WO2021187556A1

WO2021187556A1 - Optical film laminate, and polarizing plate laminate and display that use same

Info

Publication number: WO2021187556A1
Application number: PCT/JP2021/011057
Authority: WO
Inventors: 杉山　仁英
Original assignee: 株式会社巴川製紙所
Priority date: 2020-03-19
Filing date: 2021-03-18
Publication date: 2021-09-23
Also published as: JPWO2021187556A1; CN115335735A

Abstract

The present invention provides an optical film laminate capable of suppressing reduction in viewability and occurrence of blurring of a screen while a display is on, and making a white or light-colored peripheral material of the display seamless. This optical film laminate is an optical film laminate for a display and used while laminated directly or indirectly on a polarizing plate (A). The display includes a display panel device, the polarizing plate (A) is laminated directly or via another layer (b) on the viewing side from the display panel device, a reflective polarizer layer and a diffusion element layer are laminated directly or via another layer (a), the diffusion element layer is disposed on the viewing side from the reflective polarizer layer, the optical film laminate is laminated directly or via another layer (c) on the viewing side from the polarizing plate (A), the optical film laminate is disposed such that the transmission axis of the polarizing plate (A) and the transmission axis of the reflective polarizer layer have a relationship of 0±30° or 180±30°, and the reflective polarizer layer reflects polarized light orthogonal to the transmission axis of the polarizing plate (A).

Description

Optical film laminate and polarizing plate laminate and display using it

Regarding an optical film laminate, a polarizing plate laminate using the same, and a display.

Thin displays such as conventional liquid crystal displays and organic EL displays have been used in various modes with their widespread use.
In recent years, the collective unit panel, which is the main part of the instrument panel in automobiles, that is, a part of the display system of the meter cluster panel or the entire panel has been made into a thin display, and the center information display (CID) has been made into a thin display. Product development is progressing.
Black (dark) interiors are mainly used for the interior of automobiles to prevent diplomatic reflection, but from the viewpoint of design, the front plate, which is the outermost surface of the image display part of the thin display, and the periphery of the front plate Seamless (neutral gray) is used to make it difficult to see the boundary with the material (interior, etc.) and to recognize the existence of the front panel. For the interior of an automobile having a black color scheme, the front plate of the thin display is corrected with black to make the boundary of the thin display inconspicuous (Patent Document 1).

In addition, the number of cases where thin displays are embedded in various home appliances other than TVs and monitors is increasing, and in the future, cases where thin displays are embedded in furniture, walls, floors, ceilings, etc. of buildings will increase. Is expected. Home appliances, furniture, walls, floors, ceilings, etc. of buildings are not limited to black (dark) colors, but there are many designs with white or light colors.
Also, in automobiles, as the development of autonomous driving technology progresses, various studies are being conducted on how to use the space inside the vehicle. Among them, it is mentioned that as the ratio of driving by people decreases, the interior space of the car may become a space like a living room in a house, and the interior color of the car is the wall, floor, ceiling, etc. in the house. The use of bright colors such as white and light colors is being considered.

Japanese Unexamined Patent Publication No. 2000-265133

The seamlessness proposed in Patent Document 1 is performed by adjusting the color of the front plate of the thin display with a black pigment or dye, so that the transmittance of light emitted from the thin display is reduced and the display is lit. The visibility of the time is reduced. Therefore, it is necessary to take measures such as increasing the backlight output of the display to ensure visibility.

In addition, when embedding or arranging a liquid crystal display or an organic EL display in an environment using white or light colors in an automobile or a house, the front plate surface of these conventional displays is black when the lights are turned off. It is difficult to make it seamless with the surrounding materials. Similar to the invention of Patent Document 1, when the color tone of the front plate is adjusted with a white pigment or dye as in the case of seamless black color, the transmittance of the light emitted from the display is lowered and the light is lit. There is also a problem that the visibility is lowered. In addition, whitening enhances the diffusivity and reflectivity of light in the display, which causes a problem that the image is blurred.

Therefore, the present invention is an optical film laminate capable of suppressing a decrease in visibility when the display is lit and causing blurring of the screen, and making it seamless with respect to the peripheral material of the display in which a white or light color is used. The purpose is to provide.

In order to solve the above problems, the optical film laminate of the present invention is characterized by having a reflective polarizer layer and a diffusing element layer, and is characterized in that it is used for a display. That is, the present invention is as follows.
The present invention (1)
An optical film laminate for a display used by being directly or indirectly laminated with a polarizing plate (A).
The display includes a display panel device.
The polarizing plate (A) is laminated on the visual side of the display panel device directly or via another layer (b).
In the optical film laminate, the reflective polarizer layer and the diffusing element layer are laminated directly or via another layer (a).
The diffuser layer is arranged on the visual side of the reflective polarizer layer.
The optical film laminate is laminated directly on the visible side of the polarizing plate (A) or via another layer (c).
The optical film laminate is arranged so that the transmission axis of the polarizing plate (A) and the transmission axis of the reflection polarizer layer have a relationship of 0 ± 30 ° or 180 ± 30 °.
The reflective polarizer layer is an optical film laminate characterized by reflecting polarized light orthogonal to the transmission axis of the polarizing plate (A).
The present invention (2)
The reflective polarizer layer includes a first polymer layer and a second polymer layer.
The optical film laminate according to the invention (1), wherein either the first polymer layer or the second polymer layer is a naphthalate-based polymer.
The present invention (3)
The diffusion element layer is any one of a diffusion film in which fine particles are dispersed, a diffusion pressure-sensitive adhesive layer in which fine particles are dispersed, a non-woven fabric, a diffusion film having irregularities on the surface, and a porous film. The optical film laminate according to the invention (1) or (2).
The present invention (4)
The optical film according to any one of the inventions (1) to (3), wherein the haze of the diffusing element layer is 40% or more and 95% or less, and the total light transmittance is 30% or more and 88% or less. It is a laminated body.
The present invention (5)
The optical film laminate is
The transmitted light (T1) emitted from the light of the C light source incident from the reflection polarizer layer side of the optical film laminate through the optical film laminate on the diffuser layer side of the optical film laminate is emitted from JIS Z8722: After measuring in a 2 ° field according to the 2009 standard, the transmitted Y value calculated by the C light source is 20 or more and 50 or less.
The light of the C light source incident from the diffuser element layer side of the optical film laminate is reflected by the reflection polarizer of the optical film laminate, and the reflected light (reflected light) emitted through the optical film laminate to the diffuser layer side. The inventions (1) to (4), wherein R1) is measured in a 2 ° field according to the JIS Z8722: 2009 standard, and then the reflected Y value calculated by the C light source is 40 or more and 80 or less. It is one of the optical film laminates of.
The present invention (6)
The optical film laminate is characterized by having a whiteness WI value of 45 or more and 90 or less in a specular reflection light removal method (SCE) of a D65 light source in a spectrocolorimeter according to the ASTM E313-73 standard. The optical film laminate according to any one of the inventions (1) to (5).
The present invention (7)
A polarizing plate laminate containing the optical film laminate according to any one of the inventions (1) to (6) and the polarizing plate (A).
The polarizing plate (A) is laminated on the reflective polarizer layer of the optical film laminate on the side opposite to the diffuser element layer of the optical film laminate, either directly or via another layer (d).
The transmission axis of the polarizing plate (A) and the transmission axis of the reflective polarizer layer of the optical film laminate are arranged so as to be in a direction of 0 ± 30 ° or 180 ± 30 °. It is a polarizing plate laminate.
The present invention (8)
The polarizing plate laminate is
The transmitted light (T2) emitted from the light of the C light source incident from the polarizing plate side of the polarizing plate laminate through the polarizing plate laminate on the diffusion element layer side of the polarizing plate laminate is according to JIS Z8722: 2009 standard. The transmitted Y value calculated by the C light source after measuring in the 2 ° field according to the above is 15 or more and 40 or less.
The light of the C light source incident from the diffuser element layer side of the polarizing plate laminate is reflected by the reflective polarizer of the polarizing plate laminate, and the reflected light emitted through the polarizing plate laminate side to the diffuser layer side ( R2) is measured in a 2 ° field according to the JIS Z8722: 2009 standard, and then the reflected Y value calculated by the C light source is 40 or more and 80 or less. The body.
The present invention (9)
A display (D1) having a laminated structure including a display panel device, a polarizing plate (A) on the visual side of the display panel device, and an optical film laminate according to any one of claims 1 to 6. hand,
The polarizing plate (A) is laminated directly on the visible side of the display panel device or via another layer (b).
The optical film laminate is laminated directly or via another layer (a) on the viewing side of the polarizing plate (A) so that the diffusion element layer is on the viewing side of the reflective polarizer layer. ,
The optical film laminate is arranged so that the transmission axis of the polarizing plate (A) and the transmission axis of the reflection polarizer layer are oriented in a direction of 0 ± 30 ° or 180 ± 30 °.
The reflection polarizer layer is a display characterized by reflecting polarized light orthogonal to the transmission axis of the polarizing plate (A).
The present invention (10)
A display (D2) having a laminated structure, which includes a display panel device and does not include a polarizing plate on the visual side of the display panel device.
The display (D2) includes the polarizing plate laminate of the invention (7) or (8).
The polarizing plate laminate is laminated directly on the visible side of the display panel device or via another layer (c).
The polarizing plate laminate is a display characterized in that the reflective polarizing element layer of the polarizing plate laminate is arranged so as to be on the visual side of the polarizing plate (A) of the polarizing plate laminate. ..

