Article with film, optical device, coating material, and method for manufacturing article

Abstract

To provide an article including a film provided on a surface of an optical device, the film having excellent smudge resistance against smudges such as fingerprints and having excellent heat-shielding properties against sunlight, and a coating material.SOLUTION: An article includes a film formed on a base material, the film at least containing a resin, beads, and titanium oxide, the content of the titanium oxide being 1 / 5 or more of the content of the beads.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an article having a film, an optical device, a coating material, and a method for manufacturing the article, and more particularly to a film, a coating material, and an optical device to be provided on the surface of the lens barrel of an optical device such as a camera, video camera, or broadcasting device, or other optical device such as a camera body that may be used outdoors, a surveillance camera, or a weather camera. [Background technology]

[0002] The coatings applied to the surfaces of optical equipment such as cameras, video cameras, and broadcasting equipment must have both design and functionality. For example, when people touch the surface while taking pictures, fingerprints and oils are likely to adhere to the surface, so anti-fouling properties are required. To make the coatings used on optical equipment less susceptible to fingerprints, they are made hydrophilic, allowing dirt to spread. Alternatively, they can be made hydrophobic, like fluorine. Furthermore, there is known technology that makes the surface uneven, reducing the contact area of ​​dirt and thereby reducing the adhesion of dirt.

[0003] Furthermore, since such optical equipment is often used outdoors, it is required that the material not only be stain-resistant but also have heat-shielding properties to withstand harsh sunlight conditions such as those directly under the equator.

[0004] Patent Document 1 describes a coating material for forming a textured pattern that has enhanced design properties due to the addition of resin beads to the coating material. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 9-302272 Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Document 1, the uneven structure reduces fingerprints and other issues, but the resin beads allow sunlight to pass through, resulting in a low heat-shielding effect.When optical devices are used under harsh sunlight conditions, such as those directly on the equator, deformation of the substrate may result in a decrease in the performance of the optical devices.

[0007] In order to solve the above problems, the present invention aims to provide an article and a coating material having a surface with a film that has excellent antifouling properties to prevent stains such as fingerprints and heat shielding properties against sunlight. [Means for solving the problem]

[0008] The article of the present invention is an article having a substrate and a film provided on the substrate, The membrane comprises: Resin and Titanium oxide and a plurality of beads selected from the group consisting of silica, glass, silicone, and resin; the surface of the film has an uneven structure, The average particle size of the beads is 20 / 7 times or more and 1000 times or less, The content of the beads is 30% by area (%) or more and 42% by area (%) or less, Area content (%) of the titanium oxide of Area content of the beads (%) in The area ratio is 0.46 or more and 0.77 or less, The film has a thickness of 20 μm or more and 70 μm or less. [Effects of the Invention]

[0014] It is possible to provide an article or coating material having a film to be applied to the surface of an optical device, which has excellent antifouling properties to prevent stains such as fingerprints and heat shielding properties against sunlight. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic diagram showing a first embodiment. [Figure 2] FIG. 10 is a diagram illustrating a second embodiment. [Figure 3] 1 is an external view showing an embodiment of an optical device of the present invention. [Figure 4] FIG. 10 is a schematic diagram showing a method for evaluating temperature. DETAILED DESCRIPTION OF THE INVENTION

[0016] Preferred embodiments of the present invention will now be described.

[0017] (First embodiment) Fig. 1 shows a partial cross-sectional view of a first embodiment, which is an example of an article of the present invention. In Fig. 1, 1 is a substrate, and by applying the coating material of this embodiment to a plastic or metal substrate, a film (the film of this embodiment) with excellent heat-shielding performance is formed on the surface.

[0018] In other words, the article of this embodiment has a film (the film according to this embodiment) with excellent heat-shielding properties on its surface. The article of this embodiment is particularly suitable for use in optical devices. Examples of optical devices include interchangeable lenses used in cameras, videos, broadcasting equipment, and the like. Other examples include camera bodies, video bodies, surveillance cameras, weather cameras, and other image forming devices that form images using light transmitted through the lens, which may be used outdoors. When used outdoors, the optical device of this embodiment exhibits a higher heat-shielding effect by forming a film according to this embodiment on the portion (referred to as the outer surface) that is irradiated with sunlight. FIG. 3(a) shows the exterior of an interchangeable camera lens, which is one aspect of the optical device of this embodiment, including a lens barrel with a holder for holding a lens. The interchangeable lens has a lens barrel 30 and a tripod mount 33. The lens barrel 30 is composed of a lens, a fixed barrel 31, an annular member 32, and the like. In the optical device of this embodiment, a film (the film according to this embodiment) with excellent heat-shielding properties is formed on the surfaces of the fixed barrel 31, the annular member 32, the tripod mount 33, and the like of the lens barrel 30. By suppressing thermal deformation of the fixed barrel 31, the annular member 32, the tripod seat 33, etc., it is possible to suppress a decrease in accuracy and form a highly accurate image. The materials of the fixed barrel 31, the annular member 32, and the tripod seat 33 are not particularly limited, and may be plastic or metal.

[0019] The film of this embodiment contains at least a resin 2, beads 3, and titanium oxide 4. The inclusion of the beads 3 makes the surface uneven, making it less susceptible to stains such as fingerprints. In this specification, the beads 3 may be referred to as first particles.

[0020] The material of the beads 3 contained in the film of this embodiment is not particularly limited, and may be inorganic or organic. Preferred inorganic beads are silica, glass, and silicone beads. Preferred organic beads are resin beads, which have high transparency and a low specific gravity. For example, the beads may contain one or more types selected from acrylic resin, epoxy resin, polyester resin, polyolefin resin, polyurethane resin, and melamine resin. The type can be selected depending on the substrate, application, etc.

[0021] In this embodiment, the shape of the beads 3 is preferably spherical in order to form a concave-convex structure. In this specification, spherical means that the average circularity is 0.8 or more. To say that the average circularity is 0.8 or more, first, five samples of the cross section of the film are cut out, and the samples are magnified under a microscope, and the cross sections of 10 beads 3 are observed for each sample. The average circularity of the beads 3 for the 10 beads x 5 samples observed is 0.8 or more. Circularity is calculated using the following formula: Circularity = 4π (area of ​​cross section) / (perimeter of cross section) 2

[0022] In this specification, the cross section of a film is defined as a surface cut in a direction parallel to the normal direction of the film surface. When the film surface has projections and recesses, the normal direction of the film surface is defined as the normal direction of the plane connecting the projections.

[0023] The average particle diameter of the beads 3 is preferably greater than 5 μm and less than 50 μm, more preferably greater than 10 μm and less than 30 μm. When the beads of this embodiment are 5 μm or less, it is difficult to form an uneven structure, and they are more susceptible to dirt adhesion. When the beads are 30 μm or more, they may be exposed from the film surface, which impairs the design. In this specification, beads (first particles) are defined as particles having an average particle diameter of greater than 5 μm and less than 50 μm. The average particle diameter of the beads 3 is the average particle diameter based on the number of particles, and can be measured by dynamic light scattering in the state of the paint before application. When measuring the average particle diameter in the film state, first, five cross-sectional samples of the film according to this embodiment are cut out and enlarged under a microscope. Next, the beads 3 are surface-analyzed at the five locations using Energy Dispersive X-ray Spectroscopy (EDS), and the particle diameters of each bead 3 are determined, and the average value is calculated. In this specification, the particle diameter is defined as the maximum cross-sectional length of the particles. The particle diameter is calculated by determining the diameters of 10 or more particles per location. Finally, the average value of the five points is calculated, and this average value is set as the average particle size of the beads 3 contained in the membrane according to this embodiment.

[0024] The content of beads 3 is preferably 5% by area or more and 80% by area or less, more preferably 30% by area or more and 60% by area or less. If the content of beads 3 is less than 5% by area, the uneven structure may become sparse, which may result in poor antifouling properties. Furthermore, if the content of resin beads exceeds 60% by area, there is a risk of poor adhesion to the substrate. The content of beads contained in the film according to this embodiment can be measured as follows. First, five cross sections of the film according to this embodiment are cut out and enlarged using a microscope. The cross sections of the film are cut in a direction parallel to the normal direction of the film surface. Next, the beads are area-analyzed at the five positions using Energy Dispersive X-ray Spectroscopy (EDS) to calculate the content of beads per unit area. Finally, the content of beads contained in the film according to this embodiment is calculated from the average value of the five positions, and this value is taken as the content (area %) of beads contained in the film. In this specification, the content per unit area is referred to as area content (%) or area %.

