JP2021110928A - Flexible optical laminate and image display device - Google Patents

Abstract

To provide a flexible optical laminate which is less susceptible to generation of air bubbles in moist heat environments and makes it difficult to see steps on an outer surface of a product.SOLUTION: A flexible optical laminate 100 provided herein comprises multiple optical members 110, 120 and a coloring layer 130, the multiple optical members 110, 120 being stacked via an adhesive layer 140, and is divided into a display area 101 and a non-display area 102 in a planar view. The coloring layer 130 is formed in the non-display area 102. A level difference between the display area 101 and the non-display area 102 is 1.2 μm or less on an outermost surface of the flexible optical laminate 100 on the viewer side.SELECTED DRAWING: Figure 2

Description

The present invention relates to a flexible optical laminate and further to an image display device.

A touch sensor is often mounted on a display device such as a liquid crystal display device or an organic electroluminescence (EL) display device. A touch sensor is usually composed of a transparent substrate and an electrode portion of a pad formed by connecting the edges of the substrate. It is known that a colored layer is provided on the outer edge portion by screen printing in order to prevent the electrode portion of the pad at the end of the sensor from being visually recognized when the display device is used (Patent Document 1).

Japanese Unexamined Patent Publication No. 2015-076095

The colored layer is generally often formed by screen printing. However, since the colored layer formed by screen printing has a low optical density per unit film thickness and low shielding performance, it may be necessary to form a thick film thickness. The thick colored layer causes a step between the display area and the non-display area, and the step on the outer surface of the product may adversely affect the appearance or bubbles are likely to be generated in a moist heat environment.

An object of the present invention is to provide a flexible optical laminate having an appearance in which a step between a display area and a non-display area is hard to be visually recognized and bubbles are hard to be generated in a moist heat environment.

The present invention provides the following flexible optical laminate and image display device.
[1] A flexible optical laminate including a plurality of optical members and a colored layer.
The plurality of optical members are laminated via an adhesive layer, and the plurality of optical members are laminated.
In plan view, it is divided into a display area and a non-display area.
The colored layer is formed in the non-display area and
A flexible optical laminate having a step difference between the display area and the non-display area of 1.2 μm or less on the outermost surface on the viewing side.
[2] The flexible optical laminate according to [1], wherein the colored layer is formed between at least one optical member among the plurality of optical members and the pressure-sensitive adhesive layer.
[3] The flexible optical laminate according to [1] or [2], wherein the colored layers are formed in two or more layers separated from each other in the stacking direction of the plurality of optical members.
[4] The flexible optical laminate according to any one of [1] to [3], wherein the total thickness of the colored layers is 5 μm or less.
[5] The flexible optical laminate according to any one of [1] to [4], wherein the optical density of the non-display region is 5.0 or more.
[6] The flexible optical laminate according to any one of [1] to [5], wherein the colored layer contains a cured product of an active energy ray-curable resin composition.
[7] The flexible optical laminate according to any one of [1] to [6], wherein the plurality of optical members are at least one selected from the group consisting of a front plate, a polarizing plate, and a lower structure.
[8] An image display device including the flexible optical laminate according to any one of [1] to [7].

According to the present invention, it is possible to provide a flexible optical laminate having an appearance in which a step between a display area and a non-display area is hard to be visually recognized and bubbles are hard to be generated in a moist heat environment.

It is a schematic plan view which shows typically an example of the flexible optical laminated body of this invention. It is schematic cross-sectional view which shows typically an example of the flexible optical laminated body of this invention. It is schematic cross-sectional view which shows typically an example of the flexible optical laminated body of this invention. It is schematic cross-sectional view which shows typically an example of the flexible optical laminated body of this invention. It is schematic cross-sectional view which shows typically the manufacturing method of the flexible optical laminate of this invention. It is schematic cross-sectional view which shows typically an example of the flexible optical laminated body of this invention. An observation image of a step in the appearance evaluation of the flexible optical laminate is shown.

Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments. In all the drawings below, the scale is appropriately adjusted to make it easier to understand each component, and the scale of each component shown in the drawings does not necessarily match the scale of the actual component.

<Flexible optical laminate>
FIG. 1 is a schematic plan view of a flexible optical laminate (hereinafter, may be abbreviated as an optical laminate) according to an embodiment of the present invention. The optical laminate 100 shown in FIG. 1 is divided into a display area 101 and a non-display area 102 in a plan view.

The optical laminate 100 is bendable. Bendable means that it can be bent without causing cracks. The optical laminate 100 may be bendable with the viewing side at least one of the inside and the outside, and preferably the viewing side is inside. When the pressure-sensitive adhesive layer and the colored layer are laminated in contact with each other, the optical laminate 100 may be bendable so that the colored layer is at least one of the inner side and the outer side with respect to the pressure-sensitive adhesive layer. From the viewpoint of bending without causing cracks, it is preferable that the colored layer can be bent so as to be on the outer side of the pressure-sensitive adhesive layer. When the optical laminate 100 includes a plurality of colored layers in contact with the pressure-sensitive adhesive layer in the thickness direction, the colored layer on the outermost side of the bend can be bent so as to be outside the pressure-sensitive adhesive layer when the optical laminate 100 is bent. Is preferable.

As used herein, bending includes a form of bending in which a curved surface is formed at a bent portion. In the form of bending, the radius of curvature of the bent inner surface is not particularly limited. Bending also includes a form of refraction in which the refraction angle of the inner surface is greater than 0 degrees and less than 180 degrees, and a form of folding in which the radius of curvature of the inner surface is close to zero or the refraction angle of the inner surface is 0 degrees. .. The visual viewing side refers to the side opposite to the side to be bonded to the image display element of the optical laminate when the optical laminate is applied to the image display device.

When the flexible optical laminate 100 is used in an image display device described later, the display area 101 is an area where an image is displayed, and the non-display area 102 is an area where an image is not displayed. Therefore, it may be required that electrodes, wiring, and the like are arranged in the non-display area 102, and that light leakage from a display unit provided in the image display device is suppressed. In this case, it is preferable that the non-display region 102 has a sufficient shielding property to the extent that light leakage can be suppressed as well as a concealing property of the electrodes and wiring.

The optical density of the non-display region 102 may be, for example, 5.0 or more, preferably 5.2 or more, and more preferably 5.4 or more from the viewpoint of enhancing the shielding property. Although the upper limit is not particularly limited, the optical density of the non-display region 102 may be 7.0 or less, and may be 6.0 or less. The higher the optical density of the non-display region 102, the easier it is to improve the concealment of the electrodes and wiring, and the easier it is to suppress light leakage from the display unit. The optical density of the non-display region 102 can be adjusted by the type and content of the colorant contained in the colored layer 130, which will be described later, the thickness of the colored layer 130, the number of layers constituting the colored layer 130, and the like. The optical density is measured by the devices and methods described in the Examples below.

The width of the non-display area 102 (the length of the non-display area 102 in the plane direction) is not particularly limited, and may be appropriately selected depending on the size, application, design, and the like of the flexible optical laminate 100. As shown in FIG. 1, when the non-display region 102 is formed on the peripheral edge of the flexible optical laminate 100, the width of the non-display region 102 can be, for example, 0.5 mm or more, and is 3 mm or more. It may be 5 mm or more, and usually 80 mm or less, 60 mm or less, 50 mm or less, 30 mm or less, or 20 mm or less. ..

