KR20210005063A - Optical laminate and its manufacturing method - Google Patents

Abstract

It is an object of the present invention to provide an optical laminate having a colored layer and suppressing air bubbles. As an optical laminate comprising the front plate 10, the bonding layer 20, and the rear plate 30 in order in the lamination direction, on the first surface of the bonding layer 20 side of the rear plate 30 Alternatively, a colored layer 40 provided on a part of the second surface opposite to the first surface is further provided, and the colored layer 40 has a thickness of 13 μm or less, and the front plate 10 is a front surface of the image display device. The optical laminated body is used by being disposed so as to be located at.

Description

Optical laminate and its manufacturing method

The present invention relates to an optical laminate and a method of manufacturing the same, and also to an image display device and a polarizing plate having a colored layer.

BACKGROUND ART As various image display devices such as a liquid crystal display device and an organic electroluminescent display device, there is known a configuration in which a front plate is provided on the visible side of the display panel for the purpose of protecting the display panel. When the display panel is a touch panel, the front panel may also function as a touch surface.

In Japanese Patent Laid-Open No. 2014-238533 (Patent Document 1), it is described that a front plate is provided on the viewer side of a display panel of an image display device, and in the peripheral portion of the surface of the display panel side of the front plate as a colored layer It is described to provide a printing layer. The colored layer also functions as a shielding layer forming a non-display area of the image display device.

Patent Document 1: Japanese Patent Laid-Open No. 2014-238533

The present inventors have discovered a problem in that bubbles may be generated in the case of having a colored layer, in the case of producing an optical laminate by laminating a layer on which a colored layer is formed and another layer.

The present invention provides an optical laminate with a colored layer and suppresses mixing of air bubbles, an image display device having the optical laminate, a polarizing plate having a colored layer used in the optical laminate, and manufacture of the optical laminate It aims to provide a method.

The present invention provides an optical laminate shown below, an image display device, a polarizing plate having a colored layer, and a method for producing an optical laminate.

[1] 　 As an optical laminate comprising a front plate, a bonding layer, and a back plate in order in a lamination direction, the rear plate on the first surface or the first surface on the side of the bonding layer Further comprises a colored layer provided on a part of the second surface on the opposite side,

The colored layer has a thickness of 13 μm or less,

An optical laminate that is used by arranging the front plate to be positioned on a front surface of an image display device.

[2] 　 further comprising a shielding layer that does not contact the colored layer,

The shielding layer according to [1], wherein the shielding layer is disposed at a position away from the colored layer with respect to the front plate in the stacking direction, and at least partially overlapping the colored layer in a plane direction orthogonal to the stacking direction. Optical laminate.

[3] The optical laminate according to [2], wherein the shielding layer has a thickness of 1 µm or more and 13 µm or less.

[4] The optical layered product according to [2] or [3], wherein the shielding layer contains a black pigment.

[5] 　 The optical laminate is divided into a display area and a non-display area in a plane direction orthogonal to the lamination direction,

The colored layer is provided in the non-display area,

The optical laminate according to any one of [1] to [4], wherein the non-display area has an optical density of 3 or more.

[6] 　 The optical laminate according to any one of [1] to [5], wherein the front plate is a resin film.

[7] 　 The optical laminate according to any one of [1] to [6], wherein the back plate has a polarizing plate.

[8] An image display device comprising the optical laminate according to any one of [1] to [7], wherein the front plate is disposed on the entire surface.

[9] 　 a polarizing plate, and

And a colored layer provided on a part of the surface of the polarizing plate on the viewing side,

The colored layer is a polarizing plate having a colored layer having a thickness of 13 μm or less.

[10] 　 The colored layer according to [9], further comprising a shielding layer on a surface of the polarizing plate opposite to the surface on the viewing side, wherein the shielding layer is provided on the colored layer via the polarizing plate. Polarizer having a.

[11] As a manufacturing method for producing the optical laminate according to [1],

Having a lamination step of laminating the rear plate, the bonding layer, and the front plate to obtain the optical laminate,

The manufacturing method, further comprising a colored layer forming step of forming the colored layer on a part of the first surface or the second surface of the rear plate before the laminating step.

As a manufacturing method for manufacturing the optical laminate according to [12] 　 [2],

A lamination step of laminating the rear plate, the bonding layer, and the front plate to obtain the optical laminate, and

Before the lamination step, having a colored layer forming step of forming the colored layer on a part of the first surface of the back plate,

The manufacturing method, further comprising a shielding layer forming step of forming the shielding layer on the second surface of the rear plate.

According to the present invention, an optical laminate having a colored layer and suppressing generation of bubbles generated during lamination, an image display device having the optical laminate, a polarizing plate having a colored layer used for the optical laminate, and the optical A method for producing a laminate can be provided.

1 is a schematic cross-sectional view of an optical laminate according to an embodiment of the present invention.
2 is a schematic cross-sectional view of a modified example of the optical laminate shown in FIG. 1.
3 is a schematic cross-sectional view of an image display device according to an embodiment of the present invention.
4 is a top view of the optical laminate as viewed from the front plate side.
FIG. 5 is a diagram illustrating an example of a bending form when the image display device is a flexible display.
6 is a schematic cross-sectional view of an image display device according to a first embodiment of the present invention.
7 is a schematic cross-sectional view of an image display device according to a second embodiment of the present invention.
8 is a schematic cross-sectional view of an image display device according to a third embodiment of the present invention.
9 is a schematic cross-sectional view of an image display device according to a fourth embodiment of the present invention.
10 is a schematic cross-sectional view of an image display device according to a fifth embodiment of the present invention.
11 is a schematic cross-sectional view of an image display device according to a sixth embodiment of the present invention.
12 is a cross-sectional view schematically showing an example of a method for manufacturing an optical laminate of the present invention.
13 is a cross-sectional view schematically showing another example of the method for manufacturing an optical laminate of the present invention.

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 each component easier to understand, and the scale of each component shown in the drawings does not necessarily coincide with the scale of the actual component.

[Optical laminate]

1 is a schematic cross-sectional view of an optical laminate according to an embodiment of the present invention. The optical laminated body 100 of this embodiment includes a front plate 10, a bonding layer (first bonding layer) 20, and a rear plate 30 in order from the viewer side. The optical laminated body 100 includes a colored layer 40, and the colored layer 40 is a surface of the rear plate 30 on the first bonding layer 20 side (hereinafter, also referred to as “first surface”). ) Is installed on some of the tops. The colored layer 40 may be provided on a part of the surface of the rear plate 30 on the opposite side to the first surface (hereinafter, also referred to as "second surface"). The optical laminated body 100 may be one in which an optical plate not shown in FIG. 1 is further laminated. As such an optical plate, a front optical plate laminated at a position between the rear plate 30 and the front plate 10, and a rear optical plate laminated at a position opposite to the front plate 10 with respect to the rear plate 30 Can be mentioned. The optical laminate 100 may be divided into a display area A and a non-display area B in a plane direction orthogonal to the stacking direction, and in this case, it is preferable to provide a colored layer 40 in the non-display area B. .

FIG. 2 is a schematic cross-sectional view of an optical laminated body 100' which is a modified example of the optical laminated body 100 shown in FIG. 1. The optical laminated body 100' includes the colored layer 40 on the first surface of the rear plate 30 and the shielding layer 50 on the second surface. In this specification, the shielding layer 50 means that it is provided so as not to contact the colored layer 40 in order to distinguish it from the colored layer 40. The shielding layer 50 is provided at a position away from the colored layer 40 with respect to the front plate 10 in the stacking direction, and at least partially overlapping the colored layer 40 in a plane direction orthogonal to the stacking direction. have. The formation surface of the shielding layer 50 is not limited to the second surface of the rear plate 30, and may be provided on any one surface of the rear optical plate, for example.

