JP2017027026A - Glass complex, transparent screen having the same, and image projection system having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a glass complex which, when used for a transparent screen, provides good visibility of both projection light and transmitted light by anisotropically scatter-reflecting the projection light emitted from a light source.SOLUTION: A glass complex for transparent screens of the present invention contains inorganic glass and at least one of photoluminescent flaky fine particles and substantially spherical fine particles.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a glass composite for a transparent screen, and by simultaneously scattering and reflecting the projection light, both the visibility of the projection light and the visibility of the transmitted light are compatible, and further, scratch resistance, wear resistance, and long-term stability. In particular, the present invention relates to a projector screen and a video projection system including the same.

  Conventionally, a combination of a Fresnel lens sheet and a lenticular lens sheet has been used as a projector screen. In recent years, there has been an increasing demand to project and display product information, advertisements, and the like while maintaining transparency on a show window of a department store or a transparent partition of an event space. In the future, it is said that the demand for transparent screens used for head-up displays, wearable displays and the like will increase.

  However, since the conventional projector screen has low transparency, there is a technical problem that it cannot be applied to a transparent partition or the like. Therefore, various screens that can realize high transparency have been proposed. For example, on a plastic film or sheet, an ink containing 7 parts by weight of aluminum scales and 25 parts by weight of pearl pigment scales coated with titanium dioxide using mica as a base is printed or coated, and a light reflecting layer is formed. A reflection type screen characterized by the above has been proposed (see Patent Document 1). Further, on the substrate, light containing 10 to 80 weight of non-feeling type scaly aluminum paste as a light reflecting agent with respect to 100 parts by weight of the binder resin, and further containing 50% or more light diffusing agent with respect to the light reflecting agent. A reflective screen for a projector characterized by providing a diffusion layer has been proposed (see Patent Document 2). Furthermore, a reflective screen has been proposed in which a light diffusing layer formed of a continuous layer made of a transparent resin and a dispersion layer made of anisotropic transparent particles is laminated on a light reflecting substrate. (See Patent Document 3).

Japanese Patent Laid-Open No. 3-119334 JP-A-10-186521 JP 2004-54132 A

  However, the present inventors have found that Patent Documents 1 to 3 have the following technical problems. In the reflection type screen described in Patent Document 1, since the scaly particles are coated on the substrate surface at a high concentration, the image cannot be clearly seen due to the glare of the coating film, and a white vinyl chloride film is used for the substrate. Therefore, there is a technical problem that fluoroscopy is impossible. The reflective screen described in Patent Document 2 contains a scaly aluminum paste at a high concentration of 10 to 80 weight as a light reflector, and has a technical problem that the obtained film cannot be seen through. In the reflective screen described in Patent Document 3, anisotropic transparent particles dispersed in a dispersion layer are non-metallic particles of mica, talc, and montmorillonite. In particular, since talc and montmorillonite are clay-based particles, regular reflectance is obtained. However, there is a technical problem that it cannot be suitably used as a reflective transparent screen. Furthermore, although the screens described in Patent Documents 1 to 3 have improved scratch resistance and antifouling properties to some extent, they are peeled off from the scratched part once they are scratched because they are organic material coating layers. In addition, there is a problem that the fingerprint is difficult to wipe off due to the interaction between the coating layer and the oil component of the fingerprint, and higher scratch resistance, wear resistance, long-term stability, and antifouling properties are desired.

  The present invention has been made in view of the above technical problems, and its purpose is to provide excellent visibility of projected light and visible light of transmitted light by anisotropically scattering and reflecting the projected light, and a viewing angle is increased. Broadly, the object is to provide a glass composite for a transparent screen that has further improved scratch resistance and antifouling properties and does not deteriorate with time even when used for a long time. Another object of the present invention is to provide a transparent screen including the glass composite, and an image projection system including the glass composite or the transparent screen and a projection device.

  As a result of intensive investigations to solve the above technical problem, the present inventors have dispersed the above-mentioned technical problem by dispersing at least one of glittering flaky fine particles or substantially spherical fine particles in an inorganic glass. It was found that a glass composite that can be suitably used for a transparent screen is obtained. The present invention has been completed based on such findings.

That is, according to one aspect of the present invention,
Provided is a glass composite for a transparent screen comprising inorganic glass and at least one of glittering flaky fine particles or substantially spherical fine particles.

  In the aspect of the present invention, it is preferable that an average diameter of primary particles of the glittering flaky fine particles is 0.01 to 100 μm.

  In the aspect of the present invention, the specular reflectance of the glittering flaky fine particles is preferably 12% or more.

  In the aspect of the present invention, the average aspect ratio of the glittering flaky fine particles is preferably 3 to 800.

  In an aspect of the present invention, the glittering flaky fine particles are made of aluminum, copper, tin-cobalt alloy, silver, platinum, gold, titanium, nickel, tin, indium, chromium, titanium oxide, aluminum oxide, and zinc sulfide. It is preferably a metallic particle selected from the group consisting of: a glittering material in which glass is coated with a metal or a metal oxide; or a glittering material in which natural mica or synthetic mica is coated with a metal or metal oxide.

  In the aspect of the present invention, the inorganic glass is preferably at least one selected from the group consisting of water glass, a sol-gel material, and a glass material having a softening temperature of 150 to 650 ° C.

  In the aspect of this invention, it is preferable that content of the said glittering flaky fine particle is 0.01-5.0 mass% with respect to the said inorganic glass.

In the embodiment of the present invention, the difference between the refractive index n ₂ of the substantially spherical fine particles and the refractive index n ₁ of the inorganic glass is expressed by the following mathematical formula (1):
| N ₁ −n ₂ | ≧ 0.1 (1)
It is preferable to satisfy.

  In the aspect of the present invention, the substantially spherical fine particles are preferably at least one selected from the group consisting of zirconium oxide, titanium oxide, zinc oxide, cerium oxide, barium titanate, and strontium titanate.

  In the aspect of the present invention, the median diameter of the primary particles of the substantially spherical fine particles is preferably 0.1 to 100 nm.

  In the aspect of the present invention, the content of the substantially spherical fine particles is preferably 0.0001 to 2.0% by mass with respect to the inorganic glass.

  In the aspect of the present invention, the glass composite is preferably for a transmissive transparent screen or a reflective transparent screen.

  According to the other aspect of this invention, the laminated body of a glass composite provided with the glass composite of this and a base material is provided.

  According to another aspect of the present invention, there is provided a reflective transparent screen comprising the above glass composite.

  According to another aspect of the present invention, there is provided a transmission type transparent screen provided with the above glass composite.

  According to another aspect of the present invention, there is provided a vehicle member provided with the glass composite, the transmissive transparent screen, or the reflective transparent screen.

  According to another aspect of the present invention, there is provided a building member comprising the glass composite, the transmissive transparent screen, or the reflective transparent screen.

  According to another aspect of the present invention, there is provided a video projection system including the glass composite, the transmissive transparent screen, or the reflective transparent screen, and a projection device.

  When used as a transparent screen, the glass composite for a transparent screen according to the present invention can project a clear image on the transparent screen by anisotropically reflecting and reflecting the projection light without impairing the transparency. Excellent viewing angle, and excellent scratch resistance, abrasion resistance, antifouling resistance, and long-term stability. That is, the glass composite according to the present invention can achieve both the visibility of projected light and the visibility of transmitted light, and can be suitably used as a transparent screen. Furthermore, such a transparent screen can be suitably used for glass windows, head-up displays, wearable displays, and the like.

It is a cross-sectional schematic diagram of the thickness direction of one Embodiment of the glass composite body by this invention. 1 is a schematic diagram illustrating an embodiment of a transparent screen and a video projection system according to the present invention.

<Glass composite>
The glass composite according to the present invention comprises inorganic glass and at least one of glittering flaky fine particles or substantially spherical fine particles, and further laminates other layers such as an antireflection layer, an adhesive layer, and a substrate. May be. By using at least one of glittering flaky fine particles or substantially spherical fine particles, which will be described later, light can be scattered and reflected anisotropically in the glass composite to improve the viewing angle. Inorganic glass has excellent scratch resistance and is a chemically stable material, so that it does not easily change over time when used for a long time. In particular, when particles having photoactivity, such as titanium oxide, are dispersed as resin in the form of glittering flaky fine particles or substantially spherical fine particles, deterioration of the resin is promoted and there is a possibility that it cannot be used for a long time. In the present invention, by using inorganic glass, it is possible to produce a transparent screen that can be used for a long time even when fine particles having photoactivity are used.

  The glass composite according to the present invention can be seen through and can be suitably used as a transparent screen. The glass composite according to the present invention has excellent visibility of projection light and visibility of transmitted light by anisotropically scattering and reflecting the projection light, wide viewing angle, high transparency, and excellent scratch resistance. It has wear resistance and long-term stability. Such a glass composite can be suitably used as a reflective transparent screen used for a head-up display, a wearable display, and the like. In the present invention, the term “transparent” is sufficient as long as the transparency can be realized according to the application, and includes “translucent”.

  FIG. 1 shows a schematic cross-sectional view in the thickness direction of one embodiment of the glass composite according to the present invention. The glass composite laminate 15 includes a glass composite 13 in which glittering flaky fine particles 11 and substantially spherical fine particles 12 are dispersed in an inorganic glass 10, and a base material 14. Such a laminated body of the glass composite 15 scatters the projection lights 16 and 17 anisotropically, so that the viewer 19 can visually recognize the scattered light 18.

