JP2019113657A - Composition for light scattering body formation, light scattering body, sheet-like laminate, projection screen, and image display system - Google Patents

Abstract

To achieve both transparency and clearness of a projection image on a projection screen at high level.SOLUTION: A light scattering body 10 contains a resin medium 3 containing a resin, a first particle 1 which is dispersed in the resin medium 3 and has a median diameter of 50 nm or more and 360 nm or less, and a second particle 2 which is dispersed in the resin medium, has a median diameter of 500 nm or more and 1.5 μm or less, and has a diamond structure, in which the total content of the first particle and the second particle is 0.01 pts.mass or more and 20.0 pts.mass or less based on 100 pts.mass of the resin medium, a particle number ratio M/Mof a particle number Mof the first particles to a particle number Mof the second particles is 100 or more and 5,000 or less, and the total light transmittance of the light scattering body is 80% or more.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a composition for forming a light scatterer, a light scatterer, a sheet-like laminate, a projection screen, and an image display system.

  A light transmissive transparent screen is known as a projection screen, and a transparent screen for reflective (reflection mode) projection or a transparent screen for transmissive (transmission mode) projection is used. Conventionally, as a light scatterer, a transparent screen is formed by forming a minute lens structure such as an optical lens light scattering plate on a film, or transparent light such as high refractive index fine particles or low refractive index airgel inside the film. Scatterers have been used to scatter light while maintaining some degree of transparency. Furthermore, light scatterers have also been developed, such as a laminated glass type in which a hologram sheet is enclosed between two sheets of glass, and a panel type in which high refractive index fine particles are mixed into a transparent substrate.

  In recent years, there has been a growing demand to project and display digital image information, advertisements, etc. in LED lighting, digital signage used in indoor and outdoor advertising, store show windows, home theaters, posters, large image projection at events, etc. . In addition, it is said that the demand for a transparent screen used for a head-up display, a wearable display, etc. which projects navigation, position information, etc. on the windshield of a car is increasing more and more. The light scatterers applied to these applications are required to have a sufficiently sharp projected image while having transparency which does not impair the visibility of the background. However, when the total light transmittance of the light scatterer is increased, the sharpness of the projected image tends to be lowered, and it is difficult to achieve both transparency and sharpness of the projected image.

  Various studies have been made on the technology relating to light scatterers or transparent screens. For example, in the following Patent Document 1, for the purpose of obtaining high light transmittance and high light scattering, a transparent material having a refractive index of 0.01 to 0.1 smaller than that of a resin and an average particle diameter of 1 to 10 μm A light scattering synthetic resin in which a powder is dispersed has been proposed. Moreover, in the following patent document 2, the median diameter 0.01 included in the substrate, the transparent thin film layer provided on the substrate, and the transparent thin film layer for the purpose of coexistence of high transmission visibility and good scattering reflectivity. Proposed is a transmission screen characterized in that the light scattering body is a diamond fine particle obtained by oxidizing a nanodiamond having a graphite phase obtained by the radiation method, which is made of a light scattering body of 1 μm to 1 μm. ing.

  Furthermore, there is also a case where a condensing lens is mounted on a transmission screen to improve the sharpness of an image (for example, see Patent Document 3 below). Further, in Patent Document 4 listed below, in order to obtain reflection and transmission characteristics suitable for screen applications, a high refractive index film containing a low refractive index optical film made of a fluorocarbon resin, fine particles of a metal oxide, and a specific dispersant An optical multilayer film is proposed in which a coating type optical laminated film composed of a refractive index optical film is laminated, and a reflective screen including such an optical multilayer film is also disclosed.

Japanese Examined Patent Publication No. 60-021661 JP, 2011-113068, A JP 2007-240686 A JP 2005-99675 A

  The screen using the light-scattering synthetic resin described in Patent Document 1 has a technical problem that the light transmittance is low and the transparency is not sufficient. The transmissive screen described in Patent Document 2 has a technical problem that the brightness of the projected image is reduced when the total light transmittance is increased, and it is difficult to achieve both at a high level. The transmissive screen described in Patent Document 3 has a technical problem that the transparency is significantly impaired due to the mounting of the condenser lens. The reflective screen described in Patent Document 4 has a technical problem that light is reflected at the interface of each layer to reduce the transparency.

  The present invention has been made in view of the above technical problems, and can form a light scatterer capable of achieving a high level of compatibility between the transparency in a projection screen and the sharpness of a projected image, and the same. It is an object of the present invention to provide a composition for forming a light scatterer, and a projection screen capable of achieving both high transparency and transparency of a projected image, and an image display system including the same.

  As a result of intensive studies to achieve the above object, the present inventors found that in a resin having high light transmittance, two types of specific particles having a specific refractive index difference with respect to the resin, in a specific ratio. It has been found that the dispersed light scatterers can enhance the sharpness of the projected image while sufficiently maintaining the high light transmittance of the resin, and the present invention has been completed.

The present invention contains a resin, a first particle having a median diameter of 50 nm to 360 nm, and a second particle having a median diameter of 500 nm to 1.5 μm and having a diamond structure, The total content of the particles and the second particles is 0.01 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the resin, and the number M ₁ of the _first particles and the second particles The particle number ratio M ₁ / M ₂ to the number M ₂ of particles of the resin is 100 or more and 5000 or less, and the resin provides a composition for forming a light scatterer having a total light transmittance of 80% or more at a thickness of 20 μm. Do.

  According to the composition for forming a light scatterer of the present invention, it is possible to form a light scatterer capable of achieving both the transparency of a projection screen and the sharpness of a projected image at a high level.

  The present inventors consider as follows the reason why the above-mentioned effect is exhibited by the composition for forming a light scatterer of the present invention. First, a composition having a high total light transmittance becomes a medium by applying and curing the composition on a substrate, and a light scatterer in which the first particles and the second particles are dispersed in the resin medium. Can be formed. Then, in this light scatterer, (1) Rayleigh scattering can be generated by the first particle which is a particle smaller than the visible light wavelength, and (2) the second particle which is a particle larger than the visible light wavelength Scattering can be generated, and (3) the total content of the first particle and the second particle and the particle number ratio are set in a specific range, whereby light of incident light can be generated. Locally strong Mie scattering is obtained by a small amount of the second particle while reducing the loss, and this Mie scattered light is isotropically multiply scattered by a large amount of the first particle existing in the periphery thereof The inventors believe that the transparency and the sharpness of the projected image can be compatible at a high level.

  Note that Rayleigh scattering is light scattering by particles smaller than the light wavelength (about 1/10 of the light wavelength), and the scattering intensity is inversely proportional to the fourth power of the light wavelength, and Mie scattering Is the scattering phenomenon of light by particles larger than the wavelength of light, the scattering intensity is not largely dependent on the wavelength, and the Tyndall phenomenon when multiple particles are irregularly scattered occurs by Mie scattering, Etc. are known. However, when it is attempted to form an image on a transparent scatterer using light scattering mainly based on Rayleigh scattering, the light transmittance becomes high, but the sharpness of the image is poor and the scattered light depends on the wavelength Because of this, a blue shift of the image also takes place. On the other hand, when Mie scattering is the main component, the intensity of the scattered light is increased, but the light transmittance is reduced, and sufficient transparency can not be obtained. Therefore, for example, when particles having a high refractive index such as diamond are used for light scattering particles and the median diameter of the particles is 150 nm to 300 nm which is less than the lower limit of visible light wavelength, the transparency of the transparent light scatterer There is a limit to the compatibility with the image clarity. The present invention is based on the study of the present inventors focusing on the above-described problem of the prior art.

In the light scattering body composition of the present invention, the refractive index of the resin n _A, the refractive index n _B of the first _particles, and the refractive index n _C of the second particles is represented by the following formula (1) It is preferable to satisfy the condition.
0.15 <| n _B −n _A | ≦ n _C −n _A <1.15 (1)

  In the composition for forming a light scatterer according to the present invention, it is preferable that the first particles and the second particles are diamond, and the carbon concentration is 90% by mass or more.

The present invention also relates to a resin medium containing a resin, first particles dispersed in the resin medium, having a median diameter of 50 nm or more and 360 nm or less, and a resin medium dispersed in the resin medium, having a median diameter of 500 nm or more And a second particle having a diamond structure and not exceeding 1.5 μm, wherein the total content of the first particle and the second particle is 100 parts by mass of the resin medium. not more than 20.0 parts by mass or more 0.01 part by mass, the particle number ratio _M 1 / _{M 2} of the number of particles of the first particle _{M 1} and particle number _{M 2} of the second particles is more than 100 5000 The following provides the light scatterer in which the total light transmittance of the light scatterer is 80% or more.

  According to the light scatterer of the present invention, the transparency in the projection screen and the sharpness of the projected image can be compatible at a high level.