According to the present invention, with respect to a display having a liquid crystal panel or an organic EL panel and having a polarizing plate on the visual side of the liquid crystal panel or the organic EL panel, deterioration of visibility when the display is lit and occurrence of screen blur are suppressed. It is possible to provide an optical film laminate that can be made seamless with respect to a peripheral material of a display in which a white or light color is used.

FIG. 1 is a schematic view illustrating an example of arrangement of the optical film laminate of the present invention and the laminated structure of the display when the display includes the polarizing plate (A). FIG. 2 is a schematic view illustrating an example of an arrangement of a polarizing plate laminate including the optical film laminate of the present invention and a laminated structure of the display when the display does not include the polarizing plate (A). FIG. 3 is a schematic view illustrating the measurement of the Y value of the optical film laminate of the present invention. FIG. 4 is a schematic view illustrating the measurement of the Y value of the polarizing plate laminate of the present invention.

In the present invention, when the compound name is simply indicated, all isomers thereof are included.

In the present invention, the display panel device refers to a drive panel for displaying images such as a liquid crystal display panel, an organic EL panel, and a micro LED panel.
Further, in the present invention, the drive panel of the liquid crystal display panel means a device including elements necessary for display such as a liquid crystal cell, a backlight, and a color filter, and in the present invention, the display panel device is on the visual side. It shall include the presence or absence of the polarizing plate.
Furthermore, the drive panel is a panel such as a liquid crystal cell that controls the polarization of the liquid crystal to transmit and block light (opening and closing the shutter), and a light emitting element such as an organic EL panel and a micro LED panel. Is turned ON / OFF to form an image.

A liquid crystal cell is a cell in which liquid crystal molecules are sandwiched between two glass substrates incorporating a transparent electrode, or a cell in which a color filter is further included, and includes an optical film such as a light source and a polarizing plate. Make it not exist.
An organic EL panel is a negative electrode such as metal / electron injection layer / electron transport layer / light emitting layer / hole transport layer / hole injection layer / positive electrode such as ITO, and a substrate such as a glass plate or a transparent plastic plate. Therefore, optical films such as polarizing plates and color filters are not included. Generally, a polarizing plate is not used in the organic EL display, but some organic EL displays are provided with a polarizing plate on the visual side of the organic EL panel in order to prevent internal reflection.
The micro LED panel refers to a substrate on which a micro LED is configured, and a polarizing plate may be used for the purpose of preventing internal reflection or the like.

In the present invention, the viewing side means the side of the display close to the viewer. Therefore, when it is the viewing side of the display panel device, the direction of the viewing panel device is indicated.

<<< Optical film laminate >>>
The optical film laminate of the present invention includes a reflective polarizer layer and a diffusing element layer. The reflective polarizer layer and the diffusing element layer are laminated directly or via another layer (a).

The optical film laminate of the present invention is used by being directly or indirectly laminated with a polarizing plate (A) arranged to face the visual side of a display panel device included in a display (see FIGS. 1 and 2). ).

The optical film laminate of the present invention is used so that the diffusion element layer of the optical film laminate is arranged on the visual side of the reflection polarization element of the optical film laminate (FIG. 1 or 2).

The optical film laminate of the present invention is laminated on the viewing side of the polarizing plate (A) directly with the polarizing plate (A) or via another layer (b) (see FIGS. 1 and 2).

The optical film laminate of the present invention is arranged so that the transmission axis of the polarizing plate (A) and the transmission axis of the reflection polarizer layer of the optical film laminate are in a relationship of 0 ± 30 ° or 180 ± 30 °.

The reflective polarizer layer of the optical film laminate of the present invention reflects polarized light orthogonal to the transmission axis of the polarizing plate (A).

The thickness of the optical film laminate is not particularly limited as long as the effect of the present invention is not impaired, but can be, for example, 10 to 200 μm, preferably 10 to 150 μm, more preferably 15 from the viewpoint of thinning. It is ~ 100 μm.

<< Structure of optical film laminate >>
<Reflective polarizer layer>
The reflection polarizer layer has a function of separating the emitted light from the liquid crystal panel or the organic EL panel into transmitted polarized light and reflected polarized light. The reflected polarizing element layer according to the present invention is a layer that transmits linearly polarized light in one vibration direction and reflects linearly polarized light in at least one other vibration direction.

In the reflective polarizer layer according to the present invention, when the optical film laminate of the present invention described later is used for a display, the transmission axis of the reflection polarizer layer and the transmission axis of the polarizing plate (A) are 0 ± 30 ° or It is arranged so as to be in the direction of 180 ± 30 °. At that time, the reflective polarizer layer reflects polarized light orthogonal to the transmission axis of the polarizing plate (A). Further, it is more effective when the transmission axis of the reflection polarizer layer and the transmission axis of the polarizing plate (A) are 0 ° or 180 °, but the transmission axis of the reflection polarizer layer and the polarizing plate (A) are more effective. ) Is within the range of 0 ° or 180 ° to ± 30 °, the seamlessness between the display and the white or light-colored display peripheral member can be easily adjusted. can.

As the reflective polarizing element layer, known ones can be used and are not particularly limited as long as the effects of the present invention are not impaired. The reflective polarizer layer includes, for example, two types of resins (for example, polyethylene naphthalate as the first polymer layer and a second polymer layer) having different refractive indexes in the stretching direction when stretched as the reflective polarizer layer (1). Polyethylene naphthalate copolymer as a polymer layer) is alternately laminated by an extrusion molding technique, and the layers are stretched (specifically, DBEF manufactured by 3M Co., Ltd.). (Refer to the publication, etc.);
As the reflective polarizer layer (2), a cholesteric liquid crystal polymer layer and a 1/4 wave plate are laminated, and light incident from the cholesteric liquid crystal polymer layer side is separated into two circularly polarized lights in opposite directions, and one of them is separated. Those that transmit, reflect the other, and convert the transmitted circularly polarized light into linearly polarized light by a 1/4 wave plate (specifically, Nipox manufactured by Nitto Denko, Tranmax manufactured by Merck, etc. (Refer to the Gazette, etc.);
As the reflective polarizer layer (3), a metal lattice reflective polarized light (see US Pat. No. 6,288,840, etc.) in which the metal is finely processed to emit reflected polarized light even in the visible light region, and metal fine particles are polymerized. A film added and stretched in a matrix (see JP-A-8-184701, etc.), a resin film in which a wire grid is formed with metal nanowires (specifically, WGF manufactured by Asahi Kasei Co., Ltd., JP-A-2017). -173832 (see, etc.)) and the like; Of these, the reflective polarizer layer (1) is preferably used because of its excellent productivity and workability. On the other hand, when heat resistance is required, the reflective polarizer layer (3) is preferably used.

Here, the reflective polarizer layer (1) includes at least a first polymer layer and a second polymer layer.

The materials of the first polymer layer and the second polymer layer are not particularly limited as long as the effects of the present application are not impaired, but the first polymer is easily molecularly oriented when the polymer is stretched, and from the viewpoint of productivity. It is desirable that either the layer or the second polymer layer is a naphthalate polymer. Further, both the first polymer layer and the second polymer layer may be naphthalate-based polymers. Here, the naphthalate-based polymer means a polymer containing a naphthalate functional group in its molecular structure.

The naphthalate polymer can be obtained by polymerizing this naphthalate monomer. The naphthalate-based monomer that can be used to form the naphthalate-based polymer is not particularly limited as long as the effect of the present invention is not impaired, and is, for example, 2,6-, 1,4-, 1,5-2. , 7- and 2,3-naphthalene dicarboxylic acids and other naphthalates and esters thereof.

Naphthalate-based monomers can form polyesters by polymerizing the monomers with diols such as alkane glycol and cycloalcan glycol, 2,6-, 1,4-, 1,5-, 2,7-. And / or polyethylene naphthalate, which is a copolymer of 2,3-naphthalene-dicarboxylic acid and ethylene glycol.

It can also be a copolymer of 2,6-, 1,4-, 1,5-, 2,7- or 2,3-naphthalene-dicarboxylic acid, terephthalic acid, and ethylene glycol. This copolymer is generally called coPEN.