  The glass composite preferably has a haze value of 50% or less, more preferably 1% or more and 40% or less, more preferably 1.3% or more and 30% or less, and even more preferably 1.5%. It is 20% or less and most preferably 2% or more and 10% or less. The total light transmittance is preferably 70% or more, more preferably 75% or more, still more preferably 80% or more, and even more preferably 85% or more. When the haze value is within the above range, the transparency is high, the transmission visibility can be further improved, and the performance as a screen is excellent. In the present invention, the haze value of the glass composite is based on JIS-K-7361 and JIS-K-7136 using a turbidimeter (manufactured by Nippon Denshoku Industries Co., Ltd., product number: NDH-5000). Can be measured.

The glass composite preferably has a reflected front luminous intensity of 3 or more and 60 or less, more preferably 4 or more and 50 or less, and still more preferably 4.5 or more and 40 or less. In the glass composite, a value obtained by multiplying the transmitted front light intensity by 1000 is preferably 1.5 or more, more preferably 2.0 or more, and even more preferably 3.0 or more and 50 or less. . If the value obtained by multiplying the reflection front brightness and transmission front brightness by 1000 in the glass composite is within the above range, the brightness of the reflected light is high and the performance as a reflective screen is excellent. In the present invention, the reflected light intensity and the reflected light intensity improvement rate of the glass composite are values measured as follows.
(Reflected front brightness)
The measurement was performed using a variable angle photometer (Nippon Denshoku Industries Co., Ltd., product number: GC5000L). The incident angle of the light source was set to 45 degrees, and the reflected light intensity in the 0 degree direction when a standard white plate with a whiteness of 95.77 was placed on the measurement stage was set to 100. At the time of sample measurement, the incident angle of the light source was set to 15 degrees, and the intensity of reflected light in the 0 degree direction was measured.
(Transmission front brightness)
The measurement was performed using a variable angle photometer (Nippon Denshoku Industries Co., Ltd., product number: GC5000L). The incident angle of the light source was set to 0 degree, and the transmitted light intensity in the 0 degree direction when nothing was placed on the measurement stage was set to 100. In the sample measurement, the incident angle of the light source was set to 15 degrees, and the intensity of transmitted light in the 0 degree direction was measured.

  The image clarity of the glass composite is preferably 70% or more, more preferably 75% or more, still more preferably 80% or more, still more preferably 85% or more, and particularly preferably 90%. % Or more. If the image clarity of the glass composite is within the above range, the image seen through the transparent screen is very clear. In the present invention, the image clarity is a value of image definition (%) when measured with an optical comb width of 0.125 mm in accordance with JIS K7374.

  The thickness of the glass composite is not particularly limited, but is preferably from 0.1 μm to 20 mm, more preferably from 0.5 μm to the viewpoint of application, productivity, handleability, and transportability. 15 mm, and more preferably 1 μm to 10 mm.

(Inorganic glass)
As the inorganic glass forming the glass composite, it is preferable to use those having good dispersibility of glittering flaky fine particles or substantially spherical fine particles, which will be described later, water glass, sol-gel material, or fine glass powder having a low softening point It is particularly preferred to use a dispersion of Since these glass materials are in a liquid state, the dispersibility of the glittering flaky fine particles or the substantially spherical fine particles is good and the moldability is excellent. In this specification, the glass composite may be a fine particle-dispersed glass (glass composite) obtained by curing a liquid inorganic glass by a curing reaction such as sintering or sol-gel hydrolysis. Fine particle-dispersed glass (glass composite) in which fine particles are dispersed in inorganic glass (silica sand, soda ash, glass waste such as limestone or cullet) and cooled may be used.

(Water glass)
Water glass refers to a concentrated aqueous solution of alkali silicate, and sodium is usually included as an alkali metal. A typical water glass can be represented by Na ₂ O.nSiO ₂ (n: any positive number). Commercially available water glass has n in the range of 2-4. Commercially available water glasses include Nos. 1 to 3 as aqueous sodium silicate solutions, and the ratio of SiO ₂ to Na ₂ O increases in this order. When the water is evaporated from the water glass, a solid material having a moisture content of about 10 to 30% by mass, which is called Japanese water glass, is formed which is hard to break and has elasticity, and functions as an adhesive binder. In some cases, K ₂ O may be partially contained instead of Na ₂ O, but even in this case, the molar ratio with SiO ₂ is preferably in the above range. The function as a binder tends to form a coating film with high mechanical strength as the molecular weight of the polysilicate ion contained in the water glass increases, but cracks may easily form in the coating film. It is preferable to use water glass contained in an optimum molar ratio of SiO _{2 to} Na ₂ O depending on the concentration and pH of the water glass contained in use, the ratio to hydroxyapatite, and the like. As the water glass, sodium silicate manufactured by Fuji Chemical Co., Ltd. can be used.

(Sol-gel material)
The sol-gel material is a group of compounds that are cured by hydrolysis polycondensation by the action of heat, light, catalyst, and the like. For example, metal alkoxide (metal alcoholate), metal chelate compound, metal halide, liquid glass, spin-on glass, or a reaction product thereof, which may contain a catalyst that accelerates the curing reaction. Moreover, you may have a photoreactive functional group, such as an acryl group, in a part of metal alkoxide functional group. The sol-gel material may be used alone or in combination of a plurality of types depending on the required physical properties. The cured film of the sol-gel material refers to a state in which the polymerization reaction of the sol-gel material has sufficiently progressed. The sol-gel material is chemically bonded and strongly bonded to the surface of the inorganic substrate in the course of the polymerization reaction. Therefore, a stable glass composite can be formed by using a cured film of a sol-gel material as the glass composite.

  A metal alkoxide is a compound group obtained by reacting an arbitrary metal species with water or an organic solvent using a hydrolysis catalyst, etc., and an arbitrary metal species and a hydroxy group, methoxy group, ethoxy group, propyl group, isopropyl It is a group of compounds in which a functional group such as a group is bonded. Examples of the metal species of the metal alkoxide include silicon, titanium, aluminum, germanium, boron, zirconium, tungsten, sodium, potassium, lithium, magnesium, tin and the like.

  Examples of the metal alkoxide having a silicon species of silicon include dimethyldiethoxysilane, diphenyldiethoxysilane, phenyltriethoxysilane, methyltriethoxysilane, vinyltriethoxysilane, p-styryltriethoxysilane, methylphenyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane (MTES), 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3 -Methacryloxypropyltriethoxysilane, 3-acryloxypropyltriethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldiethoxysilane, N-2- (aminoethyl) -3-aminopro Lutriethoxysilane, 3-aminopropyltriethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropylmethyldiethoxysilane, 3-mercaptopropyltriethoxysilane, triethoxysilane (TEOS), diphenylsilanediol, dimethylsilane Examples thereof include diols, and compound groups in which the ethoxy groups of these compound groups are replaced with methoxy groups, propyl groups, isopropyl groups, hydroxy groups, and the like. Among these, TEOS, tetramethoxysilane (TMOS) in which the ethoxy group of TEOS is replaced with a methoxy group, and MTES are particularly preferable. These may be used alone or in combination of a plurality of types.

  When TEOS, MTES or a mixture thereof is used, the mixing ratio can be 1: 1, for example, in a molar ratio. This sol solution produces amorphous silica by performing hydrolysis and polycondensation reactions. In order to adjust the pH of the solution as a synthesis condition, an acid such as hydrochloric acid or an alkali such as ammonia may be added. The pH is preferably 4 or less or 10 or more. Moreover, you may add water in order to perform a hydrolysis. The amount of water to be added can be 1.5 times or more in molar ratio with respect to the metal alkoxide species.

Moreover, as a metal alkoxide, a silsesquioxane compound can also be used. Silsesquioxane is a general term for a group of compounds represented by SiO _1.5 , and is a compound in which one organic group and three oxygen atoms are bonded to one silicon atom. The metal halide is a group of compounds in which the functional group that undergoes hydrolytic polycondensation is replaced with a halogen atom in the metal alkoxide.

  Examples of metal chelate compounds include titanium diisopropoxy bisacetylacetonate, titanium tetrakisacetylacetonate, titanium dibutoxybisoctylene glycolate, zirconium tetrakisacetylacetonate, zirconium dibutoxybisacetylacetonate, aluminum trisacetylacetonate, Examples thereof include aluminum dibutoxy monoacetylacetonate, zinc bisacetylacetonate, indium trisacetylacetonate, and polytitanium acetylacetonate.

  Examples of the liquid glass include TGA series manufactured by Apollo Ring Co., and other sol-gel compounds can be added depending on the required physical properties. As the spin-on glass, for example, an OCD series manufactured by Tokyo Ohka Co., an ACCUGLASS series manufactured by Honeywell, or the like can be used.

  Various acids and bases can be used as the catalyst for proceeding with the curing. Various acids include not only inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid but also organic acids such as various carboxylic acids, unsaturated carboxylic acids and acid anhydrides. Moreover, when hardening is photocuring, the photoinitiator, photoacid generator, photosensitizer, etc. which are used in UV curable resin can be used.

