelength-selective functional film such as that used for an ultraviolet blocking film or the like.

【0071】

[Example]

Next, an embodiment of the present invention will be specifically shown. However, the present invention is not limited thereto. Further, in the present invention, the following measuring means are used. (Average particle size) In the present invention, the average particle size D50 of the coating composition, the slurry, or the fine particles dispersed in the sol is a number average value measured by a dynamic light scattering method. For the measurement, for example, "Microtrap UPA150" manufactured by Nikkiso Co., Ltd. can be used. Further, the particles refer to particles in a colloidal state, and may be primary particles or secondary particles. The particle size described for the raw material fine particles is a catalog value of the manufacturer. (Average diameter of gap) The area of each pore is calculated from the observation photograph of the pore whose cross section is confirmed by means such as SEM and TEM, and the diameter when calculated as a circle is taken as the diameter of the pore, and the diameter of the pore in the observation field is The most frequent value was taken as the average diameter of the pores. (Refractive index) In the present invention, the refractive index of the base material is the multi-wavelength Abbe refractometer Atago DR-M2, and the low refractive index layer and the high refractive index layer are the spectroscopic ellipsometer JOVIN YVON UVISEL. It is a value with respect to the sodium D line wavelength (wavelength 589 nm) measured by the thin film refractive index measuring means using. (Optical Thickness) In the present invention, it is a value obtained by multiplying the film thickness and the refractive index measured by a thin film thickness measuring means using a UVISEL manufactured by JOVIN YVON, a spectroscopic ellipsometer. (Reflectance) In the present invention, it is a value with respect to an incident angle of 5 ° measured by a spectrophotometer U-4000 manufactured by Hitachi. (Transmittance) In the present invention, it is a value with respect to an incident angle of 0 ° measured by a spectrophotometer U-4000 manufactured by Hitachi. (Volume ratio of air layer) The volume ratio of the air layer was calculated by comparing the film thickness observed by SEM with the film thickness estimated from fluorescent X-rays.

【0072】

(Example 1) As shown in Table 1, the raw materials were mixed and dispersed in a ball mill for 4 hours, and after confirming that the dispersed particle size reached 20 nm at D50, an ultraviolet curing binder (X-12-2400 manufactured by Shin-Etsu Chemical Co., Ltd.) , Active ingredient 30% by weight) 1.5 parts by weight, catalyst (DX-2400 manufactured by Shin-Etsu Chemical Co., Ltd.) 0.15 parts by weight, dispersed in a ball mill for 1 hour, and confirmed that the dispersed particle size reached 16 nm at D50. This was designated as the high refractive index coating liquid A. This was applied to a PET film (thickness 50 μm) with a bar coater No. 08 so that the dry film thickness was 100 nm, dried at 100 ° C., irradiated with ultraviolet rays, cured, and the refractive index was measured. The results are shown in Table 2, and the results of electron microscopic observation of the cross section are shown in Fig. 3. A film-forming body having a refractive index of 2.17 was obtained, in which fine particles were 40% by volume or more, binder was 10% by volume or more, and air was 40% by volume or less, and excellent transparency (haze 1.4) and adhesion were obtained.

【0073】

[table 1]<img file="JP2004123766A_D0001.tif" /> 【0074】

[Table 2]<img file="JP2004123766A_D0002.tif" /> 【0075】

(Examples 2 to 8) Based on Tables 2 and 3, the raw materials were mixed, dispersed in a ball mill for 4 hours, and after confirming that the dispersed particle size reached 50 nm or less at D50, an ultraviolet curable binder (Shin-Etsu Chemical). Industrial X-12-2400) 1.5 parts by weight and catalyst (Shin-Etsu Chemical DX-2400) 0.15 parts by weight were mixed and dispersed in a ball mill for 1 hour, and the dispersed particle size reached 50 nm or less at D50. A coating solution was obtained. These were applied to a PET film (thickness 50 μm) with a bar coater No. 08 so that the dry film thickness was 100 nm, dried at 100 ° C., irradiated with ultraviolet rays, cured, and the refractive index was measured. The results are shown in Table 2. In each case, fine particles are 40% by volume or more, binder is 10% by volume or more, air is 40% by volume or less, and a film-forming body having excellent transparency (haze 2 or less) and adhesion and a refractive index of 1.90 or more can be obtained. It was.

