JP6061796B2 - Laminate for use in see-through transmissive screen - Google Patents

Description

  The present invention has high transparency and excellent visibility of the image projected from the projector, and has excellent workability when being applied to an object to be bonded such as glass or a plastic plate, or when being peeled from the substrate to be bonded. The present invention relates to a transparent see-through screen laminate capable of being seen through.

  At present, so-called rear projection type transmission screens, in which the image projected from the projector is viewed from the opposite side of the projector across the screen, are becoming popular in place of advertising media such as posters, signs, signboards, etc. is there. In recent years, there has been a great deal of attention as digital signage capable of projecting on a large screen digital contents that require no posting, can change contents instantly, and require not only static but also dynamic posting.

  In particular, most of the store's show windows face the roads through which customers pass, and if they can be replaced with digital signage that uses the windows as large screens, they are very useful as advertising media. There is an increasing need for a pasting type, so-called transmission screen for window display.

  Examples of the transmissive screen for window display include a transmissive screen having a light diffusing layer containing porous particles (Patent Document 1), a light diffusing fine particle and a resin binder, and a part of the light diffusing fine particle is irradiated with light. Projecting from a projector such as a transmissive screen (Patent Document 2) having a haze of 80% or more, a total light transmittance of 60% or more and a mirror glossiness of at least 10% or less by projecting from the diffusion layer A transmissive screen with a wide viewing angle and good visibility from the projector side has been proposed.

  In addition, among the transmissive screens, the transmissive screen that allows the user to see the products in the store through the window can be replaced with digital signage as necessary while displaying the products. It is useful and has received much attention.

  As such a transmissive screen that can be seen through, a transparent resin binder and an average particle diameter of 1.0 to 10 μm and a relative refractive index n with respect to the refractive index of the transparent resin binder are 0.91 <n <1.09 (provided that , N ≠ 1) has been proposed (for example, Patent Documents 3 and 4), and the inventor has higher transparency and visual recognition of the image projected from the projector. In order to achieve compatibility, a transparent transmission screen having a light diffusing layer on at least one surface of a light transmissive support, the light diffusing layer containing light diffusing fine particles and xerogel A transmissive screen was proposed as Japanese Patent Application No. 2012-046170.

  On the other hand, in the transmissive screens for window displays, generally, when the transmissive screen is attached to the adherend substrate, the bonding surface of the adherend substrate and the adhesive of the transmissive screen are prevented so that air does not enter. The surface of the layer is preferably sprayed with water containing a surfactant, and after adhering both sides, the water is scraped off with a squeegee together with air from the transmission screen side, and further adhered sufficiently. Therefore, drying for several days to several weeks is generally performed (hereinafter, this method of sticking is referred to as water sticking). However, this water pasting operation is complicated and time-consuming as described above, and when the transmission type screen is no longer necessary, the transmission type screen is peeled off and the adhesive remaining on the substrate to be bonded is cleaned cleanly. There was also a problem that the workability of a series of pasting and peeling was very bad.

JP 2006-119318 A JP 2005-024942 A JP 2001-242546 A JP 2007-034324 A

  The purpose of the present invention is high transparency and excellent visibility of the image projected from the projector, and workability when pasting to or peeling from the adherend substrate such as glass or plastic plate. Provided is a transparent screen laminate that can be seen well.

The object is achieved by the following invention.
(1) has a light diffusing layer on one surface of a light transmissive support, a transparent adhesive layer on the other surface and the separate substrate is a laminate for use in sequentially laminated see-through transmission screen The light diffusing layer contains light diffusing fine particles and xerogel, the light diffusing fine particles are supported on the xerogel, and the transparent adhesive layer is patterned in a dot shape or a block shape so as to be discretely arranged. A laminate used for a see-through transmissive screen characterized by comprising:

  According to the present invention, high transparency and excellent visibility of an image projected from a projector, and good workability when being attached to or peeled off from an adherend substrate such as glass or plastic plate. A transparent screen laminate that can be seen through can be provided.

Schematic sectional view showing an embodiment of a transmission screen laminate of the present invention

The present invention is described in detail below.
In the present invention, “perceivable” means that the haze value of the transmission screen is 60% or less. A more preferred haze value is 50% or less.

The haze value is a value defined below in JIS-K7136, and the lower the value, the better the transparency. Note that the haze value of the transmission screen of the present invention does not include the value of the separate substrate. This is because when the transmissive screen laminate is mounted, the separate substrate is mounted in a removed state.
H = (Td / Tt) × 100 (%)
H: Haze value Td: Diffuse light transmittance Tt: Total light transmittance

  FIG. 1 shows an embodiment of the transmission screen laminate of the present invention. As shown in FIG. 1, the transmissive screen laminate in the present invention has a light diffusing layer 3 containing light diffusing fine particles 2 and xerogel 5 on one surface of a light transmissive support 4, and the other side. It has the transparent adhesive layer 8 which has the adhesion part 6 patterned on the surface in the shape of a dot or a block, and arrange | positioned discretely, and the separate base material 7 (the figure before affixing in the figure). When affixing to the adherend substrate 10 using the transmissive screen laminate, the separate substrate 7 is peeled off, and the exposed transparent adhesive layer 8 and the adherent substrate 10 are overlaid and attached (see FIG. Middle, figure after pasting). At this time, the transparent adhesive layer 8 having the adhesive portions 6 which are patterned in a dot shape or a block shape and are discretely arranged can be easily removed without sticking the air between the substrates 10 to be adhered. it can.