  The sol-gel material may contain a solvent. Suitable solvents include, for example, alcohols such as methanol, ethanol, isopropyl alcohol (IPA), butanol and 2-butanol, aliphatic hydrocarbons such as hexane, heptane, octane, decane and cyclohexane, benzene, toluene, xylene, Aromatic hydrocarbons such as mesitylene, ethers such as diethyl ether, tetrahydrofuran and dioxane, ketones such as acetone, methyl ethyl ketone, isophorone and cyclohexanone, butoxyethyl ether, hexyloxyethyl alcohol, methoxy-2-propanol, benzyloxyethanol Ether alcohols such as ethylene glycol, glycols such as propylene glycol, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, Glycol ethers such as propylene glycol monomethyl ether acetate, esters such as ethyl acetate, ethyl lactate and γ-butyrolactone, phenols such as phenol and chlorophenol, N, N-dimethylformamide, N, N-dimethylacetamide, N- Examples include amides such as methylpyrrolidone, halogen-based solvents such as chloroform, methylene chloride, tetrachloroethane, monochlorobenzene, and dichlorobenzene, hetero-containing compounds such as carbon disulfide, water, and mixed solvents thereof. In particular, ethanol and isopropyl alcohol, or a solvent obtained by mixing them with water is preferable.

  For sol-gel materials, polyethylene glycol, polyethylene oxide, hydroxypropyl cellulose, polyvinyl alcohol and alkanolamines such as triethanolamine which are solution stabilizers, β-diketones such as acetylacetone, β-ketoesters, formamide, Dimethylformamide, dioxane and the like may be applied.

(Low softening point glass material)
The low softening point glass material preferably has a softening temperature in the range of 150 to 620 ° C, more preferably in the range of 200 to 600 ° C, and most preferably in the range of 250 to 550 ° C. As a glass material in such a range, PbO—B ₂ O ₃ series, PbO—B ₂ O ₃ —SiO ₂ series, PbO—ZnO—B ₂ O ₃ series, a mixture containing an acid component and a metal chloride is heat-treated. The lead-free low softening point glass etc. which are obtained by doing can be used. Among these, it is preferable to use lead-free low softening point glass having particularly low environmental pollution. The low softening point glass material is preferably a so-called glass frit that dissolves in a curing step described later. Further, as the low softening point glass material, it is preferable to use a powder having a median diameter in the range of 1 to 50 μm. In order to improve the dispersibility and moldability of the fine particles, a binder, a polar solvent, a high boiling point organic solvent, and the like can be mixed in the low softening point glass material.

  As the binder, urethane resin, acrylic resin, acrylic silicon resin, non-chlorinated polyolefin resin, polyester resin, cellulose acetate, and the like can be used. Among them, acrylic resin and cellulose acetate are particularly preferable. As for the density | concentration of a binder, 0.2-40 mass parts is preferable with respect to the mass of a low softening point glass material, More preferably, it is 0.5-20 mass parts, More preferably, it is 1-10 mass parts.

  The polar solvent is preferably water, alcohol (methanol, ethanol, isopropyl alcohol, etc.), acetone, methyl ethyl ketone, butyl acetate, ethyl acetate, petroleum ether or the like. The amount of the solvent used is preferably 100 to 900 parts by mass, more preferably 150 to 800 parts by mass, and still more preferably 200 to 500 parts by mass with respect to the mass of the low softening point glass material.

  The high boiling point organic solvent is not particularly limited, and mineral oil, vegetable oil, synthetic drying oil and the like can be used. Propionate, higher alkyl ester, pine oil and the like are preferably used. The high boiling point organic solvent is preferably 1 to 20 parts by mass, more preferably 2 to 15 parts by mass, and further preferably 3 to 10 parts by mass with respect to the mass of the low softening point glass material.

(Bright flaky fine particles)
As the glittering flaky fine particles, a glittering material that can be processed into a flaky shape can be suitably used. The regular reflectance of the glittering flaky fine particles is preferably 12.0% or more, more preferably 15.0% or more, and further preferably 20.0% or more and 80.0% or less. In the present invention, the regular reflectance of the glittering flaky fine particles is a value measured as follows.
(Regular reflectance)
A spectrocolorimeter (manufactured by Konica Minolta Co., Ltd., product number: CM-3500d) was used. Lubricated flaky fine particles dispersed in an appropriate solvent (water or methyl ethyl ketone) were formed on a slide glass with a film thickness of 0.00. The coated glass plate was coated and dried so as to have a thickness of 5 mm or more.Specular reflectance when light was incident on the coating film from the glass surface at an angle of 45 degrees with respect to the normal of the glass surface. By measuring the regular reflectance when the brilliant flaky fine particles are used as a coating film, the reflection performance of the brilliant flaky fine particles in consideration of the oxidation state and the like of the surface of the fine particles can be grasped.

As the metal material used for the metal-based fine particles, a metal having excellent projection light reflectivity is used. Specifically, the metal material preferably has a reflectance R at a measurement wavelength of 550 nm of 50% or more, more preferably 55% or more, still more preferably 60% or more, and even more preferably 70% or more. It is. Hereinafter, in the present invention, “reflectance R” refers to the reflectance when light is incident on a metal material from the vertical direction. The reflectance R can be calculated by the following formula (1) using the refractive index n and the extinction coefficient k, which are intrinsic values of the metal material. n and k are, for example, in Handbook of Optical Constants of Solids: Volume 1 (by Edward D. Palik), PB Johnson and RW Christy, PHYSICAL REVIEW B, Vol. 6, No. 12, 4370-4379 (1972), etc. Have been described.
R = {(1-n) ² + k ² } / {(1 + n) ² + k ² } Formula (1)
That is, the reflectance R (550) at a measurement wavelength of 550 nm can be calculated from n and k measured at a wavelength of 550 nm. The metal material has an absolute value of the difference between the reflectance R (450) at the measurement wavelength 450 nm and the reflectance R (650) at the measurement wavelength 650 nm within 25% of the reflectance R (650) at the measurement wavelength 550 nm. Yes, preferably within 20%, more preferably within 15%, and even more preferably within 10%. By using such a metal material, when used as a reflective transparent screen, the reflection of projected light and color reproducibility are excellent, and the performance as a screen is excellent.

In the metal material used for the metal-based fine particles, the real term ε ′ of the dielectric constant is preferably −60 to 0, and more preferably −50 to −10. The real term ε ′ of the dielectric constant can be calculated by the following formula (2) using the values of the refractive index n and the extinction coefficient k.
ε ′ = n ² −k ² formula (2)
Although the present invention is not bound by any theory, when the real term ε ′ of the dielectric constant of the metal material satisfies the above numerical range, the following action occurs, and the transparent light scatterer is used as a reflective transparent screen. It is thought that it can be used suitably. That is, when light enters the metal-based fine particles, an oscillating electric field is generated in the metal-based fine particles, but at the same time, reverse electric polarization occurs due to free electrons of the metal-based fine particles, thereby shielding the electric field. When the real light ε ′ of the dielectric constant is 0 or less, the light is completely shielded so that the light cannot enter the metal-based fine particles, that is, there is no diffusion due to surface irregularities and no light absorption by the metal-based fine particles. Assuming an ideal state, all light is reflected on the surface of the metal-based fine particles, so that the light reflectivity is strong. When ε ′ is larger than 0, the vibration of free electrons in the metal-based fine particles cannot follow the vibration of light, so the vibration electric field due to light cannot be completely canceled, and the light enters the metal-based fine particles, It is transparent. As a result, only a part of the light is reflected on the surface of the metal-based fine particles, and the light reflectivity is lowered.

As the metal material, any metal material satisfying the above-described reflectance R, preferably further satisfying the dielectric constant may be used, and a pure metal or an alloy can also be used. The pure metal is preferably selected from the group consisting of aluminum, silver, platinum, titanium, nickel, and chromium. As the metal-based fine particles, fine particles made of these metal materials, or fine particles obtained by coating these metal materials with resin, glass, natural mica, or synthetic mica can be used. In addition, the shape of the metal-based fine particles is not particularly limited, and flaky fine particles, substantially spherical fine particles, and the like can be used. For various metal materials, the refractive index n and extinction coefficient k at each measurement wavelength are summarized in Table 1, and the reflectances R and ε ′ calculated using the values are summarized in Table 2.

  Depending on the type of inorganic glass to be dispersed, the glittering flaky fine particles are, for example, metallic fine particles such as aluminum, silver, copper, platinum, gold, titanium, nickel, tin, tin-cobalt alloy, indium and chromium. Or metallic fine particles composed of titanium oxide, aluminum oxide and zinc sulfide, a glittering material in which glass or metal or metal oxide is coated, or a glittering material in which natural or synthetic mica is coated with metal or metal oxide. Can be used.

  The glittering flaky fine particles preferably have an average primary particle diameter of 0.01 to 100 μm, more preferably 0.05 to 80 μm, still more preferably 0.1 to 50 μm, and still more preferably 0.5 to 30 μm. . Further, the bright flaky fine particles preferably have an average aspect ratio (= average diameter / average thickness of the bright flaky fine particles) of preferably 3 to 800, more preferably 4 to 700, still more preferably 5 to 600, and still more preferably. Is 10-500. When the average diameter and average aspect ratio of the glittering flaky fine particles are within the above ranges, a sufficient scattering effect of projection light can be obtained without impairing transmission visibility when the glass composite is used for a transparent screen. Thus, a clear image can be projected. In the present invention, the average diameter of the glittering flaky fine particles was measured using a laser diffraction particle size distribution measuring device (manufactured by Shimadzu Corporation, product number: SALD-2300). The average aspect ratio was calculated from an SEM (trade name: SU-1500, manufactured by Hitachi High-Technologies Corporation) image.

  As the glittering flaky fine particles, commercially available ones may be used, and for example, Daiwa Metal Powder Co., Ltd. aluminum powder, Matsuo Sangyo Co., Ltd. metal-coated glass (Metashine series) can be suitably used. .

