CN116997951A - display device - Google Patents

Abstract

An object of the present invention is to provide a display device (1) capable of suppressing reflected light reflected by a high refractive index layer (45) from entering a light-receiving sensor (42), and further to provide an optical laminate used in the display device (1). body (51). The display device (1) of the present invention has a high refractive index layer (42), a first phase difference layer (31), a linear polarizing layer (11) and a display unit (40) in order from the viewing side. The refractive index of the high refractive index layer (42) is 1.60 or more. The display unit (40) has a display element (41) and a light-receiving sensor (42). The first phase difference layer (31) and the linear polarization layer (11) are laminated so as to cover the display element (41) and the light-receiving sensor (42).

Description

display device

Technical field

The present invention relates to a display device, and also relates to an optical laminate used in the display device.

Background technique

A polarizing plate including a linearly polarizing layer is used as a supply element of polarized light in a display device such as a liquid crystal display device or an organic electroluminescence (EL) display device, as a detection element of polarized light, and as a function of suppressing reflection reflected by the display element. Elements that emit light to the outside are widely used. Display devices equipped with polarizing plates have also been extended to mobile devices such as notebook personal computers, smartphones, and tablet terminals. Patent Document 1 describes that from the viewpoint of expanding the display area and designing the display surface of a mobile device such as a smartphone, a non-display area is provided by recessing the outer edge of the display area when viewed from above.

Normally, no display element or polarizing plate is disposed in the concave non-display area. Therefore, by arranging various sensors such as a camera lens and a light-receiving sensor in the non-display area, it is less likely to adversely affect camera performance and sensor sensitivity.

existing technical documents

patent documents

Patent Document 1: Japanese Patent Application Publication No. 2019-219528

Contents of the invention

The problem to be solved by the invention

In order to further expand the display area of the display surface, it is required to reduce the non-display area. In this case, it is conceivable to arrange various sensors such as a light-receiving sensor in the display area where the display element and the polarizing plate are provided. If the light-receiving sensor is arranged in the display area, the light emitted from the display element is likely to be reflected by the high refractive index layer arranged on the visible side of the polarizing plate and enter the light-receiving sensor. The reflected light incident on the light-receiving sensor may easily cause malfunction of the light-receiving sensor.

An object of the present invention is to provide a display device that can prevent reflected light reflected by the high refractive index layer from entering a light-receiving sensor even if it includes a high refractive index layer on the visible side, and an optical laminate used in the display device.

Means used to solve problems

The present invention provides the following display device.

[1] A display device having a high refractive index layer, a first phase difference layer, a linear polarizing layer and a display unit in order from the viewing side,

The refractive index of the above-mentioned high refractive index layer is 1.60 or more,

The above-mentioned display unit has a display element and a light-receiving sensor,

The first phase difference layer and the linear polarization layer are laminated to cover the display element and the light-receiving sensor.

[2] The display device according to [1], wherein the first retardation layer covers the entire visible side of the linearly polarizing layer in plan view.

[3] The display device according to [1] or [2], wherein the linearly polarizing layer has a visibility correction single transmittance of 42% or more.

[4] The display device according to any one of [1] to [3], wherein the angle formed by the slow axis of the first retardation layer and the absorption axis of the linearly polarizing layer is 10° or more and 80°. the following.

[5] The display device according to any one of [1] to [4], wherein the in-plane retardation value of the first retardation layer at a wavelength of 550 nm is 80 nm or more and 170 nm or less.

[6] The display device according to [5], wherein the first retardation layer has reverse wavelength dispersion.

[7] The display device according to [5] or [6], further having a second retardation layer between the high refractive index layer and the linearly polarizing layer,

The above-mentioned second phase difference layer is laminated so as to cover the above-mentioned display element and the above-mentioned light-receiving sensor,

The thickness direction retardation value of the second retardation layer at a wavelength of 550 nm is -140 nm or more and -20 nm or less.

[8] The display device according to any one of [1] to [7], wherein the stimulus value Y of the reflected light when the light emitted from the display element is reflected by the high refractive index layer is 3.45% or more and 4.54 %the following.

[9] The display device according to any one of [1] to [8], wherein the light-receiving sensor can detect light having a wavelength of 320 nm or more and 4000 nm or less.

[10] The display device according to any one of [1] to [9], wherein the light emitted from the display element is light with a wavelength of 320 nm or more and 4000 nm or less.

[11] The display device according to any one of [1] to [10], further comprising a third retardation layer between the linearly polarizing layer and the display unit.

The present invention provides the following optical laminate.

[12] An optical laminate having a high refractive index layer, a first retardation layer, and a linear polarizing layer in this order,

The refractive index of the above-mentioned high refractive index layer is 1.60 or more.

[13] The optical laminate according to [12], wherein the first retardation layer covers the entire visible side of the linearly polarizing layer in plan view.

[14] The optical laminate according to [12] or [13], wherein the linearly polarizing layer has a visibility correction single transmittance of 42% or more.

[15] The optical laminate according to [12] or [13], wherein the angle formed by the slow axis of the first retardation layer and the absorption axis of the linearly polarizing layer is 10° or more and 80° or less.

[16] The optical laminate according to [12] or [13], wherein the in-plane retardation value of the first retardation layer at a wavelength of 550 nm is 80 nm or more and 170 nm or less.

[17] The optical laminate according to [12] or [13], wherein the first retardation layer has reverse wavelength dispersion.

[18] The optical laminate according to [12] or [13], further having a second retardation layer between the high refractive index layer and the linear polarizing layer,

The thickness direction retardation value of the second retardation layer at a wavelength of 550 nm is -140 nm or more and -20 nm or less.

[19] The optical laminate according to [12] or [13], further comprising a third retardation layer on the side of the linearly polarizing layer opposite to the first retardation layer.

Invention effect

According to the display device of the present invention, the reflected light reflected by the high refractive index layer can be prevented from entering the light-receiving sensor. Moreover, according to the optical laminated body of this invention, the above-mentioned display device of this invention can be provided.

Description of the drawings

FIG. 1 is a schematic cross-sectional view schematically showing a display device according to an embodiment of the present invention.

2 is a schematic cross-sectional view schematically showing a display device according to another embodiment of the present invention.

3 is a schematic cross-sectional view schematically showing a display device according to another embodiment of the present invention.

4 is a schematic cross-sectional view schematically showing a display device according to another embodiment of the present invention.

Detailed ways

Hereinafter, preferred embodiments of the display device and the optical laminate will be described with reference to the drawings. In each drawing, the same components as those described previously are denoted by the same reference numerals, and descriptions thereof are omitted.

[Embodiment 1]

(Display device and optical laminate)

1 and 2 are schematic cross-sectional views schematically showing a display device according to an embodiment of the present invention. In Figures 1 and 2, the upper side is the visible side. As shown in FIGS. 1 and 2 , the display devices 1 and 2 of this embodiment include a high refractive index layer 45 , a first phase difference layer 31 , a linear polarizing layer 11 and a display unit 40 in order from the viewing side. Among them, the high refractive index layer 45, the first retardation layer 31, and the linear polarizing layer 11 constitute the optical laminates 51 and 52. The refractive index of the high refractive index layer 45 is 1.60 or more, preferably 1.75 or more, more preferably 1.80 or more, usually 2.70 or less, preferably 2.40 or less, more preferably 2.30 or less, and still more preferably 2.10 or less. The refractive index of the high refractive index layer 45 can be measured by the method described in Examples described below.

The display unit 40 has a display element 41 and a light-receiving sensor 42 . As shown in FIGS. 1 and 2 , the display unit 40 may have a structure in which a light-receiving sensor 42 is stacked on the visible side of the display element 41 , or may have a structure in which a light-receiving sensor is stacked on the side opposite to the visible side of the display element 41 . 42 structure. Alternatively, the light-receiving sensor 42 may be embedded in a through hole or a recess provided in the display element 41 . In the display unit 40 , since the area of the display element 41 can be used as the display area of the display devices 1 and 2 , from the viewpoint of expanding the display area, in a plan view of the display unit 40 , it is preferable to surround the light-receiving sensor 42 . The area of the display element 41 is present in this manner.

In the display devices 1 and 2 , the first retardation layer 31 and the linear polarization layer 11 are laminated so as to cover the display element 41 and the light-receiving sensor 42 . The first retardation layer 31 and the linear polarization layer 11 are preferably laminated so as to cover the entire visible side of the display unit 40 , that is, to cover the entire visible side of the display element 41 and the light-receiving sensor 42 . By providing the linearly polarizing layer 11 as described above, the area of the display element 41 around the light-receiving sensor 42 is covered with the linearly polarizing layer 11 in a plan view, making it easy to expand the display areas of the display devices 1 and 2 . If the first phase difference layer 31 is laminated so as to cover the display element 41 and the light-receiving sensor 42, the entire linear polarizing layer 11 may be covered in plan view, or a part thereof may be covered. The plan view shape of the first retardation layer 31 may be the same as the plan view shape of the linearly polarizing layer 11 , or may be different.

In the display devices 1 and 2 , the light emitted from the display element 41 is used to display images. Part of the light emitted from the display element 41 may be reflected on the high refractive index layer 45 and enter the light-receiving sensor 42 as shown by the arrow in FIG. 1 . Particularly in a plan view of the display unit 40 , for example, when the area of the display element 41 is arranged around the light-receiving sensor 42 such that the light-receiving sensor 42 and the area of the display element 41 are adjacent to each other, the high refractive index The reflected light reflected by the layer 45 easily enters the light-receiving sensor 42 . Once reflected light enters the light-receiving sensor 42 , malfunction of the light-receiving sensor 42 is likely to occur. In the display devices 1 and 2 of this embodiment, the first retardation layer 31 is laminated on the visible side of the linear polarization layer 11 covering the display element 41 and the light-receiving sensor 42 . The reflected light reflected by the high refractive index layer 45 enters the first retardation layer 31 and passes through the first retardation layer 31, thereby changing the phase. Therefore, at least part of the reflected light passing through the first retardation layer 31 is easily absorbed by the linear polarization layer 11 . This makes it possible to reduce the amount of reflected light entering the light-receiving sensor 42 , thereby suppressing malfunction of the light-receiving sensor 42 .