FIG. 2 is a schematic cross-sectional view of the flexible optical laminate 100. The flexible optical laminate 100 shown in FIG. 2 includes optical members 110 and 120 and a colored layer 130, and the optical members 110 and 120 are laminated via an adhesive layer 140. The colored layer 130 is formed in a non-display region 102 in a plan view of the flexible optical laminate 100. The flexible optical laminate 100 has a step (not shown) of 1.2 μm or less between the display area 101 and the non-display area 102 on the outermost surface on the visual side. The flexible optical laminate 100 can further include a separation layer, a protective layer, and a bonding layer, which will be described later. The flexible optical laminate 100 can have a wear-resistant layer on the outermost surface on the visual side. When the flexible optical laminate 100 has a wear-resistant layer on the outermost surface on the visual side, a hard coat layer can be provided directly under the wear-resistant layer. That is, the optical member 110 can have a wear-resistant layer and a hard coat layer in order from the visual side.

A step between the display area 101 and the non-display area 102 (hereinafter, also simply referred to as a “step”) will be described with reference to FIG. The flexible optical laminate 100 has a step 103 of 1.2 μm or less. In FIG. 3, the step 103 side is the visual recognition side. When the flexible optical laminate 100 is used in an image display device described later, the viewing side is the side opposite to the side attached to the image display element of the flexible optical laminate 100. When the step is 1.2 μm or less, the step tends to be difficult to see, and bubbles tend to be difficult to be generated in a moist heat environment. The step 103 is measured by the measuring method described in the column of Examples described later.

As means for setting the step 103 to 1.2 μm or less, for example, adjusting the thickness of the colored layer described later, forming the colored layer on the surface of the optical member on the adhesive layer side, and the end portion of the colored layer on the display region side. For example, the cross-sectional shape of the above is tapered.

The step 103 is preferably 1.1 μm or less, more preferably 1.0 μm or less, still more preferably 0.9 μm or less, and particularly preferably 0.9 μm or less, from the viewpoint of suppressing air bubbles and improving the appearance in a moist heat environment. Is 0.8 μm or less, particularly preferably 0.7 μm or less, and extremely preferably 0.6 μm or less. The step 103 is usually larger than 0 μm, and may be, for example, 0.001 μm or more, 0.01 μm or more, 0.1 μm or more, or 0.5 μm or more.

The shape of the flexible optical laminate 100 in a plan view may be, for example, a square shape, preferably a square shape having a long side and a short side, and more preferably a rectangle. Each layer constituting the flexible optical laminate 100 may have a corner portion R-processed, an end portion notched, or a hole in the plane in a plan view. In the present specification, the plan view means the view from the thickness direction of the layer.

The thickness of the flexible optical laminate 100 is not particularly limited because it varies depending on the functions and applications required for the flexible optical laminate 100, but is, for example, 20 μm or more and 500 μm or less, preferably 50 μm or more and 300 μm or less, and more preferably 70 μm. It is 200 μm or more and 200 μm or less. The thickness of the flexible optical laminate 100 can be the thickness in the display region.

When the shape of the flexible optical laminate 100 in the plane direction is rectangular, the length of the long side may be, for example, 10 mm or more and 1400 mm or less, preferably 50 mm or more and 600 mm or less, and more preferably 50 mm or more and 200 mm or less. be. The length of the short side is, for example, 5 mm or more and 800 mm or less, preferably 30 mm or more and 500 mm or less, more preferably 30 mm or more and 300 mm or less, and further preferably 40 mm or more and 200 mm or less.

The flexible optical laminate 100 can be used, for example, in a display device or the like. The display device is not particularly limited, and examples thereof include an organic electroluminescence (organic EL) display device, an inorganic electroluminescence (inorganic EL) display device, a liquid crystal display device, and an electroluminescent display device. Since the flexible optical laminate 100 is bendable, it is suitable for a flexible display.

(Colored layer)
The colored layer 130 is formed in the non-display region 102 in the plan view of the flexible optical laminate 100, and is preferably provided on at least a part of the peripheral edge portion of the flexible optical laminate 100 in the plan view of the flexible optical laminate 100. More preferably, it is provided on the entire peripheral edge of the flexible optical laminate 100 so as to form the non-display region 102 shown in FIG. By providing the colored layer 130 so as to border the peripheral edge of the flexible optical laminate 100, the colored layer 130 is visually recognized as a frame, so that the design can be improved.

The colored layer 130 can be formed between at least one optical member of the plurality of optical members and the pressure-sensitive adhesive layer in the thickness direction of the flexible optical laminate 100, and preferably at least one of the plurality of optical members. It is formed on the surface of one optical member on the pressure-sensitive adhesive layer side via at least one of a bonding layer, a separation layer, and a protective layer, which will be described later.

The thickness of the colored layer 130 can be, for example, 3 μm or less. When the thickness of the colored layer 130 is 3 μm or less, the step of the colored layer 130 tends to be easily absorbed by the pressure-sensitive adhesive layer, and the step 103 tends to be small. Further, when the thickness of the colored layer 130 is 3 μm or less, air bubbles are likely to be suppressed in the laminating step, and air bubbles tend to be less likely to be generated in the flexible optical laminate in a moist heat environment. The thickness of the colored layer 130 is preferably 2.5 μm or less, more preferably 2 μm or less, still more preferably 1.5 μm or less from the viewpoint of reducing the step and suppressing the mixing of air bubbles in the bonding step. The thickness of the colored layer 130 alone may be, for example, 0.5 μm or more, preferably 0.7 μm or more, more preferably 1 μm or more, still more preferably 1.2 μm or more from the viewpoint of increasing the optical density. The optical density of the colored layer 130 alone may be, for example, 1.5 or more, preferably 1.8 or more, more preferably 2.5 or more, still more preferably 3 or more, and particularly preferably 3.5 or more. .. When the colored layer 130 has a tapered portion, the thickness of the colored layer 130 can be the maximum thickness of the colored layer 130.

In the flexible optical laminated body 100, two or more colored layers may be formed so as to be separated from each other in the laminating direction of the optical members. For example, the flexible optical laminate 100 may include a colored layer 130 formed on the pressure-sensitive adhesive layer 140 side of the optical member 110 and a colored layer formed on the pressure-sensitive adhesive layer 140 side of the optical member 120. .. When two or more colored layers are formed so as to be separated from each other in the stacking direction of the optical members, the number of colored layers in the stacking direction of the optical members may be, for example, two layers, three layers, four layers, or five layers, which is preferable. Is 2 layers or 3 layers or 4 layers, more preferably 2 layers or 3 layers. The fact that the colored layers are formed so as to be separated from each other in the stacking direction of the optical members means that at least one layer other than the colored layer is formed between the colored layers.

When two or more colored layers are formed so as to be separated from each other in the stacking direction of the optical members, the total thickness of the colored layers may be, for example, 5 μm or less, preferably 4 μm or less, and more preferably 3 μm from the viewpoint of reducing steps. It is as follows. The total thickness of the colored layer may be, for example, 1 μm or more, and is preferably 2 μm or more from the viewpoint of increasing the optical density.