  The “transmission type” of the transmission type screen laminate of the present invention is JIS-K7361-1 of the screen in a state where the above-described separate substrate is removed, that is, the screen in a state of being bonded to the adherend substrate. It means that the prescribed total light transmittance exceeds 50%. More preferably, it means exceeding 65%. The total light transmittance of the transmission screen of the present invention does not include the value of the separate substrate. This is because when the transmissive screen is mounted on the adherend substrate, the separate substrate is mounted in a removed state.

  In the transmissive screen laminate in the present invention, the light diffusion layer contains light diffusing fine particles and xerogel.

  Normally, when applying light diffusing fine particles to a light transmissive support, a resin binder for binding the light diffusing fine particles is required. The coating liquid containing light diffusing fine particles and resin binder is diluted with an organic solvent or water for the purpose of adjusting the viscosity for ensuring the coating property, and applied to the light transmissive support, dried, or photocured. In general, a resin or an electron beam curable resin is coated as a resin binder without a solvent. In the light diffusion layer coated by such a method, since the refractive index of both the resin binder and the light diffusing fine particles is generally around 1.50, the relative refractive index of the light diffusing fine particles with respect to the resin binder is It becomes low and efficient light diffusion hardly occurs. On the other hand, in the present invention, by allowing the light diffusing fine particles to be supported on the xerogel, there are xerogel voids (air having a refractive index of 1.0) on the surface of the light diffusing fine particles, and the relative refraction of the light diffusing fine particles to the air. Since the rate becomes very high, the light diffusing fine particles can be efficiently diffused, and a transmissive screen with a high viewing angle of the image projected from the projector can be provided.

  In JP-A-2006-119318 and JP-A-2005-024942, a light diffusing layer in which light diffusing fine particles are held with a resin binder is described, and light diffusing fine particles are formed with xerogel. It is essentially different from the light diffusion layer of the present invention that is carried.

  The light diffusing fine particles contained in the light diffusion layer in the present invention can be used regardless of organic fine particles and inorganic fine particles as long as they have the ability to diffuse light. It is preferable to use so-called single particle-dispersible organic fine particles having no particle diameter, and the shape is preferably spherical.

  The light diffusibility of the light diffusing fine particles depends on the specific surface area in addition to the above relative refractive index. The specific surface area depends on the average primary particle size of the light diffusing fine particles, and in the case of single particle dispersible fine particles, it can be easily calculated from the average primary particle size and specific gravity.

  The average primary particle diameter of the light diffusing fine particles is preferably 20 μm or less, more preferably 8.5 μm or less, and further preferably 2.75 μm or less. When light diffusing fine particles having an average primary particle diameter of 2.75 μm or less are used, particularly excellent transparency can be obtained. The lower limit is preferably 0.2 μm or more. The average primary particle diameter as used in the present invention can be measured by photography using a transmission electron microscope. However, in the case of light diffusing fine particles having no secondary aggregate particle diameter, a laser scattering type particle size distribution meter (for example, The number median diameter can also be measured using LA910 manufactured by HORIBA, Ltd.

  Further, the refractive index of the light diffusing fine particles is preferably 1.30 or more, and more preferably 1.40 or more.

  Examples of the organic fine particles include acrylic polymer, styrene-acrylic copolymer, vinyl acetate-acrylic copolymer, vinyl acetate polymer, ethylene-vinyl acetate copolymer, chlorinated polyolefin polymer, ethylene-vinyl acetate- Multi-component copolymers such as acrylic, SBR, NBR, MBR, carboxylated SBR, carboxylated NBR, carboxylated MBR, polyvinyl chloride, polyvinylidene chloride, polyester, polyolefin, polyurethane, polymethacrylate, polytetrafluoroethylene, polymethacryl It can be selected widely from conventionally known ones such as methyl acid, polycarbonate, polyvinyl acetal resin, rosin ester resin, episulfide resin, epoxy resin, silicone resin, silicone-acrylic resin, melamine resin, etc. . Moreover, what coated fine particle surfaces, such as a melamine resin and an acrylic resin, with inorganic fine particles, such as a silica, can also be used. Further, even when composite particles composed of such organic fine particles and a small amount of inorganic fine particles (in which the proportion of inorganic fine particles is less than 50% by mass) are used, it can be substantially regarded as organic fine particles and used. Those in which a sulfur atom is introduced into the monomer of these polymers for the purpose of increasing the refractive index, and those in which a fluorine substituent is introduced to improve the weather resistance or lower the refractive index can also be used.

  Inorganic fine particles include silica, alumina, rutile titanium dioxide, anatase titanium dioxide, zinc oxide, zinc sulfide, lead white, antimony oxides, zinc antimonate, lead titanate, potassium titanate, zirconium oxide, cerium oxide, Hafnium oxide, tantalum pentoxide, niobium pentoxide, yttrium oxide, chromium oxide, tin oxide, molybdenum oxide, ATO, ITO, oxide glass such as silicate glass, phosphate glass, borate glass, etc. These composite oxides or composite sulfides can also be widely used. In the case of inorganic fine particles having photocatalytic activity, such as titanium oxide and zinc oxide, those having a very thin surface coated with silica, alumina, boron or the like can be used. Further, even when composite particles composed of inorganic fine particles and a small amount of organic polymer (the proportion of organic fine particles is less than 50% by mass) are used, they can be regarded as inorganic fine particles substantially. The inorganic fine particles used as the light diffusing fine particles are preferably single particle dispersible inorganic fine particles.