The visibility correction single transmittance of the linearly polarizing layer 11 is preferably 42% or more, more preferably 43% or more, and may be 45% or more. If the visibility correction single transmittance of the linearly polarizing layer 11 increases, the amount of reflected light transmitted through the linearly polarizing layer 11 increases, so malfunction of the light-receiving sensor 42 is likely to occur. According to the display devices 1 and 2 of this embodiment, even when the linearly polarizing layer 11 having a large visibility correction single transmittance is used, the amount of reflected light incident on the light-receiving sensor 42 can be suppressed, thereby suppressing the light-receiving sensor 42 malfunction. The visibility correction single transmittance of the linearly polarizing layer 11 can be measured by the method described in Examples to be described later.

The first retardation layer 31 only needs to have a phase difference, and preferably has an in-plane phase difference value Re (550) at a wavelength of 550 nm of 80 nm or more and 170 nm or less. The in-plane retardation value Re (550) of the first retardation layer 31 is more preferably 100 nm or more, particularly preferably 130 nm or more, and may be 135 nm or more. In addition, it is more preferably 160 nm or less, further preferably 150 nm or less. The in-plane retardation value Re(550) of the first retardation layer 31 can be measured by the method described in Examples described later.

When the first phase difference layer 31 has the in-plane phase difference value Re (550) in the above range, the light emitted from the display element 41 in the display devices 1 and 2 is converted when it passes through the first phase difference layer 31 It is elliptically polarized light. The reflected light (elliptically polarized light) reflected by the high refractive index layer 45 passes through the first phase difference layer 31 and is converted into linearly polarized light. Thereby, the reflected light passing through the first retardation layer 31 is easily absorbed by the linearly polarizing layer 11 , so the amount of reflected light entering the light-receiving sensor 42 can be further suppressed.

When the in-plane retardation value Re (550) of the first retardation layer 31 is within the above range, the angle between the absorption axis of the linearly polarizing layer 11 and the slow axis of the first retardation layer 31 is preferably 10°. Above and below 80°. The above-mentioned angle may be 30° or more, and is more preferably 40° or more. In addition, the above-mentioned angle may be 60° or less, and is more preferably 50° or less.

The first retardation layer 31 whose in-plane retardation value Re (550) is in the above range preferably has reverse wavelength dispersion. As a result, the wavelength range of the reflected light absorbed by the linearly polarizing layer 11 becomes wider, so that the amount of reflected light of various wavelengths incident on the light-receiving sensor 42 can be suppressed.

In the display devices 1 and 2 , the stimulation value Y of the reflected light when the light emitted from the display element 41 is reflected by the high refractive index layer 45 is preferably 3.45% or more and 4.54% or less. The stimulus value Y of the reflected light is the ratio of the light intensity of the reflected light to the light intensity of the emitted light from the display element 41 . The smaller the stimulus value Y is, the smaller the amount of reflected light reflected by the high refractive index layer 45 is. , the less likely it is to cause malfunction of the light-receiving sensor 42 . The stimulation value Y of reflected light can be measured by the method described in the Examples described later. The stimulation value Y of the reflected light may be 3.48% or more, or may be 3.50% or more, and may be 4.30% or less, or 4.10% or less, 3.90% or less, or 3.76% or less.

In the display devices 1 and 2 in which the stimulation value Y of the emitted light is within the above-mentioned range, it is easy to suppress the amount of reflected light entering the light-receiving sensor 42 . When the stimulation value Y of the emitted light is smaller than the above range, it is considered that the refractive index of the high refractive index layer 45 is small or the visibility correction single transmittance of the linearly polarizing layer 11 is small. Therefore, it is considered that in a display device in which the stimulation value Y of the emitted light is smaller than the above range, the amount of reflected light incident on the light-receiving sensor 42 is small, and malfunction of the light-receiving sensor 42 is less likely to occur. In addition, in a display device in which the stimulation value Y of the emitted light is larger than the above range, the amount of reflected light incident on the light-receiving sensor 42 is large, and malfunction of the light-receiving sensor 42 is likely to occur.

(Layer structure of display device and optical laminate)

Next, layers that the display devices 1 and 2 and the optical laminates 51 and 52 may have in addition to the layers described above will be described.

As shown in FIGS. 1 and 2 , the display devices 1 and 2 and the optical laminates 51 and 52 preferably have the first bonding layer 21 between the high refractive index layer 45 and the first retardation layer 31 . The first bonding layer 21 may be in direct contact with the high refractive index layer 45 and the first retardation layer 31 .

The display devices 1 and 2 and the optical laminates 51 and 52 may have one or more second refractive index layers (not shown) in addition to the high refractive index layer 45 . The refractive index of the second refractive index layer can be the above-mentioned refractive index range described for the high refractive index layer 45 . The second refractive index layer may be provided on the visible side of the high refractive index layer 45 , or may be provided between the high refractive index layer 45 and the first retardation layer 31 . In this case, the display devices 1 and 2 and the optical laminates 51 and 52 may have an adhesive layer (a pressure-sensitive adhesive layer or adhesive layer to be described later) between the high refractive index layer 45 and the second refractive index layer, This bonding layer may be in direct contact with the high refractive index layer 45 and the second refractive index layer. When the display devices 1 and 2 and the optical laminates 51 and 52 have the second refractive index layer between the high refractive index layer 45 and the first retardation layer 31, the first bonding layer 21 may be different from the first retardation layer 31. Layer 31 and the second refractive index layer are in direct contact.

The display devices 1 and 2 and the optical laminates 51 and 52 preferably have the second bonding layer 22 between the first retardation layer 31 and the linear polarizing layer 11 . The second bonding layer 22 may be in direct contact with the first retardation layer 31 and the linear polarizing layer 11 .

The display devices 1 and 2 and the optical laminated bodies 51 and 52 may have the first protective film 12 between the first retardation layer 31 and the linear polarizing layer 11 as shown in FIGS. 1 and 2 . The first protective film 12 may be a layer for protecting the visible side surface of the linearly polarizing layer 11 , and the first protective film 12 and the linearly polarizing layer 11 may constitute a linearly polarizing plate. When the display devices 1 and 2 and the optical laminated bodies 51 and 52 have the first protective film 12 , the second bonding layer 22 may be in direct contact with the first retardation layer 31 and the first protective film 12 .

When the display devices 1 and 2 and the optical laminates 51 and 52 have the first protective film 12, the first protective film 12 and the linear polarizing layer 11 in the display devices 1 and 2 and the optical laminates 51 and 52 may be in direct contact. , however, it is preferable to have a third bonding layer 23 between the first protective film 12 and the linear polarizing layer 11 . The third bonding layer 23 can constitute a linear polarizing plate, and is preferably in direct contact with the first protective film 12 and the linear polarizing layer 11 .

The display devices 1 and 2 may have the fourth bonding layer 24 between the linearly polarizing layer 11 and the display unit 40 (the side of the linearly polarizing layer 11 opposite to the first retardation layer 31 side). The linear polarizing layer 11 and the display unit 40 may be in direct contact with the fourth bonding layer 24 as shown in FIG. 1 . As shown in FIGS. 1 and 2 , the fourth bonding layer 24 can be included in the optical laminates 51 and 52 .

The display devices 1 and 2 and the optical laminates 51 and 52 may have a second protective film (not shown) between the linearly polarizing layer 11 and the display unit 40 (the side of the linearly polarizing layer 11 opposite to the first retardation layer 31 side). icon). The second protective film may be a layer for protecting the surface of the linearly polarizing layer 11 on the side opposite to the visible side, and the second protective film and the linearly polarizing layer 11 may constitute a linearly polarizing plate. When the display devices 1 and 2 and the optical laminates 51 and 52 have a second protective film, the second protective film and the linearly polarizing layer 11 may be in direct contact or may have a second protective film between the second protective film and the linearly polarizing layer 11 . Adhesion layer (a pressure-sensitive adhesive layer or adhesive layer to be described later). This bonding layer can constitute a linear polarizing plate, and is preferably in direct contact with the second protective film and the linear polarizing layer 11 . In this case, the fourth bonding layer 24 may be provided between the second protective film and the display unit 40 , or may be in direct contact with the second protective film and the display unit 40 .

As shown in FIG. 2 , the display device 2 and the optical laminate 52 may have a third phase difference between the linearly polarizing layer 11 and the display unit 40 (the side of the linearly polarizing layer 11 opposite to the first phase difference layer 31 side). Layer 13. In this case, the display device 2 and the optical laminate 52 may have the fifth bonding layer 25 between the linearly polarizing layer 11 and the third retardation layer 13 , and the linearly polarizing layer 11 and the third retardation layer 13 may be connected to the fifth bonding layer 25 . The conforming layer 25 is in direct contact. When the display device 2 and the optical laminate 52 have the second protective film, the fifth bonding layer 25 is provided between the second protective film and the third retardation layer 13, and can be connected with the second protective film and the third phase difference layer 13. The difference layer 13 is in direct contact. In the display device 2 with the third phase difference layer 13, the fourth lamination layer 24 can be provided between the third phase difference layer 13 and the display unit 40, or can be directly connected to the third phase difference layer 13 and the display unit 40. touch. In the optical laminate 52 having the third retardation layer 13 , the fourth bonding layer 25 may be in direct contact with the third retardation layer 13 . The linear polarizing layer 11 and the third retardation layer 13 preferably constitute a circular polarizing plate, and the third retardation layer 13 is preferably a λ/4 retardation layer, and more preferably a λ/4 retardation layer with reverse wavelength dispersion.