The thickness of the first polymer layer and the second polymer layer is not particularly limited. A plurality of laminated layers of the first polymer layer and the second polymer layer are further laminated and stretched to obtain a reflective polarizer layer having a desired thickness, so that the first polymer layer and the second polymer layer in the reflective polarizer layer are obtained. The thickness of the polymer in is difficult to measure. The laminated product of the first polymer layer and the second polymer layer is generally laminated up to about 100 layers. The thickness of the reflective polarizing element layer can be 10 to 100 μm, preferably 10 to 50 μm from the viewpoint of thinning, and more preferably 10 to 30 μm.

The total light transmittance of the reflected polarizing element layer is not particularly limited as long as the effect of the present invention is not impaired. The total light transmittance of the reflective polarizer layer can be, for example, 30% or more and 70% or less, preferably 40% or more and 60% or less, and when the total light transmittance is in the range, from the display. A high degree of whiteness can be obtained without reducing the emitted light of. That is, it is possible to obtain a display that has excellent visibility and can be made seamless with respect to the peripheral material of the display in which a white or light color is used.

The total light transmittance of the reflective polarizer layer can be measured by the method described in JIS K7361-1: 1997 "Plastic-Transparent Material Total Light Transmittance Test Method". However, since the light source of the measuring instrument is not a little polarized, it should be calculated by averaging the values measured in the predetermined arrangement and the values measured in the arrangement rotated 90 ° with respect to the measuring instrument. Therefore, since it is possible to obtain a measured value that is not affected by the polarization of the light source, in the present invention, the average value of these two total light transmittances is shown as the total light transmittance.

<Diffusing element layer>
The diffusing element layer is a layer having a function of diffusing the transmitted light. The diffusing element layer is not particularly limited as long as the effect of the present invention is not impaired.

The thickness of the diffusing element layer is not particularly limited as long as the effect of the present invention is not impaired, but can be 1 to 100 μm, preferably 15 to 50 μm.

As a diffusing element layer,
As the diffusing element layer (1), fine particles are dispersed in a material having translucency (transparent or translucent property in the present invention) such as an adhesive, an adhesive, a resin, glass, and a non-woven fabric;
As the diffusing element layer (2), one having an uneven structure by processing the surface of a translucent material such as resin or glass;
The diffusion element layer (3) has a porous structure inside a translucent material such as resin, glass, or non-woven fabric;
Diffusing element layer (4) having a plurality of through holes or non-penetrating holes extending from one surface of a translucent material such as resin, glass, or non-woven fabric to the other surface;
As the diffusing element layer (5), a plurality of regions having different refractive indexes (for example, a columnar region) are formed inside a translucent resin;
Can be mentioned. These can be used alone or in combination of two or more. It should be noted that a certain layer (for example, a non-woven fabric) is a plurality of diffusing element layers, such as a material in which fine particles of the diffusing element layer (1) are dispersed and a non-woven fabric of the diffusing element layer (3) and the diffusing element layer (4). May be applicable as.

The diffusion element layer (1) is a base material such as an adhesive, an adhesive, a resin, glass, or a non-woven fabric in which fine particles having a refractive index different from that of the base material are dispersed. These can be appropriately combined in consideration of the required light diffusivity performance. Here, the light diffusivity performance indicates the light diffusivity derived from the difference in the light transmittance and the refractive index between the base material and the fine particles.

Considering the required light diffusivity performance, the amount of fine particles added is 40% or more and 95% or less in haze when used as a diffusing element layer, and 30% or more and 88% or less in total light transmittance. If this is the case, it can be appropriately selected, but as an example, when the entire diffusion element layer is 100% by mass, it can be 10.0 to 50.0% by mass.

As the material of the base material of the diffusion element layer (1), for example, acrylic pressure-sensitive adhesive; silicone pressure-sensitive adhesive; urethane pressure-sensitive adhesive; rubber-based pressure-sensitive adhesive; epoxy adhesive; olefin adhesive; polycarbonate resin; (meth) acrylic resin; Polystyrene resin; polyolefin resin; polyester resin such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, terebutylene terephthalate; various glasses; non-woven fabric made of glass fiber, non-woven fabric made of polyolefin resin fiber such as polypropylene fiber; and the like.

The material of the fine particles of the diffusing element layer (1) is not limited to the side as long as the effect of the present invention is not impaired, and for example, silica, calcium carbonate, aluminum hydroxide, magnesium hydroxide, clay, talc, titanium dioxide and the like. Inorganic white pigments; silicone resin, acrylic resin, polystyrene resin, styrene-acrylic copolymer resin, polyethylene resin, epoxy resin and other resin fine particles having a refractive index different from that of the pressure-sensitive adhesive can be mentioned. These can be used alone or in combination of two or more.

The average particle size of the fine particles can be appropriately selected as long as the haze of the diffusing element layer is 40% or more and 95% or less and the total light transmittance is 30% or more and 88% or less. As, 0.1 to 50 μm can be mentioned. The average particle size of the fine particles can be measured by a particle counter.

The diffusion element layer (2) has an uneven structure by processing the surface of a translucent material such as resin or glass.

The material of the diffusing element layer (2) is not particularly limited as long as the effect of the present invention is not impaired, and for example, polycarbonate resin; acrylic resin; polystyrene resin; polyolefin resin; polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, and the like. Polyethylene resin such as terebutylene terephthalate; various types of glass and the like can be mentioned.

Here, the uneven structure may have concave and / or convex portions on the surface, and its shape, size, quantity, distribution, distribution density, and regularity of distribution are not particularly limited.

The uneven structure includes, for example, a groove structure having a semicircular cross section, a polygonal shape, a corrugated shape, or the like; a concave dot structure having a hemispherical shape, a conical shape, a cylindrical shape, a polygonal weight shape, a polygonal column shape, a lens shape, or the like. A convex dot structure can be mentioned. These can be used alone or in combination of two or more.

The size of the uneven structure can be appropriately selected as long as the haze of the diffusing element layer is 40% or more and 95% or less and the total light transmittance is 30% or more and 88% or less. When the uneven structure is a groove structure, the average width of the groove is 0.1 to 50 μm, and when the uneven structure is a dot structure, the average value of the longest length in the cross section of the dot structure on the surface of the diffusion element layer (dots). The average length of the structure) can be 0.1 to 50 μm. For the average width of the groove structure and the average length of the uneven structure, 20 groove structures or uneven structures are randomly selected, a scanning electron microscope image is taken, the length is measured, and the average of 20 is calculated. It can be obtained by doing.

The diffusion element layer (3) has a porous structure inside a translucent material such as resin, glass, or non-woven fabric. The resin or glass can be formed into a porous structure by forming bubbles inside by heating and melting the resin or glass and then solidifying the resin or glass while inflowing gas. The porous structure may be an independent hole (independent hole), a communication structure in which independent holes are connected, or a combination of these. Further, the porous structure may reach the surface of the diffusion element layer. The non-woven fabric is an aggregate of fibers without weaving them, and the voids between the fibers can be regarded as a porous structure.

When resin or glass is used, the average diameter of the independent holes forming the porous structure or the individual holes forming the communicating structure is 40% or more and 95% or less in the haze when the diffusing element layer is used, and the total light beam. If the transmittance is 30% or more and 88% or less, it can be appropriately selected, and as an example, 0.1 to 500 μm can be mentioned. For the average diameter of the individual holes forming the independent holes or the communicating structure, 20 individual holes forming the independent holes or the communicating structure are randomly selected from the cross section of the resin or glass having the porous structure. , It can be obtained by taking an image with a scanning microscope, measuring the diameter thereof, and calculating the average of 20 pieces.

Even when a non-woven fabric is used, it can be appropriately selected as long as the haze when used as the diffusing element layer is 40% or more and 95% or less and the total light transmittance is 30% or more and 88% or less. As an example, a non-woven fabric having a fiber diameter of 3 to 20 μm and a fiber length of 0.1 to 2 mm produced by wet papermaking and having a grain size of 5 to 30 g / m ^{2 or less can be mentioned.}

The material of the diffusing element layer (3) is not particularly limited as long as the effect of the present invention is not impaired, and for example, polycarbonate resin; (meth) acrylic resin; polystyrene resin; polyolefin resin; polyethylene terephthalate, polyethylene naphthalate, poly. Polybutylene terephthalate, terebutylene terephthalate and other polyester resins; various glasses; glass fiber non-woven fabrics, polyolefin resin fiber non-woven fabrics such as polypropylene fibers; and the like can be mentioned.

The diffusion element layer (4) has a plurality of through holes or non-penetrating holes extending from one surface of a translucent material such as resin, glass, or non-woven fabric to the other surface. Further, in the non-woven fabric, voids communicate with each other from one surface to the other surface. That is, the voids of the non-woven fabric can be treated as through holes, but the through holes in the diffusion element layer (4) mean that the non-woven fabric is formed by processing through holes different from the voids of the non-woven fabric.