Satisfy the light scatterer of the present invention, the refractive index of the resin medium n _A, the refractive index of the first particles n _B, and the refractive index n _C of the second particles, represented by the following formula (1) Is preferred.
0.15 <| n _B −n _A | ≦ n _C −n _A <1.15 (1)

  In the light scatterer of the present invention, it is preferable that the first particle and the second particle be diamond, and the carbon concentration be 90 mass% or more.

  The present invention also provides a sheet-like laminate comprising a substrate, and a light scattering layer comprising the light scattering body according to the present invention provided on the substrate.

  According to the sheet-like laminate of the present invention, by providing the light scattering layer comprising the light scattering body according to the present invention, it is possible to realize a projection screen having high transparency and high sharpness of the projected image at a high level. Become. In addition, the sheet-like laminate of the present invention can maintain flatness of the projection surface by providing a heavy material at the lower part (for example, applying a force of 1 kg weight to 500 kg weight). It is easy to eliminate distortion.

  The sheet-like laminate of the present invention may further include a resin layer having a hardness of 2H or more on at least one outermost surface. Such a sheet-like laminate can be used for writing with a marker pen or the like and erasing with a dedicated sponge eraser or the like.

  In the sheet-like laminate of the present invention, the base material may have a curved surface.

  The present invention also provides a projection screen comprising the sheet-like laminate according to the present invention. The projection screen of the present invention can achieve both transparency and sharpness of the projected image at a high level. Moreover, according to the projection screen of the present invention, sufficient sharpness can be obtained in any of the transmission image and the reflection image. That is, the projection screen of the present invention may be a transmissive transparent screen or a reflective transparent screen. Also, the projection screen of the present invention can simultaneously project the transmission image and the reflection image.

  The projection screen of the present invention may further include storage means capable of storing the sheet-like laminate in a roll shape.

  In the projection screen of the present invention, two sheet-like laminates according to the present invention are low refractive index media in which the light scattering layers are opposed to each other and the refractive index is smaller between the light scattering layers. It may have a structure arranged in the state where it intervenes. Such projection screens can reduce spatial coherent image noise.

  The present invention also provides an image display system comprising an image projection means for projecting an image, the light scatterer according to the present invention, the sheet-like laminate according to the present invention or the projection screen according to the present invention.

  According to the image display system of the present invention, for example, a transparent member, a sheet-like laminate or a projection screen provided with a light scatterer between an object or affected part and a worker during work such as processing or surgery By installing, when a worker observes a subject or a diseased part, it is possible to display and provide information based on characters and images from the outside on the background image of the subject or the diseased part to the worker.

  The image display system of the present invention detects the approach of a person or an object, and when it is determined that the person or the object approaches based on the information from the detection means, an image is displayed on the light scatterer or the projection screen from the image projection means. And means for projecting According to such a system, it is possible to provide information or display an alert when a person or an object approaches.

  According to the present invention, a light scatterer capable of achieving a high level of compatibility between the transparency in a projection screen and the sharpness of a projected image, a composition for forming a light scatterer capable of forming the same, and transparency It is possible to provide a projection screen capable of achieving a high level of compatibility with the sharpness of the projection image and the image display system including the projection screen.

It is a schematic cross section which shows one Embodiment of the light-scattering body of this invention. It is a schematic cross section which shows one Embodiment of the sheet-like laminated body of this invention. It is a schematic cross section which shows one Embodiment of the projection screen of this invention. It is a schematic cross section which shows one Embodiment of the image display system of this invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

[Light scatterer]
The light scattering medium of the present embodiment is a resin medium (hereinafter, the resin constituting the resin medium may be referred to as component (A)) and is dispersed in the resin medium, and the median diameter is 50 nm or more and 360 nm or less A first particle (hereinafter sometimes referred to as component (B)) and a second particle having a diamond structure and a median diameter of 500 nm to 1.5 μm dispersed in a resin medium And (C) component).

  In the present specification, the median diameter refers to the 50% median diameter based on the volume of particles, and is measured using a dynamic scattering type particle size distribution analyzer (for example, LA-960 manufactured by Horiba, Ltd.).

  FIG. 1 is a schematic cross-sectional view showing the light scatterer of the present embodiment. The light scatterer 10 shown in FIG. 1 contains a resin medium 3 and first particles 1 and second particles 2 dispersed in the resin medium 3.

  The resin medium may be formed from a resin composition containing a resin.

  Examples of the resin include thermoplastic resins and thermosetting resins. Specifically, acrylic resins, acrylic urethane resins, polyester acrylate resins, polyurethane acrylate resins, polyester resins, polyolefin resins, urethane resins, polycarbonate resins, cellulose resins Thermoplastic resins such as acetal resin, vinyl resin, polystyrene resin, polyamide resin, polyarylate resin, polyvinyl alcohol resin, polyvinyl chloride resin, polysulfone resin, fluorine resin; epoxy acrylate resin, epoxy resin, polyimide resin, melamine resin, Thermosetting resins such as phenol resin and silicone resin can be mentioned. These resins may be used alone or in combination of two or more.

  The resin medium preferably contains a thermoplastic resin from the viewpoint of moldability.

  The composition for a resin is preferably a water dispersion system from the viewpoint of dispersibility. In that case, an acrylic resin, a polyester resin, a urethane resin, a fluorine resin, a silicone resin etc. can be contained as resin.

  The refractive index of the resin medium is preferably 1.28 or more and 1.80 or less, and more preferably 1.30 or more and 1.60 or less from the viewpoint of light scattering efficiency. Refractive index as used herein refers to the measured value at a wavelength of 589.3 nm of a sodium lamp.

  The total light transmittance at a thickness of 20 μm of the resin medium is preferably 80% or more, and more preferably 85% or more, from the viewpoint of transparency when producing a transparent screen. Also, the total light transmittance of the resin medium may be 99% or less from the viewpoint of physical limitations of the material.

  The first particle is set to a median diameter of 50 nm or more, which is the upper limit of Rayleigh scattering, and 360 nm or less, which is the lower limit of the visible light wavelength range defined in JIS Z8120. The first particles are more preferably 70 nm or more and 300 nm or less from the viewpoint of visibility.

The material of the first particle is not particularly limited, but specifically, diamond; zirconium oxide, titanium oxide, barium titanate, strontium titanate, aluminum oxide, zinc oxide, copper oxide, oxide Metal oxides such as cesium, chromium oxide, niobium oxide, cerium oxide, indium tin oxide and tantalum oxide; metals such as aluminum, nickel, cobalt, iron, titanium, chromium, zinc, tungsten, mercury, platinum and molybdenum; polycarbonate resin Polyurethane resin, polyacrylic resin, polystyrene resin, polyvinyl alcohol resin, polyolefin resin, polyvinyl olefin resin, polyester resin, polyether resin, fluorine resin, polysulfone resin, polyether ether ketone resin, polyamide resin, PO resin Imide resins, melamine resins, phenol resins, epoxy resins, silicone resins, and the like resins such as cellulose resins. Among these, from the viewpoint of visibility, the refractive index of the resin is n _A , the first particle is n _B , and the second particle is n _C , 0.15 <| n _B −n _A | ≦ Those satisfying the relationship of n _C −n _A <1.15 are preferable, and diamond, metal oxide and metal having a refractive index of 1.8 or more are more preferable, and from the viewpoint of being able to widen the viewing angle, diamond Is more preferred.

  Although various kinds of diamonds exist depending on the production method and the purification method, any of them can be used. For example, synthetic diamonds such as high pressure synthetic diamonds, detonation synthetic diamonds, and vapor grown diamonds, and natural diamonds can be mentioned. High-pressure synthetic diamond is a method of synthesizing diamond by externally applying ultra-high pressure to carbon. Detonation synthetic diamond is a method of synthesizing a diamond by detonating an explosive such as TNT or hexogen in a closed steel chamber.

  Further, diamond is classified into three types of crystal structural forms, single crystal diamond, polycrystalline diamond, and composite diamond as a composite, but any of them can be used. The first particles are preferably single crystal diamond from the viewpoint of total light transmittance.

  The polycrystalline diamond may be synthesized using graphite as a raw material. In addition, with regard to the symmetrical structure of diamond crystals, although single crystal diamond has a cubic system diamond structure, some polycrystalline diamonds have hexagonal crystal structure with cubic system diamond structure as a crystal symmetry. There is a mixture of light (Lonsdaleite) structures. Polycrystalline diamond having a Rondezlite structure has a Vickers hardness higher than that of a cubic diamond structure, and has the same refractive index but high optical scattering efficiency due to the internal structure of the crystal. In composite diamond, polycrystalline diamond, graphite and DLC (Diamond like carbon) are compositely formed on the surface of single crystal diamond. Any of these may be used.

  Detonation synthetic diamond has a thin graphite layer on the surface of both single crystal diamond and polycrystalline diamond, and further has chemical functions such as hydroxyl group, amino group and carboxyl group in its graphite phase, so It has high dispersibility. Some natural diamonds have high dispersibility in liquid.