  In the present invention, the organic fine particles and the inorganic fine particles used as the light diffusing fine particles can be used singly or as a mixture of a plurality of types, or both the organic fine particles and the inorganic fine particles can be mixed and used. .

The coating amount of the light diffusing fine particles of the present invention is not particularly limited as long as the haze value of the entire screen is 60% or less, and is calculated from the relative refractive index of the light diffusing fine particles, the average primary particle diameter and the specific gravity. Although it varies depending on the specific surface area per unit mass of the light diffusing fine particles, it is 0.005 to 5.0 g / m ² , preferably 0.01 to 3.0 g / m ² , more preferably 0.03 to 2.0 g. / M ² .

  Next, the xerogel that the light diffusion layer of the present invention has will be described. The light diffusion layer of the present invention holds light diffusion fine particles by xerogel.

  The xerogel referred to in the present invention is a gel that has lost its internal solvent by evaporation or the like and has a network structure with voids, and the porosity of the light diffusion layer in which the light diffusing fine particles are held by the xerogel is 40% or more. Is preferable, and 50% or more is more preferable.

The porosity is defined by the following formula. Here, the void volume V is measured and processed using a mercury porosimeter (measuring instrument name: Autopore II 9220, manufacturer micromeritics instrument corporation), and the cumulative pore volume (ml / g) from 3 nm to 400 nm of the pore radius in the light diffusion layer. Can be obtained as a numerical value per unit area (square meter) by multiplying by the dry solid content (g / square meter) of the light diffusion layer. The coating layer thickness T can be obtained by photographing the cross section of the light diffusion layer with an electron microscope and measuring it.
P = (V / T) × 100 (%)
P: Porosity (%)
V: void volume (ml / m ² )
T: Coating layer thickness (μm)

  The xerogel of the present invention is preferably composed of inorganic fine particles and a resin binder, and more preferably composed of inorganic fine particles having an average primary particle diameter of 18 nm or less and a resin binder. If the average primary particle diameter exceeds 18 nm, the transparency of the light diffusion layer may be reduced, and sufficient transparency and brightness may not be obtained. The inorganic fine particles constituting the xerogel of the present invention preferably have an average secondary particle diameter of secondary aggregated particle diameter of 500 nm or less. When the average secondary particle diameter exceeds 500 nm, the transparency of the light diffusion layer is lowered, and sufficient transparency and luminance may not be obtained. In the case of inorganic fine particles having a secondary agglomerated particle size, the average primary particle size referred to in the present invention can be measured by photography using a transmission electron microscope, and the average secondary particle size is a laser scattering particle size. The number median diameter can be measured using a distribution meter (for example, LA910 manufactured by Horiba, Ltd.).

  Examples of the inorganic fine particles constituting the xerogel include various known fine particles such as amorphous synthetic silica, alumina, alumina hydrate, calcium carbonate, magnesium carbonate, titanium dioxide, but are amorphous because of high porosity. Synthetic silica, alumina or alumina hydrate is preferred.

  Amorphous synthetic silica can be roughly classified into wet method silica, gas phase method silica, and others depending on the production method. Wet method silica is further classified into precipitation method silica, gel method silica, and sol method silica according to the production method. Precipitated silica is produced by reacting sodium silicate and sulfuric acid under alkaline conditions, and the silica particles that have grown are agglomerated and settled, and are then commercialized through the steps of filtration, washing, drying, pulverization and classification. Precipitated silica is commercially available, for example, from Tosoh Silica Co., Ltd. as a nip seal and from Tokuyama Co., Ltd. as a Toxeal. Gel silica is produced by reacting sodium silicate and sulfuric acid under acidic conditions. During aging, the microparticles dissolve and reprecipitate so as to bind the other primary particles, so that the distinct primary particles disappear and form relatively hard aggregated particles having an internal void structure. For example, it is commercially available as nip gel from Tosoh Silica Co., Ltd., and as syloid and silo jet from Grace Japan Co., Ltd. The sol method silica is also called colloidal silica, which is obtained by heating and aging a silica sol obtained through metathesis of sodium silicate acid or the like through an ion exchange resin layer. For example, it is commercially available as Snowtex from Nissan Chemical Industries, Ltd. Yes.

  Vapor phase silica is also called a dry method as opposed to a wet method, and is generally made by a flame hydrolysis method. Specifically, a method of making silicon tetrachloride by burning with hydrogen and oxygen is generally known, but silanes such as methyltrichlorosilane and trichlorosilane can be used alone or in silicon tetrachloride instead of silicon tetrachloride. Can be used in a mixed state. Vapor phase silica is commercially available as Aerosil from Nippon Aerosil Co., Ltd. and QS type from Tokuyama Co., Ltd.

In the present invention, gas phase method silica can be preferably used. The average primary particle diameter of the vapor phase silica used in the present invention is preferably 18 nm or less. In order to obtain higher transparency, the average primary particle diameter is 3 to 15 nm and the specific surface area by the BET method is 200 m. The thing of ² / g or more is used. The average primary particle diameter as used in the present invention is an average particle diameter obtained by measuring the diameter of a circle equal to the projected area of each of the 100 primary particles existing within a certain area by observation with an electron microscope. The BET method referred to in the present invention is one of the powder surface area measurement methods by the vapor phase adsorption method, and is a method for obtaining the total surface area, that is, the specific surface area of a 1 g sample from the adsorption isotherm. Usually, as the adsorbed gas, a large amount of nitrogen gas is used, and the method of measuring the adsorbed amount from the change in pressure or volume of the gas to be adsorbed is most often used. The most prominent expression for expressing the isotherm of multimolecular adsorption is the Brunauer, Emmett, and Teller formula, called the BET formula, which is widely used for determining the surface area. The adsorption amount is obtained based on the BET equation, and the surface area is obtained by multiplying the area occupied by one adsorbed molecule on the surface.