The colored layer 130 can be formed by a method of forming a colored layer containing a colorant in advance and transferring the colored layer 130 onto an optical member (hereinafter, also referred to as a transfer method). Further, the colored layer 130 can be directly formed on the optical member by a printing method using ink or paint, a vapor deposition method using metal pigment powder, a photolithography method, or the like. As a method for forming the colored layer 130, a transfer method and a photolithography method are preferable because the step difference can be easily reduced.

In the transfer method, a separation layer described later is formed on a support such as a glass plate, and a colored layer 130 is formed on the separation layer by a photolithography method using an active energy ray-curable resin composition, and then the support. The colored layer 130 can be transferred to the optical member by laminating the surface on the separation layer side exposed by peeling and the optical member via the laminating layer. In the photolithography method, the active energy ray-curable resin composition can be applied to the separation layer, the coating film of the photosensitive resin composition can be exposed, then developed, and then fired. As the exposure light source, a mercury vapor arc, a carbon arc, an Xe arc, or the like that emits light having a wavelength of 250 nm or more and 450 nm or less can be used.

When the colored layer 130 contains a cured product of the active energy ray-curable resin composition, the colored layer 130 can be composed of a single layer. When the colored layer contains a cured product of the active energy ray-curable resin composition, the colored layer 130 may have an optical density of, for example, 1.8 or more per 1 μm of thickness, preferably 2.0 or more, and more preferably 2. It can be .1 or more, more preferably 2.2 or more.

The active energy ray-curable resin composition preferably contains a colorant from the viewpoint of enhancing the shielding property. Examples of the colorant include carbon black such as acetylene black, iron black, titanium dioxide, zinc flower, petals, chrome vermilion, ultramarine, cobalt blue, yellow lead, titanium yellow and other inorganic pigments; phthalocyanine blue, indance. Organic pigments or dyes such as ren blue, isoindolinone yellow, benzidine yellow, quinacridone red, polyazo red, perylene red, aniline black; metal pigments consisting of scaly foil pieces such as aluminum and brass; titanium dioxide coated mica, basic carbon dioxide Examples thereof include pearl luster pigments (pearl pigments) made of scaly foil pieces such as lead.

The color of the coloring layer 130 is not particularly limited, and may be appropriately selected depending on the intended use, design, and the like. Examples of the color of the coloring layer 130 include black, white, red, dark blue, silver, and gold.

As shown in FIG. 4, the colored layer 130 may have a tapered portion 131 having a tapered end portion so that the thickness on the display region 101 side is reduced. Since the colored layer 130 has the tapered portion 131, the step tends to be small, and the mixing of air bubbles tends to be easily suppressed when the pressure-sensitive adhesive layer 140 is bonded. When the colored layer 130 has the tapered portion 131, the width W of the tapered portion 131, that is, the width W from the end of the colored layer 130 on the display region 101 side to the point P where the maximum thickness of the colored layer 130 is reached is, for example, 2 μm or less. It may be preferably 1.4 μm or more and 2.0 μm or less. The colored layer 130 can have an optical density of 5 or more, preferably 6 or more, and a thickness of, for example, 1.4 μm or more and 2.0 μm or less at a point 2 μm away from the display area 101.

The colored layer 130 preferably has an optical density of 3.0 at a point separated from the end on the display region 101 side by 0.5 μm or more from the viewpoint of suppressing light leakage at the boundary between the non-display region 102 and the display region 101. Secure the above.

The colored layer 130 forms a slope within a width range of 0.5 μm or more and 2 μm or less from the region on the display region 101 side from the viewpoint of suppressing light leakage at the boundary between the non-display region 102 and the display region 101. Can be done. The colored layer 130 can have a uniform thickness in the region on the non-display region 102 side of the slope.

Examples of the means for forming the tapered portion include forming a colored layer by a photolithography method using an active energy ray-curable resin composition.

(Separation layer)
The separation layer has a function for facilitating the separation between the support and the colored layer. The separation layer can be, for example, an inorganic layer or an organic layer. Examples of the material forming the inorganic layer include silicon oxide. As the material for forming the organic material layer, for example, a (meth) acrylic resin composition, an epoxy resin composition, a polyimide resin composition, or the like can be used. The colored layer and the separating layer separated from the support can transfer the separating layer side to the optical member via the bonding layer. The thickness of the separation layer may be, for example, 0.01 μm or more and 1.0 μm or less, preferably 0.05 μm or more and 0.5 μm or less. When the flexible optical laminate has a separation layer, the surface of the separation layer opposite to the colored layer side and the optical member can be bonded via the bonding layer.

(Protective layer)
The flexible optical laminate 100 can further include a protective layer between the separation layer and the coloring layer 130 described above. The protective layer may be a layer containing at least one of an organic insulating film and an inorganic insulating film, and these films are placed on the separation layer before forming the colored layer by a spin coating method, a sputtering method, a vapor deposition method, or the like. Can be formed.

(Optical member)
Each of the optical members 110 and 120 may be a component used in a normal image display device, and may be at least one selected from the group consisting of, for example, a front plate, a polarizing plate, and a substructure. The optical members 110 and 120 may be single-layered or multi-layered, respectively.

(Front plate)
The material and thickness of the front plate are not limited as long as it is a plate-like body capable of transmitting light, and the front plate may have a single-layer structure or a multi-layer structure, and is a glass plate-like body (for example, glass). Examples thereof include a plate (plate, glass film, etc.), a resin plate (for example, a resin plate, a resin sheet, a resin film, etc.), and a laminate of a glass plate and a resin plate. The front plate can be a layer constituting the outermost surface of the image display device on the visual side.

As the glass plate, tempered glass for a display is preferably used. The thickness of the glass plate is, for example, 20 μm or more and 1000 μm or less. By using a glass plate, it is possible to construct an optical member having excellent mechanical strength and surface hardness.

The resin film is not limited as long as it is a resin film capable of transmitting light. For example, triacetyl cellulose, acetyl cellulose butyrate, ethylene-vinyl acetate copolymer, propionyl cellulose, butyryl cellulose, acetyl propionyl cellulose, polyester, polystyrene, polyamide, polyetherimide, poly (meth) acrylic, polyimide, polyether. Polysulfone, polysulfone, polyethylene, polypropylene, polymethylpentene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetal, polyetherketone, polyetheretherketone, polyethersulfone, polymethyl (meth) acrylate, polyethylene terephthalate, polybutylene. Examples thereof include films formed of polymers such as terephthalate, polyethylene naphthalate, polycarbonate and polyamideimide. These polymers can be used alone or in admixture of two or more. When the flexible optical laminate 100 is used for a flexible display, it is made of a polymer such as polyimide, polyamide, or polyamide-imide, which has excellent flexibility and can be configured to have high strength and high transparency. Resin film is preferably used.

When the front plate is a resin film, the resin film may be a film having a hard coat layer provided on at least one surface of the base film to further improve the hardness. The hard coat layer may be formed on one surface of the base film or may be formed on both surfaces. When the image display device described later is a touch panel type image display device, the surface of the front plate serves as a touch surface, so a resin film having a hard coat layer is preferably used. By providing the hard coat layer, a resin film having improved hardness and scratchability can be obtained. The hard coat layer is, for example, a cured layer of an ultraviolet curable resin. Examples of the ultraviolet curable resin include (meth) acrylic resin, silicone resin, polyester resin, urethane resin, amide resin, epoxy resin and the like. The hard coat layer may contain additives to improve strength. Additives are not limited and include inorganic fine particles, organic fine particles, or mixtures thereof. The thickness of the resin film is, for example, 30 μm or more and 2000 μm or less.