In the following, the case where the optical laminate is divided into a display area A and a non-display area B, and the non-display area B includes a colored layer 40 or a colored layer 40 and a shielding layer 50 is taken as an example. Explain.

[Image display device]

3 is a schematic cross-sectional view of an image display device according to an embodiment of the present invention. The image display device 300 of the present embodiment includes an optical laminate 100' including a front plate 10 disposed on the front surface, a display laminate 200 including a display unit, and an optical laminate 100 ) And a second bonding layer 21 interposed between the display laminate 200.

4 is a top view of the image display device 300 as viewed from the front plate 10 side. The non-display area B preferably has an optical density of 3 or more, and more preferably 3.2 or more. When the optical density of the non-display area B is within the above numerical range, elements such as wiring arranged in the non-display area B are sufficiently shielded, and the visibility of the image in the display area A is improved. The colored layer 40 contributes to the improvement of the optical density of the non-display area B. In addition, since the shape and color of the colored layer 40 is visually recognized through the bonding layer 20 and the front plate 10, the colored layer 40 also contributes to the design of the image display device 300. . As long as the colored layer 40 is provided in the non-display area B, the arrangement position in the surface direction is not limited. As with the image display device 300 shown in Figs. 3 and 4, by disposing the colored layer 40 at the periphery, light leakage can be suppressed, and design can be improved in that it is visually recognized like a frame.

The thickness d3 (shown in Fig. 1) of the colored layer 40 is 13 μm or less, preferably 10 μm or less, and more preferably 8 μm or less. When the thickness of the colored layer 40 is within the above numerical range, air bubbles generated at the interface can be suppressed. The thickness of the colored layer 40 is preferably 1 μm or more, and more preferably 2 μm or more. When the thickness of the colored layer 40 is 1 μm or more, the colored layer 40 is easily visually recognized, contributing to improvement in design, and also contributing to improvement in the optical density of the non-display area B.

1 to 3 illustrate the case where the thickness of the colored layer 40 is uniform and the cross-sectional shape is rectangular, but the thickness of the colored layer 40 does not need to be uniform, for example, the thickness toward the inside is increased. It may be a cross-sectional shape having a thinner tapered portion. By having a tapered portion, it is possible to suppress mixing of air that is likely to occur during lamination. When the thickness of the colored layer 40 is not uniform, the numerical range described above as the thickness of the colored layer 40 is the maximum thickness of the colored layer 40.

The shielding layer 50 may be provided at a position at least partially overlapping the colored layer 40 in a plane direction orthogonal to the stacking direction, and is preferably provided in the non-display area B. That is, it is preferable that the shielding layer 50 is provided at a position opposite to the colored layer 40. The shielding layer 50 provided in the non-display area B contributes to the improvement of the optical density of the non-display area B. Therefore, when the optical density of the non-display area B does not reach a desired value only in the colored layer 40, it is preferable to provide the shielding layer 50. In addition, by providing the shielding layer 50, which contributes to the improvement of the optical density of the non-display area B, separately from the colored layer 40, the function of improving the optical density that the colored layer 40 should be responsible for is reduced. Adjustment of the thickness of the layer 40 becomes easy, and air bubbles generated at the interface of the colored layer 40 can be suppressed. The thickness of the shielding layer 50 is preferably 1 µm or more and 13 µm or less, and more preferably 2 µm or more and 10 µm or less.

The total thickness of the colored layer 40 and the shielding layer 50 is preferably 20 µm or less, more preferably 15 µm or less, and still more preferably 12 µm or less. By being within the above numerical range, it is possible to suppress the surface formation of steps on the surface of the optical laminate.

2 and 3 illustrate a case where the thickness of the shielding layer 50 is uniform and the cross-sectional shape is rectangular, but the thickness of the shielding layer 50 may not be uniform, for example, the thickness toward the inside It may be a cross-sectional shape having a thinner tapered portion. By having a tapered portion, it is possible to suppress mixing of air that is likely to occur during lamination. When the thickness of the shielding layer 50 is not uniform, the numerical range described above as the thickness of the shielding layer 50 is the maximum thickness of the shielding layer 50.

The shape and size of the optical laminate 100 in the plane direction corresponds to the shape and size of the image display device 300 in which it is used. The shape of the image display device 300 in the plane direction is preferably a square shape, and more preferably a square shape having a long side and a short side. This square shape is preferably a rectangle. When the shape of the image display device 300 in the plane direction is rectangular, the length of the long side is, for example, 50 mm to 300 mm, preferably 100 mm to 280 mm. The length of the short side is, for example, 30 mm to 250 mm, and preferably 60 mm to 220 mm. When the optical laminated body 100 has a square shape, at least one type of processing consisting of R processing, notch processing, and drilling processing may be performed.

The thickness of the optical laminate 100 is preferably designed appropriately according to the functions of the front plate 10 and the rear plate 30, and is not particularly limited, but is, for example, 40 μm to 300 μm, Preferably it is 70㎛ ~ 200㎛.

The image display device 300 can be configured as a flexible display panel. Fig. 5 shows an example of the bending form when the image display device is a flexible display panel. FIG. 5(a) is a flexible display 305 configured to fold the view-side surface inward, and FIG. 5(b) is a flexible display 306 that can be wound.

When the image display device 300 is a flexible display, cracks or discoloration may be caused by repeatedly applying a bending force to the colored layer 40 or continuously applying a bending force. In the image display device 300, if a crack or discoloration occurs in the colored layer 40, it is not preferable because it is easily visually recognized. In addition, regardless of whether the image display device 300 is a flexible display or not, when the optical laminate 100 alone has flexibility, there is a case where a bending force is applied even when the optical laminate 100 is transported. Therefore, it may cause cracks or discoloration in the colored layer 40.

In the optical laminated body and image display device of the present invention, even if the bending force is repeatedly or continuously applied by setting the stacking position of the colored layer 40 on the first surface or on the second surface of the rear plate 30, The occurrence of cracks and discoloration in the colored layer 40 can be suppressed. The optical laminated body and image display device of the present invention can cause cracks or discoloration of the colored layer 40 to the bending force with the front plate 10 as the inside and the bending force with the front plate 10 as the outside. You can prevent it from occurring.

Compared to the case where the colored layer 40 is disposed on the surface of the front plate 10, the stacking position of the colored layer 40 can be approached to the center in the stacking direction of the optical laminate 100. That is, it can be arrange|positioned behind the optical laminated body 100 rather than the surface of the front plate 10. For this reason, it is considered that the stress generated in the colored layer 40 due to bending is small, and the above effect is exhibited.

Based on this point of view, the distance from the surface of the colored layer 40 near the front plate 10 to the outermost surface of the optical laminates 100 and 100' on the front plate 10 side is d1 When (shown in Figs. 1 and 2), the distance d1 is preferably 50 µm or more, and more preferably 70 µm or more, from the viewpoint of suppression of occurrence of cracks due to warping and absorption of steps. Further, from the surface of the colored layer 40 on the far side from the front plate 10, the outermost surface of the optical laminates 100 and 100' on the side opposite to the side on which the front plate 10 is disposed (the most If the distance to d2 (shown in Figs. 1 and 2) is the distance to the colored layer 40 or the shielding layer 50 when the colored layer 40 or the shielding layer 50 is provided on the surface, the absolute value of "d1-d2" is 0 It may be not less than µm and not more than 50 µm, for example, not more than 30 µm.