  Vapor phase silica is preferably dispersed in the presence of a cationic compound. Thereby, the light-diffusion layer with a high porosity is obtained, and the effect excellent in visibility is obtained. As a dispersion method, gas phase method silica and a dispersion medium are premixed by ordinary propeller stirring, turbine type stirring, homomixer type stirring, etc., and then a media mill such as a ball mill, a bead mill, a sand grinder, a high pressure homogenizer, an ultrahigh pressure, etc. It is preferable to perform dispersion using a pressure disperser such as a homogenizer, an ultrasonic disperser, a thin film swirl disperser, or the like.

  In the present invention, wet-process silica in which the average secondary particle diameter is pulverized to 500 nm or less can also be preferably used. As the wet method silica used here, precipitation method silica or gel method silica is preferable, and precipitation method silica is particularly preferable. The wet process silica particles used in the present invention are preferably wet process silica particles having an average primary particle diameter of 18 nm or less and an average aggregate particle diameter of 5 to 50 μm, and this is pulverized in the presence of a cationic compound. It is preferable to use the wet process silica fine particles.

  As the alumina used in the present invention, γ-alumina which is a γ-type crystal of aluminum oxide is preferable, and among them, a δ group crystal is preferable. γ-alumina can make primary particles as small as about 10 nm. Usually, secondary particles of thousands to tens of thousands of nanometers are averaged by ultrasonic, high-pressure homogenizer, counter collision type jet crusher, etc. What grind | pulverized the particle diameter to 500 nm or less, Preferably about 20-300 nm can be used.

The alumina hydrate of the present invention is represented by a constitutive formula of Al ₂ O ₃ .nH ₂ O (n = 1 to 3). The alumina hydrate can be obtained by a known production method such as hydrolysis of aluminum alkoxide such as aluminum isopropoxide, neutralization of aluminum salt with alkali, hydrolysis of aluminate and the like.

  The above-mentioned alumina and alumina hydrate used in the invention are used in the form of a dispersion dispersed by a known dispersant such as acetic acid, lactic acid, formic acid, nitric acid and the like.

  Two or more kinds of inorganic fine particles may be used in combination from the inorganic fine particles described above. For example, combined use of pulverized wet method silica and vapor phase method silica, combined use of finely pulverized wet method silica and alumina or alumina hydrate, and combined use of vapor phase method silica and alumina or alumina hydrate. . The ratio in the case of this combined use is preferably in the range of 7: 3 to 3: 7 in any aspect.

  In the present invention, the resin binder used together with the inorganic fine particles constituting the xerogel is not particularly limited, but a hydrophilic resin binder having high transparency is preferably used. For example, polyvinyl alcohol, gelatin, polyethylene oxide, polyvinyl pyrrolidone, polyacrylic acid, polyacrylamide, polyurethane, dextran, dextrin, carrageenan (κ, ι, λ, etc.), agar, pullulan, water-soluble polyvinyl butyral, hydroxyethylcellulose, carboxymethylcellulose Etc. Two or more of these hydrophilic resin binders can be used in combination. A preferred hydrophilic resin binder is completely or partially saponified polyvinyl alcohol or cation-modified polyvinyl alcohol.

  The content of the resin binder constituting the xerogel is preferably 3 to 100% by mass, more preferably 3 to 85% by mass, and further preferably 5 to 70% by mass with respect to the inorganic fine particles constituting the xerogel. . This makes it possible to obtain a high video viewing angle. Moreover, it is preferable that it is 0.1-200 mass% with respect to the inorganic fine particle which comprises xerogel, and, as for the light diffusable fine particle mentioned above, it is especially preferable that it is 0.3-150 mass%.

  For the light diffusion layer, a hardening agent can be used as necessary together with the resin binder. Specific examples of the hardener include aldehyde compounds such as formaldehyde and glutaraldehyde, ketone compounds such as diacetyl and chloropentanedione, bis (2-chloroethyl) urea, 2-hydroxy-4,6-dichloro-1 , 3,5-triazine, a compound having a reactive halogen as described in US Pat. No. 3,288,775, divinyl sulfone, a compound having a reactive olefin as described in US Pat. No. 3,635,718, N-methylol compounds as described in US Pat. No. 2,732,316, isocyanates as described in US Pat. No. 3,103,437, US Pat. No. 3,017,280, US Pat. No. 2,983 Aziridine compounds as described in US Pat. No. 611, carbodiimide compounds as described in US Pat. No. 3,100,704 , Epoxy compounds as described in U.S. Pat. No. 3,091,537, halogen carboxaldehydes such as mucochloric acid, dioxane derivatives such as dihydroxydioxane, chromium alum, zirconium sulfate, borax, boric acid and borates. There exist inorganic crosslinking agents etc., and these can be used 1 type or in combination of 2 or more types.

Dry solid coating amount of the light diffusing layer is preferably in the range of 1 to 50 g / ^{m 2,} more preferably in the range of 3~40g / ^{m 2,} in particular in the range of 5 to 30 g / ^{m 2} is preferred. The light diffusion layer further includes cationic polymers, preservatives, surfactants, colored dyes, colored pigments, UV absorbers, antioxidants, pigment dispersants, antifoaming agents, leveling agents, fluorescent whitening agents, viscosity Stabilizers, pH adjusters and the like can also be added.