【0076】

[Table 3]<img file="JP2004123766A_D0003.tif" /> 【0077】

(Example 9) As shown in Table 4, the raw materials were mixed, dispersed in a ball mill for 4 hours, and after confirming that the dispersed particle size reached 20 nm at D50, an ultraviolet curable binder (Shin-Etsu Chemical Co., Ltd. X-12- 2400) 1.8 parts by weight, catalyst (DX-2400 manufactured by Shin-Etsu Chemical Co., Ltd.) 0.09 parts by weight were mixed and dispersed in a ball mill for 1 hour, and it was confirmed that the dispersed particle size reached 20 nm or less at D50, and this was highly refracted. The rate coating liquid B was used. This was applied to a PET film (thickness 50 μm) with a bar coater No. 08 so that the dry film thickness was 100 nm, dried at 100 ° C., irradiated with ultraviolet rays, cured, and the refractive index was measured. The results are shown in Fig. 3. A film-forming body having a refractive index of 2.02 was obtained, in which fine particles were 40% by volume or more, binder was 10% by volume or more, and air was 40% by volume or less, and excellent transparency (haze 2 or less) and adhesion were obtained.

【0078】

[Table 4]<img file="JP2004123766A_D0004.tif" /> 【0079】

(Example 10) As shown in Table 5, the raw materials were mixed, dispersed in a ball mill for 4 hours, and after confirming that the dispersed particle size reached 20 nm at D50, an ultraviolet curable binder (Shin-Etsu Chemical Co., Ltd. X-12- 2400) 1.8 parts by weight, catalyst (DX-2400 manufactured by Shin-Etsu Chemical Co., Ltd.) 0.09 parts by weight were mixed and dispersed in a ball mill for 1 hour, and it was confirmed that the dispersed particle size reached 20 nm or less at D50, and this was highly refracted. The rate coating liquid C was used. This was applied to a PET film (thickness 50 μm) with a bar coater No. 08 so that the dry film thickness was 100 nm, dried at 100 ° C., irradiated with ultraviolet rays, cured, and the refractive index was measured. The results are shown in Fig. 3. The rutile-type titanium oxide fine particles 150W used had a substantially rectangular parallelepiped shape, but the fine particles were 40% by volume or more, the binder was 10% by volume or more, the air was 40% by volume or less, and the transparency (haze 2 or less) was achieved. A film-forming body having an excellent adhesion and a refractive index of 1.90 was obtained.

【0080】

[Table 5]<img file="JP2004123766A_D0005.tif" /> 【0081】

(Comparative Example 1) As shown in Table 6, the raw materials were mixed and dispersed in a ball mill for 4 hours. After confirming that the dispersed particle size reached 150 nm at D50, 1.8 parts by weight of the ultraviolet curable binder (X-12-2400 manufactured by Shin-Etsu Chemical Co., Ltd.) and 0.09 parts by weight of the catalyst (DX-2400 manufactured by Shin-Etsu Chemical Co., Ltd.) were mixed and ball milled. It was confirmed that the dispersed particle size reached 150 nm at D50, and this was used as the coating liquid D. This was applied to a PET film (thickness 50 μm) with a bar coater No. 08 so that the dry film thickness was 100 nm, dried at 100 ° C., irradiated with ultraviolet rays, cured, and the refractive index was measured. The results are shown in Fig. 3. A film-forming body having a refractive index of 1.70, which contained 40% by volume or less of fine particles and 40% by volume or more of air, lacked transparency (haze 11), and had poor adhesion, was obtained.