  The first particle is preferably a particle having a diamond structure having a carbon concentration of 90% by mass or more. Such particles are preferably low in metal impurities.

  Examples of atoms that can be covalently bonded include diamond (C), silicon (Si), and germanium (Ge) of group IV elements. These have four outermost shell electrons (valence electrons), and have a tetrahedrally bonded structure with the nearest atomic number (coordination number) 4 and the second adjacent atomic number (total number of next adjacent atoms) 12 It can be taken. Such a structure is called a diamond structure, and particles containing this diamond structure are called "particles having a diamond structure".

In the present specification, the carbon concentration of particles is to measure the weight change (ΔM) before and after combustion by thermogravimetric analysis assuming that the concentration of oxygen and nitrogen contained in the particles is 0.5% by mass or less. Calculated by That is, in (thermogravimetric analysis), (total particle weight)-(residual ash weight) is regarded as the carbon content, and the carbon concentration is calculated from the following formula.
Carbon concentration (%) = [(total weight of particles) − (weight of residual ash) / (total weight of particles)] × 100

  The first particle is more preferably a particle having a carbon concentration derived from a diamond structure of 90% by mass or more. Such particles are preferred because they have a low graphite concentration which exhibits a black color. The carbon concentration derived from the diamond structure can be measured using XRD.

  The second particles are set to a median diameter of 500 nm or more and 1.5 μm or less. Thereby, Mie scattering of visible light can be effectively generated. The second particles are more preferably 550 nm or more and 1.0 μm or less from the viewpoint of visibility.

  The second particles are preferably particles having a diamond structure having a carbon concentration of 90% by mass or more. Such particles are preferably low in metal impurities.

  The second particles are more preferably particles having a carbon concentration derived from a diamond structure of 90% by mass or more. Such particles are preferred because they have a low graphite concentration which exhibits a black color.

  In the light scatterer of the present embodiment, the total content of the first particles and the second particles is 0.01 with respect to 100 parts by mass of the resin medium from the viewpoint of improving the brightness of the projected image and the transparency of the screen. It is preferable that it is mass part or more and 20.0 mass parts or less, and it is more preferable that it is 2 mass parts or more and 15.0 mass parts or less.

It first particle number ratio _M 1 / _{M 2} of the number of particles of particles _{M 1} and particle number _{M 2} of the second particles is preferably 100 to 5000, it is 200 to 3,000 Is more preferred. M ₁ / M ₂ can also be calculated by volume density conversion.
Assuming that the first particle and the second particle are round spheres, the true specific gravity _{1 1} [g · cm ⁻³ ] of the first particle, the median diameter r ₁ [μm], the blending amount of the light scatterer Assuming that C ₁ [g], the true specific gravity _{2 2} [g · cm ⁻³ ] of the second particle, the median diameter r ₂ [μm], and the compounding amount C ₂ [g] of the light scatterer, The particle number of the particles (M ₁ ) and the particle number of the second particles (M ₂ ) are respectively
_{M 1 = [3/4 ×} 10 12 × C 1] ÷ [ρ 1 × π × (r 1/2) 3], and _{M 2 = [3/4 ×} 10 12 × C 2] ÷ [ρ 2 × ^{_{π × (r 2/2)}} 3]
The particle number ratio M ₁ / M ₂ is
M ₁ / M ₂ = (C ₁ × ρ ₂ × r ₂ ³ ) / (C ₂ × ρ ₁ × r ₁ ³ )
It can be obtained from

In the light scatterer of the present embodiment, the resin medium, the first particles and second particles, the refractive index of the resin medium n _A, the refractive index of the refractive index n _B, and the second particles of a first particle n _C is selected to satisfy the condition represented by the following formula (1).
0.15 <| n _B −n _A | ≦ n _C −n _A <1.15 (1)

  The conditions of the above-mentioned formula (1) can be satisfied by using particles having the above-mentioned resin component, diamond and diamond structure as the resin medium, the first particles and the second particles, respectively. In this case, the difference in refractive index between the resin medium and the first particles and the second particles is sufficiently obtained, and in the resin medium having a high light transmittance, light of the first particles and the second particles is used. Scattering efficiency can be increased.

  The light scatterer of the present embodiment is preferably in the form of a sheet, and the thickness thereof is preferably 1 to 50 μm, and more preferably 2 to 30 μm from the viewpoint of transparency. In addition, the thickness of a light-scattering body is measured using a micrometer (made by Mitutoyo, MDH-25M).

  The total light transmittance of the light scatterer of the present embodiment is preferably 75% or more, and more preferably 80% or more.

The light scatterer of the present embodiment preferably has a lightness L ^* value (measured at an arrangement of 20 ° incidence and 0 ° transmission) in CIE 1976 (L ^* , a ^* , b ^* ) color space of 0.5 or more. And 0.7 or more are more preferable.

  The light scattering body of the present embodiment includes, for example, a step of applying a composition for forming a light scattering body to be described later on a peeling substrate, and a step of forming a sheet-like light scattering body by drying or curing a coating film. And a method comprising

  The release substrate is not particularly limited as long as it is used as a normal release substrate, but high-quality paper, arc paper, mirror-coated paper, non-woven fabric, aluminum foil, gold foil, silver foil, polyester film, polyolefin film, polyvinyl acetate A film, a polystyrene film, a polyvinyl chloride film, a polyimide film etc. are mentioned. In addition, the surface of the release substrate may be subjected to surface treatment such as silicone processing, polyethylene lamination, clay coating, application of a release agent, or the like so that the light scattering body can be easily peeled off from the release substrate.

<Sheet-like laminate>
FIG. 2: is a schematic cross section which shows one Embodiment of a sheet-like laminated body. The sheet-like laminate 20 of the present embodiment shown in FIG. 2 includes a base 4 and a light scattering layer formed on the base 4 and made of the light scatterer 10 of the above-described present embodiment.

  When the sheet-like laminate is used as a reflective transparent screen, the substrate is not particularly limited as long as it does not inhibit the optical properties, but specifically, silicate glass, phosphate Glass, oxidized glass such as borate glass; silicate glass, alkali silicate glass, soda lime glass, potassium lime glass, lead glass, barium glass, silicate glass such as borosilicate glass; polyester based resin, polycarbonate based Plastics such as resin, polyolefin resin, polyacrylic resin, cellulose resin, polyvinyl resin; Quartz; metal such as aluminum oxide, titanium oxide, niobium oxide, tantalum oxide, indium tin oxide, zinc oxide, zirconium oxide, cerium oxide Oxide; steel, carbon steel, chromium-molybdenum steel, aluminum alloy, Alloys such as Tenless alloy, Copper alloy, Titanium alloy; Metals such as gold, silver, copper, zinc, iron, aluminum, platinum, lead, palladium, etc .; Plant fibers such as cotton, hemp; Silk, wool, alpaca, angora, cashmere Animal fibers such as mohair; synthetic fibers such as rayon, polyacetate, promix, nylon, polyester, polyacrylic, polyvinyl chloride, polyurethane etc .; inorganic fibers such as glass fibers, metal fibers, carbon fibers etc.

  When the sheet-like laminate is used as a transmission-type transparent screen, the substrate is not particularly limited as long as it does not inhibit the optical properties, but specifically, silicate glass, phosphate Glass, oxidized glass such as borate glass; silicate glass, alkali silicate glass, soda lime glass, potassium lime glass, lead glass, barium glass, silicate glass such as borosilicate glass; polyester based resin, polycarbonate based Plastics such as resin, polyolefin resin, polyacrylic resin, cellulose resin, polyvinyl resin, etc .; quartz; vegetable fibers such as cotton and hemp; silk, wool, animal fibers such as alpaca, angora, cashmere and mohair; rayon, Polyacetate, promix, nylon, polyester, polyacrylic, polyvinyl chloride, polyurea Synthetic fibers such as down, glass fibers, metal fibers, inorganic fibers such as carbon fibers.

  The thickness of the substrate is not particularly limited, but is preferably 10 μm to 50 mm, and more preferably 20 μm to 30 mm from the viewpoint of strength and economy.

  A light-scattering layer consists of a light-scattering body of this embodiment mentioned above, and can be formed using the composition for light-scattering body formation mentioned later.

  The thickness of the light scattering layer is preferably 1 to 50 μm, and more preferably 2 to 30 μm, from the viewpoint of the transparency of the sheet-like laminate. The thickness of the light scattering layer can be measured using a micrometer (Mittoyo MDH-25M).

  In the sheet-like laminate of the present embodiment, at least one of the outermost surfaces is provided with a known hard coat layer, a diffusion preventing layer, an antistatic layer, an anti-fingerprint film layer, or a matte layer to increase the strength of the film. Can.

  In addition, the sheet-like laminate of the present embodiment has at least one outermost surface (for example, the surface of the base opposite to the side on which the light scattering layer is provided, or the side opposite to the base of the light scattering layer On the surface of the), the hardness can further be provided with a resin layer of 2H or more. Such a sheet-like laminate enables writing with a marker pen or the like on the sheet-like laminate and erasing of writing with a dedicated sponge eraser etc. while viewing the background image and the projection image by the projector simultaneously. .