  The light diffusion layer may be composed of two or more layers. In this case, the structures of the light diffusion layers may be the same or different from each other. When there are a plurality of light diffusion layers, the light diffusing fine particles can be contained in at least one light diffusion layer.

  In the present invention, various known coating methods can be used as the coating method used for coating the light diffusion layer. Examples include a slide bead method, a slide curtain method, an extrusion method, a slot die method, a gravure roll method, an air knife method, a blade coating method, and a rod bar coating method.

  The light transmissive support of the transmissive screen laminate of the present invention is not particularly limited as long as it has light transmissivity, and is a plate-like one made of glass or plastic, a film-like one, or the like. A layer having a light-transmitting layer such as the above-described light diffusion layer can be used. The type of glass is not particularly limited, but in general, oxide glass such as silicate glass, phosphate glass, and borate glass is practical, especially silicate glass and alkali silicate glass. Silicate glass such as soda lime glass, potassium lime glass, lead glass, barium glass, and borosilicate glass is preferred. As the plastic, for example, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polypropylene, polyethylene, polyarylate, acrylic, acetylcellulose, polyvinyl chloride, etc. can be used. This is preferable because the mechanical strength is improved. The haze value of the light transmissive support is preferably 30% or less.

  The thickness of the light-transmitting support of the present invention can be appropriately selected depending on the material to be applied, but in general, it is preferably 10 μm to 30 mm, more preferably 20 μm to 20 mm.

  The transmissive screen laminate in the present invention has a light diffusing layer containing light diffusing fine particles and xerogel on one surface of a light transmissive support, and is patterned in the form of dots or blocks on the other surface. A transparent pressure-sensitive adhesive layer having discretely arranged adhesive portions and a separate base material are sequentially laminated. In the case of a transmissive screen provided with such a transparent adhesive layer on a light diffusing layer containing light diffusing fine particles and xerogel, the transparent adhesive layer is buried in the light diffusing layer in the manufacturing process and patterned. The light diffusibility changes partially and high transparency cannot be obtained. When using the transmissive screen laminate, the separate substrate is peeled off and the transparent adhesive layer is adhered to the adherend substrate. It is preferable to provide a protective substrate, which will be described later, on the light diffusion layer so that the light diffusion layer is not damaged when a transmission screen is applied to the adherend substrate. In addition, after affixing on a to-be-adhered base material, it is preferable to peel off and use a protection base material.

In the present invention, the adhesive part of the transparent adhesive layer that is patterned in a dotted or block form and arranged discretely is an independent adhesive part over the entire surface of the transparent adhesive layer, and the non-adhesive part is a transparent adhesive. It is continuous over the entire surface of the layer. At this time, the non-adhered portion may be the light-transmitting support surface itself. Furthermore, it is preferable that an area per dot or block-like adhesive part is 1 to 20 mm ² , and an area ratio of the adhesive part in an arbitrary 10 mm square area in the transparent adhesive layer is 5 to 80%. Is preferred. In addition, it is preferable that each adhesion part is uniformly distributed within a 10 mm square area and the whole transparent adhesive layer.

  Since the transparent adhesive layer of the present invention has adhesive portions that are patterned in a dotted or block pattern and are discretely arranged, it is not necessary to perform the water sticking, which is extremely poor in workability, so-called continuous Compared with a general transmission type screen having an adhesive part on the surface, when it is attached to an adherend substrate such as glass or a plastic plate, the air is easily removed and the workability is improved. Furthermore, since no bubbles or the like remain between the adherend substrate, the image does not become unsightly during projector projection. In addition, since the adhesive portions are patterned in a dot shape or a block shape and are provided discretely, the removability is good, so it is easy to peel off or change the sticking position as necessary Yes. In particular, when an ultraviolet curable adhesive resin is used as the adhesive portion, the adhesive durability is good, and therefore, the adhesiveness is hardly reduced even when the adhesive peeling is repeated, and the workability is good.

  In the present invention, the height of the adhesive portions that are patterned in the form of dots or blocks and arranged discretely is preferably 3 μm or more, more preferably 10 μm or more. The upper limit of the height of the bonded portion is not particularly limited, but is preferably 80 μm or less, and more preferably 50 μm or less, from the viewpoint of curling properties and making the transparent adhesive layer inconspicuous when projected from a projector. In addition, the height of the adhesion part in this invention is a difference of the adhesion part vertex in a transparent adhesive layer, and a non-adhesion part surface.

  The thickness of the transparent adhesive layer in the present invention is not particularly limited, and can be appropriately set in consideration of the curl property of the transmission screen laminate.