[0025] When the film contains beads 3, the surface becomes uneven, making it less susceptible to fingerprints and other stains. However, much of the visible or near-infrared light that affects the heat-shielding performance passes through the beads in the film and reaches the substrate, reducing the overall reflectance and heat-shielding performance. Therefore, light that passes through the beads 3 reaches the substrate, reducing the heat-shielding performance. Therefore, the film of this embodiment is characterized by containing titanium oxide in an amount of 10 to 80 area %, more preferably 30 to 60 area %. Furthermore, the titanium oxide content (area %) is at least one-fifth of the bead content (area %). The titanium oxide of this embodiment has a high solar reflectance, and the solar reflectance of the material alone exceeds 10%. By including titanium oxide in an amount of 10 to 80 area %, more preferably 30 to 60 area %, it is possible to arrange more titanium oxide around the beads. Alternatively, by making the titanium oxide content at least one-fifth of the bead content, it is possible to arrange more titanium oxide around the beads. The inventors have found that this makes it possible for even a film containing beads 3 to exhibit the desired heat-shielding performance.

[0026] Furthermore, the brightness of the film of this embodiment is preferably 20 or more and 95 or less, more preferably 50 or more and 80 or less. Because titanium oxide 4 is white, it is possible to adjust the brightness of the film to 50 or more. In this embodiment, if the brightness of the film is less than 25, the solar reflectance decreases and the temperature reduction effect deteriorates. If the brightness of the film formed using the paint of this embodiment exceeds 95, the color may become too white, making dirt more noticeable.

[0027] Furthermore, the surface of the titanium oxide contained in the film of this embodiment may be coated with silica or the like to block photocatalytic activity in an oxygen-free state.

[0028] The particle size of the titanium oxide is preferably an average particle size of 10 nm or more and 5 μm or less, more preferably 100 nm or more and 3 μm or less. If the average particle size of the titanium oxide of this embodiment is less than 10 nm, the surface area of ​​the particles increases, which may increase the photocatalytic activity and sever the molecular chains of the resin 2, resulting in discoloration. Furthermore, if the average particle size of the titanium oxide of this embodiment exceeds 5 μm, it may be difficult to uniformly disperse the titanium oxide in the film, which may impair the heat-shielding performance.

[0029] The particle size of titanium oxide 4 is the average particle size based on the number of particles, and can be measured by dynamic light scattering in the state of the coating material before application. When measuring in the state of a film, first, five cross-sectional samples of the film according to this embodiment are cut out and enlarged under a microscope. Next, the titanium oxide 4 is area-analyzed at the five locations using Energy Dispersive X-ray Spectroscopy (EDS), the particle size of each titanium oxide 4 is determined, and the average value is calculated. The particle sizes of 10 or more particles per location are determined, and the average value is calculated. Finally, the average value of the five locations is calculated. This average value of the five locations is the average particle size of titanium oxide 4 contained in the film according to this embodiment.

[0030] The content of titanium oxide 4 in the film according to this embodiment can be measured as follows. First, the content (area %) of beads in the film according to this embodiment is calculated using the method described above. Next, five cross sections of the film are cut out from the portion adjacent to the beads and the portion between the beads, which do not contain beads, and are magnified under a microscope. Next, area analysis of titanium oxide is performed on each of the five portions using Energy Dispersive X-ray Spectroscopy (EDS), and the content (area %) of titanium oxide in the area % obtained by subtracting the bead content (area %) from 100% is calculated. For example, if the bead content is 40% by area, the area % obtained by subtracting the bead content (area %) from 100% is 60% by area. If titanium oxide is contained in 50% by area within that 60% by area, the content (area %) of titanium oxide is 30% by area. Finally, the average of the five average values ​​is calculated to determine the content (area %) of titanium oxide in the film.

[0031] (resin) The content of resin 2 contained in the film of this embodiment is preferably 5 area % or more and 80 area % or less, and more preferably 30 area % or more and 60 area % or less. If the content of resin 2 contained in this embodiment is less than 5 area %, adhesion to the substrate may be deteriorated. Furthermore, if the content of resin of this embodiment is more than 60 area %, the uneven structure required for antifouling may not be obtained. Resin 2 contained in the film of this embodiment is not particularly limited, but examples include cured products of epoxy resin, urethane resin, acrylic resin, urethane acrylic resin, phenolic resin, and alkyd resin. The cured product of these resins may be one type, or may contain multiple types.

[0032] The content of resin 2 contained in the film according to this embodiment can be measured as follows. First, the content (area %) of beads contained in the film according to this embodiment is calculated using the method described above. Next, five cross sections of the film not containing beads are cut out and enlarged under a microscope. Next, the resin is area-analyzed at the five locations using Energy Dispersive X-ray Spectroscopy (EDS), and the content (area %) of resin contained in the area % obtained by subtracting the content (area %) of beads from 100% is calculated. For example, if the content (area %) of beads is 40%, the area % obtained by subtracting the content (area %) of beads from 100% is 60%. If the resin is contained in 50% of that 60%, the content (area %) of resin is 30%. Finally, the average value of the five locations is calculated to be the content (area %) of resin contained in the film.

[0033] (base material) Any material can be used as the substrate, but metals and plastics are preferred. Examples of metal materials include aluminum, titanium, stainless steel, magnesium alloys, and lithium-magnesium alloys. Examples of plastic materials include polycarbonate resin, acrylic resin, ABS resin, fluororesin, polyester resin, melamine resin, and vinyl chloride resin.

[0034] The substrate can have any thickness, but it is preferably 0.5 mm to 5 mm, more preferably 0.5 mm to 2 mm. If the thickness is less than 0.5 mm, it becomes difficult to maintain the shape of the lens barrel. If the thickness exceeds 5 mm, the cost of the component increases.

[0035] (Primer) The substrate may have a primer at the interface with the film in order to improve adhesion to the film.

[0036] Any material can be used as the primer, and examples include epoxy resin, urethane resin, acrylic resin, silicone resin, and fluororesin. The primer may contain particles according to this embodiment or particles other than those according to this embodiment. The primer may also contain colorants, dispersants, curing agents, curing catalysts, plasticizers, thixotropic agents, leveling agents, organic colorants, inorganic colorants, preservatives, UV absorbers, antioxidants, coupling agents, and solvent residues.

[0037] The thickness of the primer is preferably 2 μm to 50 μm, more preferably 5 μm to 30 μm. If the thickness is less than 2 μm, the adhesion of the primer may decrease, and if it exceeds 50 μm, the positional accuracy may be adversely affected.

[0038] As used herein, the substrate and the primer may be collectively referred to as the substrate, i.e., as used herein, the substrate may include the primer.

[0039] (film thickness) The film according to this embodiment preferably has a thickness of 20 μm or more and 70 μm or less. If the film thickness is less than 20 μm, the solar reflectance may decrease. If the film thickness is more than 70 μm, the positional accuracy of optical devices may be adversely affected.

[0040] (Particles for adjusting the brightness of films other than titanium oxide) The film according to this embodiment may contain particles (colorants) for adjusting brightness in addition to the titanium oxide 4. While the material of the particles is not particularly limited, known pigments with high infrared reflectivity can be used. For example, quinacridone pigments, perylene pigments, and azo pigments are preferred. Any particles containing an azo group can be used as the azo pigment. The azo pigments contained in the film according to this embodiment can be black, yellow, red, orange, or other colors. Black is preferred because it minimizes color changes (a*, b*) when fading due to sunlight. Furthermore, high sunlight reflectance is preferred, and it is preferable to select a material with a solar reflectance of more than 10% by itself. Examples of azo pigments include nickel azo pigments, insoluble azo pigments, soluble azo pigments, high-molecular-weight azo pigments, and azomethine azo pigments. These azo pigments may be used alone or in combination.

[0041] The average particle size of the azo pigment contained in the film of this embodiment is preferably 10 nm or more and 5 μm or less, more preferably 50 nm or more and 2 μm or less. If the average particle size is less than 10 nm, the surface area of ​​the particles increases, which may result in poor light resistance and discoloration. Furthermore, if the average particle size exceeds 5 μm, it may be difficult to uniformly disperse titanium oxide in the film, which may impair heat-shielding performance. The particle size of the azo pigment is the average particle size based on the number of particles, and can be measured using dynamic light scattering in the paint state before application. Furthermore, when measuring the particle size in the film state, first, five cross-sectional samples of the film of this embodiment are cut out and enlarged using a microscope. The cross-section of the film is preferably cut in a direction parallel to the normal direction of the film surface. Next, the azo pigment is surface-analyzed at five locations using Energy Dispersive X-ray Spectroscopy (EDS), and the particle size of each azo pigment is determined, and the average value is calculated. The particle sizes of 10 or more particles per location are measured, and the average value is calculated. Finally, the average value of the five points is calculated, and this average value is used as the average particle size of the azo pigment contained in the film according to this embodiment.