The relative size D (%) of the difference between the distance d1 and the distance d2 is preferably 25% or less, more preferably 20% or less, and more preferably 15% or less. The lower limit is not particularly limited, and may be 0%. The relative magnitude D (%) of the difference is the following equation:

D=100×|(d1-d2)/(d1+d2)|

Is calculated from

The image display device 300 can be configured as a touch panel type image display device. A touch panel type image display device includes a touch sensor panel, and the front plate 10 provided in the optical laminate 100' constitutes a touch surface.

Hereinafter, a specific form (first to sixth embodiments) of the image display device according to the present invention will be shown, and each component will be described in detail.

<First embodiment>

6 is a schematic cross-sectional view of an image display device according to a first embodiment of the present invention. The image display device of this embodiment is a touch panel type liquid crystal display device. The liquid crystal display device 301 is a front plate 10, a first bonding layer 20, a polarizing plate 60a, a second bonding layer 21, a touch sensor panel 70, and a liquid crystal display in order from the viewer side. An element unit 81, a polarizing plate 60b, and a backlight unit 90 are provided. The colored layer 40 is provided on a part on the surface (first surface) of the polarizing plate 60a on the first bonding layer 20 side. The shielding layer 50 is provided on a part of the surface (second surface) of the polarizing plate 60a on the side of the second bonding layer 21, and is provided on the colored layer 40 through the polarizing plate 60a. desirable. The liquid crystal display device 301 may be divided into a display area A and a non-display area B in the plane direction, and in this case, it is preferable to include a colored layer 40 and a shielding layer 50 in the non-display area B. Do.

In the liquid crystal display device 301, a laminate comprising a front plate 10, a first bonding layer 20, and a polarizing plate 60a, and having a colored layer 40 and a shielding layer 50 is an optical laminate. It is comprised as 101, and the liquid crystal display device 301 is comprised using this optical laminated body 101. In this embodiment, the polarizing plate 60a also functions as the rear plate 30 of the optical laminate 101.

<2nd embodiment>

7 is a schematic cross-sectional view of an image display device according to a second embodiment of the present invention. The image display device of this embodiment is a touch panel type liquid crystal display device. In the liquid crystal display device 305, with the liquid crystal display device 301 shown in FIG. 6, the colored layer 40 is provided on a part of the surface (second surface) of the polarizing plate 60a on the second bonding layer 21 side. It differs only in that it has been made and that it does not have the shielding layer 50. In the liquid crystal display device 305 of this embodiment, a laminate comprising the front plate 10, the first bonding layer 20, and the polarizing plate 60a, and having the colored layer 40 is an optical laminate 105 ), and a liquid crystal display device 305 is configured using such an optical laminate 105. In this embodiment, the polarizing plate 60a also functions as the rear plate 30 of the optical laminated body 105.

<3rd embodiment>

8 is a schematic cross-sectional view of an image display device according to a third embodiment of the present invention. The image display device of this embodiment is a touch panel type liquid crystal display device. In the liquid crystal display device 306, with the liquid crystal display device 301 shown in FIG. 6, the colored layer 40 is provided on a part of the surface (first surface) on the visible side of the touch sensor panel 70, And not having the shielding layer 50 is different. In the liquid crystal display device 306 of the present embodiment, it is composed of a front plate 10, a first bonding layer 20, a polarizing plate 60a, a second bonding layer 21, and a touch sensor panel 70, The layered product provided with the colored layer 40 is constituted as the optical layered product 106, and the liquid crystal display device 306 is constituted by using the optical layered product 106. In this embodiment, the touch sensor panel 70 also functions as the back plate 30 of the optical laminate 106.

<4th embodiment>

9 is a schematic cross-sectional view of an image display device according to a fourth embodiment of the present invention. The image display device of this embodiment is a touch panel type liquid crystal display device. In the liquid crystal display device 302, the stacking position of the polarizing plate 60a and the touch sensor panel 70 is changed from that of the liquid crystal display device 301 shown in FIG. 6, so that the colored layer 40 is formed of the touch sensor panel 70. It is provided on the surface (first surface) of the first bonding layer 20 side, and the shielding layer 50 is on the surface (second surface) of the second bonding layer 21 side of the touch panel sensor 71 The only difference is that it is installed on.

In the liquid crystal display device 302, a laminate comprising the front plate 10, the first bonding layer 20, and the touch sensor panel 70, and the colored layer 40 and the shielding layer 50 is optically It is constituted as the laminated body 102, and the liquid crystal display device 302 is comprised using this optical laminated body 102. In this embodiment, the touch sensor panel 70 also functions as the back plate 30 of the optical laminate 102.

<Fifth Embodiment>

10 is a schematic cross-sectional view of an image display device according to a fifth embodiment of the present invention. The image display device of this embodiment is a touch panel type organic electroluminescent (EL) display device. The organic EL display device 303 has a front plate 10, a first bonding layer 20, a polarizing plate 60c, a second bonding layer 21, a touch sensor panel 70, in order from the viewing side. An organic EL unit 82 is provided. The organic EL display device 303 includes a colored layer 40 provided on a part of the surface (first surface) of the polarizing plate 60c on the first bonding layer 20 side. The organic EL display device 303 may have a shielding layer 50, and the shielding layer is provided on a part of the surface (second surface) of the polarizing plate 60c on the side of the second bonding layer 21, and It is preferable that it is provided on the colored layer 40 through (60c). The organic EL display device 303 may be divided into a display area A and a non-display area B in the plane direction, and in this case, the colored layer 40 and the shielding layer 50 are provided in the non-display area B.

In the organic EL display device 303, a laminate comprising the front plate 10, the first bonding layer 20, and the polarizing plate 60c, and including the colored layer 40 and the shielding layer 50 is optically laminated. It is composed of a sieve 103, and an organic EL display device 303 is formed by using the optical laminate 103. In this embodiment, the polarizing plate 60c also functions as the rear plate 30 of the optical laminate 103.

<6th embodiment>

11 is a schematic cross-sectional view of an image display device according to a sixth embodiment of the present invention. The image display device of this embodiment is an organic EL display device of a touch panel system. In the organic EL display device 304, the stacking position of the polarizing plate 60c and the touch sensor panel 70 is changed from the organic EL display device 303 shown in FIG. 10, so that the colored layer 40 is It is provided on the surface (first surface) of the first bonding layer 20 side of 70), and the shielding layer 50 is the surface of the second bonding layer 21 side of the touch panel sensor 70 (the second The only difference is that it is installed on the surface).

In the organic EL display device 304, a laminate comprising a front plate 10, a first bonding layer 20, and a touch sensor panel 70, and having a colored layer 40 and a shielding layer 50 It is constituted as the optical laminated body 104, and the organic EL display device 304 is comprised using this optical laminated body 104.

In this embodiment, the touch sensor panel 70 also functions as the back plate 30 of the optical laminate 104.

(Display unit)

Examples of the display units included in the image display device 300 include display units including display elements such as a liquid crystal display element, an organic EL display element, an inorganic EL display element, a plasma display element, and a field emission display element. have.

The image display device 300 can be used as a flexible display. In this case, it is preferable that the display element is a liquid crystal display element, an organic EL display element, or an inorganic EL display element from the viewpoint of providing flexibility.

(Front panel)

The front plate 10 is not limited in material and thickness as long as it is a plate-like body capable of transmitting light, and may be a single layer or a multi-layered body, and a plate-like body made of glass (for example, a glass plate, a glass film, etc.), made of resin. The plate-shaped body (for example, a resin plate, a resin sheet, a resin film, etc.) is illustrated. The front plate 10 may constitute the outermost surface of the image display device.