The display device 2 and the optical laminate 52 may have the third retardation layer 13 between the linearly polarizing layer 11 and the display unit 40 (the side of the linearly polarizing layer 11 opposite to the first retardation layer 31 side). More than 4th phase difference layers (not shown). The fourth retardation layer may be provided between the linear polarization layer 11 and the third retardation layer 13, or may be provided between the third retardation layer 13 and the display unit 40 (the third retardation layer 13 and the linear polarization layer 11 opposite side). In this case, a bonding layer (an adhesive layer or an adhesive layer to be described later) may be provided between the third retardation layer 13 and the fourth retardation layer, and this bonding layer may be separated from the third retardation layer. The 13th and 4th phase difference layers are in direct contact. When the display device 2 and the optical laminate 52 have the fourth retardation layer between the linearly polarizing layer 11 and the third retardation layer 13 , the fifth bonding layer 25 may be separated from the linearly polarizing layer 11 and the fourth retardation layer. layers are in direct contact. When the display device 2 has the fourth retardation layer between the third retardation layer 13 and the display unit 40 , the fourth bonding layer 24 may be in direct contact with the fourth retardation layer and the display unit 40 . When the optical laminated body 52 has the third retardation layer on the side of the third retardation layer 13 opposite to the linear polarizing layer 11 side, the fourth retardation layer may be in direct contact with the fourth bonding layer. The linear polarizing layer 11, the third retardation layer 13, and the fourth retardation layer preferably constitute a circularly polarizing plate. The fourth retardation layer constituting the circularly polarizing plate is preferably a λ/2 retardation layer or a positive C layer.

[Embodiment 2]

3 and 4 are schematic cross-sectional views schematically showing a display device according to another embodiment of the present invention. In Figures 3 and 4, the upper side is the visible side. The display devices 3 and 4 and the optical laminates 53 and 54 of this embodiment have the second retardation layer 32 between the high refractive index layer 45 and the linear polarization layer 11. In this point, they are different from the display devices described in the previous embodiments. Since the devices 1 and 2 and the optical laminates 51 and 52 are different, this point will be described below.

In the display devices 3 and 4 , the second phase difference layer 32 is laminated so as to cover the display element 41 and the light-receiving sensor 42 . The second phase difference layer 32 is preferably laminated so as to cover the entire visible side of the display unit 40 , that is, to cover the entire visible side of the display element 41 and the light-receiving sensor 42 .

The display devices 3 and 4 and the optical laminates 53 and 54 shown in FIGS. 3 and 4 have the second retardation layer 32 between the high refractive index layer 45 and the first retardation layer 31 . The second retardation layer 32 preferably covers the entire first retardation layer 31 in plan view, and more preferably has the same plan view shape as the first retardation layer 31 .

The second retardation layer 32 only needs to have a retardation, but preferably has a thickness direction retardation value Rth (550) at a wavelength of 550 nm of -140 nm or more and -20 nm or less. The thickness direction phase difference value Rth (550) of the second retardation layer 32 may be greater than -140 nm, may be greater than -120 nm, may be greater than -100 nm, may be greater than -90 nm, and may be less than -20 nm, or may be It can be -30 or less, -40 or less, or -50 or less.

The thickness direction phase difference value Rth (550) of the second retardation layer 32 is a value calculated based on the formula (i).

Rth(550)＝[{(nx+ny)/2}-nz]×d (i)

[In formula (i),

nx is the main refractive index at a wavelength of 550 nm in the plane of the second retardation layer 32,

ny is the refractive index at a wavelength of 550nm in the same plane as nx and in the direction orthogonal to nx,

nz is the refractive index at a wavelength of 550 nm in the thickness direction of the second retardation layer 32. When nx=ny, nx can be the refractive index in any direction in the plane of the second retardation layer 32,

d is the film thickness of the second retardation layer 32 . ]

By providing the display devices 3 and 4 with the second phase difference layer 32 , as shown by the arrows in FIG. 3 , the amount of reflected light incident from an oblique direction among the reflected light incident on the light-receiving sensor 42 can be reduced. The reflected light incident from an oblique direction is mainly light emitted from a region of the display element 41 away from the light-receiving sensor 42 in a plan view of the display unit 40 and reflected by the high refractive index layer 45 . The amount of reflected light incident from an oblique direction is easily reduced when the thickness direction phase difference value Rth (550) of the second retardation layer 32 is in the above range. This can further suppress malfunction of the light-receiving sensor 42 .

As shown in FIGS. 3 and 4 , the first bonding layer 21 may be provided between the high refractive index layer 45 and the second phase difference layer 32 , or may be in direct contact with the high refractive index layer 45 and the second phase difference layer 32 . It is preferable that the display devices 3 and 4 and the optical laminates 53 and 54 have the sixth bonding layer 26 between the second retardation layer 32 and the first retardation layer 31, and the second retardation layer 32 and the first retardation layer 31. It is in direct contact with the sixth bonding layer 26 .

In the display devices 3 and 4 and the optical laminates 53 and 54 shown in FIGS. 3 and 4 , the case where the second retardation layer 32 is provided between the high refractive index layer 45 and the first retardation layer 31 was examined. However, as long as the second retardation layer 32 is provided between the high refractive index layer 45 and the linearly polarizing layer 11, the present invention is not limited to this. For example, the second retardation layer 32 may be provided between the first retardation layer 31 and the linear polarizing layer 11 . In this case, the second retardation layer 32 preferably covers the entire linear polarizing layer 11 . The plan view shape of the second retardation layer 32 is preferably the same as the plan view shape of the first retardation layer 31 .

When the display devices 3 and 4 and the optical laminates 53 and 54 have the second retardation layer 32 between the first retardation layer 31 and the linear polarizing layer 11, the display devices 3 and 4 and the optical laminates 53 and 54 You may have the 6th bonding layer 26 between the 2nd phase difference layer 32 and the 1st phase difference layer 31. In addition, the second bonding layer 22 may be provided between the second retardation layer 32 and the linear polarizing layer 11. For example, the second bonding layer 22 may be in direct contact with the second retardation layer 32 and the first protective film 12.

Hereinafter, the display device described above and the layers constituting the display device will be described in more detail.

(display device)

The above-mentioned display device can be used as a liquid crystal display device or an organic EL (electroluminescence) display device. The display device may be a portable terminal such as a smartphone or a tablet computer. The display device may be a flexible display capable of bending.

The top view outer shape of the display area of the display device is not particularly limited, and may be a rectangle, a square, a polygon other than a rectangle or a square, or a rounded shape in which the corners are rounded (having an R shape). A rectangular, square, polygonal, or rounded-shaped display area may have a through hole for arranging a camera or the like.

(display component)

The display element may be a liquid crystal display element or an organic EL display element. The liquid crystal display element may include, for example, a liquid crystal cell and a backlight in which a liquid crystal layer is sandwiched between two cell substrates. The organic EL display element may have a light-emitting layer, an electrode, etc., for example.

The light emitted from the display element is preferably light with a wavelength of 320 nm to 4000 nm, more preferably 380 nm to 780 nm (visible light range), and may be 380 nm to 720 nm.

(light sensor)

The light sensor detects incident light. The light-receiving sensor may be an illuminance sensor that detects illuminance around the display device, a proximity sensor that detects the approach of an object, or a sensor that constitutes a camera or the like. The light-receiving sensor is preferably capable of detecting light with a wavelength of 320 nm or more and 4000 nm or less, and more preferably can detect light with a wavelength of 380 nm or more and 780 nm or less (visible light range), and/or light with a wavelength of 780 nm or more and 4000 nm or less (infrared ray range).

(touch sensor panel)

The display device and the optical laminate may include a touch sensor panel. The touch sensor panel can detect the position touched by the user's finger or the like. Examples of the touch sensor panel include touch sensor panels of a resistive film type, a capacitive coupling type, a photosensor type, an ultrasonic type, an electromagnetic induction coupling type, a surface elastic wave type, etc. Among them, a resistive film type, Electrostatic capacitive coupling type touch sensor panel.

In the display device and the optical laminate, the touch sensor panel may be provided on the visible side of the linearly polarizing layer (the first retardation layer side of the linearly polarizing layer), or may be provided on the opposite side of the linearly polarizing layer from the visible side. side. When the touch sensor panel is provided on the visible side of the linear polarization layer, the touch sensor panel may constitute a high refractive index layer described below. In the case where the touch sensor panel is provided on the side of the linear polarization layer opposite to the visible side, the touch sensor panel is preferably provided between the linear polarization layer and the display unit.

(High refractive index layer)

The high refractive index layer is not particularly limited as long as the refractive index is within the range specified in this embodiment (1.60 or more). If the high refractive index layer has the above-mentioned refractive index, it may be a front panel of a display device or a touch sensor panel. The high refractive index layer may have a single-layer structure or a multi-layer structure. In the case where the high refractive index layer has a multi-layer structure, if the high refractive index layer has the above refractive index, the high refractive index layer may include a layer with a refractive index less than 1.60.

The front panel may constitute the frontmost part of the display device. The front panel only needs to be a plate-shaped body capable of transmitting light, and may be, for example, a resin plate, a resin film, a glass plate, a glass film, or the like. The front panel can be a single-layer structure or a multi-layer structure. The refractive index of the front panel may be 1.45 or more and 1.9 or less.