[0042] The azo pigment content of the film according to this embodiment is preferably 0.1 area % or more and 0.4 area % or less, more preferably 0.15 area % or more and 0.3 area % or less. If the azo pigment content is less than 0.1 area %, the brightness of the film will be too high, resulting in poor antifouling properties. Furthermore, if the azo pigment content is 0.4 area % or more, the brightness of the film will be too low, resulting in poor solar reflectance. The azo pigment content of the film according to this embodiment can be measured as follows: First, the bead content (area %) of the film according to this embodiment is calculated using the method described above. Next, five cross sections of the film that do not contain beads are cut out and enlarged under a microscope. Next, the resin is surface-analyzed at the five points using Energy Dispersive X-ray Spectroscopy (EDS), and the azo pigment content (area %) contained in the area % calculated by subtracting the bead content (area %) from 100% is calculated. For example, if the bead content is 40% by area, subtracting the bead content (area %) from 100% equals 60% by area. If that 60% by area contains 1% by area of ​​azo pigment, the azo pigment content is 0.6% by area. Finally, the average value of the five points is calculated and this is the azo pigment content (area %) in the film.

[0043] (silica particles) The film according to this embodiment may further contain silica particles. The average particle size of the silica is preferably 10 nm or more and 5 μm or less. If the average particle size of the silica according to this embodiment is less than 10 nm, it is difficult to form a surface uneven structure, and dirt is more likely to adhere to the surface. If the average particle size of the silica is 5 μm or more, the unevenness of the coating film becomes large, which may result in a deterioration in film thickness accuracy.

[0044] The silica particles may have any shape. Examples of the shape of the silica particles include spherical, irregular, star-shaped, chain-like, hollow, and porous. These silica particles may be used alone or in combination with one or more types.

[0045] The particle diameter of the silica particles in this embodiment is the average particle diameter based on the number of particles. The average particle diameter of the silica particles can be measured by dynamic light scattering in the state of the coating material before application. When measuring from the state of the film, the bead content (area %) contained in the film according to this embodiment is first calculated using the method described above. Next, five cross sections of the film containing no beads are cut out and enlarged under a microscope. Next, the resin is subjected to area analysis using Energy Dispersive X-ray Spectroscopy (EDS) at the five locations, and the silica particle content (area %) contained in the area % obtained by subtracting the bead content (area %) from 100% is calculated. For example, if the bead content is 40% by area, the area % obtained by subtracting the bead content (area %) from 100% is 60% by area. If 1% by area of ​​silica particles is contained in that 60% by area, the silica particle content is 0.6% by area. Finally, the average value of the five locations is calculated as the silica particle content (area %) contained in the film.

[0046] (Other additives) The film according to this embodiment may contain any other additives, such as dispersants, curing agents, curing catalysts, plasticizers, thixotropy-imparting agents, leveling agents, matting agents, preservatives, ultraviolet absorbers, antioxidants, coupling agents, inorganic and organic fine particles for adjusting color other than those mentioned above, and the like.

[0047] "paint" Next, the paint of this embodiment and the method for producing the paint will be described.

[0048] The paint of this embodiment contains at least a resin, beads, and titanium oxide.

[0049] (beads) The material of the beads contained in the paint of this embodiment is not particularly limited and may be inorganic or organic. Silica, glass, or silicone beads are preferred as inorganic beads. Resin beads, which have high transparency and a low specific gravity, are preferred as organic beads. For example, the paint may contain one or more types selected from acrylic resin, epoxy resin, polyester resin, polyolefin resin, polyurethane resin, and melamine resin.

[0050] The shape of the beads in this embodiment is preferably spherical in order to form a concave-convex structure. The average particle diameter of the beads 3 is preferably 5 μm or more and 50 μm or less, more preferably 10 μm or more and 30 μm or less. If the beads in this embodiment are 5 μm or less, it is difficult to form a concave-convex structure, and they are prone to adhesion of dirt. If the beads are 50 μm or more, there is a risk that the beads may be exposed from the film surface, which will impair the design. The particle diameter of the beads is the average particle diameter based on the number of beads, and can be measured by dynamic light scattering.

[0051] The content of beads contained in the paint of this embodiment is preferably 0.5% by mass or more and 20% by mass or less, more preferably 1% by mass or more and 15% by mass or less, relative to the non-volatile components in the paint. If the bead content is less than 0.5% by mass, the uneven structure may become sparse, which may result in poor anti-fouling properties. Furthermore, if the bead content is 20% by mass or more, there is a risk of poor adhesion to the substrate. The content of beads relative to the non-volatile components in the paint can be measured by centrifuging and separating the beads as sediment.

[0052] (Titanium oxide) The titanium oxide contained in the paint of this embodiment may have its surface coated with silica or the like to block photocatalytic activity in an oxygen-free state.

[0053] The particle size of the titanium oxide is preferably 10 nm or more and 5 μm or less, and more preferably 100 nm or more and 1 μm or less. If the average particle size of the titanium oxide of this embodiment is less than 10 nm, the surface area of ​​the particles increases, which may increase the photocatalytic activity and sever the molecular chains of the resin 2, resulting in discoloration. Furthermore, if the average particle size of the titanium oxide of this embodiment exceeds 5 μm, it may be difficult to uniformly disperse the titanium oxide in the film, which may impair the heat-shielding performance.

[0054] The particle size of the titanium oxide 4 is an average particle size based on the number of particles, and in the case of the state of the coating material before application, it can be measured by a dynamic light scattering method.

[0055] The titanium oxide content of the coating material of this embodiment is preferably 20% by mass or more and 55% by mass or less, more preferably more than 20% by mass and 45% by mass or less, relative to the non-volatile components in the coating material. If the titanium oxide content of this embodiment is less than 20% by mass, the heat-shielding effect decreases. If the content exceeds 55% by mass, it will not be uniformly dispersed in the coating film, causing film unevenness. It can be separated as a sediment by appropriate centrifugation and measured using a Fourier transform infrared spectrophotometer (FT-IR). In this specification, the content relative to the non-volatile components in the coating material will be expressed as mass content (%) or mass %.

[0056] (resin) The resin contained in the coating material of this embodiment is not particularly limited, but examples include epoxy resin, urethane resin, acrylic resin, urethane acrylic resin, phenol resin, and alkyd resin. These resins may be one type or may contain multiple types.

[0057] The resin content of this embodiment is preferably 5% by mass or more and 80% by mass or less, and more preferably 15% by mass or more and 50% by mass or less. If the resin content of this embodiment is less than 5% by mass, adhesion to the substrate may deteriorate. If the resin content of this embodiment is more than 50% by mass, the uneven structure required for antifouling may not be achieved. The resin content relative to the non-volatile components in the coating material can be separated as sediment by appropriate centrifugation and measured using a Fourier transform infrared spectrophotometer (FT-IR).

[0058] (Particles for adjusting the brightness of films other than titanium oxide) The paint of this embodiment may contain particles (colorants) other than titanium oxide to adjust brightness. While the material of the particles is not particularly limited, known pigments with high infrared reflectivity can be used. For example, quinacridone pigments, perylene pigments, and azo pigments are preferred. Any particles containing an azo group can be used as the azo pigment. The azo pigments contained in the paint of this embodiment can be black, yellow, red, orange, etc., with black being preferred because it minimizes color changes (a*, b*) when fading due to sunlight. Furthermore, high sunlight reflectance is preferred, and it is preferable to select a material with a solar reflectance of more than 10% by itself. Examples of azo pigments include nickel azo pigments, insoluble azo pigments, soluble azo pigments, high molecular weight azo pigments, and azomethine azo pigments. These azo pigments may be used alone or in combination.

[0059] The average particle size of the azo pigment contained in the coating material of this embodiment is preferably 10 nm or more and 5 μm or less, and more preferably 50 nm or more and 2 μm or less. If the average particle size is less than 10 nm, the surface area of ​​the particles increases, which may result in poor light resistance and discoloration. Furthermore, if the average particle size exceeds 5 μm, it may be difficult to uniformly disperse titanium oxide in the film, which may impair heat-shielding performance. The particle size of the azo pigment is the average particle size based on number and can be measured by dynamic light scattering.

[0060] The content of the azo pigment contained in the paint of this embodiment is preferably 0.1% by mass or more and 1.0% by mass or less, more preferably 0.15% by mass or more and 0.5% by mass or less, relative to the non-volatile components in the paint. If the content of the azo pigment is less than 0.1% by mass, the film brightness may become too high, which may result in poor antifouling properties. On the other hand, if the content of the azo pigment is 1.0% by mass or more, the film brightness may become too low, which may result in poor solar reflectance. The resin content relative to the non-volatile components in the paint can be separated as a sediment by appropriate centrifugation and measured using a Fourier transform infrared spectrophotometer (FT-IR).