【0082】

[Table 6]<img file="JP2004123766A_D0006.tif" /> 【0083】

(Comparative Example 2) As shown in Table 7, the raw materials were mixed, dispersed in a ball mill for 4 hours, and after confirming that the dispersed particle size reached 100 nm at D50, an ultraviolet curable binder (Shin-Etsu Chemical Co., Ltd. X-12- 2400) 1.8 parts by weight and 0.09 parts of catalyst (DX-2400 manufactured by Shin-Etsu Chemical Co., Ltd.) were mixed and dispersed in a ball mill for 1 hour. And said. This was applied to a PET film (thickness 50 μm) with a bar coater No. 08 so that the dry film thickness was 100 nm, dried at 100 ° C., irradiated with ultraviolet rays, cured, and the refractive index was measured. The results are shown in Fig. 3. A film-forming body having a binder content of 10% by volume or less and air content of 40% by volume or more, lacking transparency (haze 8), and inferior adhesion was obtained with a refractive index of 1.73.

【0084】

[Table 7]<img file="JP2004123766A_D0007.tif" /> 【0085】

(Comparative Example 3) As shown in Table 8, the raw materials were mixed and dispersed in a ball mill for 4 hours. After confirming that the dispersed particle size reached 16 nm at D50, this was used as the coating liquid F. This was applied to a PET film (thickness 50 μm) with a bar coater No. 08 so that the dry film thickness was 100 nm, dried at 100 ° C., irradiated with ultraviolet rays, cured, and the refractive index was measured. The results are shown in Fig. 3. A film-forming body having a refractive index of 1.71 was obtained, in which the amount of air was 40% by volume or more and the transparency was excellent (haze 1.7), but the adhesion was inferior.

【0086】

[Table 8]<img file="JP2004123766A_D0008.tif" /> 【0087】

(Examples 11 to 14) Raw materials were mixed based on Tables 9 and 10 and dispersed in a ball mill for 4 hours. After confirming that the dispersed particle size reached 50 nm or less at D50, an ultraviolet curable binder (Shin-Etsu Chemical Co., Ltd.) X-12-2400 manufactured by X-12-2400) 1 to 10 parts by weight and catalyst (DX-2400 manufactured by Shin-Etsu Chemical Co., Ltd.) 0.1 to 1 part by weight were mixed and dispersed in a ball mill for 1 hour, and the dispersed particle size reached 20 nm or less at D50. A high refractive index coating liquid was obtained. This was applied to a PET film (thickness 50 μm) with a bar coater No. 08 so that the dry film thickness was 100 nm, dried at 100 ° C., irradiated with ultraviolet rays, cured, and the refractive index was measured. The results are shown in Fig. 5. In each case, fine particles are 40% by volume or more, binder is 10% by volume or more, air is 40% by volume or less, and a film-forming body having excellent transparency (haze 2 or less) and adhesion and a refractive index of 1.90 or more can be obtained. It was.

【0088】

[Table 9]<img file="JP2004123766A_D0009.tif" /> 【0089】

[Table 10]<img file="JP2004123766A_D0010.tif" /> 【0090】

(Comparative Example 4) As shown in Table 11, the raw materials were mixed, dispersed in a ball mill for 4 hours, and after confirming that the dispersed particle size reached 20 nm at D50, an ultraviolet curable binder (Shin-Etsu Chemical Co., Ltd. X-12- 2400) 10 parts by weight and 1 part of catalyst (DX-2400 manufactured by Shin-Etsu Chemical Co., Ltd.) were mixed and dispersed in a ball mill for 5 hours. It was set to G. This was applied to a PET film (thickness 50 μm) with a bar coater No. 08 so that the dry film thickness was 100 nm, dried at 100 ° C., irradiated with ultraviolet rays, cured, and the refractive index was measured. The results are shown in Fig. 5. A film-forming body having a refractive index of 1.70 was obtained in which the fine particles were 40% by volume or less, the transparency was inferior (haze 14), and the adhesion was inferior.