  The resin layer having a hardness of 3 H or more is obtained by, for example, applying a material such as hard acrylic resin, acrylic acid ester copolymer, urea cross-linked polyester resin, melamine resin, polycarbonate resin, etc. on the light scattering layer and drying or curing it. It can be formed. The resin layer with hardness of 3H or more is a vinyl chloride sheet, a fluorine resin sheet, a silicone resin sheet, a polyester resin sheet, a polyethylene terephthalate resin sheet, a cellulose resin sheet, a nylon resin sheet, a vinyl acetate copolymer resin sheet, etc. It can also be provided by bonding the resin film of the above to the light scattering layer.

  The sheet-like laminate of the present embodiment can be used in any of the reflection type and the transmission type when projecting a projection image. In the case of the transmission type, the substrate is preferably transparent.

  The sheet-like laminate of the present embodiment contains a flame retardant such as antimony trioxide, antimony pentoxide, aluminum hydroxide, magnesium hydroxide, melamine cyanurate, best boron, SOFA, and the like in the composition for forming a light scatterer described later. A sheet excellent in flame retardancy by adding an appropriate amount and employing a flame retardant polyvinyl chloride, flame retardant polyethene phthalate film, polyphenylene sulfide film, aramid film, flame retardant polycarbonate film, etc. as a substrate It can be made into a laminated body.

  The sheet-like laminate of the present embodiment includes, for example, a step of applying a composition for resin, a first particle, and a composition for forming a light scatterer containing the second particle on a substrate, and a coating film. And drying or curing. As another method, there may be mentioned a step of laminating a sheet-like light scattering body on a substrate.

<Composition for forming a light scatterer>
The composition for forming a light scatterer according to the present embodiment contains the resin, the first particles, and the second particles described above, and the total content of the first particles and the second particles is: the resin 100 parts by mass or less 20.0 parts by mass or more 0.01 part by mass, the particle number ratio of the particle number _{M 2} of the number of particles of the first particle _{M 1} and second particles _M 1 / M ₂ is 100 or more and 5000 or less, and the resin has a total light transmittance of 80% or more at a thickness of 20 μm.

Light scattering body composition of the present embodiment, the refractive index of the resin n _A, the refractive index of the first particles n _B, and the refractive index n _C of the second particles is represented by the above formula (1) It is preferable to satisfy the following conditions.

  The composition for light-scattering body formation of this embodiment can contain the composition for resin.

  The composition for resin can use the same thing as the composition for resin for forming the resin medium in the light-scattering body which concerns on this embodiment mentioned above. In addition, the composition for resin may contain, in place of or in combination with the above-mentioned resin, a monomer capable of forming the resin, and, if necessary, an initiator or a curing agent.

  The content of the resin composition in the composition for forming a light scattering body is preferably 25 to 99.75% by mass, and 30 to 99% by mass, based on the total amount of the composition for forming a light scattering body, from the viewpoint of dispersibility. Is more preferred.

  The total content of the first particles and the second particles in the composition for forming a light scattering material is 0.01 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the resin from the viewpoint of dispersibility. And is preferably 2.0 parts by mass or more and 15.0 parts by mass or less.

  The composition for forming a light scatterer is, if necessary, an inorganic particle other than the first particle and the second particle, an organic particle, a metal particle, a metal oxide particle, a solvent, a polymerization initiator, an anionic surfactant Cationic surfactant, nonionic surfactant, amphoteric surfactant, preservative, light stabilizer, ultraviolet absorber, antioxidant, polymerization inhibitor, silicone antifoamer, leveling agent, thickener, precipitation Anti-Sag Agent, Anti-Sag Agent, Flame Retardant, Optical Brightening Agent, Viscosity Stabilizer, pH Adjuster, Various Additives of Organic / Inorganic Pigment / Dye, Additives, Antistatic Agent, Matting Agent, etc. it can.

  Examples of solvents include aliphatic hydrocarbon solvents such as hexane, cyclohexane, methylcyclohexane, ethylcyclohexane, heptane, nonane, octane, isooctane and decane; and aromatic hydrocarbons such as benzene, toluene, xylene, cumene and ethylbenzene Solvents; diethyl ether, diisopropyl ether, methyl-tert-butyl ether, methyl cellosolve, cellosolve, butyl cellosolve, methyl carbitol, carbitol, butyl carbitol, diethyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, tetrahydrofuran, 1 Ether solvents such as 3-dioxane and 1,4-dioxane; dimethyl ketone, ethyl methyl ketone, diethyl ketone, methyl iso Ketone solvents such as chill ketone, diisopropyl ketone, diisobutyl ketone and cyclohexanone; carbonate solvents such as dimethyl carbonate, diethyl carbonate and ethylene carbonate; methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, sec-butyl Alcohol solvents such as alcohol, cyclohexanol, diacetone alcohol, 3-methoxy-3-methyl-1-butanol, ethylene glycol, propylene glycol; ethyl acetate, n-butyl acetate, isobutyl acetate, n-amyl acetate, propylene glycol Ester solvents such as monomethyl ether acetate, 3-methoxy-3-methyl-1-butyl acetate; nitrile solvents such as acetonitrile, N Aliphatic amide solvents such as N-dimethylformamide, N, N-dimethylacetamide, alkoxy-N-isopropyl-propionamide, hydroxyalkylamide, and the like; alicyclic groups such as N-methyl-2-pyrrolidone and N-ethyl-pyrrolidone Amide solvents; water and the like can be mentioned. These can be used singly or in combination of two or more.

  As the polymerization initiator, thermal radical polymerization initiators such as azo compounds and peroxides; thermal cationic polymerization initiators such as benzenesulfonic acid ester compounds and alkyl sulfonium salts; Photopolymerization initiators such as benzoin compounds and acetophenone compounds It can be mentioned.

  Although the manufacturing method of the composition for light-scattering body formation is not specifically limited, For example, the method to which 1st particle | grains and 2nd particle | grains are added and disperse | distributed to the composition for resin is mentioned.

  Examples of the method of dispersing the first particles and the second particles include a conventionally known mixing method, dispersion method and the like. In order to disperse the first particles and the second particles more reliably, it is preferable to carry out dispersion treatment using a disperser.

  As a dispersing machine, for example, mixers such as Dispa, homomixer, planetary mixer (PRIMIX "fill mix"), autorotation revolution mixer ("Awatori Neritaro" by Shinky Co., etc.), etc .; Media such as paint conditioner (made by Red Devil Co., Ltd.), ball mill, sand mill (made by Shinmaru Enterprises Co., Ltd. "Dino mill" etc.), attritor, pearl mill (made by Eirich "DCP mill" etc.), co-ball mill etc. Type disperser; wet jet mill ("Genus PY" manufactured by GENAS, "Starburst" manufactured by Sugino Machine, "Nanomizer" manufactured by Nanomizer, etc.); Medialess disperser ("Clare SS-5" manufactured by Emtechnics Co., Ltd.) , Nara Machinery "MICROS" etc.); Mill, and the like.

  The dispersion-processed composition for forming a light scatterer (dispersion liquid) can be used as a coating agent. For example, a light scattering material can be coated on the surface of a member such as an acrylic resin three-dimensional molding, a polycarbonate resin three-dimensional molding, a glass plate, an optical lens, an optical reflection mirror, an optical connector for an optical fiber. The direct beam removal effect by light scattering, the improvement of the optical coupling ratio, and the like can be realized.

  The method of applying the dispersion is not particularly limited, but can be appropriately selected according to the shape of the release substrate or the substrate, and, for example, a slide bead method, a slide curtain method, an extrusion method, a slot die method, a gravure roll The method includes an air knife method, a blade coating method, a rod bar coating method and the like.

  As a method of drying or curing the formed coating film, a method of heating with a hot air dryer, an infrared dryer, or the like can be used. When the resin composition is an aqueous emulsion, the water dispersed in the emulsion can be heated by a hot air dryer, an infrared dryer, or the like to evaporate the water contained in the coating film and cure the resin. When the composition for resin contains a monomer and a polymerization initiator, if necessary, the coating is heated to remove the solvent in the coating, and then ultraviolet light, electron beam, infrared light, visible light, X-ray, α The coating film can be cured by polymerizing the monomers by irradiation with active energy rays such as rays, γ rays and heavy particle rays.

  When a light-scattering body is formed on a peeling base material, a sheet-like light-scattering body can also be obtained by peeling off a light scattering body from a peeling base material. Although it does not specifically limit as a method to peel from a peeling base material, For example, seal peeling, physical peeling, release agent addition, etc. are mentioned.

  As a method of laminating the sheet-like light-scattering body formed on the peeling base material on a base material, bonding with an optical pressure-sensitive adhesive or an optical adhesive, hot melt bonding, etc. may be mentioned.