  The pressure-sensitive adhesive that forms the adhesive portion can be used as long as it has optical transparency. However, the adhesive is applied to a transparent polyethylene terephthalate film having a haze value of 4% defined in JIS K7136 with a thickness of 10 μm. When provided, it is preferable to use an adhesive with a haze value of 10% or less of the laminated film of the polyethylene terephthalate film and the adhesive. In addition to natural adhesives such as rosin, natural rubber and polysaccharides, acrylic adhesives, urethane-based, synthetic rubber-based, and synthetic resin-based thermosetting adhesives such as olefins, main agents and curing agents A two-component pressure-sensitive adhesive that is used as a mixture, a photocurable pressure-sensitive adhesive composed of a photosensitive resin, a photosensitive monomer, a photopolymerization initiator and the like can be used. What is necessary is just to adjust the adhesiveness of an adhesive suitably from a response | compatibility with a to-be-adhered thing. In particular, as an adhesive used for the transparent adhesive layer, an ultraviolet curable adhesive composed of a photosensitive resin, a photosensitive monomer, a photopolymerization initiator, and the like is used. Regardless of the material, it is possible to prevent the transparent adhesive layer from remaining on the transparent material side at the time of peeling, and even when the sticking and peeling are repeated, the workability is improved and the workability is improved. Examples of the ultraviolet curable adhesive include JELCON USL series (manufactured by Jujo Chemical Co., Ltd.).

  Air knife coater, blade coater, bar coater, roll coater, slot nozzle, slot die, screen printing machine, flexographic printing machine, gravure coater, offset gravure coater, hot melt wheel Spiral spray and the like may be mentioned, and selection may be made as appropriate so that the adhesive portions can be arranged in a discrete manner by patterning in a dot shape or block shape, which is an essential item in the present invention. In particular, when an ultraviolet curable adhesive is used as the adhesive used for the transparent adhesive layer, it is preferably provided by patterning by screen printing, and after coating, it is preferably cured by irradiating with ultraviolet rays.

  The separation substrate in the present invention is a film or paper that has been subjected to a release treatment such as silicon resin processing on the surface to be bonded to the transparent adhesive layer so that the transparent adhesive layer does not remain on the separate substrate when peeled off. A well-known base material can be used. The thickness and haze value are not particularly limited since they are finally peeled off, but from the viewpoint of handling, the thickness is preferably 1.0 to 100 μm, more preferably 5.0 to 50 μm.

  It is preferable to provide a protective base material on the surface of the light diffusing layer of the light transmissive support so that the light diffusing layer is not damaged when a transmissive screen is attached to the adherend base material. In addition, a known substrate such as a film or paper having a pressure-sensitive adhesive layer adjusted so that no adhesive remains on the transmissive screen side can be used. In addition, since it peels and uses finally, there is no restriction | limiting in particular also about thickness or a haze value, From a viewpoint of handling, thickness is preferable 1.0-100 micrometers, Furthermore, 5.0-50 micrometers is preferable.

  The surface of the light transmissive support may be subjected to an easy adhesion treatment for the purpose of improving the adhesion between the light diffusion layer and the light transmissive support, or a separate easy adhesion layer may be provided.

  The transmission type screen laminate of the present invention may have a known antireflection layer having a performance of canceling reflected light by utilizing the light interference action by the layer interface on at least one surface. Thereby, the image projected from the projector can be clearly seen. As the antireflection layer, for example, a single layer provided with a highly transparent low refractive index layer such as silicon oxide or lithium fluoride so as to be an optical thin film having a quarter wavelength of the main wavelength, or such A material in which a high refractive index layer such as titanium oxide or zinc oxide is appropriately laminated on a low refractive index layer can be used.

  Furthermore, it is possible to provide a known hard coat layer, diffusion preventing layer or antistatic layer for increasing the strength of the screen on at least one outermost surface.

  The transmissive screen attached to the adherend substrate by the transmissive screen laminate of the present invention can be used by projecting a projector image from either the light diffusion layer side or the opposite side. Further, in general, in the case of a transmissive screen that can be seen through, when light is irradiated in parallel to the normal of the screen, a phenomenon that a direct light from a so-called projector lens, called a hot spot, is unavoidable for a viewer is unavoidable. It is preferable to use a certain angle with respect to the normal.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, the content of this invention is not restricted to an Example. In addition, a part represents the mass part of solid content or a substantial component.

Example 1
On one side of a transparent polyethylene terephthalate film (haze value 4%) having a thickness of 100 μm as a light-transmitting support, a light diffusion layer coating solution 1 having the following composition is applied so that the solid content coating amount is 20.0 g / m ^2. Coating was performed using a slide bead coating device, and hot air at 10 ° C. and 50 ° C. was sequentially blown and dried to provide a light diffusion layer. The aggregated particle-dispersible light diffusing fine particles were used by being previously dispersed with a homomixer using water as a dispersion medium. Moreover, when the void volume was measured using a mercury porosimeter (measuring instrument name: Autopore II 9220, manufacturer micromeritics instrument corporation), the thickness was 19.2 ml / m ² , and the thickness of the light diffusion layer was 34 μm as measured by an electron microscope. The void ratio was 55%.

<Preparation of silica dispersion>
After adding 4 parts of dimethyldiallylammonium chloride homopolymer (molecular weight 9,000) and 100 parts of vapor phase process silica (average primary particle diameter 7 nm, specific surface area 300 m ² / g) to water to prepare a preliminary dispersion, a high pressure homogenizer To prepare a silica dispersion having a solid concentration of 20%. The average secondary particle diameter was 80 nm when measured using LA910 manufactured by Horiba, Ltd.

<Light diffusion layer coating solution 1>
Silica dispersion (as silica solid content) 150 parts Polyvinyl alcohol 100 parts (saponification degree 88%, average polymerization degree 3500)
Boric acid 16 parts Nonionic surfactant 0.3 parts (Polyoxyethylene alkyl ether)
0.7 parts of single particle dispersible light diffusing fine particles (Optobead 500S: manufactured by Nissan Chemical Industries, Ltd., silica, melamine resin composite fine particles (mainly melamine resin), average primary particle size 0.5 μm, true specific gravity 2 .2, Refractive index 1.65)
The total solid content concentration was adjusted with water so as to be 10%.