As the glass plate, tempered glass for displays is preferably used. The thickness of the glass plate is, for example, 50 µm to 1000 µm. By using a glass plate, the front plate 10 having excellent mechanical strength and surface hardness can be configured.

The resin film is not limited as long as it is a resin film that can transmit light.

For example, triacetyl cellulose, acetyl cellulose butyrate, ethylene-vinyl acetate copolymer, propionyl cellulose, butyryl cellulose, acetyl propionyl cellulose, polyester, polystyrene, polyamide, polyetherimide, polyacryl, polyimide, Polyethersulfone, polysulfone, polyethylene, polypropylene, polymethylpentene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetal, polyether ketone, polyether ether ketone, polyether sulfone, polymethyl methacrylic And films formed of polymers such as polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, and polyamideimide. These polymers can be used alone or in combination of two or more. When the image display device 300 is a flexible display, a resin film formed of a polymer such as polyimide, polyamide, and polyamideimide, which can be configured to have excellent flexibility, high strength, and high transparency, is formed. It is used suitably.

The resin film may be a film in which hardness is further improved by providing a hard coat layer on at least one surface of the base film. 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 300 is a touch panel type image display device, since the surface of the front plate 10 becomes a touch surface, a resin film having a hard coat layer is suitably used. By providing a hard coat layer, it can be set as the resin film which improved hardness and scratch property. The hard coat layer is, for example, a cured layer of an ultraviolet curable resin. Examples of the ultraviolet-curable resin include acrylic resins, silicone resins, polyester resins, urethane resins, amide resins, and epoxy resins. The hard coat layer may contain an additive in order to improve strength. The additive is not limited, and inorganic fine particles, organic fine particles, or mixtures thereof are exemplified. The thickness of the resin film is, for example, 30 µm to 2000 µm.

The front plate 10 may not only have a function of protecting the front surface of the image display device 300, but may also have a function as a touch sensor, a blue light cut function, a viewing angle adjustment function, and the like.

(First bonding layer)

The first bonding layer 20 is a layer interposed between the front plate 10 and the rear plate 30, and is an adhesive layer or an adhesive layer. When the first bonding layer 20 is provided at a position in contact with the colored layer 40 (for example, the first, fourth to sixth embodiments), it absorbs the step difference of the colored layer 40 well. It is preferable that it is an adhesive layer from a possible viewpoint.

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

As the (meth)acrylic resin (base polymer) used in the pressure-sensitive adhesive composition, for example, (meth)acrylic acid butyl, (meth)acrylate ethyl, (meth)acrylate isooctyl, (meth)acrylate 2-ethylhexyl, such as ( Polymers or copolymers containing one or two or more kinds of meth)acrylic esters as monomers are suitably used. It is preferable to copolymerize a polar monomer to the base polymer. As a polar monomer, for example, (meth)acrylic acid, (meth)acrylic acid 2-hydroxypropyl, (meth)acrylic acid hydroxyethyl, (meth)acrylamide, N,N-dimethyl aminoethyl (meth)acrylate , Monomers having a carboxyl group, a hydroxyl group, an amide group, an amino group, an epoxy group, and the like, such as glycidyl (meth)acrylate.

The pressure-sensitive adhesive composition may contain only the base polymer, but usually further contains a crosslinking agent. Examples of the crosslinking agent include divalent or higher metal ions, and forming a carboxylic acid metal salt between a carboxyl group; As a polyamine compound, forming an amide bond between a carboxyl group; A polyepoxy compound or a polyol that forms an ester bond between a carboxyl group; As a polyisocyanate compound, what forms an amide bond between a carboxyl group is illustrated. Among them, polyisocyanate compounds are preferable.

The active energy ray-curable pressure-sensitive adhesive composition has a property of curing by irradiation with active energy rays such as ultraviolet rays or electron beams, so it has adhesiveness before active energy ray irradiation and can adhere to an adherend such as a film, and is cured by irradiation with active energy rays. It is a pressure-sensitive adhesive composition having a property that can adjust the adhesive force. It is preferable that an active energy ray-curable pressure-sensitive adhesive composition is 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 crosslinking 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 base polymers, tackifiers, fillers (metal powders or other inorganic powders, etc.), antioxidants, Additives such as an ultraviolet absorber, a dye, a pigment, a colorant, a defoaming agent, a corrosion inhibitor, and a photopolymerization initiator may be included.

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

When the thickness of the first bonding layer 20 is provided at a position in contact with the colored layer 40 (for example, the first, fourth to sixth embodiments), the level of the colored layer 40 is absorbed. From the viewpoint of doing so, it is preferable that it is thicker than the thickness of the colored layer 40, for example, it is preferably 3 μm to 100 μm, and more preferably 5 μm to 50 μm.

(Back panel)

The material and thickness of the back plate 30 are not limited as long as it is a plate-like body capable of transmitting light, and may be a single layer or a multilayer. It is preferable that the thickness of the back plate is 50 µm to 1000 µm. The display unit may not be included in the rear plate.

As the rear plate 30, as described above, components used in a typical image display device, such as polarizing plates 60a and 60c, and touch sensor panel 70, can be used. Using these components as the rear plate 30 is preferable because the number of components of the image display device 300 can be reduced, and thus the thickness of the image display device 300 can be realized.

In the above, the case where the back plate 30 is also the polarizing plates 60a and 60c and the touch sensor panel 70 was illustrated, but the back plate 30 is not limited to these, and the protective film on the visible side of the polarizing plate Or it may be a laminate of a polarizing plate and a touch sensor panel.

As the back plate 30, like the front plate 10, a plate-like body made of glass (for example, a glass plate, a glass film, etc.), a plate-like body made of resin (for example, a resin plate, a resin sheet, and a resin film) Etc.) can also be used. As a specific example of the glass-made plate-shaped body and the resin-made plate-shaped body, the description mentioned above regarding the front plate 10 is applied.

(Colored layer)

The shape and color of the colored layer 40 are not limited, and may be appropriately selected according to the purpose or design of the image display device. The colored layer 40 contains a coloring agent. The colored layer 40 may be formed of a single layer or may be formed of a plurality of layers. When the colored layer 40 is formed of a plurality of layers, in the plurality of layers, at least one layer is a colorant-containing layer containing a colorant, and the remaining layers may contain a colorant or may not contain a colorant. . Examples of the color of the colorant include black, red, white, dark blue, silver, and gold. The colored layer 40 may have, under the colorant-containing layer containing the colorant, a colorant-containing layer having high light-shielding properties, or a base layer for improving adhesion. Further, you may have a transparent protective layer covering the colorant-containing layer.

The colorant may be appropriately selected according to a desired color. Examples of the colorant include inorganic pigments such as titanium dioxide, zinc oxide, carbon black such as acetylene black, iron black, bengala, chrome vermilion, ultramarine blue, cobalt blue, yellow lead, and titanium yellow; Organic pigments or dyes such as phthalocyanine blue, indusrene blue, isoindolinone yellow, benzidine yellow, quinacridone red, polyazo red, perylene red, and aniline black; Metallic pigments made of scale flakes such as aluminum and brass; And pearlescent pigments (pearl pigments) made of scaly flakes such as titanium dioxide-coated mica and basic lead carbonate. In this specification, the metal included in the plating layer is also included in the colorant.