The shape of the through hole and the hole that does not penetrate is not particularly limited, and the cross-sectional shape on the surface of the diffusion element layer may be any of a circular shape, an elliptical shape, a polygonal shape, and the like. The average diameter of the through hole and the non-penetrating hole is appropriately selected as long as the haze of the diffusing element layer is 40% or more and 95% or less and the total light transmittance is 30% or more and 88% or less. However, as an example, 0.1 to 50 μm can be mentioned. For the average diameter of the through hole and the non-penetrating hole, 20 through holes and the non-penetrating hole were randomly selected, photographed with a scanning microscope, and the diameter was measured to obtain the average of 20 holes. It can be obtained by calculating. As for the non-woven fabric, as described above, the size of the through hole as a void is not measured, but only the through hole produced by processing or the like is measured.

The material of the diffusing element layer (4) is not particularly limited as long as the effect of the present invention is not impaired, and for example, polycarbonate resin; (meth) acrylic resin; polystyrene resin; polyolefin resin; polyethylene terephthalate, polyethylene naphthalate, poly. Polybutylene terephthalate, terebutylene terephthalate and other polyester resins; various glasses; glass fiber non-woven fabrics, polyolefin resin fiber non-woven fabrics such as polypropylene fibers; and the like can be mentioned.

The through hole and the non-penetrating hole of the diffusion element layer (4) can be formed by a known method such as a laser processing method.

Examples of the diffusing element layer (5) include those in which a plurality of regions having different refractive indexes (for example, a columnar region) are formed inside the resin. These can be used alone or in combination of two or more. As such a diffusion element layer (5), for example, one disclosed in International Publication WO2015 / 111523 as having a pillar structure, and one disclosed in Japanese Patent Application Laid-Open No. 2015-12789 as having a louver structure. Can be used.

Among these diffusion element layers (1) to (5), a diffusion film in which fine particles are dispersed, a diffusion adhesive layer in which fine particles are dispersed, a non-woven fabric in which fine particles are dispersed, a diffusion film having irregularities on the surface, and a porous film. , Is preferable from the viewpoint of productivity and cost.

These diffusing element layers (1) to (5) can be colored with a pigment or dye of white or other colors. By doing so, it is possible to easily adjust the seamlessness between the display and the white or light-colored display peripheral member.

The haze of the diffusing element layer is not particularly limited as long as the effect of the present invention is not impaired, but 40% or more and 95% or less is preferable, 50% or more and 94% or less is more preferable, and 80% or more and 92% or less. It is more suitable. When the haze is in the range, the diffusivity and the reflectivity are increased, so that the whiteness is increased and the image on the display can be made clearer. The haze of the diffusing element layer is obtained by the method described in JIS K7136: 2000 "Plastic-How to obtain haze of transparent material".

The total light transmittance of the diffusing element layer is not particularly limited as long as the effect of the present invention is not impaired, but is preferably 30% or more and 88% or less, more preferably 40% or more and 80% or less, and 50% or more. 70% or less is more preferable. When the total light transmittance is in the range, the sharpness of the image on the display is high, and the whiteness is high because of the excellent diffusivity and reflectivity, and seamlessness can be realized.

<Other layer (a)>
The optical film laminate of the present invention can include another layer (a). The reflective polarizer layer and the diffusing element layer may be laminated via another layer (a).

The other layer (a) is not particularly limited, but is an adhesive layer; an adhesive layer; a void layer, a retardation film, a color filter, a layer on which a pattern or pattern is printed, a film containing the printing, or the like. Can be used. Here, the void layer indicates voids at regular intervals. In addition, the other layer (a) can be colored with a white or other color pigment or dye. By doing so, it is possible to easily adjust the seamlessness between the display and the white or light-colored display peripheral member. In addition, it is possible to easily adjust the seamlessness with the display peripheral members by the pattern or pattern.

<Outermost layer on the visual side>
When the optical film laminate is used for a display, the outermost surface layer may be used on the outermost surface on the visual side, that is, on the surface of the diffusion element layer of the optical film laminate.

The outermost surface layer is not particularly limited, but for example, a layer on which a pattern or pattern is printed, a film including the printing thereof, or the like can be used. When a display using an optical film laminate is embedded in a material using white or light colors such as automobiles and houses, if the outermost surface layer has the same color or pattern as the peripheral material of the display, seamlessness is achieved. Can be enhanced.

<< Characteristics of optical film laminate >>
The transmitted light (T1) emitted from the light of the C light source incident from the reflection polarizer layer side of the optical film laminate to the diffuser layer side of the optical film laminate was measured according to the JIS Z8722: 2009 standard, and then used as the C light source. The transmission Y value calculated in the above is not particularly limited as long as the effect of the present invention is not impaired, and can be 20 or more and 50 or less, preferably 20 or more and 35 or less (see FIG. 3A). When the Y value of T1 is within the applicable range, the brightness (visibility) is excellent and sufficient whiteness can be obtained, so that the display can be seamlessly connected to the white or light-colored display peripheral members. Can be obtained.

After measuring the reflected light (R1) that the light of the C light source incident from the diffuser element layer side of the optical film laminate is reflected by the optical film laminate and emitted to the diffuser layer side according to the JIS Z8722: 2009 standard, The reflection Y value calculated by the C light source is not particularly limited as long as the effect of the present invention is not impaired, and can be 40 or more and 80 or less, preferably 50 or more and 80 or less, and more preferably 55 or more and 75 or less (). See FIG. 3 (b)). When the Y value of R1 is within such a range, appropriate diffusivity is obtained, so that the screen is excellent in sharpness, and sufficient whiteness is obtained, so that it is seamless with white or light-colored display peripheral members. Can be obtained.

Here, the Y value indicates the visual reflectance (or visual transmittance), and after measuring by the method described in JIS Z8722: 2009 "Color measurement method-reflection and transmission object color", the C light source is used. calculate. The C light source indicates an auxiliary illuminant C specified in JIS Z8720: 2012 “Standard illuminant (standard light) for color measurement and standard light source”.

The optical film laminate of the present invention can have a whiteness WI value of 45 or more and 90 or less in the specular reflection light removal method (SCE) of the D65 light source in the spectrophotometer, preferably 55 or more and 90 or less, and 70. More than 90 or less is more preferable. Here, the D65 light source refers to the standard illuminant D65 specified in JIS Z8720: 2012 “Standard illuminant (standard light) for color measurement and standard light source”. Further, the specular light removal method (SCE) indicates a method of measuring only the diffused light contained in the reflected light. The whiteness WI value indicates a numerical value specified in ASTM E313-73, and is a numerical value indicating the degree of whiteness. When the whiteness WI value of the optical film laminate is within such a range, it has appropriate diffusivity and therefore has excellent visibility, and since sufficient whiteness can be obtained, it can be used as a white or light-colored display peripheral member. It is possible to obtain a display that can realize seamlessness.

The whiteness WI of the optical film laminate of the present invention can be measured by the method described in ASTM E313-73. In the present invention, the whiteness WI measured by SCE excluding the specular reflection component of the D65 light source was used in a spectrocolorimeter (CM-700D manufactured by Konica Minolta).

<< Manufacturing method of optical film laminate >>
The optical film laminate of the present invention can be produced by laminating a reflective polarizer layer and a diffusing element layer directly or via another layer (a). For example, when the pressure-sensitive adhesive layer is used as the other layer (a), the pressure-sensitive adhesive is previously applied on the release film to form the pressure-sensitive adhesive layer, and the pressure-sensitive adhesive layer is applied to the reflective polarizing element layer. Laminate by laminating and heating laminating. An optical film laminate can be obtained by removing the release film of the obtained laminate, overlaying the diffusion element layer on the adhesive layer, and performing heat laminating. The heat laminating can be performed using a known laminator.

<< Applications of optical film laminate >>
The optical film laminate of the present invention is an optical film laminate for a display, and is used by being directly or indirectly laminated with the polarizing plate (A). The display according to the present invention is particularly applicable to displays such as automobile display panels, home appliance display panels, liquid crystal displays embedded in walls, floors, and ceilings of furniture and buildings, organic EL displays, and micro LED displays. Used.

The display according to the present invention may or may not include a polarizing plate (A) (display (D1)) or not (display (D2)).

<Polarizing plate (A)>
The polarizing plate (A) is a plate that allows only light that is polarized or polarized in a specific direction to pass through. A known polarizing plate can be used as the polarizing plate (A), and the polarizing plate (A) is not particularly limited as long as the effect of the present invention is not impaired. Those generally used for displays can be used.

The polarizing plate (A) is arranged on the visual side of the display panel device of the display.