The polymer constituting the resin plate or the resin film is not particularly limited as long as it is a resin that can transmit light. Examples of such polymers include triacetylcellulose, cellulose acetobutyrate, ethylene-vinyl acetate copolymer, propionylcellulose, butyrylcellulose, levulinylcellulose, polyester, and polyphenylene. Ethylene, polyamide, polyetherimide, poly(meth)acrylic, polyimide, polyethersulfone, polysulfone, polyethylene, polypropylene, polymethylpentene, polyvinyl chloride, polyvinylidene Vinyl chloride, polyvinyl alcohol, polyvinyl acetal, polyether ketone, polyether ether ketone, polyether sulfone, polymethyl (meth)acrylate, polyethylene terephthalate, polyterephthalic acid Butylene glycol ester, polyethylene naphthalate, polycarbonate, polyamide-imide, etc. These polymers can be used individually or in mixture of 2 or more types. In this specification, (meth)acrylic means acrylic acid and/or methacrylic acid, and (meth)acrylic acid ester means acrylic acid ester and/or methacrylic acid ester.

When the front panel is a resin film, the front panel may have a hard coat layer on at least one surface of the resin film. The hard coat layer is, for example, a cured layer of ultraviolet curable resin. Examples of ultraviolet curable resins include monofunctional (meth)acrylic resins, polyfunctional (meth)acrylic resins, polyfunctional (meth)acrylic resins having a dendritic polymer structure (meth)acrylic resins, etc. ) Acrylic resin and other (meth)acrylic resin; silicone resin; polyester resin; urethane resin; amide resin; epoxy resin, etc. To increase strength, hardcoats can contain additives. The additive is not particularly limited, and examples thereof include inorganic fine particles, organic fine particles, or mixtures thereof. When the resin film has hard coat layers on both sides, the composition and thickness of each hard coat layer may be the same as each other or may be different from each other.

When the front panel is a glass plate or glass film, it is preferable to use tempered glass for displays.

Examples of the touch sensor panel constituting the high refractive index layer include the above-mentioned touch sensor panel. When the touch sensor panel constitutes the high refractive index layer, the refractive index of the touch sensor panel is 1.60 or more, preferably 1.70 or more, more preferably 1.90 or more, usually 2.70 or less, preferably 2.60 or less, and more preferably 2.40 or less.

(1st phase difference layer, 2nd phase difference layer, 3rd phase difference layer, 4th phase difference layer)

The first retardation layer, the second retardation layer, the third retardation layer, and the fourth retardation layer (hereinafter, these may be collectively referred to as "retardation layers") may be stretched films or may include polymerized films. A layer of a cured product layer of a liquid crystal compound.

When the retardation layer is a stretched film, a conventionally known stretched film may be used as the stretched film, and a stretched film in which a phase difference is provided by uniaxially stretching or biaxially stretching a resin film may be used. As the resin film, cellulose films such as triacetyl cellulose and diacetyl cellulose, polyethylene terephthalate, polyethylene isophthalate, polybutylene terephthalate, etc. can be used. Polyester film, polymethyl (meth)acrylate and poly(meth)ethyl acrylate and other acrylic resin films, polycarbonate film, polyethersulfone film, polysulfone film, polyimide film, polyolefin film , polynorbornene film, etc., but are not limited to them.

When the retardation layer is a stretched film, the thickness of the retardation layer is usually 5 μm or more and 200 μm or less, preferably 10 μm or more and 80 μm or less, and more preferably 40 μm or less.

When the retardation layer includes the above-described cured material layer, a conventionally known polymerizable liquid crystal compound can be used as the polymerizable liquid crystal compound. The polymerizable liquid crystal compound is a compound that has at least one polymerizable group and has liquid crystallinity.

The type of polymerizable liquid crystal compound is not particularly limited, and rod-shaped liquid crystal compounds, disk-shaped liquid crystal compounds, and mixtures thereof can be used. The cured material layer formed by polymerizing the polymerizable liquid crystal compound is cured in a state in which the polymerizable liquid crystal compound is oriented in an appropriate direction, thereby expressing a phase difference. When the rod-shaped polymerizable liquid crystal compound is oriented horizontally or vertically with respect to the plane direction of the display device, the optical axis of the polymerizable liquid crystal compound coincides with the long axis direction of the polymerizable liquid crystal compound. When a disc-shaped polymerizable liquid crystal compound is oriented, the optical axis of the polymerizable liquid crystal compound exists in a direction orthogonal to the disc surface of the polymerizable liquid crystal compound. As the rod-shaped polymerizable liquid crystal compound, for example, the polymerizable liquid crystal compound described in Japanese Patent Application Publication No. 11-513019 (claim 1, etc.) can be suitably used. As the disk-shaped polymerizable liquid crystal compound, Japanese Patent Application Laid-Open No. 2007-108732 (paragraphs [0020] to [0067], etc.) and Japanese Patent Application Laid-Open No. 2010-244038 ([0013] to [0108] can be suitably used. Polymerizable liquid crystal compounds described in paragraphs, etc.).

The polymerizable group contained in the polymerizable liquid crystal compound refers to a group that participates in a polymerization reaction, and is preferably a photopolymerizable group. The photopolymerizable group refers to a group that can participate in the polymerization reaction using active radicals, acids, etc. generated from the photopolymerization initiator. Examples of the polymerizable group include vinyl, vinyloxy, 1-chlorovinyl, isopropenyl, 4-vinylphenyl, (meth)acryloyloxy, epoxyethyl, and oxyheterocycle Butyl, styrene, allyl, etc. Among these, a (meth)acryloyloxy group, an vinyloxy group, an oxyethyl group, and an oxetanyl group are preferable, and an acryloyloxy group is more preferable. The liquid crystallinity of the polymerizable liquid crystal compound may be a thermotropic liquid crystal or a lyotropic liquid crystal. If the thermotropic liquid crystal is classified according to the degree of order, it may be a nematic liquid crystal or a smectic liquid crystal. liquid crystal. When two or more types of polymerizable liquid crystal compounds are used together to form a cured product layer of the polymerizable liquid crystal compound, it is preferred that at least one type has two or more polymerizable groups in the molecule. In this specification, the (meth)acryloyl group means an acryloyl group and/or a methacryloyl group.

When the retardation layer includes the above-mentioned cured material layer, the retardation layer may include an orientation layer. The alignment layer has an alignment regulating force that orients the polymerizable liquid crystal compound in a desired direction. The alignment layer may be a vertical alignment layer that orients the molecular axis of the polymerizable liquid crystal compound vertically with respect to the plane direction of the display device, or may be a horizontal alignment layer that orients the molecular axis of the polymerizable liquid crystal compound horizontally with respect to the plane direction of the display device. The alignment layer may be an oblique alignment layer in which the molecular axis of the polymerizable liquid crystal compound is obliquely aligned with respect to the plane direction of the display device. When the retardation layer includes two or more alignment layers, the alignment layers may be the same as each other or may be different from each other.

As the alignment layer, an alignment layer is preferably an alignment layer that has solvent resistance such that it will not be dissolved by application or the like of a liquid crystal layer forming composition containing a polymerizable liquid crystal compound, and has resistance to removal of a solvent and polymerization properties. Heat resistance of liquid crystal compounds during heat treatment of orientation. Examples of the alignment layer include an alignment polymer layer made of an alignment polymer, a photo-alignment polymer layer made of a photo-alignment polymer, and a groove having a concavo-convex pattern or a plurality of grooves on the surface of the layer. Groove orientation layer.

The above-mentioned cured material layer can be formed by applying a retardation layer-forming composition containing a polymerizable liquid crystal compound, a solvent, and various additives as necessary to the alignment layer to form a coating film. This coating film solidifies (hardens), thereby forming a cured product layer of the polymerizable liquid crystal compound. Alternatively, the composition may be applied on the base material layer to form a coating film, and the coating film may be stretched together with the base material layer to form a cured product layer. The above-mentioned composition may further contain a polymerization initiator, a reactive additive, a leveling agent, a polymerization inhibitor, etc., in addition to the above-mentioned polymerizable liquid crystal compound and solvent. Known substances such as the polymerizable liquid crystal compound, solvent, polymerization initiator, reactive additive, leveling agent, polymerization inhibitor, etc. can be used appropriately.

As the base material layer, a film formed of a resin material can be used. For example, a film using a resin material described as a thermoplastic resin for forming a first protective film to be described later can be used. The thickness of the base material layer is not particularly limited, but generally from the viewpoint of workability such as strength and operability, it is preferably 1 to 300 μm or less, more preferably 20 to 200 μm, and still more preferably 30 to 120 μm. The base material layer may be incorporated into the display device together with the cured product layer of the polymerizable liquid crystal compound, or the base material layer may be peeled off and only the cured product layer of the polymerizable liquid crystal compound, or the cured product layer and the alignment layer may be incorporated into the display device. . When the base material layer is incorporated into the display device together with the cured product layer of the polymerizable liquid crystal compound, the thickness of the base material layer may be less than 30 μm, for example, 25 μm or less.

When the retardation layer contains the above-mentioned cured material layer, the thickness of the retardation layer is preferably 0.1 μm or more, more preferably 0.2 μm or more, and is preferably 3 μm or less, more preferably 2 μm or less.