  The content of the glittering flaky fine particles in the glass composite can be appropriately adjusted according to the regular reflectance of the glittering flaky fine particles, and is preferably 0.0001 to 5.0 mass with respect to the inorganic glass. %, Preferably 0.0005 to 3.0 mass%, more preferably 0.001 to 1.0 mass%. Projection light is produced by anisotropically scattering and reflecting the projection light emitted from the light source by dispersing the glittering flaky fine particles in the inorganic glass at a low concentration within the above range to form a glass composite. And the visibility of transmitted light can be improved.

(Substantially spherical fine particles)
The substantially spherical fine particles may include true spherical particles, or may include spherical particles having irregularities and protrusions. Refractive indices n ₁ and substantially the refractive index n ₂ of the spherical fine particles of an inorganic glass, the following equation (1):
| N ₂ −n ₁ | ≧ 0.1 (1)
It is preferable to satisfy the following formula (2):
| N ₂ −n ₁ | ≧ 0.15 (2)
It is more preferable to satisfy the following formula (3):
3.0 ≧ | n ₂ −n ₁ | ≧ 0.2 (3)
It is further preferable to satisfy When the refractive indexes of the inorganic glass and the substantially spherical fine particles forming the glass composite satisfy the above mathematical formula, light can be scattered anisotropically in the glass composite and the viewing angle can be improved. Further, by using substantially spherical fine particles, light can be scattered omnidirectionally and luminance can be improved.

As the substantially spherical fine particles having a high refractive index, for example, the refractive index n ₂ is preferably 1.80 to 3.55, more preferably 1.9 to 3.3, and still more preferably 2.0 to It is possible to use metal-based particles having a metal oxide or metal salt size of 3.0. Examples of the metal oxide include zirconium oxide (ZrO ₂ , n = 2.40), zinc oxide (ZnO ₂ , n = 2.40), titanium oxide (TiO ₂ , n = 2.72), and cerium oxide. (CeO ₂ , n = 2.20) and the like. Examples of the metal salt include barium titanate (BaTiO ₃ , n = 2.40) and strontium titanate (SrTiO ₃ , n = 2.37). These substantially spherical fine particles can be used singly or in combination of two or more.

The median diameter of the primary particles of the substantially spherical fine particles is preferably 0.1 to 100 nm, more preferably 0.2 to 70 nm, and still more preferably 0.5 to 50 nm. When the median diameter of the primary particles of the substantially spherical fine particles is within the above range, when used as a transparent screen, a sufficient diffusion effect of the projection light can be obtained without impairing transmission visibility. Video can be projected. In the present invention, the median diameter (D ₅₀ ) of the primary particles of the inorganic fine particles was measured by a dynamic light scattering method using a particle size distribution analyzer (trade name: DLS-8000, manufactured by Otsuka Electronics Co., Ltd.). It can be determined from the particle size distribution.

  The content of substantially spherical fine particles can be appropriately adjusted according to the thickness of the glass composite and the refractive index of the fine particles. The content of fine particles in the glass composite is preferably 0.0001 to 2.0% by mass, more preferably 0.001 to 1.0% by mass, and still more preferably 0% with respect to the inorganic glass. 0.005 to 0.5 mass%, and still more preferably 0.01 to 0.3 mass%. If the content of substantially spherical fine particles in the glass composite is within the above range, while ensuring the transparency of the glass composite, by sufficiently diffusing the projection light emitted from the projection device anisotropically, The visibility of diffused light and the visibility of transmitted light can both be achieved.

The concentration of the glittering flaky fine particles and / or the substantially spherical fine particles with respect to the inorganic glass is such that the thickness of the glass composite is t (μm), and the glittering flaky fine particles and / or the substantially spherical fine particles with respect to the inorganic glass. When the fine particle concentration is c (mass%), t and c are expressed by the following formula (I):
0.05 ≦ (t × c) ≦ 50 (I)
Preferably satisfying
0.1 ≦ (t × c) ≦ 40 (I-2)
More preferably,
0.15 ≦ (t × c) ≦ 35 (I-3)
More preferably,
0.3 ≦ (t × c) ≦ 30 (I-4)
Even more preferably. When the thickness t and the concentration c of the glass composite satisfy the above formula (I), the dispersion state of the fine particles in the glass composite is sparse (the concentration of the fine particles in the glass composite is low). By increasing the ratio of transmitted light (increasing the ratio of light that does not collide with fine particles), it is possible to display a clear image on the screen without impairing the visibility of transmitted light. When two or more kinds of glittering flaky fine particles and / or substantially spherical fine particles are contained, the concentration c is the total concentration of all fine particles.

  Although the thickness of a glass complex is not specifically limited, Preferably it is 0.01 micrometer-1 mm, More preferably, it is 0.1 micrometer-500 micrometers, More preferably, it is 1 micrometer-300 micrometers. If the thickness of the cured film is within the above range, the function as a transparent screen can be sufficiently exhibited. The glass composite may have a single layer structure or a multilayer structure in which two or more layers are laminated by coating or the like.

  The glass composite preferably has a scratch hardness measured according to JIS-K5600-5-4 (scratch hardness method) of HB or higher, more preferably H or higher, and scratch resistance of 2H or higher. More preferably.

(Antireflection layer)
The antireflection layer is a layer for improving image visibility by reducing the reflection phenomenon of external light and the reflection of incident light from the projector on the surface of the layer. Further, the antireflection layer suppresses that part of the light emitted from the light source is reflected on the screen surface, and as a result, the amount of light incident on the glass composite increases, and thus has a luminance improving effect. The antireflection layer may be laminated on the viewer side of the glass composite, or may be laminated on both sides. The antireflection layer may be a single layer, or may be a multilayer laminate of resins having different refractive indices in order to prevent reflection in the entire wavelength region.

  The antireflection layer can be formed using a resin that does not impair the transmission visibility and desired optical properties of the glass composite. As such a resin, for example, a resin curable by ultraviolet rays or an electron beam, that is, an ionizing radiation curable resin, a mixture of an ionizing radiation curable resin and a thermoplastic resin and a solvent, and a thermosetting resin are used. Among these, ionizing radiation curable resins are particularly preferable.

The antireflection layer may be formed of a thin film layer of an inorganic material such as a metal and a metal oxide that does not impair the transmission visibility and desired optical properties of the glass composite. As the inorganic material, it is not particularly limited, evaporation ease, taking into account the light-transmitting, for _{example, TiO 2 (n = 2.72)} , ZrO 2, (n = 2.40), SiO ₂ (n = 1.46), magnesium fluoride (MgF ₂ , (n = 1.39), calcium fluoride (CaF ₂ , (n = 1.39), CeO ₂ (n = 2.45), oxidation Tin (SnO ₂ , n = 2.30), tantalum oxide (V) (Ta ₂ O ₅ , n = 2.12), indium oxide (In ₂ O ₃ n = 2.00), and the like can be given.

  The thickness of the antireflection layer is preferably 50 nm to 100 μm, more preferably 80 nm to 80 μm, and still more preferably 90 nm to 100 μm. When the thickness of the antireflection layer is in the above range, an excellent antireflection function can be imparted while maintaining high transparency.

(Base material)
The substrate is a support for forming the glass composite into a thin film. Specifically, the base material is a substrate made of an inorganic material such as metal, ceramics, soda glass, quartz glass, sapphire substrate, quartz, silicon substrate, polyethylene terephthalate (PET), polyethylene telenaphthalate (PEN), polycarbonate (PC ), Cycloolefin polymer (COP), polymethyl methacrylate (PMMA), polystyrene (PS), polyimide (PI), polyarylate and the like can be used. Although the substrate may be transparent or opaque, for example, a base material that is optically transparent in the visible light region of 400 nm to 780 nm can be used as it is as a transparent screen, and can be used for various optical applications other than the screen. Particularly preferred. When used in the ultraviolet region, it is preferable to use a base material containing quartz glass or sapphire glass having a high ultraviolet transmittance. In order to improve adhesion, a surface treatment or an easy-adhesion layer may be provided on the substrate, and a gas barrier layer may be provided for the purpose of preventing intrusion of a gas such as moisture or oxygen. When the curing reaction includes a high-temperature process such as sintering, it is preferable to use a material that does not soften or damage at a high temperature. Specifically, a glass substrate having a softening temperature of 600 ° C. or higher is preferable, a glass substrate of 650 ° C. or higher is more preferable, and a glass substrate of 700 ° C. or higher is most preferable. The substrate may be a flat plate or any shape depending on the purpose of use. In addition, the thickness of a base material can be suitably changed according to a use and material so that the intensity | strength may become appropriate. For example, it may be in the range of 10 μm to 1 mm (1000 μm), and may be a thick plate of 1 mm or more.

(Adhesive layer)
An adhesion layer is a layer for sticking a base material, an antireflection layer, etc. to at least one side of a glass complex. It is also possible to prepare a laminated structure in which an adhesive layer is provided on both surfaces of a glass composite and the glass composite is sandwiched between substrates. The pressure-sensitive adhesive layer is preferably formed using a pressure-sensitive adhesive composition that does not impair the transmission visibility and desired optical properties of the glass composite. Examples of the pressure-sensitive adhesive composition include natural rubber, synthetic rubber, poly (meth) acrylic, polyvinyl ether, polyurethane, polysilicon, polyvinyl alcohol, and the like. Specific examples of synthetic rubbers include styrene-butadiene rubber, acrylonitrile-butadiene rubber, polyisobutylene rubber, isobutylene-isoprene rubber, styrene-isoprene block copolymer, styrene-butadiene block copolymer, styrene-ethylene-butylene block. A copolymer is mentioned. Specific examples of polyvinyl alcohol include polyvinyl butyral and ethylene-vinyl acetate resin. Specific examples of the polysilicone-based material include dimethylpolysiloxane. Among these, a polyvinyl alcohol adhesive and an acrylic adhesive are preferable. These pressure-sensitive adhesives can be used singly or in combination of two or more.