【0091】

[Table 11]<img file="JP2004123766A_D0011.tif" /> 【0092】

(Comparative Example 5) As shown in Table 12, the raw materials were mixed, dispersed in a ball mill for 4 hours, and after confirming that the dispersed particle size reached 20 nm at D50, an ultraviolet curable binder (Shin-Etsu Chemical Co., Ltd. X-12- 2400) 10 parts by weight and 1 part of catalyst (DX-2400 manufactured by Shin-Etsu Chemical Co., Ltd.) were mixed and dispersed in a ball mill for 5 hours. It was set to H. This was applied to a PET film (thickness 50 μm) with a bar coater No. 08 so that the dry film thickness was 100 nm, dried at 100 ° C., irradiated with ultraviolet rays, cured, and the refractive index was measured. The results are shown in Fig. 5. A film-forming body having a refractive index of 1.59 was obtained, in which the fine particles were 40% by volume or less, the air was 40% by volume or less, the transparency was inferior (haze 21), and the adhesion was inferior.

【0093】

[Table 12]<img file="JP2004123766A_D0012.tif" /> 【0094】

(Application Example) In the application example of the present invention, a low refractive index layer and a high refractive index layer were laminated to form a transparent layer. (Base material) PET (Teijin Jupon's "Teijin Tetron" film highly transparent grade) (hereinafter, # 0 base material) with a thickness of 50 μm, a width of 1000 mm, and a length of 500 m was used. The surface was subjected to a corona discharge treatment to improve the wettability of the slurry. The refractive index was 1.62. (Slurry composition of low refractive index layer) 1 part by weight of silica sol (Nissan Chemical Industries, Ltd. "IPA-ST") with a particle diameter of 10 to 20 nm (average particle diameter 15 nm), isopropyl alcohol as an organic solvent (special grade reagent manufactured by Wako Pure Chemical Industries, Ltd.) 10 parts by weight, as a binder precursor, UV curable binder (manufactured by Shin-Etsu Chemical Industries) X-12-2400) 3 to 10 parts by weight and a catalyst (DX-2400 manufactured by Shin-Etsu Chemical Co., Ltd.) 0.3 to 1 part were mixed and stirred with a stirrer to obtain a solution for a low refractive index layer (# 1 solution). The primary particle size of the silica sol (refractive index 1.45) was almost uniform, and a uniformly dispersed slurry with almost no secondary aggregation was obtained. The film to be formed was almost densely packed with silica, and formed a film containing about 26% of pores having a diameter of 15 nm or less (average pore diameter of 11 nm), and showed a refractive index of 1.35. (Slurry composition of high refractive index layer) High refractive index coating liquid A was used. (Lamination conditions) Eight layers of # 2 solution and # 1 solution were alternately applied to the # 0 substrate by a bar coater. Immediately after application, each layer was dried at 100 ° C. and UV-cured.

【0095】

The reflectances of the obtained film-forming body in the near-infrared wavelength region (760 to 1300 nm) and the visible light region (400 to 750 nm) are obtained to be 0.81 and 0.11. The transmittance was about 3%, that is, the transmittance in the near infrared wavelength region (760 to 1300 nm) was 16%, and the transmittance in the visible light region (400 to 750 nm) was 86%. When the PET film with the optical multilayer film obtained in the application example is attached to the window glass made of float plate glass (made by Asahi Glass, thickness 3 mm), the wavelength in the visible light region of sunlight is transmitted, so refrain from using artificial lights. However, sufficient lighting can be obtained, and since it is difficult to transmit energy in the near-infrared wavelength range, it is possible to suppress the rise in room temperature, which is useful for energy saving.

【0096】

[Effect of the invention]

According to the present invention, the refractive index at the sodium D-line wavelength that can be used to form an economically feasible optical multilayer film having a function such as wavelength selective reflection on a substrate such as glass or plastic is 1.9 or more. A coating composition for forming a film-forming body having a high refractive index film is provided.

[Simple explanation of drawings]

FIG. 1 is a schematic cross-sectional view of the prior art. FIG. 2 is a schematic diagram of a reference of the prior art. FIG. 3 is a diagram showing an electron microscope observation result of a cross section of Example 1.

101 ... organic polymer, 102 ... fine particles, 201 ... organic polymer, 202 ... fine particles, 203 ... air