(Linear polarizing layer)

The linearly polarizing layer has the property of transmitting linearly polarized light having a vibration plane orthogonal to the absorption axis when unpolarized light is incident thereon. The linearly polarizing layer may be a polyvinyl alcohol-based resin film in which iodine is adsorbed and oriented (hereinafter sometimes referred to as a "PVA-based film"), or may be a film containing a compound having absorption anisotropy and liquid crystallinity. The composition is coated on a base film to form a liquid crystal polarizing layer film. The compound having absorption anisotropy and liquid crystallinity may be a mixture of a dye having absorption anisotropy and a compound having liquid crystallinity, or may be a dye having absorption anisotropy and liquid crystallinity.

The linearly polarizing layer is preferably a PVA-based film in which iodine is adsorbed and oriented. Examples of the linearly polarizing layer of the PVA-based film include PVA-based films such as polyvinyl alcohol films, partially formalized polyvinyl alcohol films, and ethylene-vinyl acetate copolymer-based partially saponified films that have been dyed with iodine. and stretched films, etc. If necessary, the PVA-based film to which iodine has been adsorbed and oriented by dyeing treatment may be treated with a boric acid aqueous solution, and then a cleaning step may be performed to rinse away the boric acid aqueous solution. Known methods can be used in each step.

Polyvinyl alcohol-based resin (hereinafter sometimes referred to as "PVA-based resin") can be produced by saponifying polyvinyl acetate-based resin. The polyvinyl acetate-based resin may be polyvinyl acetate, which is a homopolymer of vinyl acetate, or may be a copolymer of vinyl acetate and other monomers copolymerizable with vinyl acetate. Examples of other monomers copolymerizable with vinyl acetate include unsaturated carboxylic acids, olefins, vinyl ethers, unsaturated sulfonic acids, and acrylamide having an ammonium group.

The degree of saponification of PVA-based resin is usually about 85 to 100 mol%, preferably 98 mol% or more. The PVA-based resin may be modified. For example, polyvinyl formal, polyvinyl acetal, etc. modified with aldehydes may be used. The average degree of polymerization of PVA-based resin is usually about 1,000 to 10,000, preferably about 1,500 to 5,000. The saponification degree and average polymerization degree of PVA-based resin can be determined in accordance with JIS K 6726 (1994). If the average degree of polymerization is less than 1,000, it may be difficult to obtain preferable polarization performance, and if it exceeds 10,000, film processability may be poor.

The method for producing a linearly polarizing layer of a PVA-based film may include the steps of preparing a base film, applying a solution of a resin such as a PVA-based resin to the base film, drying to remove the solvent, etc., and drying the base film. A resin layer is formed on it. In addition, a primer layer may be formed in advance on the surface of the base film on which the resin layer is formed. As the base film, a film using a resin material described as a thermoplastic resin used to form a first protective film to be described later can be used. Examples of materials for the primer layer include resins obtained by cross-linking the hydrophilic resin used in the linearly polarizing layer.

Then, the amount of solvent such as water in the resin layer is adjusted as necessary, and then the base film and the resin layer are uniaxially stretched. Next, the resin layer is dyed with iodine to adsorb iodine to the resin layer and orient it. Then, if necessary, a cleaning process is performed in which the resin layer on which iodine is adsorbed and oriented is treated with a boric acid aqueous solution, and then the boric acid aqueous solution is rinsed away. Thereby, it is possible to produce a PVA-based film that is a resin layer in which iodine is adsorbed and oriented, that is, a linearly polarizing layer. Known methods can be used in each step.

The amount of boric acid in a boric acid-containing aqueous solution used to treat a PVA-based film or a resin layer to which iodine has been adsorbed and oriented is usually about 2 to 15 parts by mass per 100 parts by mass of water, preferably 5 to 12 parts by mass. share. The boric acid-containing aqueous solution preferably contains potassium iodide. The amount of potassium iodide in the boric acid-containing aqueous solution is usually about 0.1 to 15 parts by mass, preferably about 5 to 12 parts by mass per 100 parts by mass of water. The immersion time in the aqueous solution containing boric acid is usually about 60 to 1200 seconds, preferably about 150 to 600 seconds, and more preferably about 200 to 400 seconds. The temperature of the aqueous solution containing boric acid is usually 50°C or higher, preferably 50 to 85°C, and more preferably 60 to 80°C.

The uniaxial stretching of the PVA-based film, base film, and resin layer can be performed before dyeing, during dyeing, during boric acid treatment after dyeing, or in multiple stages of these. Uniaxial stretching. The PVA film, the base film, and the resin layer can be uniaxially stretched in the MD direction (film conveyance direction). In this case, uniaxial stretching can be performed between rollers with different peripheral speeds, or a hot roller can be used. Stretch in a uniaxial manner. In addition, the PVA-based film, the base film, and the resin layer can be uniaxially stretched in the TD direction (the direction perpendicular to the film conveyance direction). In this case, a so-called tenter method can be used. In addition, the above-mentioned stretching may be dry stretching in which the film is stretched in the air, or wet stretching in which the PVA-based film or the resin layer is stretched with a solvent in a swollen state. In order to express the performance of the linear polarizing layer, the stretching ratio is 4 times or more, preferably 5 times or more, and particularly preferably 5.5 times or more. The upper limit of the stretch ratio is not particularly limited, but from the viewpoint of suppressing breakage, it is preferably 8 times or less.

The linear polarizing layer produced by a manufacturing method using a base film can be obtained by laminating a first protective film or a second protective film and then peeling off the base film. According to this method, the linear polarizing layer can be further thinned.

The thickness of the linearly polarizing layer of the PVA-based film is preferably 1 μm or more, may be 2 μm or more, may be 5 μm or more, and is preferably 30 μm or less, more preferably 15 μm or less, may be 10 μm or less, or may be 8 μm. the following.

Examples of films containing a liquid crystalline polarizing layer include coating a base film with a composition containing a pigment having liquid crystallinity and absorption anisotropy, or a composition containing a pigment having absorption anisotropy and polymerizable liquid crystal. The obtained linear polarizing layer. Examples of the base film include a film using a resin material described as a thermoplastic resin used to form a first protective film described below. Examples of the film including a liquid crystal polarizing layer include the polarizing layer described in Japanese Patent Application Laid-Open No. 2013-33249 and the like.

It is preferable that the total thickness of the base film and the linear polarizing layer formed as described above is small. However, if it is too small, the strength will be reduced and the processability will tend to be poor. Therefore, it is usually 20 μm or less, preferably 5 μm or less, and more preferably 0.5 to 3 μm. .

The linearly polarizing layer (PVA-based film, film containing a liquid crystalline polarizing layer) obtained as described above may have a first protective film and/or a second protective film described later laminated via an adhesive on one or both surfaces thereof. The linear polarizing plate of the film is installed into the display device. In a film including a liquid crystal polarizing layer, the above-mentioned base film can be used as a first protective film or a second protective film.

(1st protective film, 2nd protective film)

As the first protective film and the second protective film, for example, a film made of a thermoplastic resin excellent in transparency, mechanical strength, thermal stability, water barrier properties, isotropy, stretchability, and the like is used. Specific examples of the thermoplastic resin include cellulose resins such as triacetyl cellulose; polyester resins such as polyethylene terephthalate and polyethylene naphthalate; polyethersulfone resin; polysulfone resin. ; Polycarbonate resin; Polyamide resin such as nylon and aromatic polyamide; Polyimide resin; Polyolefin resin such as polyethylene, polypropylene, ethylene-propylene copolymer; Ring system and norbornene structure Polyolefin resin (also called norbornene resin); (meth)acrylic resin; polyarylate resin; polystyrene resin; polyvinyl alcohol resin and mixtures thereof. The resin compositions of the first protective film and the second protective film may be the same or different.

The first protective film may be a film having anti-reflective properties, anti-glare properties, hard-coat properties, or the like (hereinafter, a protective film having such properties may be referred to as a “functional protective film”). When the first protective film is not a functional protective film, a surface functional layer such as an antireflection layer, an antiglare layer, and a hard coat layer may be provided on one side of the linearly polarizing plate. The surface functional layer is preferably provided in direct contact with the first protective film. The surface functional layer is preferably provided on the side of the first protective film opposite to the linear polarizing layer side.

The first protective film and the second protective film are each independently preferably 3 μm or more, more preferably 5 μm or more, and preferably 50 μm or less, more preferably 30 μm or less.

(1st bonding layer, 2nd bonding layer, 3rd bonding layer, 4th bonding layer, 5th bonding layer, 6th bonding layer)

The first bonding layer, the second bonding layer, the third bonding layer, the fourth bonding layer, the fifth bonding layer, the sixth bonding layer, and the bonding layer (hereinafter, they may be collectively referred to as "laminated layers"). "laminated layer".) are each independently an adhesive layer or an adhesive layer.

When the bonding layer is an adhesive layer, it is an adhesive layer formed using an adhesive composition. An adhesive composition or a reaction product of an adhesive composition is a substance that exhibits adhesiveness by sticking itself to an adherend such as a metal layer, and is a so-called pressure-sensitive adhesive. . In addition, the crosslinking degree and adhesive force of the adhesive layer formed using the active energy ray-curable adhesive composition described later can be adjusted by irradiating active energy rays.

As the adhesive composition, conventionally known adhesives excellent in optical transparency can be used without particular limitation. For example, adhesives containing acrylic polymers, urethane polymers, silicone polymers, and polyvinyl ethers can be used. Adhesive compositions based on polymers. In addition, the adhesive composition may be an active energy ray-curable adhesive composition, a thermosetting adhesive composition, or the like. Among them, an adhesive composition using an acrylic resin as a base polymer that is excellent in transparency, adhesive strength, re-peelability (reworkability), weather resistance, heat resistance, etc. is suitable. The adhesive layer is preferably composed of a reaction product of an adhesive composition containing a (meth)acrylic resin, a cross-linking agent, and a silane compound, and may contain other components.