Each layer of the colored layer 40 can be formed according to a method such as a printing method, a coating method, and a plating method. The colored layer 40 may be formed directly on the first surface of the rear plate 30, or may be formed by transferring what is formed on another substrate onto the first surface. Specific examples of the printing method include gravure printing, offset printing, screen printing, and transfer printing from a transfer sheet. Printing according to the printing method may be repeatedly performed to obtain the colored layer 40 having a desired thickness. The ink used in the printing method includes, for example, an ink containing a colorant, a binder, a solvent, and optional additives.

Examples of the binder include chlorinated polyolefin (eg, chlorinated polyethylene, chlorinated polypropylene), polyester resin, urethane resin, acrylic resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer, and cellulose resin. Binder resins may be used alone or in combination of two or more. The binder resin may be a thermally polymerizable resin or a photopolymerizable resin.

In the case of forming the colorant-containing layer according to the printing method, it is preferable to use an ink containing 50 to 200 parts by mass of the colorant relative to 100 parts by mass of the binder resin.

As a specific example of the plating method, known plating methods, such as electrolytic plating, electroless plating, hot dip plating, chemical vapor deposition, and physical vapor deposition, are mentioned. Examples of the physical vapor deposition include an evaporation system including a method of heating and evaporating an evaporation source such as vacuum vapor deposition, molecular beam vapor deposition, and ion beam vapor deposition, and sputtering systems such as magnetron sputtering and ion beam sputtering. These methods can combine patterning as needed. In this specification, the layer formed by the plating method is referred to as a plating layer.

When the colored layer 40 is provided on the periphery of the rear plate 30, it is not limited to a form provided on all sides of the periphery, and may be provided only on a part of the periphery according to a desired design or the like. When the colored layer 40 is provided on the periphery of the rear plate 30, the width can be appropriately determined according to the size of the display area, a desired design, etc., for example, in the range of 1 mm to 20 mm. desirable.

(Polarizer)

Examples of the polarizing plate include a stretched film in which a dye having absorption anisotropy is adsorbed, or a film including a film obtained by coating and curing a dye having absorption anisotropy as a polarizer.

As a dye having absorption anisotropy, a dichroic dye can be mentioned, for example. Specifically, as a dichroic dye, iodine or a dichroic organic dye is used. For dichroic organic dyes, 　C.I. A dichroic direct dye composed of a disazo compound such as DIRECT 　 RED 　 39 　, a dichroic direct dye composed of a compound such as tris azo and tetrakis azo are included. As a film to which a dye having absorption anisotropy is applied as a polarizer, a stretched film in which a dye having absorption anisotropy is adsorbed, or a composition containing a dichroic dye having liquid crystal properties, or a dichroic dye and a polymerizable liquid crystal are included. And a film having a layer obtained by coating and curing the composition described above. The film obtained by coating and curing a dye having absorption anisotropy is preferable because it is not limited to the bending direction as compared to a stretched film to which a dye having absorption anisotropy is adsorbed.

(1) Polarizing plate provided with a stretched film as a polarizer

A polarizing plate provided with a stretched film adsorbing a dye having absorption anisotropy as a polarizer will be described. A stretched film in which a dye having absorption anisotropy, which is a polarizer, is adsorbed is usually a step of uniaxially stretching a polyvinyl alcohol-based resin film, and the dichroic dye is adsorbed by dyeing the polyvinyl alcohol-based resin film with a dichroic dye. It is produced through a step of treating, a step of treating a polyvinyl alcohol-based resin film adsorbed with a dichroic dye with an aqueous boric acid solution, and a step of washing with water after treatment with an aqueous boric acid solution. You may use such a polarizer as it is as a polarizing plate, and you may use the thing which laminated|attached a transparent protective film on one side or both sides of it as a polarizing plate. The thickness of the polarizer thus obtained is preferably 2 µm to 40 µm.

Polyvinyl alcohol-based resin is obtained by saponifying a 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 which can be copolymerized with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamides having an ammonium group.

The degree of saponification of the polyvinyl alcohol-based resin is usually about 85 to 100 mol%, and preferably 98 mol% or more. The polyvinyl alcohol-based resin may be modified, and for example, polyvinyl formal or polyvinyl acetal modified with aldehydes may be used. The degree of polymerization of the polyvinyl alcohol-based resin is usually about 1,000 to 10,000, and preferably in the range of 1,500 to 5,000.

What formed such a polyvinyl alcohol resin into a film is used as the original film of a polarizing plate. The method of forming a film of a polyvinyl alcohol-based resin is not particularly limited, and can be formed by a known method. The film thickness of the polyvinyl alcohol-based original film can be, for example, about 10 μm to 150 μm.

Uniaxial stretching of the polyvinyl alcohol-based resin film can be performed before, simultaneously with, or after dyeing with a dichroic dye. When uniaxial stretching is performed after dyeing, this uniaxial stretching may be performed before boric acid treatment or during boric acid treatment. Moreover, uniaxial stretching can also be performed in these several steps. In uniaxial stretching, between rolls having different circumferential speeds, stretching may be performed uniaxially or uniaxially stretching may be performed using a hot roll. Further, uniaxial stretching may be dry stretching performed in the air, or wet stretching performed in a state in which the polyvinyl alcohol-based resin film is swollen using a solvent. The draw ratio is usually about 3 to 8 times.

The material of the protective film bonded to one side or both sides of the polarizer is not particularly limited, but, for example, a cyclic polyolefin resin film, an cellulose acetate resin film made of a resin such as triacetyl cellulose, and diacetyl cellulose, Polyethylene terephthalate, polyethylene naphthalate, polyester resin film made of a resin such as polybutylene terephthalate, polycarbonate resin film, (meth)acrylic resin film, polypropylene resin film, and other films known in the art Can be mentioned. From the viewpoint of thinning, the thickness of the protective film is usually 300 µm or less, preferably 200 µm or less, more preferably 100 µm or less, and usually 5 µm or more, and preferably 20 µm or more. The protective film may or may not have a retardation.

(2) Polarizing plate provided with a film formed of a liquid crystal layer as a polarizer

A polarizing plate provided with a film formed of a liquid crystal layer as a polarizer will be described. As a film coated with a dye having absorption anisotropy used as a polarizer, a composition containing a dichroic dye having liquid crystal properties, or a film obtained by coating and curing a composition containing a dichroic dye and a liquid crystal compound on a substrate, etc. Can be mentioned. The film may be used as a polarizing plate by peeling the base material or together with the base material, or may be used as a polarizing plate in a configuration having a protective film on one or both sides thereof. As said protective film, the same thing as the polarizing plate provided with the said stretched film as a polarizer is mentioned.

A thin film obtained by coating and curing a dye having absorption anisotropy is preferably thin, but if it is too thin, the strength decreases and workability 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.

As a film obtained by applying the dye having absorption anisotropy, specifically, a film described in Japanese Patent Application Laid-Open No. 2013-37353 or Japanese Patent Application Laid-Open No. 2013-33249 can be mentioned.

The polarizing plate may further include a retardation film. The retardation film may include one or two or more retardation layers. The retardation layer may be a positive A plate such as a λ/4 plate or a λ/2 plate, and a positive C plate. The retardation layer may be formed of a resin film exemplified as a material of the above-described protective film, or may be formed of a layer obtained by curing a polymerizable liquid crystal compound. The retardation film may further contain an alignment film or a base film.

(Touch sensor panel)

As for the touch sensor panel, as long as it is a sensor capable of detecting a touched position, the detection method is not limited, such as a resistive film method, a capacitive coupling method, an optical sensor method, an ultrasonic method, an electromagnetic inductive coupling method, and a surface acoustic wave method. A touch sensor panel is illustrated. In view of low cost, a resistive film type and a capacitive coupling type touch sensor panel are suitably used.