Subsequently, JELCON USL-101 (manufactured by Jujo Chemical Co., Ltd., having a haze value of 4% and a thickness of 100 μm) is formed on the other surface of the light transmissive support. Adhesive with a haze value of 5% when provided at 10 μm), patterning into dots by screen printing, coating so that the height of the dotted adhesion is 10 μm, and applying ultraviolet rays Irradiated and cured to provide a transparent adhesive layer. In addition, when the transparent adhesion layer was measured using real color confocal microscope OPTELICS C130 (made by Lasertec Co., Ltd.), the area of each dotted adhesive part was 2.0 mm ² , and the transparent adhesion layer The area ratio of the bonded portion in an arbitrary 10 mm square area was 41%, and was uniformly distributed in the 10 mm square area and the entire transparent adhesive layer. Thereafter, the transparent adhesive layer surface was adhered to a high-quality paper having a thickness of 80 μm that had been peeled off by silicon resin processing as a separate substrate to protect the transparent adhesive surface, and the transmission type screen laminate of Example 1 was obtained. In this transmissive screen laminate, the total light transmittance of the transmissive screen before pasting the separate substrate was 87%, and the haze value was 20%.

(Example 2)
On the light diffusion layer of the transmission type screen laminate of Example 1, a transparent polyethylene terephthalate film (hazy value 3%) having a thickness of 16 μm, which has been peeled off with a silicon resin adhesive layer as a protective substrate, is adhered and light-bonded. The transmissive screen laminate of Example 2 was obtained while protecting the diffusion layer surface. In this transmission type screen laminate, the total light transmittance of the transmission type screen before bonding the protective base material and the separate base material was 87%, and the haze value was 20%. The height of the measured spot-like adhesive part is 10 μm, the area of each spot-like adhesive part is 2.0 mm ² , and the area ratio of the adhesive part in any 10 mm square area in the transparent adhesive layer is 41%. Yes, uniformly distributed within a 10 mm square area and throughout the transparent adhesive layer.

(Comparative Example 1)
In the same manner as in Example 1, after the light diffusing layer was provided on the light transmissive support, a transparent adhesive layer was provided on the light diffusing layer so that the height of the dotted adhesive portion was 10 μm. In this transmission type screen laminate, the total light transmittance of the transmission type screen before bonding the separate substrate was 84%, and the haze value was 28%, which was measured in the same manner as in Example 1. The height of the adhesive part is 10 μm, the area of each point-like adhesive part is 2.0 mm ² , and the area ratio of the adhesive part in an arbitrary 10 mm square area in the transparent adhesive layer is 41%, 10 mm square It was uniformly distributed within the area and throughout the transparent adhesive layer.

(Comparative Example 2)
The same as Example 1 except that the light diffusion layer coating solution 1 of Example 1 was changed to the following light diffusion layer coating solution 2 and applied and dried so that the solid content coating amount was 13.2 g / m ^2. Thus, a transmission type screen laminate of Comparative Example 2 was obtained. In this transmission type screen laminate, the total light transmittance of the transmission type screen before pasting the separate substrate was 88%, and the haze value was 20%, which was measured in the same manner as in Example 1. The height of the adhesive part is 10 μm, the area of each point-like adhesive part is 2.0 mm ² , and the area ratio of the adhesive part in an arbitrary 10 mm square area in the transparent adhesive layer is 41%, 10 mm square It was uniformly distributed within the area and throughout the transparent adhesive layer.

<Light diffusion layer coating solution 2>
Alkali-treated gelatin 100 parts Nonionic surfactant 0.3 parts (polyoxyethylene alkyl ether)
0.4 parts of single particle dispersible light diffusing fine particles (Opto beads 500S: manufactured by Nissan Chemical Industries, Ltd., silica, melamine resin composite fine particles (mainly melamine resin), average primary particle size 0.5 μm, true specific gravity 2 .2, Refractive index 1.65)
The total solid content concentration was adjusted with water so as to be 10%.

(Comparative Example 3)
In the same manner as in Comparative Example 2, after providing a light diffusing layer on the light transmissive support, the following transparent adhesive layer solution was applied to the other surface of the light transmissive support so as to have a thickness of 10 μm and dried. A transparent adhesive layer was provided, and a 25 μm thick transparent polyethylene terephthalate film (hazy value 3%) subjected to release treatment by silicon resin processing as a separate substrate was adhered and bonded to protect the transparent adhesive layer. A transmissive screen laminate was obtained. In addition, the area ratio of the adhesive part in an arbitrary 10 mm square area in the transparent adhesive layer is 100%, and in this transmissive screen laminate, the total light transmittance of the transmissive screen before bonding the separate substrate is 86%. The haze value was 22%.

<Transparent adhesive layer solution>
Acrylic copolymer resin 100 parts Crosslinker 4 parts (hexamethylene diisocyanate)
UV absorber 2 parts (2-hydroxy-4-n-octylbenzophenone)
Adjustment was made with toluene so that the total solid content concentration was 30%.