  The acrylic resin pressure-sensitive adhesive is a polymer containing at least a (meth) acrylic acid alkyl ester monomer. Generally, it is a copolymer of a (meth) acrylic acid alkyl ester monomer having an alkyl group having about 1 to 18 carbon atoms and a monomer having a carboxyl group. In addition, (meth) acrylic acid means acrylic acid and / or methacrylic acid. Examples of (meth) acrylic acid alkyl ester monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, sec-propyl (meth) acrylate, (meth) acrylic acid. n-butyl, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth) acrylic acid Examples thereof include n-octyl, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, undecyl (meth) acrylate, and lauryl (meth) acrylate. Moreover, the said (meth) acrylic-acid alkylester is normally copolymerized in the ratio of 30-99.5 mass parts in the acrylic adhesive.

  Moreover, as a monomer which has a carboxyl group which forms acrylic resin adhesive, the monomer containing carboxyl groups, such as (meth) acrylic acid, itaconic acid, crotonic acid, maleic acid, monobutyl maleate, and (beta) -carboxyethyl acrylate Can be mentioned.

  In addition to the above, the acrylic resin pressure-sensitive adhesive may be copolymerized with a monomer having another functional group within a range not impairing the characteristics of the acrylic resin pressure-sensitive adhesive. Examples of monomers having other functional groups include monomers containing hydroxyl groups such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and allyl alcohol; (meth) acrylamide, N-methyl Monomers containing amide groups such as (meth) acrylamide and N-ethyl (meth) acrylamide; Monomers containing amide groups and methylol groups such as N-methylol (meth) acrylamide and dimethylol (meth) acrylamide; Monomers having functional groups such as amino group-containing monomers such as meth) acrylate, dimethylaminoethyl (meth) acrylate and vinylpyridine; epoxy group-containing monomers such as allyl glycidyl ether and (meth) acrylic acid glycidyl ether -Etc. In addition, fluorine-substituted (meth) acrylic acid alkyl ester, (meth) acrylonitrile and the like, vinyl group-containing aromatic compounds such as styrene and methylstyrene, vinyl acetate, and vinyl halide compounds can be used.

  Commercially available adhesives may be used, such as SK Dyne 2094, SK Dyne 2147, SK Dyne 1811L, SK Dyne 1442, SK Dyne 1435, and SK Dyne 1415 (above, manufactured by Soken Chemical Co., Ltd.), Olivain EG-655, Olivevine BPS5896 (above, manufactured by Toyo Ink Co., Ltd.), etc. (above, trade name) can be suitably used.

<Method for producing glass composite>
The method for producing a glass composite according to the present invention is not particularly limited, and using a glass composite material in which at least one of glittering flaky fine particles or substantially spherical fine particles is dispersed in an inorganic glass, A glass composite can be formed by a conventionally known molding method. For example, the method for producing a glass composite according to the present invention includes (1) a step of producing an inorganic glass solution in which at least one of glittering flaky fine particles or substantially spherical fine particles, an inorganic glass, and a solvent are mixed; A step of applying an inorganic glass solution to a substrate to form a coating film; (3) a step of drying the solvent; and (4) a step of curing the coating film. The glass composite is industrially produced by dispersing the fine particles in an inorganic glass melted at a high temperature such as a float process or a roll-out process, and molding and cooling to produce a plate-like glass composite. You can also.

(1) Inorganic glass solution preparation process The inorganic glass solution is a mixture of at least one of glittering flaky fine particles or substantially spherical fine particles, inorganic glass, and a solvent, and a binder, a high-boiling organic solvent, a catalyst, or the like as necessary. Is added and dispersed. Since the inorganic glass solution is a solid dispersion, long-term storage stability is not always sufficient. Accordingly, a paste containing at least one of glittering flaky fine particles or substantially spherical fine particles, inorganic glass, and optionally a binder, a catalyst, and a high boiling point organic solvent is prepared in advance, and the solvent is added to the paste at the time of use. It is preferable to add and disperse to prepare a glass material solution. In this case, the paste can be prepared by a known dispersion method.

  The dispersion method is not particularly limited, and can be carried out using a dispersion apparatus usually used for dispersing pigments. Dispersing devices include dispersers, homomixers, planetary mixers, etc., homogenizers (manufactured by M Technique Co., Ltd., trade name: CLEARMIX, PRIMIX Co., Ltd., trade name: Philmix), ball mill, sand mill (Shinmaru Enterprise) Manufactured by Susu Co., Ltd .: trade name: Dino Mill), attritor, wet jet mill (produced by Genus Co., Ltd .: trade name Genus PY, medialess disperser (produced by Nara Machinery Co., Ltd., trade name MICROS), and other roll mills.

(2) Application process The prepared inorganic glass solution is applied to the substrate by a known method such as spin coating, dip coating, bar coating, flow coating, roll coating, spray coating, die coating, ink jet, gravure coating, etc. It can be carried out. Of these, bar coating, die coating, and spin coating are preferred from the viewpoint that the sol-gel solution can be uniformly applied to a relatively large substrate and that the application can be completed quickly before the sol solution is cured.

(3) Drying step After the coating step, the substrate is held in the air or under reduced pressure in order to evaporate the solvent in the coated film. If this holding time is short, the solvent remains and the durability deteriorates. The holding temperature is preferably in the range of 10 to 200 ° C, more preferably in the range of 10 to 100 ° C. When the holding temperature is higher than this range, it is not preferable because the curing reaction proceeds rapidly, and when the holding temperature is lower than this range, the curing reaction is required for a long time.

(4) Curing Step The curing reaction is preferably performed at 200 to 700 ° C., although it depends on the type of inorganic glass. At 200 ° C. or lower, the curing becomes insufficient, so the strength of the glass composite after curing is lowered. Above 700 ° C, the substrate may be damaged. The curing time is preferably about 5 minutes to 1 hour, and more preferably about 10 to 30 minutes. At temperatures of 450 ° C. or higher, the glittering flaky fine particles or substantially spherical fine particles may start to be oxidized. Therefore, when a curing reaction is performed in such a temperature range, a low oxygen atmosphere (such as nitrogen gas or argon gas) It is preferably carried out in an active gas or in a vacuum.

<Transparent screen>
A transparent screen according to the present invention comprises the above glass composite. The transparent screen may be composed only of the above glass composite, may be used as it is a substrate coated with an inorganic glass solution, or may further be provided with a support such as a transparent partition. The transparent screen may be a flat surface, a curved surface, or an uneven surface.

  The transparent screen according to the present invention may be a rear projection screen (transmission screen) or a front projection screen (reflection screen). That is, in the video display device including the transparent screen according to the present invention, the position of the light source may be on the side opposite to the viewer (transmission type screen) or on the viewer side (reflection type). screen). Such a transparent screen has excellent visibility of projected light and transmitted light by anisotropically scattering and reflecting the projected light emitted from the light source, wide viewing angle, and excellent anti-glare properties and brightness. It is what you have.

  The transparent screen preferably has a haze value of 50% or less, more preferably 1% or more and 40% or less, still more preferably 1.3% or more and 30% or less, and even more preferably 1.5% or more. 20% or less. The transparent screen preferably has a total light transmittance of 70% or more, more preferably 75% or more, still more preferably 80% or more, and even more preferably 85% or more. The transparent screen preferably has a diffuse transmittance of 1.5% to 60%, more preferably 1.7% to 55%, and more preferably 1.9% to 50%. Yes, even more preferably 2.0% or more and 45% or less. If the haze value and the total light transmittance are within the above ranges, the transparency is high and transmission visibility can be further improved. If the diffuse transmittance is within the above ranges, the incident light is efficiently diffused. Since the viewing angle can be further improved, the performance as a screen is excellent. In the present invention, the haze value, the total light transmittance and the diffuse transmittance of the transparent screen are JIS-K-7361 and turbidimeter (manufactured by Nippon Denshoku Industries Co., Ltd., product number: NDH-5000). It can be measured according to JIS-K-7136.

  The image clarity of the transparent screen is preferably 70% or more, more preferably 75% or more, still more preferably 80% or more, still more preferably 85% or more, and particularly preferably 90%. That's it. If the image clarity of the transparent screen is within the above range, the image seen through the transparent screen is very clear. In the present invention, the image clarity is a value of image definition (%) when measured with an optical comb width of 0.125 mm in accordance with JIS K7374.

The transparent screen preferably has a reflected front luminous intensity of 3 or more and 60 or less, more preferably 4 or more and 50 or less, and still more preferably 4.5 or more and 40 or less. Further, the transparent screen has a value obtained by multiplying the transmitted front luminous intensity by 1000, preferably 1.5 or more, more preferably 2.0 or more, and still more preferably 3.0 or more and 50 or less. If the value obtained by multiplying the reflective front luminous intensity and the transmitted front luminous intensity of the transparent screen by 1000 is within the above range, the brightness of the reflected light is high and the performance as a reflective screen is excellent. In the present invention, the reflected light intensity and the reflected light intensity improvement rate of the transparent screen are values measured as follows.
(Reflected front brightness)
The measurement was performed using a variable angle photometer (Nippon Denshoku Industries Co., Ltd., product number: GC5000L). The incident angle of the light source was set to 45 degrees, and the reflected light intensity in the 0 degree direction when a standard white plate with a whiteness of 95.77 was placed on the measurement stage was set to 100. At the time of sample measurement, the incident angle of the light source was set to 15 degrees, and the intensity of reflected light in the 0 degree direction was measured.
(Transmission front brightness)
The measurement was performed using a variable angle photometer (Nippon Denshoku Industries Co., Ltd., product number: GC5000L). The incident angle of the light source was set to 0 degree, and the transmitted light intensity in the 0 degree direction when nothing was placed on the measurement stage was set to 100. In the sample measurement, the incident angle of the light source was set to 15 degrees, and the intensity of transmitted light in the 0 degree direction was measured.