[0061] Particles for adjusting the brightness of the film may contain materials other than titanium oxide and azo pigments, such as alumina, zirconia, silica, hollow silica, zinc oxide, and pigments. These materials may be used alone or in combination. Inorganic and organic fine particles may also be used to adjust the desired brightness, gloss, and color.

[0062] (silica particles) The coating material of this embodiment may further contain silica particles. The average particle size of the silica is preferably 10 nm or more and 5 μm or less. If the average particle size of the silica of this embodiment is less than 10 nm, it is difficult to form a surface uneven structure, and dirt becomes more likely to adhere. If the average particle size of the silica of this embodiment is 5 μm or more, the unevenness of the coating film becomes large, and there is a risk of deterioration in film thickness accuracy.

[0063] The silica particles may have any shape. Examples of the shape of the silica particles include spherical, irregular, star-shaped, chain-like, hollow, and porous. These silica particles may be used alone or in combination with one or more types.

[0064] The particle size of the silica particles in this embodiment is an average particle size based on the number of particles, and the average particle size of the silica particles in the state of the coating material before application can be measured by a dynamic light scattering method.

[0065] The silica particle content is 0.5% by mass or more and 10% by mass or less, and preferably 1% by mass or more and 5% by mass or less, relative to the non-volatile components in the coating material. If the silica content is less than 0.5% by mass, the reflected light from the film surface may adversely affect image quality. Furthermore, if the silica particle content of this embodiment exceeds 10% by mass, there is a risk of sedimentation and accumulation in the coating material. The silica particle content relative to the non-volatile components in the coating material can be measured by separating the sediment using appropriate centrifugation and measuring it with a Fourier transform infrared spectrophotometer (FT-IR).

[0066] (solvent) The paint of this embodiment further contains a solvent.

[0067] The solvent material is not particularly limited, but examples include water, thinner, ethanol, isopropyl alcohol, n-butyl alcohol, ethyl acetate, propyl acetate, isobutyl acetate, and butyl acetate. Other examples include methyl ethyl ketone, methyl isobutyl ketone, propylene glycol monomethyl ether, toluene, xylene, acetone, cellosolves, glycol ethers, and ethers. These solvents may be used alone or in combination.

[0068] The viscosity of the coating material of this embodiment is preferably 10 mPa·s or more and 10,000 mPa·s or less, and more preferably 50 mPa·s or more and 500 mPa·s or less. If the viscosity of the coating material is less than 10 mPa·s, there may be some areas where the thickness of the heat shielding coating after application is thin. Furthermore, if the viscosity exceeds 10,000 mPa·s, there is a risk that the coating material's applicability may be reduced.

[0069] (Other additives) The film according to this embodiment may contain any other additives, such as dispersants, curing agents, curing catalysts, plasticizers, thixotropy-imparting agents, leveling agents, matting agents, preservatives, ultraviolet absorbers, antioxidants, coupling agents, inorganic and organic fine particles for adjusting color other than those mentioned above, and the like.

[0070] <Method for manufacturing paint for application on the upper surface of optical equipment> The method for producing the paint of this embodiment will be described below.

[0071] The method for producing the coating material to be applied to the upper surface of the optical device of this embodiment is not particularly limited as long as it can disperse the resin beads and silica-coated titanium oxide of this embodiment in the coating material. Examples include a bead mill, a ball mill, a jet mill, a three-roller mill, a planetary rotating device, a mixer, an ultrasonic disperser, a homogenizer, and the like.

[0072] <<Production Method of an Article>> In the method for producing an article according to this embodiment, the coating method and curing method are not particularly limited as long as the coating material according to this embodiment can be uniformly applied to a substrate to a thickness of 20 μm or more and 70 μm or less.

[0073] Examples of application methods include brush application, spray application, dip coating, transfer, etc. The film of this embodiment may be a single-layer coating or a multi-layer coating.

[0074] The curing method may involve leaving the composition at room temperature, accelerating the curing with heat, or applying ultraviolet light. Methods for curing the composition by applying heat include a heating furnace, a heater, and infrared heating. The curing temperature is preferably from room temperature to 400°C, and more preferably from room temperature to 200°C.

[0075] In this way, in the article of this embodiment, a film (film according to this embodiment) with excellent heat-shielding properties is formed on the surface of a substrate by applying the coating material of this embodiment to the substrate.

[0076] (Second embodiment) Next, a second embodiment will be described. Note that the same components as those in the first embodiment are given the same reference numerals as those in the first embodiment, and detailed descriptions and drawings thereof will be omitted.

[0077] In the article of this embodiment, a film (film according to this embodiment) with excellent heat-shielding properties is formed on the surface of a plastic or metal substrate by applying the coating material according to this embodiment. In other words, the article of this embodiment has a film (film according to this embodiment) with excellent heat-shielding properties on the surface of the substrate. The film according to this embodiment contains at least resin, resin beads (resin beads), and titanium oxide whose surface is coated with silica. The material of the beads contained in the film of the first embodiment is not particularly limited, but this embodiment solves the problems that arise when resin beads are used. As in the first embodiment, the inclusion of resin beads 7 creates an uneven surface, making it less susceptible to fingerprints and other stains. Furthermore, the titanium oxide added to adjust the color of the film or to enhance the heat-shielding effect is not particularly limited in the first embodiment, but this embodiment is characterized by using titanium oxide whose surface is coated with silica.

[0078] When using resin beads, we found that titanium oxide without a silica surface coating poses the following challenges. Figure 2(a) shows the state of resin beads 7 and titanium oxide 10 when the titanium oxide contained in the film is uncoated titanium oxide 10. When the beads are resin, the resin beads 7 and titanium oxide 10 are attracted to the resin beads 7, which have a negative zeta potential, during the film formation process. However, because titanium oxide 10 has a high positive charge, repulsive forces act between the titanium oxide 10 particles, causing them to separate, making it difficult to coat the beads with titanium oxide 10 (increasing the coverage rate). When the film in this state is exposed to sunlight, the titanium oxide 10 gathers around the beads to a certain extent, reflecting sunlight and providing a certain degree of heat-shielding effect. However, as shown in Figure 2(b), applying tape 5 or the like to the film surface renders the interior of the film oxygen-free. In this oxygen-free state, the titanium oxide 10 located around the resin beads 7 is activated by the photocatalytic action of sunlight, causing deterioration of the resin beads 7. It was found that the film peels off or cracks occur in the deteriorated parts of the resin beads 7.

[0079] Therefore, in this embodiment, it has been discovered that by coating the surface of titanium oxide with silica, deterioration of resin beads due to sunlight in an oxygen-free environment can be prevented.

[0080] As shown in Figure 2(c), the film of this embodiment contains titanium oxide 6 coated on the surface with resin beads 7 and silica 9. In the film, titanium oxide 6 coated with silica 9, which also has a negative zeta potential, is present at a high density (high coverage) around the resin beads 7, which have a negative zeta potential. This is because the high positive value of titanium oxide is alleviated by silica, suppressing the repulsive force, allowing it to be coated around the resin beads 7 at a high density.

[0081] The film of this embodiment can arrange titanium oxide at a high density around the resin beads 7, and therefore can exhibit an excellent heat-shielding effect even if the titanium oxide content in the film is lower than that described in the first embodiment.

[0082] Even when the film of this embodiment is exposed to sunlight, the surrounding titanium oxide reflects the sunlight, maintaining light resistance. Furthermore, even when the film is exposed to sunlight in an oxygen-free environment with tape attached, the silica 9 coating blocks the photocatalytic action of the titanium oxide 6, preventing resin degradation.

[0083] In this way, the film of this embodiment can maintain antifouling properties and light resistance in an oxygen-free environment.

[0084] That is, according to this embodiment, it is possible to provide an article such as an optical device having a film on its surface that has both designability and heat insulation properties and is free from the risk of film peeling or cracking.

[0085] (beads) The resin beads 7 contained in the membrane of this embodiment will be described.

[0086] The material of the resin beads 7 contained in the film of this embodiment is not particularly limited as long as it is resin. For example, one or more types selected from acrylic resin, epoxy resin, polyester resin, polyolefin resin, polyurethane resin, and melamine resin may be used.

[0087] (Silica-coated titanium dioxide) In this specification, titanium oxide 6 particles whose surfaces are coated with silica 9 refer to titanium oxide 6 particles whose surfaces are coated with silica 9 when at least a portion of the surface of the titanium oxide particles 6 is covered with silica 9. The titanium oxide of titanium oxide 6 whose surfaces are coated with silica 9 can be rutile titanium oxide or anatase titanium oxide. It is preferable that 80% or more of the total surface area of ​​titanium oxide 6 whose surfaces are coated with silica 9 is coated with silica 9.