  The total light transmittance of the sheet-like laminate of the present embodiment is preferably 80% or more, and more preferably 85% or more. Moreover, when the thickness of a light-diffusion layer is 20 micrometers, the total light transmittance may be 80% or more, and the sheet-like laminated body of this embodiment may be 85% or more.

The sheet-like laminate of the present embodiment has a lightness L ^* value (measured at an arrangement of 20 ° incidence and 0 ° transmission) in CIE 1976 (L ^* , a ^* , b ^* ) color space of 0.5 or more Preferably, it is 0.7 or more.

(Interference noise reduction)
By the way, when the substrate is in the form of a film, image noise of optical interference such as moire fringes tends to occur in the projected image for incident light at the interface between the substrate surface and the substrate and the light scatterer, thereby reducing the image visibility. Sometimes. In particular, it is remarkable in the laser projector which has a laser light source, and laser illumination projection.

  On the other hand, the sheet-like laminate provided with the light scattering layer formed from the composition for forming a light scattering body according to the present embodiment is a light scattering layer of the light scattering layer under the influence of the dispersed first particles and the second particles. An uneven structure is formed on the surface. This uneven structure makes it possible to break the light interference condition and make it difficult to visually observe image noise of optical interference such as moire fringes in the projected image. That is, a sheet-like laminate having optical image performance with less optical interference noise, and a projection screen (particularly, a transparent screen) including the same can be realized.

(Application to a focusing screen)
In the transparent light scatterer in which two types of particles, the first particle and the second particle, are dispersed, an uneven structure is produced on the surface of the light scatterer even if it is dispersed in a resin medium. In this uneven structure, the first particle and the second particle, which are the main components of light scattering, form a random pattern in a two-dimensional surface. The random pattern means a state in which the arrangement in a wide range does not have a constant pattern and is randomly arranged. This structural asperity structure has randomness as an average optical effect. It is generally difficult to produce such an optical random pattern by a general industrial processing method such as etching with a photomask or machining.

  However, according to the composition for forming a light scatterer of the present embodiment, the first particles and the second particles can be randomly dispersed to easily form an optical random pattern. In the structural concavo-convex structure to be formed, physical random arrangement is obtained by reflecting the randomness of the optical characteristics, and moiré, unnaturalness of blur due to diffraction and color unevenness do not occur. And the dispersibility which does not have a granular feeling is obtained. Further, in the present embodiment, since the particle diameter of the first particle and the second particle is controlled, the difference in local uneven shape is small, and the occurrence of graininess and glare of the projected image can also be reduced. There is a merit.

  For example, in a focusing screen of a camera, a transparent light scatterer to be a matte surface is formed on one side, but the matte surface conventionally uses a scatterer formed by sanding or sandblasting There were many cases. When the transparent light scatterer according to the present embodiment is used as a focuser gscreen, the introduction of a random pattern of the transparent light scatterer generates moiré, unnaturalness of blur due to diffraction, and color unevenness. An image having no graininess and no graininess can be easily obtained without undergoing processing steps such as etching.

<Projection screen>
The projection screen of the present embodiment includes the light scatterer of the present embodiment described above or the sheet-like laminate of the present embodiment described above. The projection screen of the present embodiment can be a transparent screen. The transparent screen may be a transmissive transparent screen that can recognize an image from the side that transmits light to the light source, or a reflective transparent screen that can recognize an image from the side that reflects light to the light source.

  The projection screen of the present embodiment can be constituted by the light scatterer alone or the sheet-like laminate alone, but when projecting an image by the projection source, the light scatterer or the sheet-like laminate can be used in space. It is preferable to have the function which can be fixed.

  Specifically, the fixing bracket can be attached to the entire upper portion or a part of the sheet-like laminate. In addition, the fixing function is preferably such that the sheet-like laminate can be maintained flat without bending so that the image is not blurred or distorted.

  It is preferable that the projection screen of this embodiment has a storage means capable of storing the sheet-like laminate in a roll. An example of the storage means is a winding method storage device. In this case, when the projection screen is not used, the image projection unit of the sheet-like laminate can be protected, and storage properties, storage properties, portability, transportability, and the like can be improved.

  The projection screen of the present embodiment may have a weight under the sheet-like laminate in order to suppress the occurrence of deflection or distortion of the projection surface due to wind or vibration. By applying a force of 1 kg weight or more and 500 kg weight or less as a heavy load, it is easy to maintain flatness of the image projection surface and eliminate distortion of the projected image.

  The projection screen of this embodiment may be provided with a light scatterer or a sheet-like laminate on a base material having a curved surface. In this case, the light scattering body or the sheet-like laminate may be adhered or adhered to the curved surface base material, and the light scattering body is formed by directly applying the above-described composition for forming a light scattering body onto the curved surface base surface. You may

  In this case, it is possible to configure a transmissive curved transparent screen or a reflective curved transparent screen suitable for projection of a curved surface image or a stereoscopic image, and projection onto a three-dimensional curved surface. The substrate having a curved surface preferably has a total light transmittance of 85% or more. In the present embodiment, when the thickness of the light diffusion layer is 20 μm, the total light transmittance may be 85% or more.

(Reduction of speckle noise)
By the way, in a scanning coherent light source in which a light source having temporal coherency such as laser light is scanned on a screen to form an image, a spatial coherency of the screen causes a speckled pattern called speckle noise to appear. The appearance of such speckle-like image noise in the projected image may reduce the visibility of the image. The cause of this is that a light source such as a laser has temporal coherency, which interferes with the spatial coherency present in a conventional transparent screen, resulting in image noise. In order to solve this problem, use a random laser light source or a speckle diffuser, etc. to reduce the temporal coherency of the light source, or to form micro lenses or irregularities in a random arrangement on the transparent screen side to achieve spatial coherency. The lowering method is used. However, if the intensity of the light source is increased to improve the SN ratio of the projected image, the above-described method can not sufficiently reduce the coherency of the light source.

  There is known a method of reducing speckle noise by combining two microlens arrays. However, in this method, it is necessary to strictly adjust the positional relationship between the two microlens arrays (see Japanese Patent Laid-Open No. 2010-145745). In addition, when two micro lens arrays are arranged at a position where speckle noise is suppressed, there is also a problem that the resolution of a display image is lowered.

  In the projection screen according to the present embodiment, the light scattering layers of the two sheet-like laminates according to the present embodiment face each other, and the refractive index is smaller between the light scattering layers. It may have a structure disposed with the low refractive index medium interposed.

  The low refractive index medium preferably has a refractive index of 1.00 or more and 1.28 or less. Such low refractive index media include gases such as air, nitrogen, carbon dioxide gas, and argon.

  FIG. 3 is a schematic cross-sectional view showing an embodiment of the projection screen according to the present embodiment. The projection screen 30 shown in FIG. 3 has a structure in which two sheet-like laminates 20a and 20b are arranged such that their light scattering layers face each other and are separated from each other by a predetermined distance. In the present embodiment, a low refractive index medium 5 such as air is interposed between the two sheet laminates. In the present embodiment, the predetermined interval is preferably 1 μm or more and 2 μm or less.

  The projection screen of the present embodiment has the above-described structure, thereby causing fluctuation in the position vector of the optical scattering point by the first particle and the second particle in the light scatterer layer, thereby reducing the spatial coherency of the screen. be able to. Such a projection screen particularly reduces speckle-like image noise of a scanning laser projector or the like used for a head-up display, and improves image visibility in the case of recognizing an image in a direction of reflection with respect to the projection direction. It can be done.

<Image display system>
The image display system of the present embodiment includes image projection means for projecting an image, the light scatterer of the present embodiment, the sheet-like laminate of the present embodiment, or the projection screen of the present embodiment.

  According to the image display system of the present embodiment, the transparent member provided with the light scatterer, the sheet-like laminate, or the projection screen is installed between the object or the affected part and the worker during work such as processing or surgery. By doing this, when the worker observes the target or the affected area, it is possible to display and provide information based on characters and images from the outside on the background image of the target or the affected area.

  In this case, as a transparent member for providing a light scattering body, an acrylic plate, a polycarbonate plate, a cycloolefin plate, a glass plate, a transparent vinyl chloride resin sheet, a transparent fluorine resin sheet, an acrylic resin sheet, a cycloolefin resin sheet, a polyethylene resin sheet, A polypropylene resin sheet etc. are mentioned.

  In the image display system of the present embodiment, the detecting means for detecting the approach of a person or an object, and the image scattering means to the light scatterer or the projection screen when it is determined that the person or the object approaches based on the information from the detecting means. And means for projecting an image.

  According to the image display system of the present embodiment, for example, a light scatterer or a sheet-like laminate is attached to a transparent door or window of a building to constitute a transparent screen, and an objective sensor attached to the vicinity, an interpersonal sensor, When it is determined that a person or object has approached by a detection means such as a surveillance camera, a projector such as a projector, light or display installed provides information or a warning to a transparent door or window of a building. It can be displayed.