Here, the polarizing plate (A) is
(I) The display panel device included in the display can be stacked and used facing the visible side (that is, when the polarizing plate (A) is included in the display, that is, in the case of the display (D1)).
(II) The polarizing plate (A) is not included in the visible side of the display panel device included in the display (in the case of the display (D2)), and can be used by being laminated on the surface of the display on the visible side.
(III) The polarizing plate (A) is not included in the visible side of the display panel device included in the display (in the case of the display (D2)), and can be laminated on the optical fill laminate of the present invention and used as the polarizing plate laminate. Can,
(IV) A polarizing plate (a polarizing plate (B) different from the polarizing plate (A)) is provided on the visible side of the display panel device of the display, and can be further laminated and used on the surface of the display on the visible side.
(V) A polarizing plate (a polarizing plate (B) different from the polarizing plate (A)) is provided on the visible side of the display panel device of the display, and is laminated on the optical fill laminate of the present invention. Can be used as. Here, in the cases (I) to (III) above, it is possible to obtain a display that has excellent visibility and can be made seamless with respect to the peripheral material of the display in which a white or light color is used. Is suitable. The polarizing plate (B) may be the same as or different from the polarizing plate (A), but the polarizing plates (B) may be arranged so that their transmission axes are in the direction of 0 ± 30 ° or 180 ± 30 °. ..

In the cases of (I) to (V) above, the polarizing plate (A) is used by being laminated directly or via another layer (b) when laminated. Here, the other layer (b) is not particularly limited, but an adhesive layer; an adhesive layer or the like can be used. In addition, the other layer (b) can be colored with a white or other color pigment or dye. By doing so, it is possible to easily adjust the seamlessness between the display and the white or light-colored display peripheral member.

<Arrangement of optical film laminate>
The optical film laminate of the present invention is arranged in the display on the visible side of the polarizing plate (A) directly or via another layer (c) (see FIGS. 1 and 2). At that time, the diffusing element layer of the optical film laminate is arranged so as to be on the visual side of the reflective polarizer layer (see FIGS. 1 and 2). Here, the other layer (c) is not particularly limited, but an adhesive layer; an adhesive layer; a retardation film, a color filter, or the like can be used. In addition, the other layer (c) can be colored with a white or other color pigment or dye. By doing so, it is possible to easily adjust the seamlessness between the display and the white or light-colored display peripheral member.

When arranging the optical film laminate of the present invention, the transmission axis of the reflection polarizer of the optical film laminate and the transmission axis of the polarizing plate (A) are oriented in the direction of 0 ± 30 ° or 180 ± 30 °. Is placed in. Further, the polarized light orthogonal to the transmission axis of the polarizing plate (A) is reflected by the reflective polarizer layer.

By arranging the optical film laminate as described above, the following effects can be obtained. That is, the light emitted from the liquid crystal panel or the organic EL panel is transmitted polarized light by the polarizing plate (A) located on the viewing side. Reflection is achieved by aligning the transmission axis of the reflective polarizer layer of the optical film laminate of the present invention with the transmission axis of the polarizing plate (A) located on the viewing side of the display in the direction of 0 ± 30 ° or 180 ± 30 °. The polarizer layer can (1) suppress a decrease in the transmittance of the light emitted from the polarizing plate (A), and (2) reflect the external light and the diffused light from the diffusing element layer to the reflective polarizer layer. It will be possible. By the interaction between this reflected light and the diffused light generated by the diffused element layer, (3) the white brightness of the display can be enhanced while maintaining good visibility, and it is seamless in white. Can be achieved.

<Polarizing plate laminate in the cases of (III) and (V) above>
As described above, the optical film laminate of the present invention can be used as a polarizing plate laminate by laminating it with the polarizing plate (A) (see FIG. 2).

The polarizing plate laminate is laminated on the reflective polarizer layer of the optical film laminate on the side opposite to the diffuser element layer of the optical film laminate, either directly or via another layer (b) (FIG. 2). reference).

The transmission axis of the polarizing plate (A) of the polarizing plate laminate and the transmission axis of the reflective polarizer layer are arranged so as to have a relationship of 0 ± 30 ° or 180 ± 30 °.

The transmitted light (T2) emitted from the light of the C light source incident from the polarizing plate side of the polarizing plate laminate to the diffusion element layer side of the polarizing plate laminate is measured according to the JIS Z8722: 2009 standard, and then the C light source is used. The transmission Y value calculated in the above is not particularly limited as long as the effect of the present invention is not impaired, and can be 15 or more and 40 or less, preferably 20 or more and 40 or less, and more preferably 25 or more and 40 or less (FIG. 4 (FIG. 4). a) See). When the Y value of T2 is within the applicable range, the brightness (visibility) is excellent and sufficient whiteness can be obtained, so that the display can be seamlessly connected to the white or light-colored display peripheral members. Can be obtained.

After measuring the reflected light (R2) that the light of the C light source incident from the diffuser element layer side of the polarizing plate laminate was reflected by the polarizing plate laminate and emitted to the diffuser layer side according to the JIS Z8722: 2009 standard, The reflection Y value calculated by the C light source is not particularly limited as long as the effect of the present invention is not impaired, and can be 40 or more and 80 or less, preferably 50 or more and 80 or less, and more preferably 65 or more and 80 or less ( See FIG. 4 (b)). When the Y value of R1 is within such a range, appropriate diffusivity is obtained, so that the screen is excellent in sharpness, and sufficient whiteness is obtained, so that it is seamless with white or light-colored display peripheral members. Can be obtained.

The polarizing plate laminate of the present invention can have a whiteness WI value of 45 or more and 90 or less in the specular reflection light removal method (SCE) of the D65 light source in the spectrophotometer, preferably 55 or more and 90 or less, and 70. More than 90 or less is more preferable. Here, the D65 light source refers to the standard illuminant D65 specified in JIS Z8720: 2012 “Standard illuminant (standard light) for color measurement and standard light source”. Further, the specular light removal method (SCE) indicates a method of measuring only the diffused light contained in the reflected light. The whiteness WI value indicates a numerical value specified in ASTM E313-73, and is a numerical value indicating the degree of whiteness. When the whiteness WI value of the optical film laminate is within such a range, it has appropriate diffusivity and therefore has excellent visibility, and since sufficient whiteness can be obtained, it can be used as a white or light-colored display peripheral member. It is possible to obtain a display that can realize seamlessness.

The whiteness WI of the polarizing plate laminate of the present invention can be measured by the method described in ASTM E313-73. In the present invention, the whiteness WI measured by SCE excluding the specular reflection component of the D65 light source was used in a spectrocolorimeter (CM-700D manufactured by Konica Minolta).

The polarizing plate laminate of the present invention can be produced by laminating it directly with an optical film laminate or via another layer (d). Here, the other layer (d) is not particularly limited, but an adhesive layer; an adhesive layer; a retardation film, a color filter, or the like can be used. In addition, the other layer (d) can be colored with a white or other color pigment or dye. By doing so, it is possible to easily adjust the seamlessness between the display and the white or light-colored display peripheral member. For example, when the pressure-sensitive adhesive layer is used as the other layer (d), the pressure-sensitive adhesive is previously applied onto the release film to form the pressure-sensitive adhesive layer, and the pressure-sensitive adhesive layer is formed on the optical film laminate. Laminate by laminating and heat laminating. A polarizing plate laminate can be obtained by removing the release film of the obtained laminate, overlaying the polarizing plate (A) on the pressure-sensitive adhesive layer, and performing heat lamination. The heat laminating can be performed using a known laminator.

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited to these examples.

<Manufacturing of optical film laminate>
(Examples 1 to 7)
An acrylic resin paint in which titanium oxide fine particles are dispersed is applied onto a 100 μm-thick transparent PET film (Cosmo Shine A4301 manufactured by Toyobo Co., Ltd.) and dried to have a specific haze and a specific total light transmittance. Each diffusion element layer 1 to 7 with a PET film was obtained.
The haze and total light transmittance of the diffusing element layer were determined by adjusting the blending amount of the titanium oxide fine particles and the thickness of the diffusing element layer.
Subsequently, for each of the diffusing element layers 1 to 7 with the PET film, the diffusing element layers 1 to 6 are a reflective polarizing element (manufactured by 3M, APF-V3) made of a multilayer polymer stretched film, and the diffusing element layer 7 is a diffusing element layer 7. , Optics of Examples 1 to 7 by laminating a reflective polarizing element (manufactured by Asahi Kasei Co., Ltd., WGF) made of a metal nanowire grid via a 25 μm acrylic transparent adhesive (manufactured by Tomagawa Paper Co., Ltd., TD06A). Film laminates 1 to 7 were obtained.
Table 1 summarizes the materials used for the diffuser layer, the haze, the total light transmittance, the materials used for the reflective polarizer layer, and the total light transmittance of the optical film laminate.