[0088] The content of titanium oxide 6 coated with silica 9 in the film of this embodiment is 5 area % or more and 80 area % or less, more preferably 10 area % or more and 60 area % or less. The content of titanium oxide 6 whose surface is coated with silica 9 is at least 1 / 6 of the content of the beads made of the resin. If the content of titanium oxide coated with silica in this embodiment is less than 5 area %, there is little photocatalytic activity blocking when exposed to sunlight in an oxygen-free state, which may make it impossible to prevent deterioration of the resin beads. If the content exceeds 80 area %, the titanium oxide will not be dispersed uniformly in the coating film, causing film unevenness.

[0089] The content of titanium oxide 4 in the film according to this embodiment can be measured as follows. First, the content (area %) of beads in the film according to this embodiment is calculated using the method described above. Next, five cross sections of the film are cut out from the portion adjacent to the beads and the portion between the beads, which do not contain beads, and are magnified under a microscope. Next, area analysis of titanium oxide is performed on each of the five portions using Energy Dispersive X-ray Spectroscopy (EDS), and the content (area %) of titanium oxide in the area % obtained by subtracting the bead content (area %) from 100% is calculated. For example, if the bead content is 40% by area, the area % obtained by subtracting the bead content (area %) from 100% is 60% by area. If titanium oxide is contained in 50% by area within that 60% by area, the content (area %) of titanium oxide is 30% by area. Finally, the average of the five average values ​​is calculated to determine the content (area %) of titanium oxide in the film.

[0090] The average particle size of the silica-coated titanium oxide of this embodiment is determined by the ratio of its particle size to that of the resin beads. When the average particle size of the silica-coated titanium oxide is defined as 1, the average particle size of the resin beads is preferably in the range of 30 to 300. If the zeta potential difference is less than 30, the silica-coated titanium oxide will not be attracted to the resin beads, and sunlight will pass through the resin beads, potentially reducing the overall reflectance of the film and reducing the heat-shielding effect. If the zeta potential difference is 300 or more, the difference in surface area will be large, resulting in areas on the surface of the resin beads where the silica-coated titanium oxide is not present (uncoated). If such areas are present (uncoated), sunlight will pass through the resin beads, potentially reducing the overall reflectance of the film and reducing the heat-shielding effect.

[0091] From the above average particle size range of the resin beads and the ratio of the average particle size, the average particle size of the silica-coated titanium oxide is preferably 10 nm or more and 5 μm or less, more preferably 100 nm or more and 1 μm or less.

[0092] The substrate, primer, etc. of the article of this embodiment are the same as those of the first embodiment, and therefore their description will be omitted. Also, the resin contained in the film of this embodiment, particles for adjusting the brightness of the film other than silica-coated titanium oxide, silica particles, other additives, film thickness, etc. are the same as those of the first embodiment, and therefore their description will be omitted.

[0093] "paint" Next, the paint of this embodiment will be described.

[0094] The paint of this embodiment contains at least a resin, resin beads, and titanium oxide coated with silica.

[0095] (beads) The material of the resin beads 7 contained in the paint of this embodiment is not particularly limited as long as it is resin. For example, one or more types selected from acrylic resin, epoxy resin, polyester resin, polyolefin resin, polyurethane resin, and melamine resin may be used.

[0096] (Titanium oxide) The average particle size of the silica-coated titanium oxide 6 in this embodiment is determined by the ratio of its particle size to that of the resin beads 7. When the average particle size of the silica-coated titanium oxide 6 is defined as 1, the average particle size of the resin beads is preferably in the range of 30 to 300. If the zeta potential difference is less than 30, the silica-coated titanium oxide 6 will be small, and the silica-coated titanium oxide 6 will not be attracted to the resin beads 7. This will allow sunlight to pass through the resin beads 7, potentially reducing the overall reflectance of the film and decreasing the heat-shielding effect. Furthermore, if the zeta potential difference is 300 or more, the difference in surface area will be large, resulting in the formation of areas on the surface of the resin beads 7 where the silica-coated titanium oxide 6 is not present (is not coated). If such areas are present (are not coated), the resin beads 7 will have areas through which sunlight passes, potentially reducing the overall reflectance of the film and decreasing the heat-shielding effect.

[0097] From the above average particle size range of the resin beads and the ratio of the average particle size, the average particle size of the silica-coated titanium oxide 6 is preferably 10 nm to 5 μm, more preferably 100 nm to 3 μm.

[0098] If the average particle size of the titanium oxide of this embodiment is less than 10 nm, the surface area of ​​the particles increases, which may increase the photocatalytic activity and cut the molecular chains of resin 2, resulting in discoloration. Also, if the average particle size of the titanium oxide of this embodiment is more than 5 μm, it may be difficult to uniformly disperse the titanium oxide in the film, which may impair the heat-shielding performance.

[0099] The average particle diameter of the silica-coated titanium oxide 4 is an average particle diameter based on the number of particles, and in the case of the state of the paint before application, it can be measured by a dynamic light scattering method.

[0100] The content of silica-coated titanium oxide contained in the paint of this embodiment is preferably more than 10% by mass and not more than 55% by mass, more preferably more than 15% by mass and not more than 45% by mass, relative to the non-volatile components in the paint. If the content of silica-coated titanium oxide of this embodiment is less than 10% by mass, the heat-shielding effect will be reduced and there will be less photocatalytic blockage when exposed to sunlight in an oxygen-free environment, which may make it impossible to prevent deterioration of the resin beads. If the content exceeds 50% by mass, the titanium oxide will not be dispersed uniformly within the paint film, causing film unevenness. The content of titanium oxide relative to the non-volatile components in the paint can be measured by separating the sediment by appropriate centrifugation and measuring it with a Fourier transform infrared spectrophotometer (FT-IR).

[0101] The resin, particles for adjusting the brightness of the film other than titanium oxide, silica particles, solvents, and other additives contained in the paint of this embodiment are the same as those in the first embodiment, so their description will be omitted.

[0102] (Other embodiments) FIG. 3(b) shows a cross-sectional view of a single-lens reflex digital camera coupled with an interchangeable lens including a lens barrel having a holder for holding a lens, which is one embodiment of the optical apparatus of the present invention.

[0103] The optical instrument of the present invention refers to an instrument on which the film of the present invention is formed, such as binoculars, microscopes, semiconductor exposure devices, interchangeable lenses, cameras, and other electronic devices, and particularly to an instrument equipped with an optical system including an optical element, or an instrument that generates an image using light that has passed through an optical element.

[0104] The optical device of the present invention may also be a camera system such as a digital still camera or a digital video camera, or an electronic device equipped with an imaging element that receives light that has passed through the optical element of the present invention, such as a mobile phone. Note that the imaging device may also be in the form of a module mounted on an electronic device, for example, a camera module.

[0105] The optical device of the present invention preferably has the film of the present invention with excellent heat-shielding performance (the film according to this embodiment) formed on its exterior, which is exposed to light such as sunlight and is prone to stains such as fingerprints. This prevents stains such as fingerprints and also allows the surface of the optical device to reflect heat such as sunlight, thereby preventing heat from penetrating into the optical device and preventing deformation of precision components installed inside the optical device. This makes it possible to provide an optical device with excellent heat-shielding properties.

[0106] In Figure 3(b), a camera body 602 and an interchangeable lens 601, which is an optical device and includes an outer tube 620 of a lens barrel on which the film of the present invention is formed, are connected, but the interchangeable lens 601 is detachable from the camera body 602.

[0107] Light from the subject passes through an optical system consisting of a plurality of lenses 603, 605, etc. arranged on the optical axis of the photographing optical system in the interchangeable lens 601, and is received by the image sensor.

[0108] Here, lens 605 is supported by lens barrel inner tube 604 and is movably supported relative to lens barrel outer tube 620 for focusing and zooming. By forming the film with excellent heat-shielding performance of the present invention on lens barrel outer tube 620, deformation of lens barrel inner tube 604 is suppressed, and the position of lens 605 supported by lens barrel inner tube 604 can be maintained at a predetermined position.

[0109] During the observation period before shooting, light from the subject is reflected by a main mirror 607 inside the camera body housing 621, passes through a prism 611, and then is projected to the photographer through a viewfinder lens 612 as a shot image. The main mirror 607 is, for example, a half mirror, and light passing through the main mirror is reflected by a sub-mirror 608 toward an AF (autofocus) unit 613. This reflected light is used, for example, for distance measurement. The main mirror 607 is attached and supported by a main mirror holder 640, for example, by adhesive. During shooting, a drive mechanism (not shown) moves the main mirror 607 and sub-mirror 608 out of the optical path, opens a shutter 609, and forms a shot light image incident from the lens barrel 601 on an image sensor 610. The aperture 606 is configured so that the brightness and depth of focus during shooting can be changed by changing the opening area. [Example]

[0110] Preferred embodiments of the present invention will now be described.

[0111] The preparation of the coating material, the formation of the film, and the evaluation of the film in Examples 1 to 3 were carried out by the following methods.