  The light scatterer, the sheet-like laminate, and the projection screen according to the present embodiment are excellent in transparency, so that the intruder or the approacher does not affect the transparency or the visibility of the door or window of the building. You can get the crime prevention effect of the building that can issue a warning. In addition, when applied as a digital signage medium of a window display, when a customer approaches a store, product information and store information can be displayed for the client, and an advertisement effect can be generated. Furthermore, when a person approaches a transparent door at night, it can be used as a device that projects light on the transparent door to make the approaching person recognize the presence of the door and avoid an inadvertent collision.

<Application to angiography>
Red blood cells in human blood contain hemoglobin and have a high near infrared absorption rate. Using this, it is possible to capture a blood vessel image up to a depth of about 10 mm from the skin surface of a human by a near infrared camera and an image processing apparatus. The photographed blood vessel image can be directly projected on the surface of human skin by a projector, the position of the vein can be directly displayed as an image on human skin, and the insertion position of the injection needle can be directly grasped visually. Vascular visualization device "VeinViewer" (registered trademark) manufactured by Christy Medical Holdings Inc., and non-contact type vein visualization device "StatVein" manufactured by Techno Medica, Inc. "(Registered trademark)" is known.

  In the present embodiment, the composition for forming a light scatterer of the present embodiment can be directly applied to human skin and dried to form a transparent screen on the skin. In this case, it is desirable that the resin in the composition for forming a light scatterer does not penetrate the skin, and an elastic elastomer such as elastic silicone which does not inhibit the insertion of the needle even when the injection needle is inserted. Moreover, it is desirable that it is resin which is easy to peel off after use. When the blood vessel image of the subject imaged with the VeinViewer is projected on the skin surface of the subject by a projector on a transparent screen formed on the skin, the projected blood vessel image can be clearly seen even in a bright environment under normal fluorescent light be able to. In addition, when the particles dispersed in the light scatterer are diamonds, the infrared light absorptivity of the screen is low, and the blood vessel image on the back can also be observed with a near infrared camera.

<Application to vehicle parts>
The light-scattering body, the sheet-like laminate, and the projection screen of the present embodiment can also be used as a member for a vehicle. As an example, the light scatterer, sheet-like laminate or projection screen of this embodiment is adhered to the surface of the side and rear window, and the light curtain function for image display and privacy protection on the side and rear window is provided. Can. In addition, when the driver causes sunlight as a back light at the time of driving and becomes an obstacle to driving, a light scatterer, a sheet-like laminate or a projection screen can be used as a sun visor as alleviation of the back light. In this case, by reducing the total light transmittance to about 85%, the light scatterer, the sheet-like laminate, or the projection screen scatters the sunlight, thereby reducing the illuminance of the sunlight and securing the visibility during operation. can do. Moreover, in order to project information to a front window or drive operation panel vicinity with a projector, a transparent screen can also be comprised in front window or drive operation panel vicinity with a light-scattering body, a sheet-like laminated body, or a projection screen. Furthermore, the directivity of the light source can be reduced and the light flux can be expanded by arranging the light scatterer, the sheet-like laminate or the projection screen of the present embodiment in front of the laser light and the LED light.

<Application to building components>
The light-scattering body, the sheet-like laminate, and the projection screen of the present embodiment can also be used for a building member. As an example, a sheet-like laminate can be attached to a glass window, an image can be projected by a projector, and it can be used as advertisement and information provision of a store. As another example, a sheet-like laminate is attached to the transparent partition of the office and used as a transparent screen for a projector, or light is irradiated to the transparent partition for security and privacy protection, and used as a light curtain. It is also possible to

  EXAMPLES Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited by these examples.

  The following materials were prepared in order to prepare a resin composition for forming a light scatterer and a sheet-like laminate.

[resin]
Urethane resin composition: Evaphanol HA-170 (manufactured by Nikka Chemical Co., Ltd., non-volatile content 36.5% by mass, refractive index 1.50, total light transmittance 91.0% at a thickness of 20 μm)
Acrylic resin composition: EK-61 (manufactured by Siden Chemical Co., Ltd., 39.8% by mass of nonvolatile matter, refractive index 1.49, total light transmittance 90.1% at thickness 20 μm) is diluted with ion exchanged water , The non volatile matter concentration adjusted to 36.5 mass%

[First particle]
Diamond 1: (single crystal diamond, manufactured by RZ, median diameter 100 nm, specific gravity 3.53, carbon concentration 98.34%)
Diamond 2: (single crystal diamond, manufactured by RZ, median diameter 200 nm, specific gravity 3.53, carbon concentration 98.76%)
Diamond 3: (polycrystalline diamond, manufactured by RZ, median diameter 200 nm, specific gravity 3.51, carbon concentration 99.69%)
Titanium oxide: (manufactured by Sakai Chemical Co., Ltd., model number: SA-1, median diameter 150 nm, specific gravity 3.90, refractive index 2.52)

[Second particle]
Diamond 4: (single crystal diamond, manufactured by RZ, median diameter 600 nm, specific gravity 3.53, carbon concentration 98.63%)
Diamond 5: (polycrystalline diamond, manufactured by RZ, median diameter 600 nm, specific gravity 3.51, carbon concentration 99.80%)
Diamond 6: (polycrystalline diamond, manufactured by RZ, median diameter 800 nm, specific gravity 3.51, carbon concentration 99.64%)

[Base material]
Polyethylene terephthalate film (PET) (Toyobo Co., Ltd., thickness 100 μm)

<Preparation of Resin Composition for Forming Light Scattering Body>
(Resin composition 1)
In a 200 ml stainless steel pot, 0.475 mass% of diamond 2, 0.025 mass% of diamond 5, and 99.5 mass% of Evaphanol HA-170 were added, and a jet mill (SUGINO HJP-25003, Sugino) Jet milling was carried out under the conditions of a pressure of 80 MPa and two passes using a machine manufactured by Machine Co., Ltd., followed by filtration at # 2000, thereby preparing a resin composition 1. In addition, no aggregates were observed in the cocoon.

(Resin composition 2)
A resin is prepared in the same manner as resin composition 1 except that 1.9% by mass of diamond 2, 0.1% by mass of diamond 5 and 98% by mass of Evaphanol HA-170 are added to a stainless steel pot. Composition 2 was prepared. In addition, no aggregates were observed in the cocoon.

(Resin composition 3)
A resin is prepared in the same manner as resin composition 1 except that 4.75 mass% of diamond 2, 0.25 mass% of diamond 5, and 95 mass% of Evaphanol HA-170 are added to a stainless steel pot. Composition 3 was prepared. In addition, no aggregates were observed in the cocoon.

(Resin composition 4)
A resin composition 4 was prepared in the same manner as the resin composition 2 except that cibinol EK-61 (98 mass%) was added in place of the evaphanol HA-170 of the resin composition 2. In addition, no aggregates were observed in the cocoon.

(Resin composition 5)
Resin composition 5 was prepared in the same manner as resin composition 2 except that diamond 1 (1.9 mass%) was added instead of diamond 2 of resin composition 2. In addition, no aggregates were observed in the cocoon.

(Resin composition 6)
Resin composition 6 was prepared in the same manner as resin composition 2 except that diamond 4 (0.1 mass%) was added instead of diamond 5 of resin composition 2. In addition, no aggregates were observed in the cocoon.

(Resin composition 7)
A resin composition 7 was prepared in the same manner as the resin composition 2 except that diamond 6 (0.1 mass%) was added instead of the diamond 5 of the resin composition 2. In addition, no aggregates were observed in the cocoon.

(Resin composition 8)
A resin composition 8 was prepared in the same manner as the resin composition 2 except that titanium oxide (1.9 mass%) was added instead of the diamond 2 of the resin composition 2. In addition, no aggregates were observed in the cocoon.

(Resin composition 9)
Resin composition 9 was prepared in the same manner as resin composition 2 except that diamond 3 (1.9 mass%) was added instead of diamond 2 of resin composition 2. In addition, no aggregates were observed in the cocoon.

(Resin composition 10)
Resin composition in the same manner as resin composition 2 except that diamond 3 (1.9 mass%) and diamond 4 (0.1 mass%) are added instead of diamond 2 and diamond 5 of resin composition 2 10 was prepared. In addition, no aggregates were observed in the cocoon.

(Resin composition 11)
Resin composition 11 in the same manner as resin composition 2 except that diamond 2 and diamond 5 of resin composition 2 were added so that the respective contents would be 1.95 mass% and 0.05 mass%. Was prepared. In addition, no aggregates were observed in the cocoon.

(Resin composition 12)
Resin composition 12 in the same manner as resin composition 2 except that diamond 2 and diamond 5 of resin composition 2 are added so that the contents thereof become 1.987 mass% and 0.013 mass%, respectively. Was prepared. In addition, no aggregates were observed in the cocoon.