(Example 8)
An acrylic pressure-sensitive adhesive (manufactured by Tomagawa Paper Co., Ltd., TD06D92) having a thickness of 25 μm in which titanium oxide fine particles are dispersed, a haze of 92%, and a total light transmittance of 40% is used as a diffusing element layer 8. Example: A reflective polarizer made of a multilayer polymer stretched film (APF-V3 manufactured by 3M Co., Ltd.) and a transparent PET film (Cosmo Shine A4301 manufactured by Toyobo Co., Ltd.) having a thickness of 100 μm are bonded to each other on the treated surface. An optical film laminate 8 of 8 was obtained.
The haze and total light transmittance of the diffusing element layer were determined by adjusting the blending amount of the titanium oxide fine particles and the thickness of the diffusing element layer.
Table 1 summarizes the materials used for the diffuser layer, the haze, the total light transmittance value, the materials used for the reflective polarizer layer, and the total light transmittance of the optical film laminate.

(Example 9)
A diffusing film (LCF, SO16 manufactured by Tomagawa Paper Co., Ltd.) having a haze of 92% and a total light transmittance of 85%, in which a plurality of columnar regions having different refractive indices are formed inside a transparent resin, is used as a diffusing element. A layer 9 is formed, and a reflective polarizing element (manufactured by 3M, APF-V3) made of a multilayer polymer stretched film is attached to the diffusion element layer via a 25 μm acrylic transparent adhesive (manufactured by Togawa Paper Co., Ltd., TD06A). By combining them, the optical film laminate 9 of Example 9 was obtained.
Table 1 summarizes the materials used for the diffuser layer, the haze, the total light transmittance value, the materials used for the reflective polarizer layer, and the total light transmittance of the optical film laminate.

(Example 10)
A diffusing film (Yupo Corporation, YUPO lighting paper BCR) having a porous resin with a haze of 92% and a total light transmittance of 51% is used as the diffusing element layer 10, and the diffusing element layer has multiple layers. Lamination of the optical film of Example 10 by laminating a reflective polarizer (manufactured by 3M, APF-V3) made of a polymer stretched film via a 25 μm acrylic transparent adhesive (manufactured by Tomagawa Paper Co., Ltd., TD06A). I got a body 10.
Table 1 summarizes the materials used for the diffuser layer, the haze, the total light transmittance value, the materials used for the reflective polarizer layer, and the total light transmittance of the optical film laminate.

(Example 11)
A diffusion film (High Tier YUPO WSF manufactured by YUPO Corporation) having a haze of 95% and a total light transmittance of 31%, which is a composite of a film having porousness inside the resin and a non-woven fabric, is used as the diffusion element layer 11. The diffusing element layer is carried out by laminating a reflective polarizer (manufactured by 3M, APF-V3) made of a multilayer polymer stretched film via a 25 μm acrylic transparent adhesive (manufactured by Tomagawa Paper Co., Ltd., TD06A). The optical film laminate 11 of Example 11 was obtained.
Table 1 summarizes the materials used for the diffuser layer, the haze, the total light transmittance value, the materials used for the reflective polarizer layer, and the total light transmittance of the optical film laminate.

(Example 12)
The acrylic resin coating material in which the titanium oxide fine particles used in Example 4 are dispersed is applied onto the surface of a reflective polarizer (APF-V3 manufactured by 3M) made of a multilayer polymer stretched film, dried, and applied to the surface of the reflective polarizer. The optical film laminate 12 of the present invention provided with the direct diffusing element layer 12 was obtained.
In order to confirm the optical characteristics of the diffuser layer 12, the acrylic resin paint was applied on the treated surface of a transparent PET film (manufactured by Toyobo Co., Ltd., Cosmoshine A4301) having a thickness of 100 μm under the same conditions as in the production of the diffuser 12 of this example. The diffuser layer haze with the PET film obtained by coating and drying was 92%, and the total light transmittance was 50%.
The material used for the diffuser layer, the haze (value with the PET film), the total light transmittance (value with the PET film), and the material used for the reflective polarizer layer, and the total light beam of the optical film laminate. The transmittances are summarized and shown in Table 1.

<Manufacturing of Comparative Example Optical Film Laminate, Diffusing Element Layer, Reflective Polarizer Layer>
(Comparative Example 1)
Acrylic resin paint in which silicone fine particles are dispersed is applied on a transparent PET film (Cosmo Shine A4301 manufactured by Toyobo Co., Ltd.) with a thickness of 100 μm and dried, and the haze is 25% and the total light transmittance is 90%. The diffusion element layer a of Example 1 was obtained.
The haze and total light transmittance of the diffusing element layer were determined by adjusting the blending amount of the silicone fine particles and the thickness of the diffusing element layer. Table 1 summarizes the materials used for the diffusing element layer, haze, and total light transmittance.

(Comparative Examples 2 to 4)
An acrylic resin paint in which titanium oxide fine particles are dispersed is applied onto a 100 μm-thick transparent PET film (Cosmo Shine A4301 manufactured by Toyobo Co., Ltd.) and dried to have a specific haze and a specific total light transmittance. Each diffusion element layer b to d with a PET film was obtained.
The haze and total light transmittance of the diffusing element layer were determined by adjusting the blending amount of the titanium oxide fine particles and the thickness of the diffusing element layer.
Subsequently, an Al vapor-deposited film (total light transmittance of 50%) is attached to the diffusion element layer d with the PET film via a 25 μm acrylic transparent adhesive (manufactured by Tomagawa Paper Manufacturing Co., Ltd., TD06A). , An optical film laminate d of Comparative Example 4 was obtained.
Table 1 summarizes the materials used for the diffuser layer, the haze, the total light transmittance, the materials used for the reflective polarizer layer, and the total light transmittance of the optical film laminate.

(Comparative Example 5)
Only the reflective polarizing element (manufactured by 3M, APF-V3) made of the multilayer polymer stretched film was used as the reflective polarizer V3 of Comparative Example 5.
The materials used for the reflective polarizer layer and their total light transmittance are summarized in Table 1.

Examples 1 to 12 and Comparative Examples 1 to 5 are summarized in Table 1.

<Manufacturing a polarizing plate laminate using an optical film laminate>
(Example 13)
A polarizing plate (polarization degree 99.9%, transmittance 42%) was applied to the optical film laminate 4 produced in Example 4 via a 25 μm acrylic transparent adhesive (manufactured by Tomagawa Paper Manufacturing Co., Ltd., TD06A). The polarizing film laminate 13 of Example 13 was obtained by laminating it on the surface of the optical film laminate on the reflection polarizer side. The bonding with the polarizing plate was configured such that the transmission axis of the polarizing plate was shifted by 15 ° with respect to the transmission axis of the reflective polarizer.

(Example 14)
The same procedure as in Example 13 was carried out except that the transmission axis of the polarizing plate was shifted by 30 ° with respect to the transmission axis of the reflection polarizer of the optical film laminate to obtain the polarizing plate laminate 14 of Example 14. ..

(Comparative Example 6)
The same procedure as in Example 13 was carried out except that the transmission axis of the polarizing plate was shifted by 45 ° with respect to the transmission axis of the reflection polarizer of the optical film laminate to obtain the polarizing plate laminate e of Comparative Example 6. ..

(Comparative Example 7)
A polarizing plate (polarization degree 99.9%, transmittance 42%) was applied to the optical film laminate 4 produced in Example 4 via a 25 μm acrylic transparent adhesive (manufactured by Tomagawa Paper Manufacturing Co., Ltd., TD06A). It was bonded to the surface of the optical film laminate on the diffuser layer side to obtain the polarizing plate laminate f of Comparative Example 7. The bonding with the polarizing plate was such that the transmission axis of the reflective polarizer and the transmission axis of the polarizing plate were in the direction of 0 °.

Examples 13 and 14 and Comparative Examples 6 and 7 are summarized in Table 2.

<Measurement>
(Measurement of total light transmittance and haze)
The total light transmittance and haze of the diffusing element layer and the optical film laminate were both measured using a haze meter (NDH-2000 manufactured by Nippon Denshoku Co., Ltd.), and the total light transmittance was JIS K7361-1. : 1997, Haze measured according to JIS K7136: 2000.
In the haze measurement of the diffusing element layer, a sample having a transparent PET film (Cosmo Shine A4301 manufactured by Toyobo Co., Ltd.) on one surface of the diffusing element layer was used for the measurement.

(Measurement regarding transmission Y value and reflection Y value)
Measurements relating to the transmission Y value and the reflection Y value of the optical film laminates of Examples 1 to 12 and Comparative Example 4, the diffusion element layers of Comparative Examples 1 to 3, and the reflection polarizer layer of Comparative Example 5 are spectroscopically measured. A photometer (UV-2500 manufactured by Shimadzu Corporation) was used for a 2 ° field view.

In the case of the optical film laminate, the transmitted Y value is the transmitted light (T1) that the light of the C light source incident from the reflected polarizer layer side of the optical film laminate emits to the diffuser layer side of the optical film laminate. In the case of a diffuser layer, the light of the C light source incident on the diffuser layer from one surface side is transmitted through the diffuser layer and transmitted from the other surface side, and the transmitted light emitted is reflected by the reflection polarizer. In the case of a layer, the transmitted light emitted by the light of the C light source incident on the reflective polarizer layer from one surface side, transmitted through the reflective polarizer layer and transmitted from the other surface side is emitted from JIS Z8722: 2009. After the measurement according to the standard, the value calculated by the C light source was used as the transmitted Y value.