[0112] <How to determine particle size and area content of film> The measurement samples were measured in their film state. The measurement samples were prepared by forming the film of the present invention on a 50 mm x 70 mm square, 1 mm thick polycarbonate resin. The film was applied to a polycarbonate resin plate using a spin coater to the desired film thickness and then baked. The baked film was cut out in a direction parallel to the normal direction of the film surface and observed with a field emission scanning electron microscope (FE-SEM). Next, the target substance was subjected to area analysis using Energy Dispersive X-ray Spectroscopy (EDS), and the particle diameters of each particle were determined by image processing, and the average value was calculated. For beads, the particle diameters of 10 or more particles were determined per location, and the average value was calculated. Finally, the average value of five locations was calculated.

[0113] The content was measured by cutting out five cross sections of the film according to this embodiment and observing them with a field emission scanning electron microscope (FE-SEM). The cross sections of the film were cut in a direction parallel to the normal direction of the film surface. Next, the target substance was analyzed at the five locations using Energy Dispersive X-ray Spectroscopy (EDS), and the content per unit area was calculated by image processing. Finally, the content of the target substance contained in the film according to this embodiment was calculated from the average value of the five locations, and this value was taken as the content (area %) of the target substance contained in the film.

[0114] <Solar reflectance evaluation> The evaluation of solar reflectance will be explained below. The solar reflectance was measured using a spectrophotometer (U-4000, Hitachi High-Tech) and then converted into solar reflectance.

[0115] The reflectance was measured by irradiating light with wavelengths from 300 nm to 2500 nm. Next, the measured reflectance was multiplied by a weighting factor (weighting coefficient) based on JIS-K560 (method of determining solar reflectance of coating film) and integrated, and the solar reflectance was calculated from the integrated value.

[0116] The measurement sample was a 50 mm x 70 mm square, 1 mm thick polycarbonate resin sheet on which the film of the present invention was formed. The film was applied to a polycarbonate resin plate with a spin coater to a desired thickness and then baked.

[0117] Next, cellophane tape (CT-12M; Nichiban) was attached to the top surface of the film. Then, the film was tested using a lightfastness tester (SUNTESTXXL+; ATLAS) at a radiation intensity of 50 ± 2 W / m from 300 to 400 nm. 2 The black panel was left in the test at a temperature of 63°C ± 3°C for 200 hours. After the light resistance test, the cellophane tape was removed from the film and washed with acetone. Within 24 hours, the reflectance was measured using a spectrophotometer at wavelengths from 300 mm to 2500 nm, and the solar reflectance was calculated based on JISK 560.

[0118] In terms of solar reflectance, if the solar reflectance is 60% or higher, the temperature-reducing effect is high and the film can be said to be very good. Also, if the solar reflectance is 50% or higher but less than 60%, the temperature-reducing effect is relatively high and the film can be said to be good. If the solar reflectance is less than 50%, the temperature-reducing effect decreases and the film cannot be said to be good.

[0119] (3-level rating: A to C) A: Solar reflectance is 70% or more B: Solar reflectance is 60% or more but less than 70% C: Solar reflectance is less than 60%

[0120] <Heat-shielding effect> FIG. 4 is a schematic diagram showing a temperature evaluation method. As shown in FIG. 4, a lamp 22, a temperature measurement jig 25, and a temperature evaluation test piece 23 were used for temperature measurement. The temperature evaluation test piece 23 was a 50 mm × 70 mm square, 1 mm thick polycarbonate resin plate coated with the film of the present invention. This polycarbonate resin plate was coated with a spin coater to the desired film thickness and then baked. The temperature measurement jig 25 was a 120 mm × 120 mm × 120 mm cardboard with a natural color surface, and a 40 mm × 40 mm window was provided where the temperature evaluation test piece 23 was attached. The lamp 22 was a Hilux MT150FD6500K (Iwasaki Electric).

[0121] Next, the test piece 23 for temperature evaluation was attached to the temperature measuring jig 25, and a thermocouple was attached to the back surface of the test piece 23 for temperature evaluation. The temperature measuring jig 25 to which the test piece 23 for temperature evaluation was attached was placed so that the distance from the lamp 22 was 100 mm. Next, the lamp 22 was irradiated for 60 minutes, and the temperature after 60 minutes was measured.

[0122] The temperature reduction effect was measured by forming a black blank on the surface of the test piece 23 for temperature evaluation, and the difference between the temperature measurement result of the film of the example was calculated to determine the temperature reduction effect.

[0123] The black blank was made by mixing 20 g of carbon black (MA100, Mitsubishi Chemical) with 100 g of epoxy resin (jER828, Mitsubishi Chemical), 70 g of amine curing agent (ST11, Mitsubishi Chemical), and 20 g of thinner using a planetary rotation device. The mixture was then applied to the surface of the test piece 23 and baked.

[0124] If the temperature reduction effect is 7°C or more, it can be said that the film has an extremely high heat-shielding effect. If the temperature reduction effect is 3°C or more but less than 7°C, it can be said that the film has a relatively high heat-shielding effect. Also, if the temperature reduction effect is less than 3°C, it cannot be said that the film has a good heat-shielding effect.

[0125] (3-level rating: A to C) A: Temperature reduction effect is 7°C or more B: Temperature reduction effect is 3°C or more but less than 7°C C: Temperature reduction effect is less than 3°C

[0126] <Evaluation of antifouling properties of membrane> To evaluate the antifouling properties of the film, a gloss meter (VG7000, Nippon Denshoku Kogyo Co., Ltd.) was used to measure the gloss at 60 degrees. A 50 mm x 70 mm square, 1 mm thick polycarbonate resin film of the present invention was used as the measurement sample. This polycarbonate resin plate was coated with a spin coater to a desired film thickness and then baked. After baking, the gloss value of the film of the present invention was measured using a gloss meter. Next, a fingerprint was left on the sample with a bare hand, and then the gloss value of the film of the present invention was measured. Glossiness change Δ = Glossiness after fingerprint attachment - Glossiness before fingerprint attachment

[0127] If the gloss change Δ is less than 0.5, the film has very little gloss change and is said to have good antifouling effects. If the lightness change is 0.5 or more but less than 1.0, the film has good antifouling effects. If the lightness change is 1.0 or more, the color change is large and the film cannot be said to have good antifouling effects.

[0128] (4-level rating: A to C) A: Gloss change ± less than 0.5 B: Gloss change ±0.5 or more and less than 2.0 C: Gloss change ±2.0 or more

[0129] <Evaluation of film peeling> The measurement sample was a 50 mm x 70 mm square, 1 mm thick polycarbonate resin plate coated with the film of the present invention. The polycarbonate resin plate was coated with a spin coater to a desired thickness and then baked. After baking, cellophane tape (CT-12M; Nichiban) was attached to the top surface of the film of the present invention. Then, the film was tested in a lightfastness tester (SUNTEST XXL+; ATLAS) at a radiation intensity of 50±2 W / m from 300 nm to 400 nm. 2 The black panel was left in the test for 200 hours at a temperature of 63°C ± 3°C. After the light resistance test, the cellophane tape was removed from the film and washed with acetone, and then the film was visually inspected for peeling. A: No film peeling B: Film peeling

[0130] [Example 1] <Paint preparation> In Example 1, a paint was prepared using the following method. 125 g of resin, 0.5 g of azo pigment, and 145 g of titanium oxide (area content: 23%) were weighed out. 40 g of resin beads (area content: 39%), 5 g of silica, 5 g of dispersant, and 100 g of solvent were then weighed out and stirred in a ball mill for 15 hours to obtain a base material. 10 g of the obtained base material was mixed with 1 g of curing agent to obtain the paint of Example 1.

[0131] The resin used was Olester Q-691 (Mitsui Chemicals). The azo pigment used was Chromofine Black A1103 (Dainichiseika Color & Chemicals). The titanium oxide used was PT-301 (Ishihara Sangyo Kaisha; average particle size 0.27 μm, no surface treatment). The resin beads used were MZ-20 (Soken Chemical & Engineering; average particle size 20 μm). The silica used was ACEMATT-OK607. The curing agent used was Takenate D-120N (Mitsui Chemicals).

[0132] <Membrane preparation> In Example 1, a film was prepared by the following method: The above coating material was applied to a polycarbonate plate using a spin coater to form a film of the present invention with a thickness of 30 μm, and the film was dried at room temperature overnight and then baked at 110° C. for 30 minutes to obtain the film of Example 1.

[0133] [Examples 2 to 21] In Examples 2 to 21, coating materials and films were prepared in the same manner as in Example 1 except that the conditions in Tables 1 and 2 were used.

[0134] [Examples 22 to 27] In Examples 23 to 27, paints and films were prepared in the same manner as in Example 1, except that paints were prepared under the conditions shown in Table 3.