(Support)
The support is for supporting the glass composite. The support may be any material that does not impair the transmission visibility and desired optical properties of the transparent screen. Examples thereof include a transparent partition, a glass window, a head-up display for passenger cars, and a wearable display.

<Vehicle members>
A vehicle member according to the present invention comprises the above-described glass composite or transparent screen. Examples of the vehicle member include a windshield and a side glass. By providing the glass composite or the transparent screen, the vehicle member can display a clear image on the vehicle member without providing a separate screen.

<Building materials>
The building member according to the present invention comprises the above glass composite or transparent screen. Examples of the building member include a window glass of a house, a glass wall of a convenience store, a road surface store, and the like. Since the building member includes the glass composite or the transparent screen, a clear image can be displayed on the building member without providing a separate screen.

<Video projection system>
A video projection system according to the present invention includes the above glass composite or a reflective screen that can be seen through, and a projection device. The projection device is not particularly limited as long as it can project an image on a screen. For example, a commercially available front projector can be used.

  A schematic diagram of one embodiment of a transparent screen and video projection system according to the present invention is shown in FIG. The transparent screen 23 includes a transparent partition (support) 22 and a laminated body 21 of a glass composite on the viewer 24 side on the transparent partition 22. The laminated body 21 of the glass composite may include an adhesive layer in order to stick to the transparent partition 22. In the case of a transmissive screen, the video projection system includes a transparent screen 23 and a projection device 25 </ b> A installed on the opposite side (back side) of the viewer 24 with respect to the transparent partition 22. The projection light 26A emitted from the projection device 25A enters from the back side of the transparent screen 23 and is anisotropically scattered by the transparent screen 23, so that the viewer 24 can visually recognize the scattered light 27A. In the case of a reflective screen, the video projection system includes a transparent screen 23 and a projection device 25B installed on the same side (front side) as the viewer 24 with respect to the transparent partition 22. The projection light 26B emitted from the projection device 25B enters from the front side of the transparent screen 23 and is anisotropically scattered by the transparent screen 23, so that the viewer 24 can visually recognize the scattered light 27B.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is limited to the following Example and is not interpreted.

In Examples and Comparative Examples, various physical properties and measuring methods for performance evaluation are as follows.
(1) Haze Using a turbidimeter (manufactured by Nippon Denshoku Industries Co., Ltd., product number: NDH-5000), the haze of a glass composite laminate (with a quartz glass substrate) described later in accordance with JIS K7136. Was measured. Furthermore, the haze of only the quartz glass used as the base material is measured, and the haze value of the glass composite is calculated by subtracting the haze value of the quartz glass base material from the haze value of the laminate of the glass composite (with the quartz glass base material). (Since the haze value of the glass plate is almost 0, the haze value of the glass composite is not substantially affected).
(2) Total light transmittance Using a turbidimeter (manufactured by Nippon Denshoku Industries Co., Ltd., product number: NDH-5000), based on JIS K7361-1, a laminated body of glass composite (with quartz glass substrate) ) Was measured.
(3) Diffuse transmittance Using a turbidimeter (manufactured by Nippon Denshoku Industries Co., Ltd., product number: NDH-5000), a laminated body of glass composite (with quartz glass substrate) according to JIS K7361-1. The diffuse transmittance was measured.
(4) Reflected frontal light intensity Measured using a variable angle photometer (manufactured by Nippon Denshoku Industries Co., Ltd., product number: GC5000L). The incident angle of the light source was set to 45 degrees, and the reflected light intensity in the 0 degree direction when a standard white plate with a whiteness of 95.77 was placed on the measurement stage was set to 100. At the time of sample measurement, the incident angle of the light source was set to 15 degrees, and the intensity of reflected light in the 0 degree direction was measured.
(5) Transmitted frontal light intensity Measured using a variable angle photometer (manufactured by Nippon Denshoku Industries Co., Ltd., product number: GC5000L). The incident angle of the light source was set to 0 degree, and the transmitted light intensity in the 0 degree direction when nothing was placed on the measurement stage was set to 100. In the sample measurement, the incident angle of the light source was set to 15 degrees, and the intensity of transmitted light in the 0 degree direction was measured.
(6) Viewing angle It was measured using a variable angle photometer (Nippon Denshoku Industries Co., Ltd., product number: GC5000L). The incident angle of the light source was set to 0 degree, and the transmitted light intensity in the 0 degree direction when nothing was placed on the measurement stage was set to 100. At the time of sample measurement, the transmitted light intensity from −85 degrees to +85 degrees was measured in increments of 1 degree with the incident angle of the light source kept at 0 degrees. The viewing angle was defined as a range where the transmitted light intensity was 0.001 or more in the measurement range.
(7) Regular reflectance Spectra colorimeter (manufactured by Konica Minolta Co., Ltd., product number: CM-3500d) Measured using glittering flaky fine particles dispersed in an appropriate solvent (water or methyl ethyl ketone) on a slide glass The film was coated and dried so that the film thickness was 0.5 mm or more, and light was incident on the coating from the glass surface at an angle of 45 degrees with respect to the normal of the glass surface. The specular reflectance was measured.
(8) Image clarity Image clarity (%) when measured with an image comb width of 0.125 mm in accordance with JIS K7374 using a image clarity measuring device (manufactured by Suga Test Instruments Co., Ltd., product number: ICM-1T). The value of) was defined as image clarity. The larger the image sharpness value, the higher the transmission image clarity.
(9) Scratch hardness JIS-K5600-5-4 The hardness was evaluated about the glass complex using the scratch hardness method.
(10) Screen performance Mobile LED mini manufactured by Onkyo Digital Solutions Co., Ltd. from a position 50 cm away from the normal direction of the glass composite to the glass composite prepared as a transparent screen below. An image was projected using the projector PP-D1S. Next, after adjusting the focus knob of the projector so that it is in focus on the surface of the screen, the images projected on the glass composite from two places, 1 m ahead and 1 m behind the glass composite, are visually observed. Evaluation was made visually based on the following criteria. Observation from the front of the screen can evaluate the performance as a reflection type screen, and observation from the back can evaluate the performance as a transmission type screen.
[Evaluation criteria]
A: The image could be seen very clearly.
○: The image was clearly visible.
(Triangle | delta): The outline and hue of an image | video were visually recognized with a little blur.
X: The outline of the image was blurred and unsuitable for use as a screen.

[Example 1]
(1) Inorganic glass solution preparation process Water glass (sodium silicate aqueous solution, Kishida Chemical Co., Ltd. product name: Water Glass No. 3) was prepared as an inorganic glass material. 0.13% by mass of flaky aluminum fine particles A (average primary particle diameter 1 μm, aspect ratio 25, regular reflectance 16.8%) as sodium silicate as glittering flaky fine particles was added to the water glass, Furthermore, the inorganic glass solution A was obtained by adding isopropyl alcohol and stirring at 23 degreeC and humidity 45% so that a sodium silicate density | concentration might be 20 mass%.
(2) Coating step A quartz glass plate (100 × 100 × 2 mm, Ya = 83%, Tg = 63%, T1500 = 59%, T850 = 47%, haze ratio = washed with the inorganic glass solution A as a substrate 0%) was applied using a bar coater. A doctor blade (manufactured by YOSHIMITSU SEIKI) was used as the bar coater. This doctor blade was designed to have a coating film thickness of 5 μm, but a 35 μm thick imide tape was applied to the doctor blade to adjust the coating film thickness to 40 μm. A coating film was obtained.
(3) Drying step The coated glass plate was heat-treated on a hot plate at 100 ° C. for 10 minutes to dry the coating film. The film thickness after drying was 7 μm.
(4) Curing step The coating film obtained in the drying step is dried at room temperature, further heated and dried in a drying furnace at 250 ° C. for 10 minutes, and provided with a glass composite and a substrate (quartz glass plate). A laminate of glass composites was formed. When the cross section was confirmed with a transmission electron microscope (TEM), the thickness of the obtained glass composite was 5 μm.
(5) Evaluation of transparent screen When the laminate of the produced glass composite was used as it was as a transparent screen, the haze value was 4.7%, the diffuse transmittance was 4.1%, and the total light transmittance was It was 88.1%, the image clarity was 91%, the scratch hardness was 6H, and it had high transparency and scratch resistance.
Moreover, the transmission front luminous intensity (* 1000) measured with the goniophotometer was 1.08, and it turned out that it is excellent in the transmission front luminous intensity. The reflected front brightness measured with a goniophotometer was 9.6, and it was found that the reflected front brightness was excellent. The viewing angle measured with a goniophotometer was ± 16 degrees, and it was found that the viewing angle characteristics were excellent. Further, the surface formed with the glass composite was difficult to attach fingerprints and could be easily wiped even if the fingerprints were attached. Furthermore, when the screen performance was evaluated, it was possible to visually recognize a clear image during both the front observation and the rear observation, and in particular, it was possible to visually recognize a very clear image during the front observation.