An example of a resistive film type touch sensor panel is a pair of substrates disposed opposite to each other, an insulating spacer sandwiched between the pair of substrates, a transparent conductive film provided as a resistive film on the entire inner surface of each substrate, and touch It is composed of a position detection circuit. In the image display device provided with the resistive film type touch sensor panel, when the surface of the front plate 10 is touched, the opposite resistive film is short-circuited, and a current flows through the resistive film. The touch position detection circuit detects a change in voltage at this time, and the touched position is detected.

An example of a capacitive coupling type touch sensor panel is constituted by a substrate, a position detection transparent electrode provided on the entire surface of the substrate, and a touch position detection circuit. In the image display device provided with the capacitive coupling type touch sensor panel, when the surface of the front plate 10 is touched, the transparent electrode is grounded through the capacitance of the human body at the touched point. The touch position detection circuit detects the ground of the transparent electrode, and the touched position is detected.

The touch sensor panel, for example, can form the above-described resistive film type or capacitive coupling method by interposing a separation layer on the base layer, so that the separation layer is separated between the base layer and the separation layer, and It can be done with an exposed configuration.

(Shielding layer)

The shielding layer 50 is preferably provided so as to correspond to the colored layer 40, and the width of the shielding layer 50 in the plane direction is preferably substantially the same as the width of the colored layer 40 in the plane direction. . The shielding layer contains a colorant. The colorant preferably contains a colorant having a high optical density enhancing function, and preferably contains a black pigment such as carbon black and iron black. The shielding layer 50 may be formed in a single layer or in a plurality of layers. When the optical laminate includes a shielding layer, the colored layer is present between the front plate and the shielding layer.

The shielding layer 50 can be formed according to a method such as a printing method or a coating method. The shielding layer 50 may be formed directly on the second surface of the rear plate 30, or may be formed by transferring what is formed on another substrate onto the second surface. As for the printing method, the above description regarding the colored layer 40 is applied.

(2nd bonding layer)

The second bonding layer 21 is an adhesive layer or an adhesive layer. When the 2nd bonding layer 21 is provided at a position in contact with the colored layer 40 or the shielding layer 50, it is preferable that it is a pressure-sensitive adhesive layer from the viewpoint of being able to absorb such a level difference satisfactorily. As the material of the second bonding layer 21, the above description of the first bonding layer 20 is applied.

[Manufacturing method of optical laminate]

The manufacturing method of the optical laminated body of the present invention has a lamination process of laminating a rear plate, a bonding layer, and a front plate to obtain an optical laminate, and before the lamination process, on the first surface or on the second surface of the rear plate It further has a colored layer forming step of forming a colored layer in a part.

12 is a cross-sectional view schematically showing an example of a method for manufacturing the optical laminate 100' shown in FIG. 2. The manufacturing method shown in FIG. 12 is a step of preparing the back plate 30 (FIG. 12 (a )), and a step of forming a colored layer 40 to form a colored layer 40 on the first surface of the back plate 30 (FIG. 12 ). (b)), a shielding layer forming process of forming the shielding layer 50 on the second surface of the rear plate 30 (Fig. 12(b)), and the rear surface on which the colored layer 40 and the shielding layer 50 are formed It has a lamination process (FIG. 12(e)) of laminating the plate 30, the first bonding layer 20, and the front plate 10 to obtain the optical laminate 100'. The method of forming the colored layer is as described above. Further, the shielding layer forming step of forming the shielding layer 50 on the second surface of the rear plate 30 may be after the lamination step (Fig. 12(e)).

Before the lamination process (Fig. 12(e)), the process of preparing the front plate 10 (Fig. 12(c)), the process of providing the first bonding layer 20 on the surface of the front plate 10 (Fig. You may have 12(d)). According to the above-described manufacturing method, by setting the thickness of the colored layer 40 to 13 μm or less, generation of air bubbles in the first bonding layer 20 can be suppressed.

When the rear plate 30 is a polarizing plate, the colored layer 40 obtained in the intermediate step of the manufacturing method and the rear plate having the shielding layer 50 formed thereon (the laminate obtained in Fig. 12(b)) have a colored layer. It becomes a polarizing plate. The first surface of the rear plate 30 is a surface on the viewing side of the polarizing plate. As described above, the polarizing plate having a colored layer is useful in order to obtain the optical laminate 100 in which the generation of air bubbles is suppressed.

13 is a cross-sectional view schematically showing an example of a method of manufacturing the optical laminate 100 shown in FIG. 1. The manufacturing method shown in FIG. 13 differs from the manufacturing method shown in FIG. 12 only in that it does not have a shielding layer forming step of forming the shielding layer 50. When the back plate 30 is a polarizing plate, the back plate (the laminate obtained in Fig. 13(b)) on which the colored layer 40 obtained in the intermediate step of the manufacturing method is formed becomes a polarizing plate having a colored layer.

[Use of image display device]

The image display device according to the present invention can be used as mobile devices such as smart phones and tablets, televisions, digital photo frames, electronic signs, measuring devices and instruments, office devices, medical devices, computing devices, and the like. According to the present invention, it is possible to suppress the generation of bubbles in the first bonding layer 20, which is easily visually recognized, and thus, it is possible to provide a high-quality image display device in which the occurrence of appearance defects is suppressed.

Example

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

<Preparation of a composition for forming a colorant-containing layer (black)>

[Ink component]

Acetylene black 　15 mass%

Polyester 　75 mass%

Dimethyl glutamate 　2.5% by mass

Succinic acid 　2 mass%

Isophorone 　5.5 mass%

[Hardener]

Aliphatic polyisocyanate 　75% by mass

Ethyl acetate 　25 mass%

[menstruum]

Isophorone

[Preparation method]

With respect to 100 parts by mass of the ink component, 10 parts by mass of a curing agent and 10 parts by mass of a solvent were added and stirred to obtain a composition for forming a colorant-containing layer (black).

<Preparation of the composition for forming a colorant-containing layer (white)>

[Ink component]

Titanium dioxide 　50 mass%

Polyester 　39 mass%

Dimethyl glutamate 　2.5% by mass

Succinic acid 　2 mass%

Isophorone 　6.5 mass%

[Hardener]

Aliphatic polyisocyanate 　75% by mass

Ethyl acetate 　25 mass%

[menstruum]

Isophorone

[Preparation method]

To 100 parts by mass of the ink component, 10 parts by mass of a curing agent and 10 parts by mass of a solvent were added and stirred to obtain a composition for forming a colorant-containing layer (white).

<Preparation of the composition for forming a protective layer (transparent)>

[Ink component]

Polyester 　90 mass%

Dimethyl glutamate 　2.5% by mass

Succinic acid 　2 mass%

Isophorone 　5.5 mass%

[Hardener]

Aliphatic polyisocyanate 　75% by mass

Ethyl acetate 　25 mass%

[menstruum]

Isophorone

[Preparation method]

To 100 parts by mass of the ink component, 10 parts by mass of a curing agent and 10 parts by mass of a solvent were added and stirred to obtain a composition for forming a protective layer.

<Example 1>

(Production of a window film having an adhesive layer)

In the procedure shown in FIG. 12, the optical laminated body of Example 1 was produced. Specifically, as the front plate 10, a 70 μm-thick window film (substrate film 50 μm, each hard coat layer 10 μm, length 177 mm×width 105 mm) in which hard coat layers were formed on both sides of the base film. Prepared (FIG. 12(c)), a (meth)acrylic pressure-sensitive adhesive layer (25 µm thick, 177 mm long x 105 mm wide) was prepared as the first bonding layer 20. The base film of the window film is a polyimide resin film, and the hard coat layer is a layer formed of a composition containing a dendrimer compound having a polyfunctional acrylic group at the terminal. Then, corona treatment was performed on the bonding surface of the window film with the adhesive layer, and the bonding surface of the adhesive layer with the window film. And the window film and the adhesive layer were bonded together, and the window film which has the adhesive layer was obtained (FIG. 12(d)).