It is preferable that an abrasion resistant layer is formed on the visible side of the hard coat layer in order to improve the abrasion resistance and prevent contamination by sebum and the like. When one of the plurality of optical members is a front plate, the front plate can have a wear-resistant layer, and the wear-resistant layer can be a layer constituting the visible side surface of the front plate. The wear resistant layer can include a structure derived from a fluorine compound. As the fluorine compound, a compound having a silicon atom and having a hydrolyzable group such as an alkoxy group or a halogen in the silicon atom is preferable. A coating film can be formed by the dehydration condensation reaction of hydrolyzable groups, and the adhesion of the wear-resistant layer can be improved by reacting with active hydrogen on the surface of the base material. Further, it is preferable that the fluorine compound has a perfluoroalkyl group or a perfluoropolyether structure because it can impart water repellency. Particularly preferred is a fluorine-containing polyorganosiloxane compound having a perfluoropolyether structure and a long-chain alkyl group having 4 or more carbon atoms. It is also preferable to use two or more kinds of compounds as the fluorine compound. Further, the fluorine compound preferably contained is a fluorine-containing organosiloxane compound containing an alkylene group having 2 or more carbon atoms and a perfluoroalkylene group.

The thickness of the wear-resistant layer is, for example, 1 to 20 nm. Further, the abrasion resistant layer has water repellency, and the water contact angle is, for example, about 110 to 125 °. The contact angle hysteresis and the sliding angle measured by the sliding method are about 3 to 20 ° and about 2 to 55 °, respectively. Further, the wear-resistant layer is a silanol condensation catalyst, an antioxidant, a rust preventive, an ultraviolet absorber, a light stabilizer, a fungicide, an antibacterial agent, an antibiotic agent, and an extinguishing agent, as long as the effect of the present invention is not impaired. It may contain various additives such as odorants, pigments, flame retardants, and antistatic agents.

A primer layer may be provided between the abrasion resistant layer and the hard coat layer. Examples of the primer agent include a primer agent such as an ultraviolet curable type, a thermosetting type, a moisture curable type, or a two-component curable type epoxy compound. Further, a polyamic acid may be used as the primer agent, and it is also preferable to use a silane coupling agent. The thickness of the primer layer is, for example, 0.001 to 2 μm.

As a method for obtaining a laminate including an abrasion-resistant layer and a hard coat layer, a primer agent is applied, dried, and cured as necessary on the hard coat layer to form a primer layer, and then a fluorine compound is applied. It can be formed by applying and drying a composition containing the mixture (hereinafter, also referred to as a composition for coating an abrasion resistant layer). Examples of the coating method include a dip coating method, a roll coating method, a bar coating method, a spin coating method, a spray coating method, a die coating method, and a gravure coater method. Further, it is also preferable that the coated surface is subjected to a hydrophilic treatment such as plasma treatment, corona treatment, or ultraviolet treatment before applying the primer agent or the composition for coating the abrasion resistant layer. This laminate can be laminated directly on the front plate, or it can be laminated on another transparent base material and bonded to the front plate using an adhesive or an adhesive.

The front plate not only has a function of protecting the front surface of the image display device, but may also have a function as a touch sensor, a blue light cut function, a viewing angle adjusting function, and the like.

(Polarizer)
The polarizing plate may be a linear polarizing plate or a circular polarizing plate. Examples of the linear polarizing plate include a stretched film or a stretched layer on which a dichroic dye is adsorbed, a film containing a film coated with a dichroic dye and cured, and the like as a polarizer. Specifically, as the dichroic dye, iodine or a dichroic organic dye is used. For dichroic organic dyes, C.I. I. Included are dichroic direct dyes made of disuazo compounds such as DIRECT RED 39 and dichroic direct dyes made of compounds such as trisazo and tetrakisazo.

As a film to which a dichroic dye is applied and cured, which is used as a polarizer, a composition containing a dichroic dye having a liquid crystal property or a composition containing a dichroic dye and a polymerizable liquid crystal is applied and cured. Examples thereof include a film containing a cured product of a polymerizable liquid crystal compound such as a layer obtained by the above process. A film coated with a dichroic dye and cured is preferable because there is no limitation in the bending direction as compared with a stretched film or a stretched layer on which a dichroic dye is adsorbed.

The linear polarizing plate may be composed of only a polarizing element, or may further include a thermoplastic resin film, a base material, an alignment film, and a protective layer in addition to the polarizing element. The thickness of the linear polarizing plate is, for example, 2 μm or more and 100 μm or less, preferably 10 μm or more and 60 μm or less.

(1) A linear polarizing plate having a stretched film or a stretched layer as a polarizer A linear polarizing plate having a stretched film having a dichroic dye adsorbed as a polarizer will be described. A stretched film on which a dichroic dye, which is a polarizer, is adsorbed is usually bicolorized by a step of uniaxially stretching the polyvinyl alcohol-based resin film and dyeing the polyvinyl alcohol-based resin film with the bicolor dye. It can be produced through a step of adsorbing a dye, a step of treating a polyvinyl alcohol-based resin film on which a bicolor dye is adsorbed with an aqueous boric acid solution, and a step of washing with water after the treatment with the aqueous boric acid solution. Such a polarizing element may be used as it is as a linear polarizing plate, or a linear polarizing plate having a thermoplastic resin film described later bonded to one side or both sides thereof may be used. The thickness of the polarizer is preferably 2 μm or more and 40 μm or less, and may be 3 μm or more and 10 μm or less.

The polyvinyl alcohol-based resin is obtained by saponifying the polyvinyl acetate-based resin. As the polyvinyl acetate-based resin, in addition to polyvinyl acetate which is a homopolymer of vinyl acetate, a copolymer of vinyl acetate and another monomer copolymerizable therewith is used. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and (meth) acrylamides having an ammonium group.

The saponification degree of the polyvinyl alcohol-based resin is usually 85 mol% or more and 100 mol% or less, preferably 98 mol% or more. The polyvinyl alcohol-based resin may be modified, and for example, polyvinyl formal or polyvinyl acetal modified with aldehydes can also be used. The degree of polymerization of the polyvinyl alcohol-based resin is usually 1000 or more and 10000 or less, preferably 1500 or more and 5000 or less.

Next, a linear polarizing plate including a stretched layer on which a dichroic dye is adsorbed as a polarizer will be described. The stretched layer on which the dichroic dye, which is a polarizer, is adsorbed is usually a step of applying a coating liquid containing the above-mentioned polyvinyl alcohol-based resin on a base film, a step of uniaxially stretching the obtained laminated film, and uniaxial. A step of dyeing the polyvinyl alcohol-based resin layer of the stretched laminated film with a dichroic dye to adsorb the dichroic dye to form a polarizer, and the film on which the dichroic dye is adsorbed is a boric acid aqueous solution. It can be produced through a step of treating with water and a step of washing with water after treatment with an aqueous boric acid solution.
If necessary, the base film may be peeled off from the polarizer. The material and thickness of the base film may be the same as the material and thickness of the thermoplastic resin film described later.