[Example 2]
(1) Inorganic glass solution preparation step In a solution obtained by mixing 530 parts by mass of ethanol, 45 parts by mass of water and 0.2 parts by mass of concentrated hydrochloric acid, 54.3 parts by mass of tetraethoxysilane (TEOS) as a sol-gel material, and methyltriethoxy 45.7 parts by mass of silane (MTES) was added dropwise, and flaky aluminum fine particles A as bright flaky fine particles were added in an amount of 0.70% by mass with respect to the total mass of TEOS and MTES. % And stirred for 2 hours to obtain an inorganic glass solution B.
(2) Coating step In the same manner as in Example 1, coating was performed on a quartz glass plate washed using the inorganic glass solution B as a base material to obtain a coating film having a thickness of 10 μm.
(3) Drying Step The coating film obtained in the above step was dried at room temperature, and further dried at 40 ° C. for 20 minutes and at 80 ° C. for 10 minutes.
(4) Curing step The coating film obtained in the drying step is held at 300 ° C. for 1 hour using an oven under a nitrogen atmosphere, and a glass composite comprising a glass composite and a substrate (quartz glass plate). A laminate was obtained. The film thickness of the glass composite after curing was 2 μm.
(5) Evaluation of transparent screen When the laminate of the produced glass composite was used as it was as a transparent screen, the haze value was 17.7%, the diffuse transmittance was 13.2%, and the total light transmittance was It was 74.7%, the image clarity was 86%, the scratch hardness was 7H, and it had sufficient transparency and high scratch resistance.
The transmission front light intensity (× 1000) measured with a goniophotometer was 3.57, and it was found that the transmission front light intensity (× 1000) was excellent. The reflected front luminous intensity measured with a goniophotometer was 32.7, indicating that the reflected front luminous intensity was excellent. The viewing angle measured with a goniophotometer was ± 28 degrees, and it was found that the viewing angle characteristics were excellent. Moreover, as a result of visually evaluating the visibility, it was possible to visually recognize the image clearly. Further, the surface formed with the glass composite was difficult to attach fingerprints and could be easily wiped even if the fingerprints were attached. Furthermore, when the screen performance was evaluated, it was possible to visually recognize a clear image during both the front observation and the rear observation, and in particular, it was possible to visually recognize a very clear image during the front observation.

[Example 3]
(1) Inorganic glass solution preparation process About spherical fine particles for lead borosilicate glass frit (low softening point glass composed of 78% by mass of PbO, 10% by mass of SO ₂ , and 12% by mass of Ba ₂ O ₃ ) Zirconium oxide (manufactured by Kanto Denka Kogyo Co., Ltd., primary particle median diameter 10 nm, refractive index 2.40) 0.15% by mass and pine oil 10% by mass was added and kneaded to prepare a paste. Isopropyl alcohol was mixed so that the concentration of lead borosilicate glass frit in the paste was 20% by mass and dispersed with a dissolver to prepare inorganic glass solution C.
(2) Coating step The inorganic glass solution C was coated on a quartz glass plate washed as a substrate using a dip coating method to obtain a coating film having a thickness of 120 μm.
(3) Drying process The coating film was dried at 200 ° C. for 15 minutes to remove isopropyl alcohol.
(4) Curing step By sintering the coating film obtained in the drying step at 580 ° C for 20 minutes, a glass composite including a glass composite (glass composite) and a base material (quartz glass plate) is obtained. A laminate was produced. The thickness of the obtained glass composite was 100 μm.
(5) Evaluation of transparent screen When the laminate of the produced glass composite was used as it was as a transparent screen, the haze value was 10.2%, the diffuse transmittance was 9.0%, and the total light transmittance was It was 88.7%, the image clarity was 92%, the scratch hardness was 7H, and it had high transparency and scratch resistance.
The transmission front light intensity (× 1000) measured with a goniophotometer was 2.66, and it was found that the transmission front light intensity was excellent. The reflected front light intensity measured with a goniophotometer was 1.2, and it was found that the reflected front light intensity was excellent. The viewing angle measured with a goniophotometer was ± 22 degrees, and it was found that the viewing angle characteristics were excellent. Further, the surface formed with the glass composite was difficult to attach fingerprints and could be easily wiped even if the fingerprints were attached. Furthermore, when the screen performance was evaluated, it was possible to visually recognize a clear image during both the front observation and the rear observation, and in particular, it was possible to visually recognize a very clear image during the rear observation.

[Example 4]
In Example 1 (1) Inorganic glass solution preparation step, instead of the flaky aluminum fine particles A, titanium oxide (TiO ₂ ) -coated mica (Topy Industries, Ltd., trade name: Helios R10S, average diameter of primary particles 12 μm) A glass composite (thickness 20 μm) and a substrate (quartz glass plate) are provided in the same manner as in Example 1 except that 0.03% by mass is used with an aspect ratio of 80 and a regular reflectance of 16.5%. A laminate of glass composites was prepared.
When the laminate of the produced glass composite was used for a transparent screen as it was, the haze value was 3.2%, the diffuse transmittance was 3.0%, and the total light transmittance was 92.3%. The image clarity was 90%, the scratch hardness was 6H, and it had high transparency and scratch resistance.
The transmission front light intensity (× 1000) measured with a goniophotometer was 0.56, and it was found that the transmission front light intensity was excellent. The reflected front light intensity measured with a goniophotometer was 5.5, and it was found that the reflected front light intensity was excellent. The viewing angle measured with a goniophotometer was ± 12 degrees, and it was found that the viewing angle characteristics were excellent. Further, the surface formed with the glass composite was difficult to attach fingerprints and could be easily wiped even if the fingerprints were attached. Furthermore, when the screen performance was evaluated, a clear image could be visually recognized during the front observation, but the contour and hue of the image were slightly blurred during the rear observation.

[Example 5]
In Example 1 (1) Inorganic glass material solution preparation step, instead of flaky aluminum fine particles A, flaky aluminum fine particles B (average primary particle diameter 10 μm, aspect ratio 300, regular reflectance 62.8%) were used. A glass comprising a glass composite (thickness 20 μm) and a base material (quartz glass plate) in the same manner as in Example 1 except that 0.03% by mass and further 0.6% by mass of zirconium oxide as substantially spherical fine particles were added. A composite laminate was prepared.
When the laminated body of the produced glass composite was used for a transparent screen as it was, the haze value was 12.1%, the diffuse transmittance was 10.7%, and the total light transmittance was 88.5%. The image clarity was 85%, the scratch hardness was 6H, and it had high transparency and scratch resistance.
The transmission front luminous intensity (× 1000) measured with a goniophotometer was 13.62, and it was found that the transmission front luminous intensity was excellent. The reflected front light intensity measured with a goniophotometer was 3.5, and it was found that the reflected front light intensity was excellent. The viewing angle measured with a goniophotometer was ± 26 degrees, and it was found that the viewing angle characteristics were excellent. Further, the surface formed with the glass composite was difficult to attach fingerprints and could be easily wiped even if the fingerprints were attached. Furthermore, when the screen performance was evaluated, it was possible to visually recognize a very clear image during both the front observation and the rear observation.

[Example 6]
In Example 3 (1) Inorganic glass solution preparation step, instead of zirconium oxide, titanium oxide (manufactured by Teika Co., Ltd., trade name: MT-01, refractive index 2.72, median diameter of primary particles 10 nm) 0 A glass composite laminate comprising a glass composite (thickness 5000 μm) and a substrate (quartz glass plate) was prepared in the same manner as in Example 3 except that 0.003 mass% was added and the coating process was repeated 50 times. did.
When the laminate of the produced glass composite was used as it was as a transparent screen, the haze value was 9.1%, the diffuse transmittance was 7.7%, and the total light transmittance was 84.2%. The image clarity was 88%, the scratch hardness was 7H, and it had high transparency and scratch resistance.
The transmission front luminous intensity (× 1000) measured with a goniophotometer was 3.12, and it was found that the transmission front luminous intensity was excellent. The reflected front light intensity measured with a goniophotometer was 2.3, and it was found that the reflected front light intensity was excellent. The viewing angle measured with a goniophotometer was ± 24 degrees, and it was found that the viewing angle characteristics were excellent. Further, the surface formed with the glass composite was difficult to attach fingerprints and could be easily wiped even if the fingerprints were attached. Furthermore, when the screen performance was evaluated, it was possible to visually recognize a clear image during both the front observation and the rear observation, and in particular, it was possible to visually recognize a very clear image during the rear observation.

[Example 7]
In Example 1 (1) Inorganic glass material solution preparation step, instead of the flaky aluminum fine particles A, silver fine particles (average diameter of primary particles 1 μm, aspect ratio 200, regular reflectance 32.8%) were changed to 0.85. A laminated body of a glass composite comprising a glass composite (thickness 20 μm) and a base material (quartz glass plate) was produced in the same manner as in Example 1 except that mass% was added.
When the laminate of the produced glass composite was used for a transparent screen as it was, the haze value was 5.4%, the diffuse transmittance was 3.8%, and the total light transmittance was 70.1%. The image clarity was 75%, the scratch hardness was 6H, and it had high transparency and scratch resistance.
The transmission front light intensity (× 1000) measured with a goniophotometer was 1.32, and it was found that the transmission front light intensity was excellent. The reflected front luminous intensity measured with a goniophotometer was 13.8, and it was found that the reflected front luminous intensity was excellent. The viewing angle measured with a goniophotometer was ± 15 degrees, and it was found that the viewing angle characteristics were excellent. Further, the surface formed with the glass composite was difficult to attach fingerprints and could be easily wiped even if the fingerprints were attached. Furthermore, when the screen performance was evaluated, it was possible to visually recognize a clear image during both the front observation and the rear observation, and in particular, it was possible to visually recognize a very clear image during the front observation.