(Resin composition 13)
A resin composition 13 was prepared in the same manner as the resin composition 2 except that diamond 1 (2.0 mass%) was added instead of the diamond 2 and the diamond 5 of the resin composition 2. In addition, no aggregates were observed in the cocoon.

(Resin composition 14)
A resin composition 14 was prepared in the same manner as the resin composition 2 except that diamond 3 (2.0% by mass) was added instead of the diamond 2 and the diamond 5 of the resin composition 2. In addition, no aggregates were observed in the cocoon.

(Resin composition 15)
A resin composition 15 was prepared in the same manner as the resin composition 2 except that diamond 6 (2.0 mass%) was added instead of the diamond 2 and the diamond 5 of the resin composition 2. In addition, no aggregates were observed in the cocoon.

(Resin composition 16)
Resin composition 16 in the same manner as resin composition 2 except that diamond 2 and diamond 5 of resin composition 2 are added so that the contents thereof become 1.5 mass% and 0.5 mass%, respectively. Was prepared. In addition, no aggregates were observed in the cocoon.

The particle number ratio (particle number M _{1 of first} particle / particle number M _{2 of second} particle) in the particle ratio shown in the table is the content C _{1 of} the first particle and the second particle, and From the values of C ₂ , specific gravity _{1 1} and _{2 2} , and median diameters r ₁ and r ₂ of the first particle and the second particle, the volume density was calculated according to the equation shown below.
Particle number ratio M ₁ / M ₂ = (C ₁ × ρ ₂ × r ₂ ³ ) / (C ₂ × ρ ₁ × r ₁ ³ )

<Preparation of sheet-like laminate>
Example 1
The resin composition 1 was coated on one side of the substrate using a slide bead coater (tabletop coater, model TC-3 manufactured by Mitsui Electric Seiki Co., Ltd.) so that the concentration of solid content would be 50 g / m ² . Then, it was placed in an oven at 90 ° C. for 1 minute and dried to prepare a sheet-like laminate having a light scattering layer comprising a light scattering material provided on a substrate. The thickness of the light scattering layer was 14 μm.

(Example 2)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 2 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Example 3)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 3 was used in place of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Example 4)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 4 was used in place of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Example 5)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 5 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Example 6)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 6 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Example 7)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 7 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Example 8)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 8 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Example 9)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 9 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Example 10)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 10 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Example 11)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 11 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Example 12)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 12 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Comparative example 1)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 13 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Comparative example 2)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 14 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Comparative example 3)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 15 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

(Comparative example 4)
A sheet-like laminate was produced in the same manner as in Example 1 except that the resin composition 16 was used instead of the resin composition 1. The thickness of the light scattering layer was 14 μm.

<Evaluation of sheet-like laminate>
The total light transmittance, the haze value, and the L ^* (lightness) of the sheet-like laminates of Examples 1 to 12 and Comparative Examples 1 to 4 were measured according to the following methods. In addition, the sharpness was evaluated on the image viewed from the projector side when the image was projected by the projector and the image viewed from the opposite side of the projector side.

[Total light transmittance]
The total light transmittance of the light scattering body was measured using a turbidimeter (manufactured by Nippon Denshoku Kogyo Co., Ltd., part number: NDH-5000) in accordance with JIS K7361-1 (1997).

[Haze value]
The diffused light transmittance of the light scattering material was measured according to JIS-K7105 (1981) using a haze meter (manufactured by Suga Test Instruments, product number: HGM-2DP). Using this diffused light transmittance and the total light transmittance measured above, the haze value was determined from the following equation.
H = [Td / Tt] × 100 (%)
[H: haze, Td: diffuse light transmittance, Tt: total light transmittance]

  With regard to the transparency, those having a high total light transmittance and a low haze value are regarded as having high transparency, and a total light transmittance of 75% or more and a haze value of 30% or less are regarded as passing.

[L ^* (brightness)]
The lightness of the sheet-like laminate was measured according to the following procedure using a variable angle photometer (manufactured by Nippon Denshoku Kogyo Co., Ltd., product number: GC5000). The incident angle of the light source was set to 20 degrees, and the transmitted light intensity in the direction of 20 degrees was set to 100 with nothing placed on the measurement stage. The obtained sheet-like laminate was placed on a measurement stage, and the L ^* value of the transmitted light at 0 ° was measured with the incident angle of the light source kept at 20 °, and this was taken as the lightness. An L ^* value of 0.50 or more was accepted.

[(1) Image sharpness seen from the projector side (transmission mode]
An image is projected on a screen with a digital projector (Epson, product name: EH-TW410), the image projected on the screen is viewed from the projector side, and the sharpness of the image is evaluated in four stages according to the following criteria did.
(Standard)
1: The outline of the projected image can be seen very clearly.
2: The outline of the projected image can be seen sufficiently.
3: The outline of the projected image is thin and difficult to see.
4: The outline of the projected image does not look blurry.
The said criteria made 1 and 2 pass.

[(2) Sharpness of the image viewed from the side opposite to the projector side (reflection mode)]
An image is projected on a light diffusion film with a digital projector (Epson, product name: EH-TW410), and the image projected on the screen is viewed from the side opposite to the projector side, and the sharpness of the image is based on the following criteria It was evaluated in 4 steps by
(Standard)
1: The outline of the projected image can be seen very clearly.
2: The outline of the projected image can be seen sufficiently.
3: The outline of the projected image is thin and difficult to see.
4: The outline of the projected image does not look blurry.
The said criteria made 1 and 2 pass.

  The results shown in Table 4 indicate that the sheet-like laminate having the light scatterer according to the present invention has high transmittance and high brightness of the image, and is found to be useful as a transparent screen for a projector. . Moreover, it has been found that the sheet-like laminate having the light scatterer according to the present invention can obtain high image quality as reflective type or transmissive type in sensory evaluation of image quality.

<Production of transparent screen>
First, a composition for forming a light scatterer was prepared, and a sheet-like laminate was produced using it.

(Preparation of composition for forming light scatterer)
A jet mill (Starburst Mini, Sugino Machine Co., Ltd.) is added to a 200 ml stainless steel pod in such a manner that 1.9% by weight of diamond 2, 0.1% by weight of diamond 5, and 98% by weight of Evaphanol HA-170 are added. Dispersion treatment was performed to prepare a composition for forming a light scatterer.

(Preparation of sheet-like laminate)
In order to use the resin composition for light-scattering body formation prepared above as a coating liquid, after filtering with a filter (3M company make, Betapure AU), the dispersed state was maintained by the ultrasonic homogenizer. This is coated on a 1500 mm wide, 2000 m long optical PET film (Toyobo Co., Ltd., thickness 100 μm, total light transmittance 91%) with a two-roll coater, dried in an infrared drying oven, and wound up. The sheet-like laminate was obtained. The coating thickness was set to 16 μm after drying.

Example 13 Fixed Transparent Screen
In order to make the projection surface flat, the sheet-like laminate obtained above is cut to a width of 2000 mm and a length of 1500 mm, and the upper end and the lower end are fixed to a metal frame (made of aluminum, 2050 mm wide and 1550 mm long), and a transparent screen Made. In addition, in order to be able to suspend from the ceiling on the upper part of the metal frame, three hooks for suspension are fixed (each 50 mm from the left and right ends and the middle position).

  The transparent screen was suspended from the ceiling and fixed in space, and an image was projected with an optical projector (RICOH PJ WUL 5670). It has been confirmed that it can also be used as a transmissive transparent screen that can recognize an image from the side that transmits to a light source, or as a reflective transparent screen that can recognize an image from the side that reflects to a light source. In addition, it was possible to project a high-definition image, and it was possible to observe an image without blurring or distortion from almost all directions such as 170 ° or more in both forward and backward viewing angles.

(Example 14: Roll-winding transparent screen)
A winding method storage device capable of storing the sheet-like laminate in a roll shape is provided, and when the transparent screen is not used, the sheet-like laminate is stored to protect the image projection unit from scratches and the like. Specifically, the sheet-like laminate obtained above is cut to a width of 2000 mm and a length of 1500 mm, and the upper end is a cylindrical winding device (width 1560 mm, diameter 45 mm, equipped with a manual winding device with a chain and gears) And a rod-like weight (length 1550 mm, diameter 30 mm, weight 1.5 kg) was fixed to the lower end. Hanging fixtures are fixed at two places (150 mm from the left and right ends, respectively) at the top of the winding device so that they can be fixed to a ceiling or a hanging fixed leg. The total weight was 5.5 kg, and it was confirmed that not only storage but also human beings can carry and transport alone.

(Example 15: Curved surface type transparent screen)
By applying a pressure-sensitive adhesive (trade name "Gelpoly") to the back surface of the sheet-like laminate obtained above, slight tackiness was imparted. A sheet-like laminate is attached to a transparent acrylic half cylinder (thickness 5 mm, diameter 1000 mm, sector angle 45 °, length 800 mm, total light transmittance 87%) without air bubbles at the interface to form a curved transparent screen I made it. The curved transparent screen can be used as a transmissive transparent screen or a reflective transparent screen.