The polarizing film, which is a stretched film or a stretched layer, may be incorporated into an optical laminate in a form in which a thermoplastic resin film is bonded to one side or both sides thereof. This thermoplastic resin film can function as a protective film for a polarizer or a retardation film. The thermoplastic resin film is, for example, a polyolefin resin such as a chain polyolefin resin (polypropylene resin, etc.), a cyclic polyolefin resin (norbornen resin, etc.); a cellulose resin such as triacetyl cellulose; polyethylene terephthalate, polyethylene na. It can be a film composed of a polyester resin such as phthalate or polybutylene terephthalate; a polycarbonate resin; a (meth) acrylic resin; or a mixture thereof.

From the viewpoint of thinning, the thickness of the thermoplastic resin film is usually 300 μm or less, preferably 200 μm or less, more preferably 100 μm or less, still more preferably 80 μm or less, still more preferably 60 μm or less. Yes, it is usually 5 μm or more, preferably 20 μm or more.
The thermoplastic resin film may or may not have a phase difference.
The thermoplastic resin film can be attached to the polarizer using, for example, an adhesive layer.

(2) A linear polarizing plate having a film coated with a dichroic dye and cured as a polarizer A linear polarizing plate having a film coated with a dichroic dye and cured as a polarizer will be described. The film used as a polarizer, to which a dichroic dye is applied and cured, is obtained by applying a composition containing a dichroic dye having a liquid crystal property or a composition containing a dichroic dye and a liquid crystal compound to a base material. Examples thereof include a film obtained by curing. The film may be used as a linear polarizing plate by peeling off the base material or together with the base material, or may be used as a linear polarizing plate in a configuration having a thermoplastic resin film on one side or both sides thereof.

The base material may be a thermoplastic resin film. The example and thickness of the base material may be the same as those exemplified in the above description of the thermoplastic resin film. The substrate may be a thermoplastic resin film having a hard coat layer, an antireflection layer, or an antistatic layer on at least one surface. The base material may have a hard coat layer, an antireflection layer, an antistatic layer, or the like formed only on the surface on the side where the polarizer is not formed. The base material may have a hard coat layer, an antireflection layer, an antistatic layer, or the like formed only on the surface on the side where the polarizer is formed.

Examples of the thermoplastic resin film include the same one as the linear polarizing plate provided with the stretched film or the stretched layer as a polarizer. The thermoplastic resin film can be attached to the polarizer using, for example, an adhesive or an adhesive.

It is preferable that the film coated with the dichroic dye and cured is thin, but if it is too thin, the strength is lowered and the processability tends to be inferior. The thickness of the film is usually 20 μm or less, preferably 5 μm or less, and more preferably 0.5 μm or more and 3 μm or less.

Specific examples of the film coated with the dichroic dye and cured include those described in JP2013-37353A, JP2013-33249, and the like.

The polarizing plate can be circularly polarized light including a linear polarizing plate and a retardation film. A circularly polarizing plate in which a linearly polarized light layer and a retardation layer are arranged so that the absorption axis of the linearly polarizing plate and the slow axis of the retardation layer are at a predetermined angle can exhibit an antireflection function. When the retardation layer includes the λ / 4 plate, the angle formed by the absorption axis of the linear polarizing plate and the slow axis of the λ / 4 plate can be 45 ° ± 10 °. The linear polarizing plate and the retardation layer may be bonded to each other with an adhesive or an adhesive.

(Substructure)
Examples of the substructure include a touch sensor panel and the like. The touch sensor panel can be arranged on the side opposite to the front plate side of the polarizing plate, or between the polarizing plate and the front plate. As the touch sensor panel, as long as it is a sensor that can detect the touched position, the detection method is not limited, and the resistance film method, the capacitance coupling method, the optical sensor method, the ultrasonic method, and the electromagnetic induction coupling method are used. A touch sensor panel of a method, a surface acoustic wave method, or the like is exemplified. Since the cost is low, a touch sensor panel of a resistance film type or a capacitance coupling type is preferably used.

An example of a resistance film type touch sensor panel is a pair of substrates arranged opposite to each other, an insulating spacer sandwiched between the pair of substrates, and a transparent film provided as a resistance film on the inner front surface of each substrate. It is composed of a conductive film and a touch position detection circuit. In an image display device provided with a resistance film type touch sensor panel, when the surface of the front plate is touched, the opposing resistance films are short-circuited and a current flows through the resistance film. The touch position detection circuit detects the change in voltage at this time, and the touched position is detected.

An example of a capacitance coupling type touch sensor panel is composed of a substrate, a transparent electrode for position detection provided on the entire surface of the substrate, and a touch position detection circuit. In an image display device provided with a capacitance coupling type touch sensor panel, when the surface of the front plate is touched, the transparent electrode is grounded via the capacitance of the human body at the touched point. The touch position detection circuit detects the grounding of the transparent electrode, and the touched position is detected.

(Adhesive layer)
The pressure-sensitive adhesive layer 140 is a layer that is interposed between the optical member 110 and the optical member 120 and adheres them.

The pressure-sensitive adhesive layer can be composed of a pressure-sensitive adhesive composition containing a resin as a main component, such as (meth) acrylic-based, rubber-based, urethane-based, ester-based, silicone-based, and polyvinyl ether-based. Among them, a pressure-sensitive adhesive composition using a (meth) acrylic resin having excellent transparency, weather resistance, heat resistance and the like as a base polymer is preferable. The pressure-sensitive adhesive composition may be an active energy ray-curable type or a thermosetting type.

Examples of the (meth) acrylic resin (base polymer) used in the pressure-sensitive adhesive composition include butyl (meth) acrylate, ethyl (meth) acrylate, isooctyl (meth) acrylate, and 2- (meth) acrylate. A polymer or copolymer containing one or more (meth) acrylic acid esters such as ethylhexyl as a monomer is preferably used. It is preferable that the base polymer is copolymerized with a polar monomer. Examples of the polar monomer include (meth) acrylic acid, 2-hydroxypropyl (meth) acrylate, hydroxyethyl (meth) acrylate, (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylate, and glycidyl (). Examples thereof include monomers having a carboxyl group, a hydroxyl group, an amide group, an amino group, an epoxy group and the like, such as meta) acrylate.

The pressure-sensitive adhesive composition may contain only the above-mentioned base polymer, but usually further contains a cross-linking agent. The cross-linking agent is a divalent or higher metal ion that forms a carboxylic acid metal salt with a carboxyl group; a polyamine compound that forms an amide bond with a carboxyl group; poly. Epoxy compounds and polyols that form an ester bond with a carboxyl group; polyisocyanate compounds that form an amide bond with a carboxyl group are exemplified. Of these, polyisocyanate compounds are preferable.

The active energy ray-curable pressure-sensitive adhesive composition has a property of being cured by being irradiated with active energy rays such as ultraviolet rays and electron beams, and has adhesiveness even before irradiation with active energy rays. It is a pressure-sensitive adhesive composition having the property of being able to adhere to an adherend such as, etc., and being cured by irradiation with active energy rays to adjust the adhesion force. The active energy ray-curable pressure-sensitive adhesive composition is preferably an ultraviolet-curable type. The active energy ray-curable pressure-sensitive adhesive composition further contains an active energy ray-polymerizable compound in addition to the base polymer and the cross-linking agent. Further, if necessary, a photopolymerization initiator, a photosensitizer, or the like may be contained.