[Example 8]
Example 3 (1) In the inorganic glass solution preparation step, zirconium oxide was not added, and flaky aluminum fine particles A were added as brilliant flaky fine particles in the same manner as in Example 3, A laminated body of glass composites comprising a glass composite (thickness 80 μm) and a substrate (quartz glass plate) was produced.
When the laminate of the produced glass composite was used as it was as a transparent screen, the haze value was 2.0%, the diffuse transmittance was 1.8%, and the total light transmittance was 90.1%. The image clarity was 84%, the scratch hardness was 7H, and it had high transparency and scratch resistance.
The transmission front luminous intensity (× 1000) measured with a goniophotometer was 0.81, and it was found that the transmission front luminous intensity was excellent. The reflected front light intensity measured with a goniophotometer was 5.2, and it was found that the reflected front light intensity was excellent. The viewing angle measured with a goniophotometer was ± 15 degrees, and it was found that the viewing angle characteristics were excellent. Further, the surface formed with the glass composite was difficult to attach fingerprints and could be easily wiped even if the fingerprints were attached. Furthermore, when the screen performance was evaluated, it was possible to visually recognize a clear image during both the front observation and the rear observation, and in particular, it was possible to visually recognize a very clear image during the front observation.

[Comparative Example 1]
Example 1 (1) Instead of the water glass aqueous solution used in the inorganic glass solution manufacturing process, an acrylic solution (Mitsubishi Rayon Co., Ltd., trade name: Acrypet VH was dissolved in toluene to 20 mass%. In this case, 0.60% by mass of zirconium oxide was added to the acrylic resin instead of the flaky aluminum fine particles A, and the mixture was stirred at 23 ° C. and 45% humidity for 5 hours to obtain a fine particle dispersed acrylic solution.
(2) Coating step In the same manner as in Example 1, the fine particle-dispersed acrylic solution was coated on a quartz glass plate washed as a substrate to obtain a coating film having a thickness of 12 μm.
(3) Drying step The coating film obtained in the above step was dried at room temperature, and further dried at 40 ° C. for 20 minutes, 80 ° C. for 1 hour, and reduced pressure for 12 hours. The film thickness of the fine particle-dispersed acrylic layer after drying was 3 μm.
(4) Evaluation of transparent screen When the laminate of the prepared fine particle-dispersed acrylic layer and the quartz glass substrate was used as it was as a transparent screen, the haze value was 12.2% and the diffuse transmittance was 10.3%. The total light transmittance was 84.8%, the image clarity was 84%, the scratch hardness was 3B, and although it was transparent, the scratch resistance was poor. Further, the transmission front light intensity (× 1000) measured with a goniophotometer was 2.54, the reflection front light intensity was 1.1, and the viewing angle was ± 20 degrees. Also, the surface on which the fine particle-dispersed acrylic layer is formed is easily attached with fingerprints, and the attached fingerprints cannot be easily wiped off. Furthermore, when the screen performance was evaluated, it was possible to visually recognize a clear image during both the front observation and the rear observation, and in particular, it was possible to visually recognize a very clear image during the rear observation.

[Comparative Example 2]
In Comparative Example 1, a fine particle-dispersed acrylic layer was prepared in the same manner as Comparative Example 1 except that 0.03% by mass of aluminum fine particles A was added to the acrylic resin pellets instead of zirconium oxide. When the laminate of the prepared fine particle-dispersed acrylic layer and the quartz glass substrate was used as a transparent screen as it was, the haze value was 4.7%, the diffuse transmittance was 4.1%, the total light transmittance was 88.1%, The image clarity was 88%, the scratch hardness was 3B, and although it was transparent, the scratch resistance was poor. Further, the transmission front light intensity (× 1000) measured with a goniophotometer was 1.02, the reflection front light intensity was 9.6, and the viewing angle was ± 16 degrees. Also, the surface on which the fine particle-dispersed acrylic layer is formed is easily attached with fingerprints, and the attached fingerprints cannot be easily wiped off. Furthermore, when the screen performance was evaluated, it was possible to visually recognize a clear image during both the front observation and the rear observation, and in particular, it was possible to visually recognize a very clear image during the front observation.

[Comparative Example 3]
In Comparative Example 1, mica particles (product name: A-21S, trade name: A-21S, manufactured by Yamaguchi Mica Co., Ltd.) as a flaky fine particle having no glitter, instead of zirconium oxide, positive aspect ratio 70, positive A fine particle-dispersed acrylic layer was prepared in the same manner as in Comparative Example 1 except that 0.20% by mass of the reflectance (9.8%) was added to the acrylic resin pellets. When the produced laminate of the fine particle-dispersed acrylic layer and the quartz glass substrate was used as it was as a transparent screen, the haze value was 0.5%, the diffuse transmittance was 0.4%, the total light transmittance was 88.3%, The image clarity was 70%, the scratch hardness was 3B, and although it was transparent, the scratch resistance was poor. Further, the transmission front luminous intensity (× 1000) measured with a goniophotometer is 0.00, the reflection front luminous intensity is 0.0, the viewing angle is ± 6 degrees, the transmission front luminous intensity, reflection Both front brightness and viewing angle were inferior. It was. Also, the surface on which the fine particle-dispersed acrylic layer is formed is easily attached with fingerprints, and the attached fingerprints cannot be easily wiped off. Further, when the screen performance was evaluated, the outline of the image was blurred during front observation, which was unsuitable for use as a screen, and the outline and hue of the image were slightly blurred during rear observation.

  Table 3 shows details of the glass composites or fine particle-dispersed acrylic layers used in Examples and Comparative Examples.

Table 4 shows the results of various physical properties and performance evaluation of the transparent screen (laminated body of glass composite or laminated body of fine particle-dispersed acrylic layer) used in Examples and Comparative Examples.

DESCRIPTION OF SYMBOLS 10 Inorganic glass 11 Glossy flaky fine particle 12 Substantially spherical fine particle 13 Glass composite 14 Base material 15, 21 Laminate of glass composite 16, 17, 26A, 26B Projected light 18, 27A, 27B Scattered light 19, 24 Viewer 22 Transparent partition (support)
23 Transparent screen 25A, 25B Projection device

Claims (18)

  A glass composite for transparent screen, comprising inorganic glass and at least one of glittering flaky fine particles or substantially spherical fine particles.   The glass composite according to claim 1, wherein an average diameter of primary particles of the glittering flaky fine particles is 0.01 to 100 μm.   The glass composite according to claim 1 or 2, wherein the specular reflectance of the glittering flaky fine particles is 12% or more.   The glass composite according to any one of claims 1 to 3, wherein an average aspect ratio of the glittering flaky fine particles is 3 to 800.   The bright flaky fine particles are selected from the group consisting of aluminum, silver, copper, platinum, gold, titanium, nickel, tin, tin-cobalt alloy, indium, chromium, titanium oxide, aluminum oxide, and zinc sulfide. It is the glittering material which coat | covered the metal or metal oxide to the system particle | grains, glass, or the glittering material which coat | covered the metal or metal oxide to natural mica or synthetic mica. Glass composite.   The glass composite according to any one of claims 1 to 5, wherein the inorganic glass is at least one selected from the group consisting of water glass, a sol-gel material, and a glass material having a softening temperature of 150 to 650 ° C. body.   The glass composite according to any one of claims 1 to 6, wherein a content of the glittering flaky fine particles is 0.0001 to 5.0 mass% with respect to the inorganic glass. The difference between the refractive index n ₂ of the substantially spherical fine particles and the refractive index n ₁ of the inorganic glass is the following mathematical formula (1):
| N ₁ −n ₂ | ≧ 0.1 (1)
The glass composite as described in any one of Claims 1-7 which satisfy | fills.   The substantially spherical fine particles are at least one selected from the group consisting of zirconium oxide, zinc oxide, titanium oxide, cerium oxide, barium titanate, and strontium titanate, according to any one of claims 1 to 8. The glass composite as described.   The glass composite according to any one of claims 1 to 9, wherein a median diameter of primary particles of the substantially spherical fine particles is 0.1 to 100 nm.   The glass composite according to any one of claims 1 to 10, wherein a content of the substantially spherical fine particles is 0.0001 to 2.0 mass% with respect to the inorganic glass.   The glass composite according to any one of claims 1 to 11, which is used for a transmissive transparent screen or a reflective transparent screen.   The laminated body of the glass composite provided with the glass composite as described in any one of Claims 1-12, and a base material.   A transmissive transparent screen comprising the glass composite according to claim 1 or a laminate of the glass composite according to claim 13.   A reflective transparent screen comprising the glass composite according to claim 1 or a laminate of the glass composite according to claim 13.   The glass composite according to any one of claims 1 to 12, the laminate of the glass composite according to claim 13, the transmissive transparent screen according to claim 14, or the reflective type according to claim 15. A vehicle member provided with a transparent screen.   The glass composite according to any one of claims 1 to 12, the laminate of the glass composite according to claim 13, the transmissive transparent screen according to claim 14, or the reflective type according to claim 15. Building member with a transparent screen.   The glass composite according to any one of claims 1 to 12, the laminate of the glass composite according to claim 13, the transmissive transparent screen according to claim 14, or the reflective type according to claim 15. An image projection system comprising a transparent screen and a projection device.