(Manufacture of polarizing plate)

After forming the photo-alignment film on the substrate, a composition containing a dichroic dye and a polymerizable liquid crystal compound was applied to the substrate, aligned and cured to obtain a polarizer having a thickness of 2 μm. On the polarizer, a 25 µm-thick triacetylcellulose (TAC) film was bonded to each other through an adhesive layer. A retardation film (17 µm in thickness, layer configuration: overcoat layer (cured layer of acrylic resin composition, 1 µm in thickness)/adhesive layer (thickness) comprising a layer obtained by peeling the base material and curing the liquid crystal compound on the exposed surface 5 μm)/λ/4 plate (thickness 3 μm)/adhesive layer (thickness 5 μm)/positive C plate (thickness 3 μm) consisting of a layer cured with a liquid crystal compound and an alignment film consisting of an alignment film and a layer cured with a liquid crystal compound ) Was formed. The thus-prepared polarizing plate (layer structure of "TAC/polarizer/phase difference film", a thickness of 44 µm, a length of 177 mm x a width of 105 mm) was prepared as the rear plate 30 (Fig. 12(a)).

(Formation of colored layer and shielding layer)

Then, on the surface of the TAC of the polarizing plate (the first surface of the rear plate), the coating thickness after drying was obtained by screen printing using a 460 mesh screen using the composition for forming a colorant-containing layer (black) prepared above as ink. Printing was performed with a discharge amount of 3 µm, and a colored layer 40 composed of a black print layer having a thickness of 3 µm and a width of 5 mm was formed on all sides of the periphery (Fig. 12(b)). Further, on the surface of the retardation film of the polarizing plate (the second surface of the rear plate), a shielding layer 50 made of a black printing layer (thickness 3 μm) was formed in the same manner as the colored layer 40 (Fig. 12 ( b)).

(Production of optical laminate)

Thereafter, corona treatment was performed on the surface of the pressure-sensitive adhesive layer of the window film having the pressure-sensitive adhesive layer and the surface of the TAC side of the polarizing plate, and the window film and the polarizing plate having the pressure-sensitive adhesive layer were laminated so that the corona-treated surface was inside, It bonded using a roll bonding machine, cured with an autoclave, and obtained the optical laminated body of Example 1 (FIG. 12(e)).

All corona treatment was performed under the following conditions.

Frequency: 20kHz/Voltage: 8.6kV/Power: 2.5kW/Speed: 6m/min

<Example 2>

The colored layer 40 and the shielding layer 50 are formed as follows, so that the colored layer 40 is composed of a gold evaporated layer and a transparent protective layer, and the shielding layer 50 is a two-layer black printing layer ( The optical laminate of Example 2 was obtained in the same manner as in Example 1 except for having a configuration consisting of each black print layer having a thickness of 3 µm) (Fig. 12(e)).

On the TAC surface of the polarizing plate (the first surface of the back plate), an e-beam evaporation device (product name: UNIVAC2050, manufactured by UNIVAC) was used to form a 80Å-thick evaporation layer using TiO ₂ as an evaporation source, and then In A deposition layer having a thickness of 500 Å was formed as a deposition source, a deposition layer having a thickness of 150 Å was formed on TiO ₂ as a deposition source, and a deposition layer having a thickness of 150 Å was formed on the Al ₂ O ₃ as a deposition source. . In this way, a gold evaporation layer (thickness <1 μm) composed of four layers was formed. Thereafter, on the colored layer formation region, on the surface of the gold deposition layer, the coating thickness after drying was 5 by screen printing using a 460 mesh screen using the composition for forming a protective layer (transparent) prepared above as ink. A protective layer was formed by printing a discharge amount of µm, and the gold deposited layer in the region where the protective layer was not formed was removed by etching. In this way, a colored layer 40 having a layer configuration (over 5 µm and less than 6 µm in total thickness) is formed of a "gold evaporation layer (thickness <1 µm)/protective layer (thickness 5 µm)" on all sides of the periphery. (Fig. 12(b)).

Next, on the surface of the retardation film of the polarizing plate (the second surface of the rear plate), the same printing as the printing at the time of forming the shielding layer in Example 1 was performed twice, and “black printing layer (thickness 3 μm)/black printing layer” (Thickness 3 µm)” (a total thickness of 6 µm) to form a shielding layer 50 (Fig. 12(b)).

<Example 3>

The colored layer 40 and the shielding layer 50 are formed as follows, so that the colored layer 40 is composed of three white printed layers (thickness of each white printed layer 3 μm), and the shielding layer 50 ) To obtain an optical laminate of Example 3 in the same manner as in Example 1, except for having a configuration consisting of two layers of black printing layers (thickness of each black printing layer is 3 μm) (Fig. 12(e) )).

On the TAC surface of the polarizing plate (the first surface of the back plate), printing similar to the printing at the time of forming the colored layer in Example 1 was performed three times using the composition for forming a colorant-containing layer prepared above (white), and ``white A colored layer 40 having a layer configuration (total thickness of 9 µm) was formed of a print layer (thickness 3 µm)/white print layer (thickness 3 µm)/white print layer (thickness 3 µm)” (Fig. 12(b) )).

Subsequently, on the surface of the retardation film of the polarizing plate (the second surface of the rear plate), printing similar to the printing at the time of forming the shielding layer in Example 1 was performed twice, and “black printing layer (thickness 3 μm)/black printing” Layer (thickness 3 µm)” (total thickness of 6 µm) to form a shielding layer 50 (Fig. 12(b)).

<Example 4>

The optical laminate of Example 4 was obtained in the same manner as in Example 1 except that the colored layer 40 was formed as follows and the shielding layer 50 was not formed (Fig. 13(e)). .

On the TAC surface of the polarizing plate (the first surface of the back plate), the same printing as the printing at the time of forming the colored layer in Example 1 was performed twice, and “black printing layer (thickness 3 μm)/black printing layer (thickness 3). Μm)” (total thickness of 6 µm) was formed (Fig. 13(b)).

<Example 5>

The optical laminate of Example 5 was obtained in the same manner as in Example 1 except that the colored layer 40 was formed as follows and the shielding layer 50 was not formed.

On the surface of the retardation film of the polarizing plate (the second surface of the rear plate), printing similar to the printing at the time of forming the colored layer in Example 1 was performed twice, and “black printing layer (thickness 3 μm)/black printing layer ( The colored layer 40 having a layer structure (total thickness of 6 µm) was formed.

<Example 6>

Except that the colored layer 40 and the shielding layer 50 were not formed on the surface of the polarizing plate, in the same manner as in Example 1, a window film having an adhesive layer and a polarizing plate were laminated to obtain a laminate. On the polarizing plate side of such a laminate, a touch sensor panel having a colored layer prepared in advance via a second bonding layer was bonded so that the colored layer 40 side was inside to obtain an optical laminate of Example 6 (Fig. 8). Of the optical laminate 106). As the second bonding layer, the same (meth)acrylic pressure-sensitive adhesive layer (thickness 25 µm, length 177 mm × width 105 mm　) was used as the first bonding layer.