The adhesive layer can be formed using an active energy ray-curable adhesive. Regarding active energy ray-curable adhesives, a UV-curable compound such as a polyfunctional acrylate is blended with the above-mentioned adhesive composition, and after the adhesive layer is formed, ultraviolet rays are irradiated to cure the adhesive layer. Hard adhesive layer. Active energy ray-curable adhesives have the property of being cured upon exposure to energy rays such as ultraviolet rays and electron beams. The active energy ray-curable adhesive has adhesive properties even before energy ray irradiation, so it adheres closely to the adherend, and has the property of being able to adjust the adhesion force by being cured by energy ray irradiation.

The thickness of the adhesive layer is not particularly limited, but is preferably 5 μm or more, may be 10 μm or more, may be 15 μm or more, may be 20 μm or more, may be 25 μm or more, and is usually 300 μm or less, may be 250 μm or less, It may be 100 μm or less, or it may be 50 μm or less.

When the bonding layer is an adhesive layer, the adhesive layer can be formed by curing the curable component in the adhesive composition. The adhesive composition for forming the adhesive layer is an adhesive other than a pressure-sensitive adhesive (adhesive), and examples thereof include a water-based adhesive and an active energy ray-curable adhesive. .

Examples of the water-based adhesive include an adhesive obtained by dissolving or dispersing polyvinyl alcohol resin in water. The drying method when using a water-based adhesive is not particularly limited. For example, a drying method using a hot air dryer or an infrared dryer can be used.

Examples of active energy ray-curable adhesives include solvent-free active energy ray-curable adhesives containing a curable compound that is cured by irradiation with active energy rays such as ultraviolet light, visible light, electron beams, and X-rays. Recipient. By using a solvent-free active energy ray-curable adhesive, the adhesion between layers can be improved.

The active energy ray-curable adhesive preferably contains any one or both of a cationically polymerizable curable compound and a radical polymerizable curable compound from the viewpoint of exhibiting good adhesiveness. The active energy ray-curable adhesive may further contain a cationic polymerization initiator such as a photocationic polymerization initiator or a radical polymerization initiator for initiating the curing reaction of the curable compound.

Examples of the cationically polymerizable curable compound include an alicyclic epoxy compound having an epoxy group bonded to an alicyclic ring, and a polyfunctional aliphatic compound having two or more epoxy groups and not having an aromatic ring. Family epoxy compounds, monofunctional epoxy groups with one epoxy group (excluding epoxy groups included in alicyclic epoxy compounds), polyfunctional epoxy groups with two or more epoxy groups and aromatic rings Epoxy compounds such as functional aromatic epoxy compounds; oxetane compounds having one or more oxetane rings in the molecule; and combinations thereof.

Examples of radically polymerizable curable compounds include (meth)acrylic compounds (compounds having one or more (meth)acryloyloxy groups in the molecule), radically polymerizable curable compounds, other vinyl compounds with double bonds, or combinations thereof.

The active energy ray-curable adhesive may contain a sensitizer such as a photosensitizer if necessary. By using a sensitizer, the reactivity is improved, and the mechanical strength and adhesive strength of the adhesive layer can be further improved. Known sensitizers can be used appropriately as the sensitizer. When a sensitizer is blended, the blending amount is preferably in the range of 0.1 to 20 parts by mass relative to 100 parts by mass of the total amount of the active energy ray-curable adhesive.

The active energy ray curable adhesive may contain ion trapping agents, antioxidants, chain transfer agents, tackifiers, thermoplastic resins, fillers, flow regulators, plasticizers, defoaming agents, antistatic agents, flow regulators, etc. as needed. Leveling agents, solvents and other additives.

When an active energy ray-curable adhesive is used, active energy rays such as ultraviolet light, visible light, electron beams, and X-rays can be irradiated to cure the coating layer of the adhesive to form an adhesive layer. As the active energy ray, ultraviolet rays are preferred. As the light source in this case, low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, chemical lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, etc. can be used.

When the bonding layer is an adhesive layer, the thickness is preferably 0.1 μm or more, and may be 0.5 μm or more, and is preferably 10 μm or less, and may be 5 μm or less.

Example

Hereinafter, examples will be given to further explain the present invention in detail. However, the present invention is not limited to these examples.

[Measurement of refractive index]

The refractive index of the high refractive index layer was measured using a multi-wavelength Abbe refractometer ["DR-M4" manufactured by ATAGO Co., Ltd.] in a 25° C. environment with the measurement wavelength set to 589 nm.

[Measurement of visibility-corrected monomer transmittance Ty]

For the linearly polarizing layer, the MD transmittance and TD transmittance in the wavelength range of 380 to 780 nm were measured using a spectrophotometer with an integrating sphere ["V7100" manufactured by JASCO Corporation], and the values at each wavelength were calculated based on the following formula The monomer transmittance:

Monomer transmittance (%)=(MD+TD)/2

The "MD transmittance" is the transmittance when the direction of the polarized light emitted from the Glan-Thomson prism is parallel to the transmission axis of the linearly polarizing layer, and is expressed as "MD" in the above formula. In addition, the "TD transmittance" is the transmittance when the direction of the polarized light emitted from the Glan-Thomson prism is orthogonal to the transmission axis of the linearly polarizing layer, and is expressed as "TD" in the above formula. The obtained single transmittance was obtained by performing visibility correction using the 2-degree field of view (C light source) of JIS Z 8701:1999 "Method of Expression of Color - XYZ Color System and X ₁₀ Y ₁₀ Z ₁₀ Color System" Visibility corrected monomer transmittance.

[Measurement of in-plane phase difference values]

The in-plane retardation value of the first retardation layer and the first protective film was measured using a retardation measuring device (KOBRA-WPR manufactured by Oji Scientific Instruments Co., Ltd.).

[Measurement of phase difference value in thickness direction]

The thickness direction phase difference value of the second phase difference layer was measured using a phase difference measuring device (KOBRA-WPR manufactured by Oji Scientific Instruments Co., Ltd.). In the measurement, the incident angle of light toward the second retardation layer was changed, and the front retardation value of the second retardation layer and the retardation value when tilted at 40° about the fast axis were measured. The average refractive index at each wavelength was measured using an ellipsometer M-220 manufactured by JASCO Corporation. In addition, the thickness of the second retardation layer was measured using Optical NanoGauge film thickness meter C12562-01 manufactured by Hamamatsu Photonics Co., Ltd. Based on the front retardation value measured above, the retardation value when tilted at 40° with the fast axis as the center, the average refractive index, and the thickness of the second retardation layer, Oji Instruments Technical Data (https:// oji-keisoku.co.jp/cms/uploads/kbr_shiryo04.pdf) is used as a reference to calculate the three-dimensional refractive index. Based on the obtained three-dimensional refractive index, the thickness direction retardation value Rth of the second retardation layer is calculated according to the above-mentioned formula (i).

[Measurement of stimulation value Y]

To measure the stimulation value Y, a spectrophotometer [CM2600d manufactured by Konica Minolta] was used. Light was incident on the spectrophotometer from the moth eye mask side of the laminate, and the stimulus value Y of the reflected light was measured. It should be noted that since the reflectivity of the moth eye film is very small, the influence of the interface reflection between the air and the moth eye film of the light from the spectrophotometer can be ignored. During measurement, confirm that there is no light-reflective object within 1 m of the light traveling direction relative to the light-receiving and emitting portion of the spectrophotometer, and perform the measurement in a sufficiently dark environment to eliminate the influence of external light. In this measurement environment, measurement with a spectrophotometer was performed without the measurement sample (laminated body). As a result, it was confirmed that the stimulation value Y was 0.1% or less. Therefore, when the stimulation value Y of the laminate is measured under the above-mentioned measurement environment, part of the light detected by the spectrophotometer is absorbed by the polarizing plate, and only the light is reflected by the high refractive index layer.

[Example 1]

(Production of polarizing plate (1))

A polyvinyl alcohol-based resin film with a thickness of 20 μm (average degree of polymerization is about 2400, degree of saponification is 99.9 mol% or more) was uniaxially stretched in the longitudinal direction by dry stretching at a draw ratio of about 4.5 times. Keep the tensioned state unchanged after stretching, and immerse it in pure water at a temperature of 30°C for 60 seconds. Next, while maintaining the tensioned state, it was immersed for 60 seconds in an iodine/potassium iodide aqueous solution with a mass ratio of iodine/potassium iodide/water of 0.05/5/100 and a temperature of 28°C. Next, while maintaining the tensioned state, it was immersed in a potassium iodide/boric acid aqueous solution with a mass ratio of potassium iodide/boric acid/water of 15/5.5/100 and a temperature of 64°C for 170 seconds. Next, while maintaining the tension, wash with pure water at a temperature of 10°C for 5 seconds. Next, while maintaining the tension, dry at 80°C for 70 seconds in the air to adsorb iodine to the polyvinyl alcohol-based resin film. This was oriented to produce a polarizing plate (1) (linearly polarizing layer) with a thickness of 8 μm. The visibility correction single transmittance Ty of this polarizing plate (1) is 42.2±0.5%.

(Preparation of the first phase difference layer (1))

A cyclic polyolefin resin film having a hard coat layer and a thickness of 25 μm was prepared as the first retardation layer (1). The in-plane phase difference value of the first retardation layer (1) at a wavelength of 550 nm is 100 nm.