[0135] [Table 1]

[0136] [Table 2]

[0137] [Table 3]

[0138] The evaluation results are shown in Tables 4 to 6.

[0139] The film of Example 1 had a solar reflectance of 60% or more, a temperature reduction effect (heat blocking effect) of 7°C or more, which was very good, and an antifouling property (gloss change) of less than ±0.5, which was very good.

[0140] The film of Example 2 used a paint in which the amounts of titanium oxide and beads were adjusted so that the area content of titanium oxide was 17% and the area content of beads was 80% compared to Example 1. The film of Example 2 had a good solar reflectance of 50% or more and less than 60%. The temperature reduction effect (heat blocking effect) was also good, being 3°C or more and less than 7°C. The antifouling properties (gloss change) were also good, being ±0.5 or more and less than 1.0.

[0141] In Example 3, the particle diameter of the beads was changed to 5 μm compared to Example 1, and a paint was used that was adjusted so that the area content of titanium oxide was 23% and the area content of beads was 32%.

[0142] In Example 7, the particle size of the beads was changed to 3 μm and the material of the beads to glass beads, and a coating material was used that was adjusted so that the area content of titanium oxide was 23% and the area content of beads was 30%. The films of Examples 3 and 7 had a solar reflectance of 60% or more and a temperature reduction effect (heat-blocking effect) of 7°C or more, which was very good. The anti-fouling properties (gloss change) were also good, with a range of ±0.5 or more and less than 1.0.

[0143] In Example 4, the particle diameter of the beads was changed to 50 μm compared to Example 1, and a paint was used that was adjusted so that the area content of titanium oxide was 23% and the area content of beads was 40%.

[0144] In Example 5, the particle size of the titanium oxide was changed to 0.01 μm, the bead material was changed to glass beads, and a paint was used that was adjusted so that the area content of titanium oxide was 20% and the area content of beads was 39%, compared to Example 1.

[0145] In Example 6, the particle size of the titanium oxide was changed to 5 μm, the bead material was changed to glass beads, the particle size of the beads was changed to 50 μm, and a paint was used that was adjusted so that the area content of titanium oxide was 25% and the area content of beads was 39%.

[0146] In Example 8, the particle diameter of the beads was changed to 55 μm compared to Example 1, and a paint was used that was adjusted so that the area content of titanium oxide was 23% and the area content of beads was 42%.

[0147] In Example 9, the particle size of the titanium oxide was changed to 0.005 μm, the bead material was changed to glass beads, the particle size of the beads was changed to 5 μm, and a paint was used that was adjusted so that the area content of titanium oxide was 18% and the area content of beads was 39%, compared to Example 1.

[0148] In Example 12, in contrast to Example 1, carbon black was used as a colorant, and a paint was used that was adjusted so that the area content of titanium oxide was 23% and the area content of beads was 39%.

[0149] The films of Examples 4, 5, 6, 8, 9, and 12 had good solar reflectance of 50% or more and less than 60%, and also had good temperature reduction effect (heat blocking effect) at 3°C ​​or more and less than 7°C, and had very good antifouling properties (gloss change) of less than ±0.5.

[0150] In Example 10, the particle diameter of the titanium oxide was changed to 7 μm, the bead material was changed to glass beads, and a paint was used that was adjusted so that the area content of titanium oxide was 27% and the area content of beads was 39%. The film of Example 10 had a very good solar reflectance of 60% or more, a good temperature reduction effect (heat blocking effect) at 3°C ​​or more and less than 7°C, and very good anti-fouling properties (gloss change) of less than ±0.5.

[0151] In Example 11, a perylene-based colorant was used as compared to Example 1, and a paint was used that was adjusted so that the area content of titanium oxide was 23% and the area content of beads was 39%. The film of Example 11, like Example 1, showed very good results in all items.

[0152] As examples according to the second embodiment, Examples 13 to 21 were carried out.

[0153] In Example 13, a paint was used in which the titanium oxide in Example 1 was replaced with titanium oxide whose surface was coated with silica. The film of Example 13 had a solar reflectance of 60% or more, a temperature reduction effect (heat-blocking effect) of 7°C or more, and an antifouling property (gloss change) of less than ±0.5, with no film peeling, and was very good.

[0154] The film of Example 2 used a paint adjusted so that the area content of titanium oxide was 14% and the area content of beads was 80%, compared to Example 13. The film of Example 2 had a good solar reflectance of 50% or more and less than 60%, a good temperature reduction effect (heat blocking effect) of 3°C or more and less than 7°C, and good antifouling properties (gloss change) of ±0.5 or more and less than 1.0, and there was no film peeling.

[0155] In Example 15, the particle diameter of the beads was changed to 5 μm compared to Example 13, and a paint was used in which the area content of titanium oxide was adjusted to 23% and the area content of beads to 32%.

[0156] In Example 18, the particle size of the beads was changed to 3 μm compared to Example 13, and a paint was used in which the area content of titanium oxide was adjusted to 23% and the area content of beads to 30%. The films of Example 15 and Example 18 had a solar reflectance of 60% or more, a very good temperature reduction effect (heat-blocking effect) of 7°C or more, and good antifouling properties (gloss change) of ±0.5 or more and less than 1.0, and there was no film peeling.

[0157] In Example 16, the particle diameter of the beads was changed to 50 μm compared to Example 13, and a paint was used that was adjusted so that the area content of titanium oxide was 23% and the area content of beads was 40%.

[0158] In Example 17, the particle size of the titanium oxide in Example 13 was changed to 0.01 μm, and a paint was used that was adjusted so that the area content of titanium oxide was 20% and the area content of beads was 39%.

[0159] In Example 19, the particle diameter of the beads was changed to 55 μm compared to Example 13, and a paint was used that was adjusted so that the area content of titanium oxide was 23% and the area content of beads was 42%.

[0160] In Example 21, carbon black was used as a colorant in comparison with Example 13, and a paint was used that was adjusted so that the area content of titanium oxide was 23% and the area content of beads was 39%.

[0161] The solar reflectance of the films of Examples 16, 17, 19, and 21 was good at 50% or more and less than 60%, the temperature reduction effect (heat-shielding effect) was also good at 3°C ​​or more and less than 7°C, and the anti-fouling properties (gloss change) were less than ±0.5 and there was no film peeling, so they were very good.

[0162] In Example 20, a perylene-based colorant was used as compared to Example 13, and a paint was used in which the area content of titanium oxide was adjusted to 23% and the area content of beads to 39%. Like Example 13, Example 20 showed very good results in all items.

[0163] In Example 22, a paint was used in which the mass content of titanium oxide relative to the non-volatile components in the paint was adjusted to 20% and the mass content of beads to 10%, as compared to Example 13.

[0164] In Example 25, the particle size of the beads was changed to 50 μm compared to Example 22, and a paint was used in which the mass content of titanium oxide relative to the non-volatile components in the paint was adjusted to 40% and the mass content of beads to 8%.

[0165] In Example 26, the particle size of the titanium oxide was changed to 0.01 μm, the beads were changed to glass beads, and the mass content of the titanium oxide relative to the non-volatile components in the paint was adjusted to 40%, and the mass content of the beads was adjusted to 18%.

[0166] In Example 27, a paint was used in which the particle size of titanium oxide was changed to 5 μm compared to Example 26. The solar reflectance of the films made from the paints of Examples 22, 25, 26, and 27 was good at 50% or more and less than 60%, the temperature reduction effect (heat shielding effect) was also good at 3°C ​​or more and less than 7°C, and the antifouling property (gloss change) was less than ±0.5, which was very good.

[0167] Example 23 used a paint in which the mass content of titanium oxide relative to the non-volatile components in the paint was adjusted to 55% and the mass content of beads to 10%, compared to Example 22. The film produced from the paint of Example 23, like Example 1, showed very good results in all aspects.

[0168] Example 24 used a paint in which the particle size of the titanium oxide was changed to 0.3 μm, the particle size of the beads was changed to 5 μm, and the mass content of the titanium oxide relative to the non-volatile components in the paint was adjusted to 40%, and the mass content of the beads to 15%, compared to Example 26. The film of Example 24 made from the paint of Example 24 had a solar reflectance of 60% or more, a very good temperature reduction effect (heat-blocking effect) of 7°C or more, and good anti-fouling properties (gloss change) of ±0.5 or more and less than 1.0.

[0169] [Table 4]

[0170] [Table 5]

[0171] [Table 6]

[0172] [Comparative Examples 1 to 19] For comparison, the preparation of the paint, the formation of the film, and the evaluation of the film were carried out in the same manner as in the above-mentioned Examples 1 to 19. Tables 7 to 9 show the conditions, amounts added, and content rates of the constituent materials.

[0173] [Table 7]

[0174] [Table 8]

[0175] [Table 9]

[0176] The evaluation results of the comparative examples are shown in Tables 10 to 12.