The pressure-sensitive adhesive composition includes fine particles for imparting light scattering properties, beads (resin beads, glass beads, etc.), glass fibers, resins other than the base polymer, pressure-sensitive imparting agents, and fillers (metal powders and other inorganic powders). Etc.), antioxidants, UV absorbers, dyes, pigments, colorants, antifoaming agents, corrosion inhibitors, photopolymerization initiators and other additives can be included.

It can be formed by applying an organic solvent diluent of the pressure-sensitive adhesive composition on a substrate and drying it. When the active energy ray-curable pressure-sensitive adhesive composition is used, the formed pressure-sensitive adhesive layer 140 can be irradiated with active energy rays to obtain a cured product having a desired degree of curing.

The thickness of the pressure-sensitive adhesive layer 140 is preferably thicker than the thickness of the colored layer 130, more preferably 4 μm or more, still more preferably 5 μm or more, from the viewpoint of absorbing the step caused by the colored layer 130. The thickness of the pressure-sensitive adhesive layer 140 is preferably 100 μm or less, more preferably 50 μm or less, from the viewpoint of flexibility. The thickness of the pressure-sensitive adhesive layer 140 is the maximum thickness of the pressure-sensitive adhesive layer 140.

(Lated layer)
The bonding layer is a layer composed of a pressure-sensitive adhesive or an adhesive. The bonding layer is arranged to bond the above-mentioned separation layer or protective layer to the optical member. As the pressure-sensitive adhesive used as the material of the bonding layer, the above-mentioned pressure-sensitive adhesive composition can be used, and other pressure-sensitive adhesives, for example, a (meth) acrylic pressure-sensitive adhesive, a styrene-based pressure-sensitive adhesive, which is different from the material of the pressure-sensitive adhesive layer, Silicone-based pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, polyester-based pressure-sensitive adhesives, epoxy-based copolymer pressure-sensitive adhesives, and the like can also be used.

As the adhesive used as the material of the bonding layer, for example, one or a combination of two or more of water-based adhesives, active energy ray-curable adhesives, and the like can be formed. Examples of the water-based adhesive include a polyvinyl alcohol-based resin aqueous solution, a water-based two-component urethane-based emulsion adhesive, and the like. The active energy ray-curable adhesive is an adhesive that cures by irradiating with active energy rays such as ultraviolet rays, and is, for example, an adhesive containing a polymerizable compound and a photopolymerizable initiator, and an adhesive containing a photoreactive resin. , Adhesives containing a binder resin and a photoreactive cross-linking agent, and the like. Examples of the polymerizable compound include photopolymerizable monomers such as a photocurable epoxy monomer, a photocurable acrylic monomer, and a photocurable urethane monomer, and oligomers derived from these monomers. Examples of the photopolymerization initiator include compounds containing substances that generate active species such as neutral radicals, anion radicals, and cationic radicals by irradiating them with active energy rays such as ultraviolet rays.

The thickness of the bonding layer is not particularly limited, but when the pressure-sensitive adhesive layer is used as the bonding layer, it is preferably 10 μm or more, 15 μm or more, 20 μm or more, or 25 μm or more. It may be 200 μm or less, 100 μm or less, or 50 μm or less. When an adhesive layer is used as the bonding layer, the thickness of the bonding layer is preferably 0.1 μm or more, may be 0.5 μm or more, is preferably 10 μm or less, and is 5 μm or less. There may be.

(Manufacturing method of flexible optical laminate)
The manufacturing method of the flexible optical laminate 100 can be, for example, a manufacturing method including a transfer step of forming a colored layer by a transfer method. The method for manufacturing the flexible optical laminate 100 including the transfer step is, for example, a step of preparing the support 134 [FIG. 5 (a)] and a step of forming the separation layer 133 on one surface of the support 134 [FIG. 5]. (B)] and the step of applying the active energy ray-curable resin composition to the surface of the separation layer 133 opposite to the support 134 side to form the coating film 130a of the active energy ray-curable resin composition [ FIG. 5 (c)], a step of forming the colored layer 130 by the photolithography method [FIG. 5 (d)], and a step of laminating the process film 135 on the colored layer 130 [FIG. 5 (e)]. A step of peeling off the support 134 [FIG. 5 (f)] and a step of laminating the separation layer 133 side of the colored layer 130 to the first optical member 110 via the laminating layer 136 to transfer the colored layer 130 [. FIG. 5 (g)], a step of peeling the process film 135 [FIG. 5 (h)], and a step of bonding the pressure-sensitive adhesive layer 140 to the colored layer 130 side of the separation layer 133 [FIG. 5 (i)]. , The step [FIG. 5 (j)] of laminating the second optical member 120 via the pressure-sensitive adhesive layer 140 to obtain the flexible optical laminate 100 can be included.

In the step of forming the separation layer 133 on one surface of the support 134 [FIG. 5 (b)], a protective layer can be further formed on the separation layer 133.

In the step of forming the colored layer 130 by the photolithography method [FIG. 5 (d)], the method of forming the colored layer 130 on the separation layer 133 is as described above, and the photolithography method can be mentioned. Further, after forming the colored layer 130, a flattening layer can be further formed so as to cover the colored layer 130. The flattening layer does not have to be formed.

Examples of the support 134 include a glass plate and the like. The first optical member 110 can be a front plate or a circularly polarizing plate. When the first optical member 110 is a front plate, the second optical member 120 can be a circularly polarizing plate. When the first optical member 110 is a circularly polarizing plate, the second optical member 120 can be a front plate. As the process film 135, for example, a thermoplastic resin film can be used.

At the time of transfer of the colored layer, the colored layer can be attached to the optical member by using an adhesive or an adhesive. The optical member, the pressure-sensitive adhesive layer, and the colored layer can be bonded by using a known device such as a laminator, a roll, or a cell joining machine. The bonded surfaces of the optical member, the pressure-sensitive adhesive layer, and the colored layer can be subjected to surface treatment such as corona treatment or plasma treatment.

(First Embodiment)
The flexible optical laminate according to the first embodiment includes a first optical member, an adhesive layer, a second optical member, an adhesive layer, and a third optical member in this order, and the colored layer is a first. It can be formed on the adhesive layer side of at least one of the 1 optical member, the 2nd optical member, and the 3rd optical member. The flexible optical laminate may have a separation layer. When the flexible optical laminate has a separation layer, the separation layer is arranged on the side opposite to the pressure-sensitive adhesive layer side of the coloring layer. The above description applies to the pressure-sensitive adhesive layer and the colored layer.