(Preparation of water-based adhesive)

Dissolve 3 parts by mass of carboxyl-modified polyvinyl alcohol ["KL-318" manufactured by Kuraray Co., Ltd.] in 100 parts by mass of water to obtain a polyvinyl alcohol aqueous solution, and add the water-soluble polyvinyl alcohol to the aqueous polyvinyl alcohol solution (100 parts by mass of water). 1.5 parts by mass of a flexible polyamide epoxy resin ["Sumirez Resin 650 (30)" manufactured by Tagoka Chemical Industry Co., Ltd., solid content concentration: 30% by mass] (solid content: 0.45 parts by mass) was used to obtain a water-based adhesive.

(Production of linear polarizing plate (1))

A cyclic polyolefin resin film with a thickness of 13 μm was prepared as the first protective film. In addition, a triacetylcellulose-based resin film ("KC4UY" manufactured by Konica Minolta Co., Ltd., thickness 40 μm) whose surface was not saponified was prepared as a second protective film.

On one side of the polarizing plate (1) obtained above, the first protective film (cyclic polyolefin resin film) prepared above is laminated via the water-based adhesive obtained above, and on the other side of the polarizing plate (1) The second protective film (triacetyl cellulose-based resin film) prepared above was laminated on the surface through pure water, passed between a pair of laminating rollers, and then heated and dried at a temperature of 85°C for 3 minutes to achieve water-based bonding. The agent is cured to form an adhesive layer as the third bonding layer, and a linear polarizing plate (1) having a layer structure of first protective film/third bonding layer/polarizing plate (1)/second protective film is produced. . The in-plane phase difference value of the first protective film at a wavelength of 550 nm is 0 nm.

(Preparation of high refractive index layer)

On one surface of an alkali-free glass plate ("Eagle XG" manufactured by Corning Corporation, refractive index 1.50), a film of ITO (Indium Tin Oxide), which is a mixture of indium oxide and tin oxide, is formed by vacuum evaporation to a thickness of 100 μm. ITO layer, a high refractive index layer which is a laminated structure of an alkali-free glass plate and an ITO layer is obtained. The refractive index of this high refractive index layer was measured from the ITO layer side, and the result was 2.00.

(Production of laminated body (1))

Then, the second protective film was peeled off from the linear polarizing plate (1), and a moth-eye mask (manufactured by GEOMATEC) was laminated on the exposed polarizing plate (1) side via the fourth bonding layer (acrylic adhesive layer with a thickness of 25 μm). .moth), on the first protective film side of the linear polarizing plate (1), the second laminating layer (acrylic adhesive layer with a thickness of 5 μm), the first retardation layer (1), and the first laminating layer are sequentially laminated. layer (acrylic adhesive layer with a thickness of 25 μm), a laminated structure (refractive index 2.00) of an alkali-free glass plate with a refractive index of 1.50 (Eagle XG, refractive index 1.50) and a high refractive index layer (ITO layer), black acrylic board (アクリル board) to produce a laminated body (1). The laminated body (1) is laminated so that the high refractive index layer is on the black acrylic plate side. The space between the high refractive index layer and the black acrylic plate was filled with ethanol dropped before lamination to eliminate the air layer. The first retardation layer (1) is laminated such that the hard coat layer side is the high refractive index layer side. In the laminate (1), the angle formed by the slow axis of the first retardation layer (1) and the absorption axis of the polarizing plate (1) of the linearly polarizing plate (1) is 45°. The layer structure of the obtained laminate (1) is black acrylic plate/ethanol/high refractive index layer/first bonding layer/first retardation layer (1)/second bonding layer/first protective film/third Laminating layer/polarizing plate (1)/4th laminating layer/moth eye mask. Table 1 shows the results obtained by measuring the stimulation value Y of the laminate (1). The moth eye film is a film designed to evaluate the laminate (1) while ignoring the influence of interface reflection between the fourth bonding layer and the air layer. In an actual display device, the difference between the fourth bonding layer and the air layer is A display unit is arranged on the opposite side of the polarizing plate (1).

[Example 2]

(Preparation of the first phase difference layer (2))

A cyclic polyolefin resin film with a thickness of 50 μm was prepared as the first retardation layer (2). The in-plane phase difference value of the first retardation layer (2) at a wavelength of 550 nm is 141 nm.

(Production of laminated body (2))

A laminated body (2) was obtained in the same procedure as in Example 1, except that the first retardation layer (2) was used instead of the first retardation layer (1). The layer structure of the obtained laminate (2) is black acrylic plate/ethanol/high refractive index layer/first bonding layer/first retardation layer (2)/second bonding layer/first protective film/third Laminating layer/polarizing plate (1)/4th laminating layer/moth eye mask. Table 1 shows the results obtained by measuring the stimulation value Y of the laminate (2).

[Example 3]

(Preparation of horizontal alignment film forming composition)

Horizontal alignment was obtained by mixing 5 parts by mass of a photo-alignment polymer with the following structure (described in Japanese Patent Application Laid-Open No. 2013-33249) and 95 parts by mass of cyclopentanone (solvent), and stirring at a temperature of 80° C. for 1 hour. Film-forming composition.

·Photo-alignment polymer (5 parts by mass):

[Chemical formula 1]

·Solvent (95 parts by mass): cyclopentanone

(Preparation of polymerizable liquid crystal composition (A1) for forming the first retardation layer (3))

The polymerizable liquid crystal compound (X1) and the polymerizable liquid crystal compound (X2) were mixed at a mass ratio of 90:10 to obtain a mixture. 0.1 part of the leveling agent "BYK-361N" (manufactured by BM Chemie) and 2-dimethylamino-2-benzyl-1-(4-methyl) as a photopolymerization initiator were added to 100 parts of the obtained mixture. 6 parts of phylinophenyl)-1-butanone ("Irgacure (registered trademark) 369 (Irg369)" manufactured by BASF JAPAN Co., Ltd.). Next, N-methyl-2-pyrrolidone (NMP) was added so that the solid content concentration would be 13%. This mixture was stirred at 80° C. for 1 hour, thereby obtaining a polymerizable liquid crystal composition (A1) for forming the first retardation layer (3).

Polymerizable liquid crystal compound (X1):

[Chemical formula 2]

Polymerizable liquid crystal compound (X2):

[Chemical formula 3]

(Preparation of the first phase difference layer (3))

After corona treatment was performed on the COP (cyclic olefin resin) film (ZF-14-50) manufactured by Japan ZEON Co., Ltd., the horizontal alignment film forming composition obtained above was coated with a bar coater, and the composition was coated at 80 °C for 1 minute, and using a polarized UV irradiation device (SPOT CURE SP-9; manufactured by USHIO Denki Co., Ltd.), polarized UV exposure was performed under the condition that the cumulative light amount at a wavelength of 313 nm: 100 mJ/cm ² to obtain a horizontal alignment film. The film thickness of the obtained horizontal alignment film was measured using an ellipsometer, and the result was 200 nm.

Next, the polymerizable liquid crystal composition (A1) obtained above was coated on the horizontal alignment film using a bar coater, and after heating at 120° C. for 60 seconds, a high-pressure mercury lamp (UNICURE VB-15201BY-A, USHIO Electric Co., Ltd. ( ^manufactured by cured product layer) to obtain a laminated structure (A1) having a layer structure of COP film/horizontal alignment film/horizontal alignment liquid crystal layer. After confirming that there is no retardation in the COP film, the in-plane retardation values Re (450) and Re (550) of the first retardation layer (3) were measured at a wavelength of 450 nm and a wavelength of 550 nm of the laminated structure (A1). In-plane phase difference values Re(450) and Re(550), Re(550) is 139nm. Re(450)/Re(550) was calculated and the result was 0.87. Therefore, it was confirmed that the laminate showed reverse wavelength dispersion.

The COP film of the laminated structure (A1) was peeled off, and the horizontal alignment film/horizontal alignment liquid crystal layer was used as the first retardation layer (3).

(Production of laminated body (3))

A laminated body (3) was obtained in the same procedure as in Example 1, except that the first retardation layer (3) was used instead of the first retardation layer (1). The first retardation layer (3) is stacked such that the horizontal alignment film side is the high refractive index layer side. The layer structure of the obtained laminate (3) is black acrylic plate/ethanol/high refractive index layer/first bonding layer/first retardation layer (3)/second bonding layer/first protective film/third Laminating layer/polarizing plate (1)/4th laminating layer/moth eye mask. Table 1 shows the results obtained by measuring the stimulation value Y of the laminate (3).

[Example 4]

(Preparation of vertical alignment film forming composition)

Silane coupling agent "KBE-9103" (manufactured by Shin-Etsu Chemical Industry Co., Ltd.) was dissolved in a mixed solvent of ethanol and water in a ratio of 9:1 (weight ratio) to obtain vertical alignment with a solid content concentration of 1%. Film-forming composition.

(Preparation of polymerizable liquid crystal composition (A2) for forming the second retardation layer (1))

To 100 parts of Paliocolor LC242 (registered trademark of BASF Corporation) which is a polymerizable liquid crystal compound, 0.1 part of F-556 as a leveling agent and 3 parts of Irgacure 369 as a polymerization initiator were added. Cyclopentanone was added so that the solid content concentration became 13%, and the polymerizable liquid crystal composition (A2) was obtained.

(Preparation of the second phase difference layer (1))

After corona treatment was performed on the COP (cyclic olefin resin) film (ZF-14-50) manufactured by Nippon ZEON Co., Ltd., the vertical alignment film forming composition was applied with a bar coater and dried at 120°C for 1 minute. , to obtain a vertically oriented film. The film thickness of the obtained vertical alignment film was measured using an ellipsometer, and the result was 100 nm.