(Example 16: Transparent screen for projector)
The sheet-like laminate obtained above was applied to a transparent screen for a projector. When a gray standard image was projected by a laser projector (Ricoh Corporation, RICOH PJ WXL 4540), no moiré fringes were observed. When projected using a transparent screen (KALEIDO SCREEN, manufactured by JXTG Energy Co., Ltd.), moiré fringes appeared.

(Example 17: Reduction of speckle noise)
The resin composition 1 was coated on one side of the substrate using a slide bead coater (tabletop coater, model TC-3 manufactured by Mitsui Electric Seiki Co., Ltd.) so that the concentration of solid content would be 50 g / m ² . Then, it was placed in an oven at 90 ° C. for 1 minute and dried to prepare two sheet-like laminates provided with a light scattering layer composed of a light scattering body on a substrate. The thickness of the light scattering layer was 20 μm.

  Next, two sheet-like laminates were stacked via air so that the light scattering layers face each other, to prepare a transparent screen having the same structure as the projection screen shown in FIG. The distance between the light scattering layers was 1.2 μm.

  Speckle noise was measured by irradiating the above-mentioned transparent screen with laser light (red pattern using an RGB three-wavelength mixed laser light source) modulated by a video signal. The speckle contrast value on the projected image was 22.3%.

(Example 18: Reduction of speckle noise)
A transparent screen was produced in the same manner as in Example 17 except that the resin composition 3 was used in place of the resin composition 1. The speckle noise was measured in the same manner as in Example 17. As a result, the contrast value was 13.5%.

(Example 19: Reduction of speckle noise)
The sheet-like laminate of Example 17 and the sheet-like laminate of Example 18 were combined to produce a transparent screen. The speckle noise was measured in the same manner as in Example 17. As a result, the contrast value was 8.7%. This contrast value was close to the level at which speckle noise can not be perceived by the human eye (red pattern for standard contrast test: approximately 8%).

(Example 20: Image display system for processing work)
A sheet-like laminate obtained in the same manner as in Example 2 was cut into a length of 900 mm and a width of 450 mm, and fixed to an aluminum frame to constitute a transparent screen.

  As shown in FIG. 4, a transparent screen 40 was installed between the worker 9 and the object 7 at an angle of 15 ° with respect to the object 7 on the work bench 6. From the horizontal method, an image was projected from below onto a transparent screen by Projector 8 (RICOH PJ WUL 5670, manufactured by Ricoh Co., Ltd.). In addition, the projector was arrange | positioned so that direct transmission light and reflected light of a projector might not be directly injected into a worker's eye, when projecting image information on a transparent screen.

  The above-mentioned image display system can ensure transparency that does not become an obstacle to operation on the work, and the operator can sufficiently obtain the image on the transparent screen even in environmental lighting (JIS lighting standard 300 lux or more) in the work environment I could recognize it.

(Example 21: Alarm display device)
A slight pressure-sensitive adhesive (trade name "Gelpoly") is applied to a back surface of the sheet-like laminate obtained in the same manner as in Example 2 to a thickness of 50 μm, and a transparent glass door of a building (thickness 8 mm) , A width of 900 mm, and a length of 1500 mm) were attached to form a transparent screen. Moreover, the light with an objective sensor (sensor light: 2 light type LED, human-sense light: LCL-52) was attached to the door upper part.

  In the above-mentioned alarm display device, when a person or an object approaches, the sensor senses and the light is activated, and the light is emitted to the transparent screen installed in the door. This makes it possible to visually warn the approaching person of the door. In addition, the above-mentioned alarm display device projects light on a transparent door when a person approaches the transparent door at night, makes the approaching person recognize the presence of the door, and is also an apparatus for avoiding an inadvertent collision. Available.

(Example 22: advertisement display device)
A near-infrared laser sensor (made by DENSO, ZD-LS100M) is installed near the door instead of the light with an objective sensor above, and a small laser projector (made by SONY, LSPX-P1) when a person approaches. Changed the system to operate, and configured the advertising display device.

  The above-mentioned advertisement display device can display product information and store information on the transparent door to the customer when the customer approaches the store, and uses it as digital signage of a window display, and advertising media By displaying it, it can be expected to produce advertising effects.

Example 23 Display Device with Whiteboard Function
A thin adhesive (trade name "Gelpoly") was applied to the back surface of the sheet-like laminate obtained in the same manner as in Example 2 to a thickness of 50 μm, and it was transparent fixed to a movable iron frame stand. It stuck on the acrylic board (5 mm in thickness, 1000 mm in length, 1200 mm in width), and comprised the transparent screen. Next, a whiteboard coating agent (SCST100, manufactured by SST, SC1001, hardness 3H) was coated on the surface of the light scattering layer of the stuck sheet-like laminate, and writing was possible with a board marker.

  The display device with the whiteboard function described above can not only simultaneously view the background image and the projection image by the projector, but also allows the operator to write characters and figures with the board marker. It is also possible to erase the writing with a dedicated sponge eraser.

DESCRIPTION OF SYMBOLS 1 ... 1st particle | grain, 2 ... 2nd particle | grain, 3 ... Resin medium, 4 ... Base material, 5 ... Low-refractive-index medium (air layer), 6 ... Work bench, 7 ... Target object, 8 ... Projector, 9 ... Workers 10: Light scatterers 20, 20a, 20b: Sheet-like laminates 30, 30: Projection screen, 40: Transparent screen.

Claims (16)

A resin, a first particle having a median diameter of 50 nm to 360 nm, and a second particle having a median diameter of 500 nm to 1.5 μm and having a diamond structure,
The total content of the first particles and the second particles is 0.01 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the resin,
The first is the particle number ratio _M 1 / _{M 2} of the particle number _{M 2} of the number of particles _{M 1} and the second particles having a particle is 100 to 5,000,
The composition for forming a light scatterer, wherein the resin has a total light transmittance of 80% or more at a thickness of 20 μm. Satisfying a refractive index n _A of the _resin, the refractive index n _B of the first _particles, and the refractive index n _C of the second particles, represented by the following formula (1), according to claim 1 Composition for forming a light scatterer.
0.15 <| n _B −n _A | ≦ n _C −n _A <1.15 (1)   The composition for forming a light scatterer according to claim 1 or 2, wherein the first particles and the second particles are diamonds, and the carbon concentration is 90% by mass or more. A resin medium, first particles dispersed in the resin medium, having a median diameter of 50 nm or more and 360 nm or less, and a median diameter of 500 nm or more and 1.5 μm or less dispersed in the resin medium A light scatterer comprising a second particle having a diamond structure,
The total content of the first particles and the second particles is 0.01 parts by mass or more and 20.0 parts by mass or less with respect to 100 parts by mass of the resin medium,
The first is the particle number ratio _M 1 / _{M 2} of the particle number _{M 2} of the number of particles _{M 1} and the second particles having a particle is 100 to 5,000,
A light scatterer, wherein the total light transmittance of the light scatterer is 80% or more. The refractive index n _{A of} the resin medium, the refractive index n _B of the first particle, and the refractive index n _C of the second particle satisfy the condition represented by the following formula (1): Light scatterer as described.
0.15 <| n _B −n _A | ≦ n _C −n _A <1.15 (1)   The light-scattering body of Claim 4 or 5 whose said 1st particle | grains and said 2nd particle | grains are diamonds, and whose carbon concentration is 90 mass% or more.   The sheet-like laminated body provided with the base material and the light-scattering layer which consists of a light-scattering body as described in any one of Claims 4-6 provided on this base material.   The sheet-like laminate according to claim 7, further comprising a resin layer having a hardness of 2H or more on at least one outermost surface.   The sheet-like layered product according to claim 7 or 8 in which said substrate has a curved surface.   A projection screen comprising the sheet laminate according to any one of claims 7 to 9.   11. The projection screen according to claim 10, which is a transmissive transparent screen.   11. The projection screen according to claim 10, which is a reflective transparent screen.   The projection screen according to any one of claims 10 to 12, further comprising storage means capable of storing the sheet-like laminate in a roll shape.   The two sheet-like laminates according to claim 7 are in a state in which the light scattering layers are opposed to each other, and a low refractive index medium having a smaller refractive index than the respective light scattering layers is interposed between the light scattering layers. Projection screen, having a arranged structure;   An image projection means for projecting an image, a light scatterer according to any one of claims 4 to 6, a sheet-like laminate according to any one of claims 7 to 9, or And a projection screen according to any one of the preceding claims. A detection means for detecting the approach of a person or an object, and the light scattering body, the sheet-like laminate or the projection screen from the image projection means when it is determined that the person or an object approaches based on the information from the detection means The image display system according to claim 15, further comprising: means for projecting an image on the image.

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