(Comparative Example 4)
In the same manner as in Example 1, after providing the light diffusing layer on the light transmissive support, the transparent adhesive layer solution used in Comparative Example 3 was formed to have a thickness of 10 μm on the other surface of the light transmissive support. A transparent adhesive layer is formed by applying and drying to a transparent polyethylene terephthalate film (having a haze value of 3%) having a thickness of 25 μm, which has been subjected to a release treatment by silicon resin processing as a separate substrate, to protect the transparent adhesive layer, A transmission type screen laminate of Comparative Example 4 was obtained. In addition, the area ratio of the adhesive part in an arbitrary 10 mm square area in the transparent adhesive layer is 100%, and in this transmissive screen laminate, the total light transmittance of the transmissive screen before bonding the separate substrate is 86%. The haze value was 22%.

(Comparative Example 5)
A transparent polyethylene terephthalate film (hazy value 3%) having a thickness of 16 μm, which has been peeled off with a silicon resin adhesive layer as a protective substrate, is adhered and bonded onto the light diffusion layer of the transmission type screen laminate of Comparative Example 4. The transmissive screen laminate of Comparative Example 5 was obtained while protecting the diffusion layer surface. In addition, the area ratio of the adhesive part in an arbitrary 10 mm square area in the transparent adhesive layer is 100%, and in this transmissive screen laminate, the total light rays of the transmissive screen before bonding the protect substrate and the separate substrate are combined. The transmittance was 86% and the haze value was 22%.

  The following evaluation was implemented regarding the obtained transmission type screen laminated body of Examples 1 and 2 and Comparative Examples 1-5. The obtained results are shown in Table 1.

<Ease of pasting the screen>
The 3 mm-thick transparent glass surface as the adherend substrate and the transparent adhesive layer surface of the transmission screen from which the A4 size separate substrate was peeled were bonded together.
The ease of attaching the screen at that time was evaluated according to the following criteria.
○: Air was easily removed and the screen could be easily pasted. △: Air was slightly difficult to escape and it took some time to attach the screen. ×: Air was not completely removed, making it impossible to attach the screen. , I had to cope with water paste with poor workability for pasting

<Ease of screen peeling>
A4 size transmissive screen affixed to a 3 mm thick transparent glass surface as a substrate to be adhered (the separation substrate was peeled off, Comparative Examples 3 to 5 were affixed with water, and the others were affixed as they were) The ease of peeling when peeling from the adherend substrate was evaluated according to the following criteria.
○: A large force is not required for peeling, and it can be easily peeled off, and the transparent adhesive layer did not remain on the transparent acrylic plate. Δ: A relatively large force was required for the peeling above the ○ level, but it was transparent. The transparent adhesive layer did not remain on the acrylic plate x: A force greater than the above Δ level was required for peeling, and a part of the transparent adhesive layer remained on the transparent acrylic plate, and it took a very long time to remove them.

<Screen transparency>
A2 size transmission screen affixed to a transparent acrylic plate with a thickness of 5 mm as the substrate to be adhered (separate the separation substrate, paste the comparative examples 3 to 5 with water, and paste the others as they were) In this regard, those having a protective base material were peeled off and then visually evaluated for transparency according to the following criteria.
○: Transparent, transparent adhesive layer pattern is difficult to understand, and very transparent. Δ: Slightly low transparency, transparent adhesive layer pattern can be confirmed, and slightly transparent. ×: Transparency is extremely low, clearly The coating pattern of the transparent adhesive layer can be confirmed and the transparency is low

<Visibility of video>
A2 size transmission screen affixed to a transparent acrylic plate with a thickness of 5 mm as the substrate to be adhered (separate the separation substrate, paste the comparative examples 3 to 5 with water, and paste the others as they were) In the case of a projector having a protective substrate, after peeling it off, it stands upright and actually projects an image from a transmissive screen side with a digital projector (MP515ST, manufactured by BenQ), and a transmissive screen from the opposite side of the projector. The image projected on was observed and evaluated visually according to the following criteria. The projector was irradiated with an angle of about 30 degrees from the upper direction with respect to the vertical line of the screen, and the evaluator visually evaluated the image at a position parallel to the screen.
◎: Image brightness is extremely high and visibility is very good ○: Image brightness is high and visibility is good △: Image visibility is not the above ○ level but acceptable level ×: Image brightness is low and visibility Is bad

  From the results in Table 1, the transmissive screen laminate of the present invention is excellent in high transparency and visibility of the image projected from the projector, and is attached or adhered to a substrate to be bonded such as glass or a plastic plate. It can be seen that a see-through transmissive screen laminate having good workability when peeling from the substrate can be obtained. In Comparative Example 4 where the protective base material was not provided, fine scratches were generated in the light diffusion layer when water was applied, and in Comparative Example 5, no damage was generated in the light diffusion layer due to the protective base material. On the other hand, in Example 1 in which the protective base material of the present invention was not provided, the light diffusion layer was not damaged at all as in Example 2 in which the protective base material was provided.

DESCRIPTION OF SYMBOLS 1 Transmission type screen laminated body 2 Light diffusible fine particle 3 Light diffusing layer 4 Light transmissive support body 5 Xerogel 6 Adhesion part 7 patterned in the shape of dots or blocks and arranged discretely 8 Separate base material 8 Transparent adhesive layer 10 Adhesive base material 100 Transmission type screen

Claims (1)

A laminated body for use in a see-through transmissive screen having a light diffusing layer on one surface of a light transmissive support and a transparent adhesive layer and a separate substrate sequentially laminated on the other surface. The diffusion layer contains light diffusing fine particles and xerogel, the light diffusing fine particles are supported on the xerogel, and the transparent adhesive layer has adhesive portions that are discretely arranged in a pattern of dots or blocks. A laminate used for a transmissive screen that can be seen through.