In the case of the optical film laminate, the reflected Y value is the reflected light (R1) in which the light of the C light source incident from the diffuser layer side of the optical film laminate is reflected by the optical film laminate and emitted to the diffuser layer side. ), In the case of the diffusing element layer, the light of the C light source incident on the diffusing element layer from one surface side is reflected in the diffusing element layer, and the reflected light emitted to the one surface side of the diffusing element layer is emitted. In the case of the reflected polarizer layer, the light of the C light source incident on the reflected polarizer layer from one surface side is reflected in the reflected polarizer layer and emitted to the one surface side of the reflected polarizer layer. After measuring the light according to the JIS Z8722: 2009 standard, the value calculated by the C light source was taken as the reflected Y value.

However, since the optical film laminate and the reflective polarizer layer have a transmission axis, it is necessary to eliminate the influence of their polarization properties. Therefore, in this measurement, for all the examples and comparative examples, when the light source is incident on the evaluation sample, in the case of the sample using the optical film laminate or the reflective polarizer layer, first, the transmission axes possessed by them are present. The azimuth angle is set to 0 ° with reference to the direction, and the average value of the measured value at that time and the measured value when the azimuth is rotated by 90 ° with reference to it is calculated, and the transmission Y value of the evaluation sample is calculated. And the reflection Y value. Further, in the case of the diffusion element layer, since it does not have a transmission axis, an arbitrary evaluation sample arrangement is set to an azimuth angle of 0 °, and the average value of each measured value when the azimuth angle is rotated by 90 ° based on the azimuth angle of 0 °. Was calculated and used as the transmission Y value and the reflection Y value of the evaluation sample.

(Measurement of transmitted Y value and reflected Y value when combined with a polarizing plate)
Each optical film laminate of Examples 1 to 12 and Comparative Example 4, each diffusion element layer of Comparative Examples 1 to 3, and a reflective polarizing element layer of Comparative Example 5 were coated with a 25 μm acrylic transparent adhesive (Tomokawa Paper Mill). The transmission Y value and reflection of the polarizing plate laminate, the polarizing plate diffuser layer, and the polarizing plate reflective polarizer layer bonded to the polarizing plate (polarization degree 99.9%, transmittance 42%) via TD06A manufactured by the same company. The Y value was measured with a spectrophotometer (UV-2500, manufactured by Shimadzu Corporation) in a 2 ° field. In the case of a sample in which a reflective polarizing element layer was used, the bonding with the polarizing plate was arranged so that the transmission axis of the reflection polarizer and the transmission axis of the polarizing plate were the same (0 ° or 180 °). ..

In the case of a sample using an optical film laminate, the transmitted Y value is the transmitted light (T2) in which the light of the C light source incident from the polarizing plate side of the polarizing plate laminate is emitted to the diffuser element layer side of the polarizing plate laminate. ), In the case of a sample using the polarizing element layer, the light of the C light source incident from the polarizing plate side of the polarizing plate diffusion element layer passes through the polarizing plate diffusion element layer to the spreading element layer side of the polarizing plate diffusion element layer. In the case of a sample using a reflective polarizer layer, the light of the C light source incident from the polarizing plate side of the polarizing plate reflective polarizer layer is the reflected light of the polarizing plate reflective polarizer layer. The transmitted light transmitted through the reflecting polarizing element layer to the side was measured according to the JIS Z8722: 2009 standard, and then the value calculated by the C light source was used as the transmitted Y value.

In the case of a sample using an optical film laminate, the reflection Y value is such that the light of the C light source incident from the diffuser layer side of the polarizing plate laminate is reflected by the polarizing plate laminate and emitted to the diffuser layer side. In the case of a sample using the diffuser element layer, the reflected light (R1) is reflected by the light of the C light source incident from the diffuser element layer side of the polarizing plate diffuser layer in the diffused polarizer of the polarizing plate diffuser layer. In the case of a sample using the reflective polarizer layer, the reflected light transmitted through the polarizing plate diffuser layer and emitted to the diffuser layer side is incident from the reflected polarizer layer side of the polarizing plate reflective polarizer layer. The reflected light emitted from the light of the light source is reflected in the reflected polarizer layer of the polarizing plate reflective polarizer layer and transmitted through the polarizing plate reflective polarizer layer to the reflected polarizer layer side, and the reflected light is measured according to the JIS Z8722: 2009 standard. After that, the value calculated by the C light source was used as the reflection Y value.

However, since the optical film laminate and the reflective polarizer layer have a transmission axis, it is necessary to eliminate the influence of their polarization properties. Therefore, in this measurement, in contrast to all the examples and comparative examples in which the polarizing plates are bonded, when the light source is incident on the evaluation sample, in the case of the sample using the optical film laminate or the reflective polarizer layer, first , The azimuth angle is 0 ° with reference to the transmission axis direction of them, and the average value of the measured value at that time and the measured value when the azimuth angle is rotated by 90 ° with reference to it is calculated. The transmission Y value and the reflection Y value of the evaluation sample were used. Further, in the case of the diffusion element layer, since it does not have a transmission axis, an arbitrary evaluation sample arrangement is set to an azimuth angle of 0 °, and the average value of each measured value when the azimuth angle is rotated by 90 ° based on the azimuth angle of 0 °. Was calculated and used as the transmission Y value and the reflection Y value of the evaluation sample.

(Measurement of whiteness)
In contrast to the optical film laminates of Examples 1 to 12 and Comparative Example 4, the diffuser layers of Comparative Examples 1 to 3, and the reflective polarizer layer of Comparative Example 5, the optical film laminate has a reflective polarizer surface. A black PET film with a transmittance of 0% is applied to one side of the diffuser layer on one side of the diffuser layer and on one side of the reflective polarizer layer in the reflective polarizer layer, and a 25 μm acrylic transparent adhesive (manufactured by Tomagawa Paper Co., Ltd.). The optical film laminate and the diffuser layer were bonded together via TD06A), and the whiteness was measured from the diffuser side of the optical film laminate and the diffuser layer, and from the reflection polarizer layer side of the reflective polarizer layer. For the measurement, a spectrocolorimeter (CM-700D, manufactured by Konica Minolta) was used to determine the whiteness: WI (based on ASTM E313-73 standard) in SCE mode and a D65 light source.

However, since the optical film laminate and the reflective polarizer layer have a transmission axis, it is necessary to eliminate the influence of their polarization properties. Therefore, in this measurement, when the light source is incident on the evaluation sample, in the case of the sample using the optical film laminate and the reflective polarizer layer, they are compared with all the examples and the comparative examples in which the black PET film is bonded. Calculates the average value of the measured values when the transmission axis of the is perpendicular to the ground (referred to as the azimuth angle 0 °) and the measured values when the azimuth angle is rotated by 90 ° with reference to it. Then, the transmission Y value and the reflection Y value of the evaluation sample were used. Further, in the case of the diffusion element layer, since it does not have a transmission axis, an arbitrary evaluation sample arrangement is set to an azimuth angle of 0 °, and the average value of each measured value when the azimuth angle is rotated by 90 ° based on the azimuth angle of 0 °. Was calculated and used as the whiteness WI value of the evaluation sample.

Table 3 summarizes the transmission Y value, the reflection Y value, and the whiteness WI value of the structure based on each example.

From the results in Table 3, the polarizing plate laminates in which the polarizing plates were bonded to the optical film laminates of Examples 1 to 12 and the polarizing plate laminates of Examples 13 and 14 had a high transmission Y value of 15 or more. Moreover, the reflection Y value could be as high as 40 or more.

Further, the transmission Y value, which is an index of the brightness of the display, is higher than 20 in Examples 1 to 5, 7 to 10, and 12, and in particular, Examples 1 to 4, 9, and 12 have a higher value than 20. , An even higher value of 25 or more was obtained, indicating that the display was bright and clear.
In addition, the reflection Y value, which is a seamless index, has a higher value of 50 or more in Examples 3 to 14, and in particular, Examples 4 to 6, 10 to 12 have a higher value of 65 or more. It was obtained and showed that a seamless display could be obtained.

As for the whiteness, the higher the reflection Y value, the higher the whiteness WI value, and in this example, a whiteness WI value of 45 or more could be obtained. Further, in Examples 3 to 14, higher numerical values of 55 or more were obtained, and in particular, Examples 4 to 6 and 11 to 14 obtained higher numerical values of 70 or more.