The layer structure of the flexible optical laminate 200 according to the first embodiment will be described with reference to FIG. The schematic cross-sectional views shown in FIGS. 6 (a) to 6 (k) correspond to the following layer configurations (1) to (11).
(1) First optical member 201 / colored layer 206 / adhesive layer 202 / second optical member 203 / adhesive layer 204 / third optical member 205
(2) First optical member 201 / colored layer 206 / adhesive layer 202 / colored layer 207 / second optical member 203 / adhesive layer 204 / third optical member 205
(3) First optical member 201 / colored layer 206 / adhesive layer 202 / second optical member 203 / colored layer 207 / adhesive layer 204 / third optical member 205
(4) First optical member 201 / colored layer 206 / adhesive layer 202 / second optical member 203 / adhesive layer 204 / colored layer 207 / third optical member 205
(5) First optical member 201 / adhesive layer 202 / colored layer 206 / second optical member 203 / colored layer 207 / adhesive layer 204 / third optical member 205
(6) First optical member 201 / adhesive layer 202 / colored layer 206 / second optical member 203 / adhesive layer 204 / colored layer 207 / third optical member 205
(7) First optical member 201 / adhesive layer 202 / second optical member 203 / colored layer 206 / adhesive layer 204 / colored layer 207 / third optical member 205
(8) First optical member 201 / colored layer 206 / adhesive layer 202 / colored layer 207 / second optical member 203 / colored layer 208 / adhesive layer 204 / third optical member 205
(9) First optical member 201 / colored layer 206 / adhesive layer 202 / colored layer 207 / second optical member 203 / adhesive layer 204 / colored layer 208 / third optical member 205
(10) First optical member 201 / colored layer 206 / adhesive layer 202 / second optical member 203 / colored layer 207 / adhesive layer 204 / colored layer 208 / third optical member 205
(11) First optical member 201 / adhesive layer 202 / colored layer 206 / second optical member 203 / colored layer 207 / adhesive layer 204 / colored layer 208 / third optical member 205.
In FIG. 6, the first optical member 201 side is the visual viewing side, but the step is not shown. In FIG. 6, the bonded layer is not shown. Further, although the separation layer is not shown in FIG. 6, the flexible optical laminate 200 may have a separation layer. When the flexible optical laminate 200 has a separation layer, the separation layer is arranged on the side opposite to the pressure-sensitive adhesive layer side of the coloring layer (between the coloring layer and the optical member).

The above description of the optical member applies to the examples and preferred ranges of the first optical member 201, the second optical member 203, and the third optical member 205. The combination of the first optical member 201, the second optical member 203, and the third optical member 205 may be, for example, a combination of a front plate, a polarizing plate, and a lower structure, preferably a front plate, a circular polarizing plate, and a touch sensor panel. It is a combination of. When the flexible optical laminate 200 has a front plate, the front plate side can be the viewing side.

<Image display device>
The image display device according to the present invention includes the flexible optical laminate. The image display device is not particularly limited, and examples thereof include an image display device such as an organic EL display device, an inorganic EL display device, a liquid crystal display device, and an electroluminescent display device. The image display device may have a touch panel function. The flexible optical laminate is suitable for a flexible image display device capable of bending or bending. In the image display device, when the flexible optical laminate has a front plate, the flexible optical laminate has the front plate facing the outside (the side opposite to the image display element side, that is, the viewing side) and the viewing side of the image display device. Is placed in.

The image display device according to the present invention can be used as a mobile device such as a smartphone or tablet, a television, a digital photo frame, an electronic signboard, a measuring instrument or an instrument, an office device, a medical device, a computer device, or the like. The image display device according to the present invention has excellent flexibility and is therefore suitable for a flexible display or the like.

Hereinafter, the present invention will be described in more detail with reference to Examples. Unless otherwise specified, "%" and "part" in the example are mass% and parts by mass.

[Measurement of optical density]
The optical laminates obtained in Examples and Comparative Examples were installed in an OD Meter (X-Rite, Model name: 361T) so that the touch sensor panel side was the light emitting part and the front plate side was the light receiving part. The optical density (OD value) of the non-display region of the installed optical laminate was measured.

[Step measurement]
The samples of the optical laminates obtained in Examples and Comparative Examples were fixed on soda lime glass with the front plate side facing the outside (upper surface). The step between the non-display area and the display area of the fixed sample was measured using an interference microscope. The measurement magnification was 10 times, and the measurement mode was VSI mode (vertical scanning interferometer). The scan range was set to a range of 50 μm in the thickness direction of the sample, and the value with the largest height difference was defined as the step between the non-display area and the display area.

[Moisture resistance test]
The optical laminates obtained in Examples and Comparative Examples were allowed to stand for 250 hours in an environment having a temperature of 60 ° C. and a relative humidity of 90%. Then, the surface of the pressure-sensitive adhesive layer of the optical laminate was observed with an optical microscope (manufactured by Olympus Corporation), the number of generated bubbles was counted, and the dimensions of the bubbles were measured.

[Appearance evaluation]
The vicinity of the boundary between the non-display area and the display area was observed by the reflected light of the fluorescent lamp.
When the step was not visible, it was marked as ◯, and when the step was visible, it was marked as x.
FIG. 7 shows an observation image of a step due to the reflected light of the fluorescent lamps of Example 8 and Comparative Example 1. In the observation image of Example 8 shown in FIG. 7 (a), the step is not visually recognized, but in the observation image of Comparative Example 1 shown in FIG. 7 (b), the step (edge of the black colored layer) is visually recognized as shining white.

[Front plate]
A front plate having a thickness of 70 μm (base film 50 μm, each hard coat layer 10 μm, length 179 mm × width 106 mm) having hard coat layers formed on both sides of the base film was prepared.

[Adhesive layer]
An acrylic adhesive sheet A with a double-sided separator (adhesive layer thickness: 5 μm, manufactured by Lintec Corporation) was prepared.

[Touch sensor panel]
Thickness: 33 μm,
Layer structure: Touch sensor pattern (laminate of ITO and cured layer of acrylic resin composition, thickness 7 μm) / adhesive layer (thickness 3 μm) / cyclic olefin resin film (thickness 23 μm)

[Preparation of photosensitive resin composition]
Active energy ray-curable photosensitive resin composition containing carbon black (“CR-BK0951L” manufactured by Samsung SDI Co., Ltd.)

[Preparation of composition for forming colored layer (black)]
(Ink component)
Acetylene Black 10.0% by mass
Polyester 80.0% by mass
Glutaric acid dimethyl ester 2.5% by mass
Succinic acid 2.0% by mass
Isophorone 5.5% by mass
(Hardener)
Aliphatic polyisocyanate 75.0% by mass
Ethyl acetate 25.0% by mass
(solvent)
Isophorone (preparation method)
10 parts by mass of a curing agent and 10 parts by mass of a solvent were added to 100 parts by mass of the ink component, and the mixture was stirred to obtain a colored layer forming composition (black).

[Preparation of Colored Layer Laminated Body 1]
A glass plate was coated with an acrylic resin to form a separation layer. Next, the above-mentioned photosensitive resin composition was applied onto the separation layer so as to have a thickness of 2.4 μm after firing, irradiated with ultraviolet rays, developed, and fired to form a colored layer. A peelable process film was attached onto the colored layer. In this way, a colored layer laminate 1 having a layer structure of a glass plate / separation layer / colored layer / process film was obtained.

[Preparation of colored layer laminate 2]
In the preparation of the colored layer laminate 1 described above, the colored layer laminate 1 is produced in the same manner as in the production of the colored layer laminate 1 except that the photosensitive resin composition is applied so as to have a thickness of 1.2 μm after firing. I got 2.

[Preparation of circularly polarizing plate]
After forming a photoalignment film on a triacetyl cellulose (TAC) film having a thickness of 25 μm, a composition containing a dichroic dye and a polymerizable liquid crystal compound is applied onto the photoalignment film, oriented and cured to achieve a thickness of 2. A 5 μm polarizer was obtained. An acrylic resin composition was applied onto the polarizer and cured to obtain an overcoat layer having a thickness of 1 μm. A retardation film containing a layer obtained by polymerizing and curing a liquid crystal compound on the overcoat layer [thickness 16 μm, layer structure: λ / 4 composed of an adhesive layer (thickness 5 μm) / a layer obtained by curing the liquid crystal compound and an alignment film A plate (thickness 3 μm) / adhesive layer (thickness 5 μm) / positive C plate (thickness 3 μm) composed of a layer in which the liquid crystal compound was cured and an alignment film] was bonded. A circularly polarizing plate (layer structure of "TAC / polarizer / retardation film", thickness 44.5 μm, length 179 mm × width 106 mm) produced in this manner was obtained.