In this embodiment, a separation layer, a patterned electrode layer, and an insulating layer covering the electrode layer are sequentially stacked on the substrate layer, and the separation layer is exposed on the outermost surface by separating between the substrate layer and the separation layer. The panel was produced. A touch sensor panel thus produced (layer structure of "insulation layer/electrode layer/separation layer", thickness 7 µm, length 177 mm x width 105 mm) was prepared as a rear plate. Next, on the surface of the separating layer of the touch sensor panel (the first surface of the back plate), printing similar to the printing at the time of forming the colored layer in Example 1 was performed twice, and “black printing layer (thickness 3 μm)/ A colored layer 40 having a layer configuration (overall thickness of 6 µm) of "black print layer (thickness 3 µm)" was formed to obtain a touch sensor panel having a colored layer.

<Example 7>

The optical laminate of Example 7 was obtained in the same manner as in Example 1 except that the colored layer 40 was formed as follows, and the shielding layer 50 was not formed (Fig. 13(e)). .

On the TAC surface of the polarizing plate, the same printing as that in the case of forming the colored layer in Example 1 was performed twice to form a "black print layer (thickness 3 µm)/black print layer (thickness 3 µm)." On that, in the same manner as in Example 2, a "gold vapor deposition layer (thickness <1 µm) / protective layer (thickness 5 µm)" was formed, and a "black printing layer (thickness 3 µm)/black printing layer ( A colored layer 40 having a layer structure (over 11 µm and less than 12 µm in total thickness) was formed of a gold vapor deposition layer (thickness <1 µm)/protection layer (thickness 5 µm)" (Fig. 13 ( e)).

<Comparative Example 1>

The optical laminate of Comparative Example 1 was obtained in the same manner as in Example 1 except that the colored layer 40 was formed as follows and the shielding layer 50 was not formed (Fig. 12(e)). .

On the TAC surface of the polarizing plate, the same printing as that in the case of forming the colored layer in Example 1 was performed twice to form a "black print layer (thickness 3 µm)/black print layer (thickness 3 µm)." On that, the same printing as the printing at the time of forming the colored layer in Example 3 was performed to form a "white print layer (thickness 3 µm)/white print layer (thickness 3 µm)/white print layer (thickness 3 µm)". , "Black print layer (thickness 3㎛) / black print layer (thickness 3㎛) / white print layer (thickness 3㎛) / white print layer (thickness 3㎛) / white print layer (thickness 3㎛) A colored layer 40 (total thickness of 15 µm) was formed (Fig. 12(e)).

[Measurement of Optical Density]

Samples in a layered configuration of "substrate/colored layer" in which colored layers were formed on a substrate (polarizing plate prepared in Example 1) in the same order as in each of Examples and Comparative Examples were prepared, and each sample was 5 cm×5 It cut into cm, and it was set as the measurement sample for optical density measurement in each Example and a comparative example. This measurement sample is set in an optical density meter (product name: 361T, manufactured by X-rite), and the upper light source located on the colored layer side of the measurement sample is turned on, focusing on the colored layer of the measurement sample, and the upper light source is turned on. After the light was turned off, the light source for measurement located on the substrate side of the measurement sample was turned on, and the optical density was measured using the colored layer as a measurement area. Table 1 shows the measurement results.

[Evaluation of bubble generation]

For the optical laminates of Examples 1 to 7 and Comparative Example 1, generation of air bubbles was visually confirmed, and evaluation was performed according to the following criteria. Table 3 shows the evaluation results.

A: No air bubbles were observed immediately after bonding,

B: Slight air bubbles were observed immediately after bonding, but no air bubbles were observed after the autobrave treatment.

C: Bubbles were observed only around the colored layer in the bonding layer (non-display area),

D: Bubbles were observed around the colored layer in the bonding layer (non-display area) and in the display area.

[Evaluation of flexibility]

After fixing the optical laminates of Examples 1 to 7 and Comparative Example 1 to a flexure tester (manufactured by Covotech, CFT-720C), the front plate was placed inside so that the distance between films when bent was 5.0 mm (2.5R). The bending test was performed so that it might become. Thereafter, based on the number of flexures (hereinafter referred to as "the number of flexures of occurrence of defects") when cracks or pressure-sensitive adhesive lifting occurred in the bent portion, it was determined as follows.

A: More than 200,000 bending times with defects,

B: Defect occurrence bending frequency 100,000 times or more and less than 200,000 times,

C: Defect occurrence bend frequency 50,000 times or more and less than 100,000 times,

D: Less than 50,000 bending times of defect occurrence.

[Evaluation of step difference]

In the optical laminates of Examples 1 to 7 and Comparative Example 1, the difference between the maximum height and the minimum height of the outermost surface of the front plate was measured, and the difference was determined as follows.

A: less than 50㎛,

B: 50 µm or more and less than 100 µm,

C: 100㎛ or more and less than 500㎛,

D: 500 µm or more.

10 front panel,
20 first bonding layer,
21 second bonding layer,
30 back plate,
40 colored layers,
50 shielding layer,
60a, 60b, 60c polarizer,
70 touch sensor panel,
81 liquid crystal display unit,
82 organic EL display unit,
90 backlight units,
100, 100', 101, 102, 103, 104, 105, 106 optical laminate,
200 indication laminate,
300 image display,
301, 302 liquid crystal display,
303, 304 organic EL display,
305, 306 flexible display.

Claims (12)

As an optical laminate comprising a front plate, a bonding layer, and a back plate in order in a lamination direction,
Further comprising a colored layer provided on a part of the rear plate on the first surface on the bonding layer side or on the second surface on the opposite side to the first surface,
The colored layer has a thickness of 13 μm or less,
An optical laminate that is used by placing the front plate so as to be positioned on a front surface of an image display device. The method of claim 1,
Further comprising a shielding layer that does not contact the colored layer,
The shielding layer is provided at a position away from the colored layer with respect to the front plate in the stacking direction and at a position at least partially overlapping the colored layer in a surface direction orthogonal to the stacking direction. The method of claim 2,
The shielding layer is an optical laminate having a thickness of 1 μm or more and 13 μm or less. The method according to claim 2 or 3,
The said shielding layer is an optical laminated body containing a black pigment. The method according to any one of claims 1 to 4,
The optical laminate is divided into a display area and a non-display area in a plane direction orthogonal to the stacking direction,
The colored layer is provided in the non-display area,
The non-display area has an optical density of 3 or more. The method according to any one of claims 1 to 5,
The front plate is a resin film, the optical laminate. The method according to any one of claims 1 to 6,
The said back plate has a polarizing plate, The optical laminated body. An image display device comprising the optical laminate according to any one of claims 1 to 7, wherein the front plate is disposed on the entire surface. A polarizing plate, and
And a colored layer provided on a part of the surface of the polarizing plate on the viewing side,
The colored layer is a polarizing plate having a colored layer having a thickness of 13 μm or less. The method of claim 9,
A shielding layer is further provided on the surface of the polarizing plate opposite to the surface of the viewing side,
The shielding layer is a polarizing plate having a colored layer provided on the colored layer through the polarizing plate. As a manufacturing method for manufacturing the optical laminate according to claim 1,
It has a lamination step of laminating the rear plate, the bonding layer, and the front plate to obtain the optical laminate,
The manufacturing method, further comprising a colored layer forming step of forming the colored layer on a part of the first surface or on the second surface of the rear plate before the laminating step. As a manufacturing method for manufacturing the optical laminate according to claim 2,
A lamination step of laminating the rear plate, the bonding layer, and the front plate to obtain the optical laminate, and
Before the laminating step, having a colored layer forming step of forming the colored layer on a part of the first surface of the back plate,
The manufacturing method, further comprising a shielding layer forming step of forming the shielding layer on the second surface of the rear plate.

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