Next, the polymerizable liquid crystal composition (A2) obtained above was applied to the vertical alignment film using a coater, and after drying at 120° C. for 1 minute, a high-pressure mercury lamp (UNICURE VB-15201BY-A, USHIO Electric Co., Ltd. ( ^manufactured by cured product layer) to obtain a laminated structure (A2) having a layer structure of COP film/vertical alignment film/vertical alignment liquid crystal layer. After confirming that there is no retardation in the COP film, the thickness direction retardation value Rth (550) of the second retardation layer (1) is measured as the thickness direction retardation value Rth (550) of the laminated structure (A2) at a wavelength of 550 nm. ), the result is that Rth(550) is -70nm.

The COP film and the vertical alignment film of the laminated structure (A2) were peeled off, and the vertical alignment liquid crystal layer was used as the second retardation layer (1).

(Production of laminated body (4))

The horizontal alignment liquid crystal layer side of the first retardation layer (3) produced by the same procedure as in Example 3 was bonded to the second retardation layer (1) using an ultraviolet curable adhesive. The agent was cured to form an adhesive layer (thickness 1 μm) as the sixth bonding layer, and a retardation laminate of the second retardation layer (1)/the sixth bonding layer/the first retardation layer (3) was produced. .

A laminated body (4) was obtained in the same manner as in Example 1, except that a retardation laminate was used instead of the first retardation layer (1). The retardation laminated body is laminated|stacked so that the 2nd retardation layer (1) side may be a high refractive index layer (1) side. The layer structure of the obtained laminate (4) is black acrylic plate/ethanol/high refractive index layer/first bonding layer/second retardation layer (1)/sixth bonding layer/first retardation layer (3) )/2nd laminating layer/1st protective film/3rd laminating layer/polarizing plate (1)/4th laminating layer/moth eye mask. Table 1 shows the results obtained by measuring the stimulation value Y of the laminate (4).

Table 1

[Example 5]

(Preparation of polarizing plate (2))

A polyvinyl alcohol-based resin film with a thickness of 20 μm (average degree of polymerization: 2400, degree of saponification: 99.9 mol% or more) was uniaxially stretched in the longitudinal direction by dry stretching at a stretching ratio of about 4.5 times. Keep the tensioned state unchanged after stretching, and immerse it in pure water at a temperature of 30°C for 60 seconds. Next, while maintaining the tensioned state, it was immersed for 60 seconds in an iodine/potassium iodide aqueous solution with a mass ratio of iodine/potassium iodide/water of 0.02/5/100 and a temperature of 28°C. Next, while maintaining the tensioned state, it was immersed in a potassium iodide/boric acid aqueous solution with a mass ratio of potassium iodide/boric acid/water of 15/5.5/100 and a temperature of 64°C for 45 seconds. Next, while maintaining the tension, wash with pure water at a temperature of 10°C for 5 seconds. Next, while maintaining the tension, dry at 80°C for 75 seconds in the air to adsorb iodine to the polyvinyl alcohol-based resin film. This was oriented to produce a polarizing plate (2) (linearly polarizing layer) with a thickness of 8 μm. The visibility correction single transmittance Ty of the polarizing plate (2) is 46.0±0.5%.

(Production of laminated body (5))

Except using the polarizing plate (2) instead of the polarizing plate (1), the laminated body (5) was obtained by the same procedure as Example 1. The layer structure of the obtained laminate (5) is black acrylic plate/ethanol/high refractive index layer/first bonding layer/first retardation layer (1)/second bonding layer/first protective film/third Laminating layer/polarizing plate (2)/4th laminating layer/moth eye mask. Table 2 shows the results obtained by measuring the stimulation value Y of the laminate (5).

[Example 6]

Except using the polarizing plate (2) instead of the polarizing plate (1), the laminated body (6) was obtained by the same procedure as Example 2. The layer structure of the obtained laminate (6) is black acrylic plate/ethanol/high refractive index layer/first bonding layer/first retardation layer (2)/second bonding layer/first protective film/third Laminating layer/polarizing plate (2)/4th laminating layer/moth eye mask. Table 2 shows the results obtained by measuring the stimulation value Y of the laminate (6).

[Example 7]

A laminated body (7) was obtained in the same procedure as in Example 3, except that the polarizing plate (2) was used instead of the polarizing plate (1). The layer structure of the obtained laminate (7) is black acrylic plate/ethanol/high refractive index layer/first bonding layer/first retardation layer (3)/second bonding layer/first protective film/third Laminating layer/polarizing plate (2)/4th laminating layer/moth eye mask. Table 2 shows the results obtained by measuring the stimulation value Y of the laminate (7).

[Example 8]

Except using the polarizing plate (2) instead of the polarizing plate (1), the laminated body (8) was obtained by the same procedure as Example 4. The layer structure of the obtained laminate (8) is black acrylic plate/ethanol/high refractive index layer/first bonding layer/second retardation layer (1)/sixth bonding layer/first retardation layer (3) )/2nd laminating layer/1st protective film/3rd laminating layer/polarizing plate (2)/4th laminating layer/moth eye mask. Table 2 shows the results obtained by measuring the stimulation value Y of the laminate (8).

[Comparative example 1]

A laminate (( 9). The layer structure of the obtained laminate (9) is black acrylic plate/ethanol/high refractive index layer/first laminating layer/first protective film/third laminating layer/polarizer (2)/fourth laminating layer /moth eye mask. Table 2 shows the results obtained by measuring the stimulation value Y of the laminate (9).

[Table 2

From the results shown in Table 1 and Table 2, it can be seen that when the in-plane retardation value of the first retardation layer is in the range of 80 nm or more and 170 nm or less, the stimulation value Y becomes smaller, and the radiation incident on the light receiving element of the display unit can be reduced. reflected light. In addition, it was found that even when the visibility correction unit transmittance Ty of the polarizing plate included in the laminate is large, the stimulation value Y can be reduced and the reflected light incident on the light receiving element of the display unit can be reduced.

Explanation of reference signs

1 to 4 display device, 11 linear polarizing layer, 12 1st protective film, 13 3rd retardation layer, 21 1st laminating layer, 22 2nd laminating layer, 23 3rd laminating layer, 24 4th laminating layer Layer, 25 5th laminating layer, 26 6th laminating layer, 31 1st phase difference layer, 32 2nd phase difference layer, 40 display unit, 41 display element, 42 light receiving sensor, 45 high refractive index layer, 51～ 54 optical laminate.

Claims (19)

1. A display device, which is used for displaying a display image,

which comprises a high refractive index layer, a 1 st phase difference layer, a linear polarization layer and a display unit in order from the visual side,

the high refractive index layer has a refractive index of 1.60 or more,

the display unit has a display element and a light receiving sensor,

the 1 st phase difference layer and the linear polarization layer are laminated so as to cover the display element and the light receiving sensor.

2. The display device according to claim 1, wherein,

the 1 st retardation layer covers the entire surface of the linear polarization layer on the viewing side in plan view.

3. The display device according to claim 1 or 2, wherein,

the visibility-modifying monomer transmittance of the linear polarization layer is 42% or more.

4. The display device according to claim 1 or 2, wherein,

the angle formed by the slow axis of the 1 st phase difference layer and the absorption axis of the linear polarization layer is 10 DEG to 80 deg.

5. The display device according to claim 1 or 2, wherein,

the in-plane phase difference value at the wavelength 550nm of the 1 st phase difference layer is 80nm or more and 170nm or less.

6. The display device according to claim 5, wherein,

the 1 st phase difference layer has inverse wavelength dispersibility.

7. The display device according to claim 5, further comprising a 2 nd retardation layer between the high refractive index layer and the linearly polarizing layer,

the 2 nd phase difference layer is laminated so as to cover the display element and the light receiving sensor,

the thickness direction phase difference value of the 2 nd phase difference layer at the wavelength of 550nm is more than-140 nm and less than-20 nm.

8. The display device according to claim 1 or 2, wherein,

the stimulus value Y of the reflected light of the outgoing light from the display element when the high refractive index layer is reflected is 3.45% or more and 4.54% or less.

9. The display device according to claim 1 or 2, wherein,

the light receiving sensor can detect light with a wavelength of 320nm to 4000 nm.

10. The display device according to claim 1 or 2, wherein,

the outgoing light from the display element is light having a wavelength of 320nm to 4000 nm.

11. The display device according to claim 1 or 2, further comprising a 3 rd phase difference layer between the linearly polarizing layer and the display unit.

12. An optical laminate of a substrate and a substrate,

which comprises a high refractive index layer, a 1 st phase difference layer and a linear polarization layer in sequence,

The refractive index of the high refractive index layer is 1.60 or more.

13. The optical stack according to claim 12, wherein,

the 1 st retardation layer covers the entire surface of the linear polarization layer on the viewing side in plan view.

14. The optical stack according to claim 12 or 13, wherein,

the visibility-modifying monomer transmittance of the linear polarization layer is 42% or more.

15. The optical stack according to claim 12 or 13, wherein,

the angle formed by the slow axis of the 1 st phase difference layer and the absorption axis of the linear polarization layer is 10 DEG to 80 deg.

16. The optical stack according to claim 12 or 13, wherein,

the in-plane phase difference value at the wavelength 550nm of the 1 st phase difference layer is 80nm or more and 170nm or less.

17. The optical stack according to claim 12 or 13, wherein,

the 1 st phase difference layer has inverse wavelength dispersibility.

18. The optical laminate according to claim 12 or 13, further having a 2 nd phase difference layer between the high refractive index layer and the linear polarization layer,

the thickness direction phase difference value of the 2 nd phase difference layer at the wavelength of 550nm is more than-140 nm and less than-20 nm.

19. The optical stack according to claim 12 or 13, wherein,

the linear polarization layer further has a 3 rd retardation layer on the opposite side of the 1 st retardation layer side.