<Example 1>
The glass plate was removed from the colored layer laminate 1 described above, and the surface of the exposed separation layer and one surface of the front plate were bonded via a bonding layer. As the bonding layer, an acrylic pressure-sensitive adhesive layer having a thickness of 25 μm was used. Next, the process film was removed from the colored layer laminate 1, and the exposed surface on the colored layer side and the pressure-sensitive adhesive layer of the acrylic pressure-sensitive adhesive sheet A exposed by removing the separator from one surface were bonded together. The adhesive layer exposed by removing the remaining separator from the bonded acrylic pressure-sensitive adhesive sheet A was bonded to the surface of the circularly polarizing plate on the TAC side. On the retardation film side of the circularly polarizing plate, a further pressure-sensitive adhesive layer of an acrylic pressure-sensitive adhesive sheet A exposed by removing one of the separators was bonded. The touch sensor panel was bonded to the pressure-sensitive adhesive layer exposed by removing the remaining separator from the further acrylic pressure-sensitive adhesive sheet A bonded to the circularly polarizing plate. Each bonded surface was subjected to corona treatment.
In this way, the optics having a layer structure (corresponding to FIG. 6A) of the front plate / bonding layer / separation layer / first colored layer / adhesive layer / circularly polarizing plate / adhesive layer / touch sensor panel. A laminate was produced. The colored layer was formed over the entire peripheral edge of the optical laminate so as to form a non-display area.
The obtained optical laminate was measured for optical density, step measurement, and bubble evaluation. The results are shown in Table 1. In Table 1, the arrangement surface of the colored layer indicates the surface of the optical member arranged via the separation layer when the front plate is on the upper side.

<Example 2>
Optical lamination of Example 2 in the same manner as in Example 1 except that the colored layer laminate 1 was changed to the colored layer laminate 2 and the colored layer was laminated so as to have the composition and thickness of the colored layer shown in Table 1. A body (having a layer structure corresponding to FIG. 6B) was obtained. The obtained optical laminate was measured for optical density, step measurement, and bubble evaluation. The results are shown in Table 1.

<Examples 3 to 11>
The optical laminates of Examples 3 to 11 (corresponding to FIGS. 6 (c) to 6 (k), respectively) in the same manner as in Example 2 except that the colored layers were laminated so as to have the structure of the colored layers shown in Table 1. Has a layered structure). The obtained optical laminate was measured for optical density, step measurement, and bubble evaluation. The results are shown in Table 1.

<Comparative example 1>
On one surface of the front plate, a composition for forming a colored layer (black) was used as an ink, and screen printing was performed using a 460 mesh screen to print a discharge amount such that the coating thickness after drying was 5.5 μm. The mixture was dried for 15 minutes to form a colored layer composed of a printing layer having a thickness of 5.5 μm, and a front plate with a colored layer was obtained.
Next, the colored layer side of the front plate with the colored layer and the base material layer (TAC) side of the circularly polarizing plate were bonded together via the pressure-sensitive adhesive layer. Next, a touch sensor panel was attached to the retardation film side via an adhesive layer.
In this way, an optical laminate having a front plate / first colored layer / adhesive layer / circularly polarizing plate / adhesive layer / touch sensor panel in this order was produced.
The obtained optical laminate was measured for optical density, step measurement, and bubble evaluation. The results are shown in Table 1.

100,200 Flexible optical laminate, 101 display area, 102 non-display area, 103 step, 110, 120 optical member, 130 colored layer, 130a coating film, 131 taper part, 133 separation layer, 134 support, 135 process film, 136 Laminated layer, 140 Adhesive layer, 201, 203, 205 Optical member, 202, 204 Adhesive layer, 206, 207, 208 Colored layer, P Maximum thickness point, W Tapered part width.

When the front plate is a resin film, the resin film may be a film having a hard coat layer provided on at least one surface of the base film to further improve the hardness. The hard coat layer may be formed on one surface of the base film or may be formed on both surfaces. When the image display device described later is a touch panel type image display device, the surface of the front plate serves as a touch surface, so a resin film having a hard coat layer is preferably used. By providing the hard coat layer, a resin film having improved hardness and scratch resistance can be obtained. The hard coat layer is, for example, a cured layer of an ultraviolet curable resin. Examples of the ultraviolet curable resin include (meth) acrylic resin, silicone resin, polyester resin, urethane resin, amide resin, epoxy resin and the like. The hard coat layer may contain additives to improve strength. Additives are not limited and include inorganic fine particles, organic fine particles, or mixtures thereof. The thickness of the resin film is, for example, 30 μm or more and 2000 μm or less.

Polarizing plate may be a circularly polarizing plate and a linearly polarizing plate and the retardation film. A circularly polarizing plate in which a linearly polarized light layer and a retardation layer are arranged so that the absorption axis of the linearly polarizing plate and the slow axis of the retardation layer are at a predetermined angle can exhibit an antireflection function. When the retardation layer includes the λ / 4 plate, the angle formed by the absorption axis of the linear polarizing plate and the slow axis of the λ / 4 plate can be 45 ° ± 10 °. The linear polarizing plate and the retardation layer may be bonded to each other with an adhesive or an adhesive.

Claims (11)

A flexible optical laminate including a plurality of optical members and a colored layer.
The plurality of optical members are laminated via an adhesive layer, and the plurality of optical members are laminated.
In plan view, it is divided into a display area and a non-display area.
The colored layer is formed in the non-display area and
A flexible optical laminate having a step difference between the display area and the non-display area of 1.2 μm or less on the outermost surface on the viewing side. The flexible optical laminate according to claim 1, wherein the colored layer is formed between at least one optical member among the plurality of optical members and the pressure-sensitive adhesive layer. The flexible optical laminate according to claim 1 or 2, wherein the colored layers are formed in two or more layers separated from each other in the stacking direction of the plurality of optical members. The flexible optical laminate according to any one of claims 1 to 3, wherein the total thickness of the colored layers is 5 μm or less. The flexible optical laminate according to any one of claims 1 to 4, wherein the non-display region has an optical density of 5.0 or more. The flexible optical laminate according to any one of claims 1 to 5, wherein the colored layer contains a cured product of an active energy ray-curable resin composition. The flexible optical laminate according to any one of claims 1 to 6, which has an wear-resistant layer on the outermost surface on the visual side. The flexible optical laminate according to claim 7, which has a hard coat layer directly below the abrasion resistant layer. The plurality of optical members include a front plate, and the plurality of optical members include a front plate.
The flexible optical laminate according to claim 7 or 8, wherein the wear-resistant layer constitutes a visible surface of the front plate. The flexible optical laminate according to any one of claims 1 to 9, wherein the plurality of optical members are at least one selected from the group consisting of a front plate, a polarizing plate, and a lower structure. An image display device comprising the flexible optical laminate according to any one of claims 1 to 10.

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