[0177] In Comparative Example 1, the particle diameter of the beads was changed to 5 μm compared to Example 1, and the amount of titanium oxide and beads was adjusted so that the area content of titanium oxide was 8% and the area content of beads was 62%.

[0178] In Comparative Example 5, the particle diameter of the beads was changed to 3 μm compared to Example 1, and a paint was used in which the area content of titanium oxide was adjusted to 8% and the area content of beads to 62%.

[0179] The films of Comparative Examples 1 and 5 had a solar reflectance of less than 50%, a poor temperature reduction effect (heat shielding effect) of less than 3° C., and poor antifouling properties (gloss change) of ±2.0 or more.

[0180] In Comparative Example 2, the particle diameter of the beads was changed to 50 μm compared to Example 1, and a paint was used in which the area content of titanium oxide was adjusted to 10% and the area content of beads to 85%.

[0181] In Comparative Example 3, the particle size of the titanium oxide in Example 1 was changed to 0.01 μm, and a paint was used in which the area content of titanium oxide was adjusted to 9% and the area content of beads was adjusted to 57%.

[0182] In Comparative Example 4, the particle size of the titanium oxide in Example 1 was changed to 5 μm, and a paint was used in which the area content of titanium oxide was adjusted to 10% and the area content of beads to 53%.

[0183] In Comparative Example 6, the particle diameter of the beads was changed to 55 μm compared to Example 1, and a paint was used in which the area content of titanium oxide was adjusted to 8% and the area content of beads to 42%.

[0184] In Comparative Example 7, the particle size of the titanium oxide was 0.005 μm, the bead material was changed to glass beads, and a paint was used in which the area content of titanium oxide was adjusted to 10% and the area content of beads to 70%.

[0185] In Comparative Example 8, the particle diameter of the titanium oxide in Example 1 was changed to 7 μm, and a paint was used in which the area content of titanium oxide was adjusted to 10% and the area content of beads was adjusted to 55%.

[0186] The films of Comparative Examples 2, 3, 4, 6, 7 and 8 had a solar reflectance of less than 50% and a poor temperature reduction effect (heat shielding effect) of less than 3°C, but the antifouling properties (gloss change) were very good, less than ±0.5.

[0187] Comparative Examples 9 to 15 were carried out as comparative examples related to the second embodiment.

[0188] In Comparative Example 9, the particle size of the beads was changed to 5 μm compared to Example 14, and a paint was used in which the area content of titanium oxide was adjusted to 8% and the area content of beads to 62%. The film of Comparative Example 9 did not peel off where the tape was attached, but the solar reflectance was less than 50%, the temperature reduction effect (heat blocking effect) was poor at less than 3°C, and the antifouling properties (gloss change) were poor at ±2.0 or more.

[0189] In Comparative Example 10, the particle size of the beads was changed to 50 μm compared to Example 14, and a paint was used in which the area content of titanium oxide was adjusted to 13% and the area content of beads to 85%. The film of Comparative Example 10 did not peel off where the tape was attached, but the solar reflectance was less than 50% and the temperature reduction effect (heat shielding effect) was also poor at less than 3°C, but the stain resistance (gloss change) was less than ±0.5 and very good.

[0190] In Comparative Example 11, the particle diameter of the titanium oxide was changed to 0.01 μm and the particle diameter of the beads was changed to 10 μm compared to Example 14, and a paint was used that was adjusted so that the area content of the titanium oxide was 8% and the area content of the beads was 57%.

[0191] In Comparative Example 12, the particle size of the titanium oxide in Example 14 was changed to 5 μm, and a paint was used in which the area content of titanium oxide was adjusted to 8% and the area content of beads to 53%.

[0192] In Comparative Example 14, the particle diameter of the beads was changed to 55 μm compared to Example 14, and a paint was used in which the area content of titanium oxide was adjusted to 8% and the area content of beads to 55%.

[0193] In Comparative Example 15, the particle diameter of the titanium oxide in Example 14 was changed to 7 μm, and a paint was used in which the area content of titanium oxide was adjusted to 10% and the area content of beads was adjusted to 70%.

[0194] The films of Comparative Examples 11, 12, 14, and 15 had a solar reflectance of less than 50% and a poor temperature reduction effect (heat shielding effect) of less than 3°C, but had very good stain resistance (gloss change) of less than ±0.5. However, peeling of the film occurred where the tape was attached.

[0195] In Comparative Example 13, the particle diameter of the beads was changed to 3 μm compared to Example 14, and a paint was used in which the area content of titanium oxide was adjusted to 8% and the area content of beads to 62%.

[0196] The film of Comparative Example 13 had a solar reflectance of less than 50%, a poor temperature reduction effect (heat shielding effect) of less than 3°C, poor stain resistance (gloss change) of ±2.0 or more, and further peeling of the film occurred in the area where the tape was attached.

[0197] In Comparative Example 16, a paint was used in which the mass content of titanium oxide relative to the non-volatile components in the paint was adjusted to 18% compared to Example 22. The film made from the paint of Comparative Example 16 had a solar reflectance of less than 50% and a poor temperature reduction effect (heat shielding effect) of less than 3°C, but the antifouling properties (gloss change) were very good, being less than ±0.5.

[0198] In Comparative Example 17, a paint was used in which the mass content of titanium oxide relative to the non-volatile components in the paint was adjusted to 58% in comparison with Example 22.

[0199] In Comparative Example 19, the particle size of the titanium oxide was changed to 0.01 μm compared to Example 22, and a paint was used in which the mass content of titanium oxide relative to the non-volatile components in the paint was adjusted to 35% and the mass content of beads to 22%. The films made from the paints of Comparative Examples 17 and 19 had a solar reflectance of 60% or more, a very good temperature reduction effect (heat blocking effect) of 7°C or more, and very good anti-fouling properties (gloss change) of less than ±0.5, but peeling of the film occurred where the tape was attached.

[0200] Comparative Example 18 used a paint in which the mass content of titanium oxide relative to the non-volatile components in the paint was adjusted to 35% and the mass content of beads to 0.3%, compared to Example 22. The film made from the paint of Comparative Example 18 did not peel off where the tape was attached, but the solar reflectance was 60% or more and the temperature reduction effect (heat shielding effect) was very good at 7°C or more, but the stain resistance (gloss change) was poor at 1.0 or more.

[0201] [Table 10]

[0202] [Table 11]

[0203] [Table 12] [Industrial Applicability]

[0204] The film formed on the top surface of the optical device of the present invention can be used for the lens barrels of optical devices such as cameras, videos, and broadcasting equipment, as well as other camera bodies, video bodies, surveillance cameras, weather cameras, etc. that may be used outdoors.

Claims

1. An article having a substrate and a film disposed on the substrate, The membrane comprises: Resin and Titanium oxide and a plurality of beads selected from the group consisting of silica, glass, silicone, and resin; the surface of the film has an uneven structure, the average particle size of the beads is 20 / 7 times or more and 1000 times or less than the average particle size of the titanium oxide, The content of the beads is 30% by area or more and 42% by area or less, an area ratio obtained by dividing the area content (%) of the titanium oxide by the area content (%) of the beads is 0.46 or more and 0.77 or less; The article is characterized in that the film has a thickness of 20 μm or more and 70 μm or less.

2. 2. The article according to claim 1, wherein the beads have an average particle size of 5 μm or more and 50 μm or less.

3. 3. The article according to claim 1, wherein the average particle size of the titanium oxide is 10 nm or more and 5 μm or less.

4. 4. The article according to claim 1, wherein the titanium oxide content is 18% by area or more and 27% by area or less.

5. 5. The article according to claim 1, wherein the surface of the titanium oxide is coated with silica.

6. 6. The article according to claim 5, wherein the beads are particles made of resin.

7. 7. The article according to claim 6, wherein the beads are particles made of acrylic resin.

8. 7. The article according to claim 5, wherein the surface of the beads is coated with the titanium oxide whose surface is coated with silica.

9. 9. The article according to claim 5, wherein the area content (%) of the titanium oxide having a surface coated with silica is 1 / 6 or more of the area content (%) of the beads made of resin.

10. 10. The article according to claim 5, wherein the average particle diameter of the resin beads is 30 to 300 times the average particle diameter of the titanium oxide particles whose surfaces are coated with silica.

11. 11. The article of any one of claims 1 to 10, wherein the film further comprises silica particles.

12. 12. The article of claim 1, wherein the substrate comprises a primer.

13. A device comprising an article according to any one of claims 1 to 12, An apparatus characterized in that the film is provided in a portion where light is irradiated.

14. The device has a lens barrel that holds a lens therein, the article is the lens barrel, 14. The device of claim 13, wherein the membrane is disposed on an outer surface of the lens barrel.

Images