Therefore, by using the optical film laminate of this example in a display, all the values of the transmission Y value, the reflection Y value, and the whiteness WI value can be increased. Among them, in the optical film laminates of Examples 3 to 5, 7 to 10 and 12, all the values of the transmission Y value, the reflection Y value and the whiteness WI value can be made higher, and in particular, the optics of Examples 4 and 12 In the film laminate, all the values of the transmission Y value, the reflection Y value, and the whiteness WI value could be further increased.

When the optical film laminate of the present invention is used for a display, the transmission Y value and the reflection Y value when the optical film laminate is combined with a polarizing plate determine the display characteristics of the display and the superiority or inferiority of seamlessness. it is conceivable that. From the above, in the embodiment of the present invention, since the transmission Y value is sufficiently high, the brightness and sharpness are less likely to be impaired in the visibility when the display is lit, and the reflection Y value is sufficiently high, so that the display is displayed. Since it is possible to realize a seamless white or light color when the light is turned off, it is considered that the display and the seamlessness can be well-balanced.

In order to prove the above, in order to prove the above, the optical film laminates of Examples 1, 4, 9 and 12 are used with respect to a display having a polarizing plate on the viewing side, and the transmission axis of the polarizing plate on the viewing side of the display and the reflection of the optical film laminate. The visibility was confirmed by laminating with a 25 μm acrylic transparent adhesive (manufactured by Tomagawa Paper Manufacturing Co., Ltd., TD06A) in the same direction as the transmission axis of the polarizing element layer.

As a result, in the display having all the optical film laminates, when the display was turned off, the seamlessness was good and the existence of the display could be sufficiently hidden. In addition, the visibility when the display was lit was also bright enough to allow the images and characters to be sufficiently visually recognized on the display having all the optical film laminates, and was clear with little blurring.

On the other hand, in Comparative Example 1, when attached to the polarizing plate, the transmission Y value was as high as 43.1, but the whiteness WI value was 19.6, which was less than half the value of this example. Shown gray.

Further, in Comparative Examples 2 to 4, since the transmission Y value is very low, the display cannot be sufficiently visually recognized.

Further, in Comparative Example 5, the whiteness WI value was the lowest at 2.1, it had a metallic luster, and it reflected like a mirror, and it was not possible to realize seamlessness of white or light color.

Further, Comparative Example 6 is not suitable for the present invention because the transmission axes of the reflective polarizer layer and the polarizing plate are largely deviated from each other by 45 °, so that the transmission Y value is low and the visibility of the display is low. ..

In addition, in Comparative Example 7, the reflective polarizer layer is arranged on the viewer side due to the relationship with the polarizing plate. Therefore, the whiteness WI value is as low as 2.3 and has a metallic luster. However, it was reflected like a mirror, and it was not possible to realize seamless white or light color.

Further, as in Examples 1, 4, 9, and 12, the optical film laminate of Comparative Example 4 is used with respect to a display having a polarizing plate on the viewing side, and the transmission axis of the polarizing plate on the viewing side of the display and optics. The visibility was confirmed by laminating them with a 25 μm acrylic transparent adhesive (manufactured by Tomagawa Paper Manufacturing Co., Ltd., TD06A) in the same direction as the transmission axis of the reflective polarizing element layer of the film laminate.
As a result, when the display was turned off, the seamlessness was good and the existence of the display could be hidden, but the visibility when the display was turned on was that the image was dark and the images and characters were very blurred. It was in a difficult state.

Although the whiteness WI value is focused on in the present invention, it is also possible to intentionally color it to bring it closer to the surrounding hue, or to print a pattern or pattern to bring it closer to the surrounding pattern or pattern. In that case, it does not depend on the whiteness WI value.

10 Optical film laminate 11 Reflective polarizer layer 12 Diffusing element layer 20 Polarizing plate laminate 30 C Light source 100 Internal structure of display (with polarizing plate (A))
110 Display panel device (with polarizing plate (A))
120 Display panel device (without polarizing plate (A))
130 Polarizing plate (A)
200 Internal structure of display (without polarizing plate (A))

Claims

An optical film laminate for a display used by being directly or indirectly laminated with a polarizing plate (A).
The display includes a display panel device.
The polarizing plate (A) is laminated on the visual side of the display panel device directly or via another layer (b).
In the optical film laminate, the reflective polarizer layer and the diffusing element layer are laminated directly or via another layer (a).
The diffuser layer is arranged on the visual side of the reflective polarizer layer.
The optical film laminate is laminated directly on the visible side of the polarizing plate (A) or via another layer (c).
The optical film laminate is arranged so that the transmission axis of the polarizing plate (A) and the transmission axis of the reflection polarizer layer have a relationship of 0 ± 30 ° or 180 ± 30 °.
The reflective polarizer layer is an optical film laminate characterized by reflecting polarized light orthogonal to the transmission axis of the polarizing plate (A).
The reflective polarizer layer includes a first polymer layer and a second polymer layer.
The optical film laminate according to claim 1, wherein either the first polymer layer or the second polymer layer is a naphthalate-based polymer.
The diffusion element layer is any one of a diffusion film in which fine particles are dispersed, a diffusion pressure-sensitive adhesive layer in which fine particles are dispersed, a non-woven fabric, a diffusion film having irregularities on the surface, and a porous film. Item 2. The optical film laminate according to Item 1 or 2.
The optical film according to any one of claims 1 to 3, wherein the haze of the diffusing element layer is 40% or more and 95% or less, and the total light transmittance is 30% or more and 88% or less. Laminated body.
The optical film laminate is
The transmitted light (T1) emitted from the light of the C light source incident from the reflection polarizer layer side of the optical film laminate through the optical film laminate on the diffuser layer side of the optical film laminate is emitted from JIS Z8722: After measuring in a 2 ° field according to the 2009 standard, the transmitted Y value calculated by the C light source is 20 or more and 50 or less.
The light of the C light source incident from the diffuser element layer side of the optical film laminate is reflected by the reflection polarizer of the optical film laminate, and the reflected light (reflected light) emitted through the optical film laminate to the diffuser layer side. Any one of claims 1 to 4, wherein R1) is measured in a 2 ° field according to the JIS Z8722: 2009 standard, and then the reflected Y value calculated by the C light source is 40 or more and 80 or less. The optical film laminate according to the section.
The optical film laminate is characterized in that the whiteness WI value of the D65 light source in the specular colorimeter according to the ASTM E313-73 standard in the specular reflection light removal method (SCE) is 45 or more and 90 or less. The optical film laminate according to any one of claims 1 to 5.
A polarizing plate laminate containing the optical film laminate according to any one of claims 1 to 6 and the polarizing plate (A).
The polarizing plate (A) is laminated on the reflective polarizer layer of the optical film laminate on the side opposite to the diffuser element layer of the optical film laminate, either directly or via another layer (d).
The transmission axis of the polarizing plate (A) and the transmission axis of the reflective polarizer layer of the optical film laminate are arranged so as to be in a direction of 0 ± 30 ° or 180 ± 30 °. Polarizing plate laminate.
The polarizing plate laminate is
The transmitted light (T2) emitted from the light of the C light source incident from the polarizing plate side of the polarizing plate laminate through the polarizing plate laminate on the diffusion element layer side of the polarizing plate laminate is according to JIS Z8722: 2009 standard. The transmitted Y value calculated by the C light source after measuring in the 2 ° field according to the above is 15 or more and 40 or less.
The light of the C light source incident from the diffuser element layer side of the polarizing plate laminate is reflected by the reflective polarizer of the polarizing plate laminate, and the reflected light emitted through the polarizing plate laminate side to the diffuser layer side ( The polarizing plate laminate according to claim 7, wherein R2) is measured in a 2 ° field according to the JIS Z8722: 2009 standard, and then the reflected Y value calculated by the C light source is 40 or more and 80 or less. body.
A display (D1) having a laminated structure including a display panel device, a polarizing plate (A) on the visual side of the display panel device, and an optical film laminate according to any one of claims 1 to 6. hand,
The polarizing plate (A) is laminated directly on the visible side of the display panel device or via another layer (b).
The optical film laminate is laminated directly or via another layer (c) on the viewing side of the polarizing plate (A) so that the diffusion element layer is on the viewing side of the reflective polarizer layer. ,
The optical film laminate is arranged so that the transmission axis of the polarizing plate (A) and the transmission axis of the reflection polarizer layer are oriented in a direction of 0 ± 30 ° or 180 ± 30 °.
The display characterized in that the reflection polarizer layer reflects polarized light orthogonal to the transmission axis of the polarizing plate (A).
A display (D2) having a laminated structure, which includes a display panel device and does not include a polarizing plate on the visual side of the display panel device.
The display (D2) includes the polarizing plate laminate according to claim 7 or 8.
The polarizing plate laminate is laminated directly on the visible side of the display panel device or via another layer (c).
The display is characterized in that the polarizing plate laminate is arranged so that the reflective polarizer layer of the polarizing plate laminate is on the visual side of the polarizing plate (A) of the polarizing plate laminate.