TW202323037A - Polarizing plate and optical display apparatus comprising the same - Google Patents

Abstract

Disclosed are a polarizing plate and an optical display apparatus including the same. The polarizing plate includes: a polarizer; and a first resin layer formed on at least one surface of the polarizer, wherein the first resin layer includes at least one selected from among wires and fibers, and at least some of the at least one selected from among the wires and the fibers are aligned at an orientation angle (θ) of 65° to 115° or at an orientation angle (θ) of 0° to 25° with respect to a light absorption axis of the polarizer.

Description

Polarizing plate and optical display device including same

[ Cross References to Related Applications ]

This application claims the benefit of Korean Patent Application No. 10-2021-0115616 filed with the Korea Intellectual Property Office on Aug. 31, 2021, the entire disclosure of which is incorporated herein by reference.

The invention relates to a polarizing plate and an optical display device comprising the polarizing plate.

The liquid crystal display is operated by passing light emitted from the backlight unit through the light source side polarizing plate, the liquid crystal panel, and the viewer side polarizing plate in the stated order. Light emitted from the light source is diffused through the backlight unit before entering the light source side polarizing plate. Therefore, when the diffused light passes through the light source side polarizing plate, the liquid crystal panel, and the viewer side polarizing plate, there is a problem of gradual deterioration of contrast ratio and visibility from the front side to the lateral side.

In order to improve the contrast ratio or visibility at the front and lateral sides, it has been considered to add a contrast or visibility enhancing layer to the viewer's side polarizing plate. The contrast or visibility enhancing layer has an embossed or engraved optical pattern at the interface between the low index layer and the high index layer such that light can be refracted by the optical pattern, thereby improving contrast ratio and visibility.

However, having a contrast or visibility enhancing layer such as an optical pattern necessarily requires a patterning process. Furthermore, a contrast or visibility enhancing layer requires two layers, namely a low index layer and a high index layer. The pattern forming process is realized by a hard molding process and a soft molding process, in which patterns are engraved on a patterned roll at a certain pitch to be transferred from the patterned roll to the film. However, if defects are formed on the pattern roller during the pattern forming process, the defects are also transferred to the film to which the pattern is to be transferred, thereby causing deterioration of processability. Therefore, the contrast or visibility enhancing layer may make it difficult to manufacture the polarizing plate and may require additional cost while increasing the thickness of the polarizing plate.

The background art of the present invention is disclosed in Korean Patent Laid-Open Publication No. 10-2018-0047569 and similar publications.

An object of the present invention is to provide a polarizing plate having improved contrast ratio and/or visibility without an optical pattern or a pattern layer including an optical pattern.

Another object of the present invention is to provide a polarizing plate which improves manufacturing processability and achieves thickness reduction by being prepared without an optical pattern or pattern layer.

Still another object of the present invention is to provide a polarizing plate with improved contrast ratio and/or visibility without white haze.

Still another object of the present invention is to provide a polarizing plate having improved brightness, contrast ratio, and viewing angle compared to a polarizing plate including an optical pattern or a pattern layer including an optical pattern.

One aspect of the present invention relates to a polarizing plate.

1. The polarizer comprises: a polarizer; and a first resin layer formed on at least one surface of the polarizer, wherein the first resin layer includes at least one selected from wires and fibers, and is selected from wires and fibers At least some of at least one of them are aligned at an orientation angle (θ) of 65° to 115° or at an orientation angle (θ) of 0° to 25° with respect to a light absorption axis of the polarizer.

2. In 1, the first resin layer is a contrast ratio and/or visibility enhancing layer.

3. In 1 and 2, 60% by weight or more of the total amount of wires and fibers in the first resin layer is aligned at an orientation angle (θ) with respect to the light absorption axis of the polarizer.

4. In 1 to 3, 80% by weight or more of the wires and fibers are independently dispersed in the first resin layer.

5. In 1 to 4, the first resin layer is separated from the polarizer by a distance (ΔD) of 0 μm to 200 μm.

6. In 1 to 5, the first resin layer has a refractive index of 1.40 to 1.80.

7. In 1 to 6, the wire or fiber has an aspect ratio of 500 or less.

8. In 1 to 7, at least one selected from wires and fibers is present in the first resin layer in an amount of 1% by weight to 40% by weight.

9. In 1 to 8, the first resin layer further includes a matrix in which at least one selected from wires and fibers is embedded, and at least one selected from wires and fibers has a higher density than the matrix. High refractive index.

10. In 1 to 9, the first resin layer has a haze of 40% or less.

11. In 1 to 10, at least one selected from the wire and the fiber is formed from at least one selected from the following: metal, non-metal, metal oxide, non-metal oxide, metal sulfide, non-metal Metal sulfides, metal nitrides, non-metal nitrides, metal hydroxides, non-metal hydroxides, and glasses.

12. In 1 to 11, at least one selected from wires and fibers is formed of zinc oxide.

13. In 1 to 12, the polarizer includes: a polarizer; and a first resin layer and a first protective layer, which are sequentially stacked on the light emitting surface of the polarizer.

14. In 1 to 13, the light exit surface of the first resin layer is flat over the entire surface thereof.

15. In 1 to 14, the first resin layer directly contacts the first protective layer, and the laminate of the first resin layer and the first protective layer has a haze of 60% or less.

16. In 1 to 15, the polarizing plate further includes a second resin layer stacked on one surface of the first resin layer or stacked on the other surface of the first resin layer.

17. In 16, the patterned portion is formed at an interface between the first resin layer and the second resin layer.

18. In 1 to 17, the patterned portion comprises an embossed optical pattern and a separation surface directly adjacent to the embossed optical pattern.

19. In 1 to 18, the sloped surface of the embossed optical pattern comprises a single flat, curved or angled flat surface.

20. In 1 to 19, the second resin layer has a higher refractive index than the first resin layer.

21. In 1 to 20, the laminate of the first resin layer, the second resin layer, and the first protective layer has a haze of 60% or less.

Another aspect of the present invention relates to an optical display device.

An optical display device includes the polarizing plate according to the present invention.

The present invention provides a polarizing plate that improves contrast ratio and/or visibility without an optical pattern or a pattern layer including an optical pattern.

The present invention provides a polarizing plate that improves manufacturing processability and achieves thickness reduction by preparing without an optical pattern or pattern layer.

The present invention provides a polarizing plate that further improves contrast ratio and/or visibility while minimizing white turbidity.

The present invention provides a polarizing plate having improved brightness, contrast ratio, and viewing angle compared to a polarizing plate including an optical pattern or a pattern layer including an optical pattern.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention. It should be understood that the present invention can be embodied in various ways and is not limited to the following examples.

In the drawings, components irrelevant to the description are omitted for clear description of the present invention, and the same components will be denoted by the same reference numerals throughout the specification.

Herein, spatially relative terms such as "upper" and "lower" are defined with reference to the accompanying drawings. Thus, it will be understood that "upper surface" may be used interchangeably with "lower surface" and that when an element such as a layer or film is referred to as being placed "on another element", it may be placed directly on another element, Or there may be intervening elements. On the other hand, when an element is referred to as being "directly on" another element, there are no intervening elements present.

Herein, the terms "horizontal direction" and "vertical direction" mean the longitudinal direction and the lateral direction of the rectangular screen of the liquid crystal display, respectively. Assuming that the front side is indicated by 0°, the left endpoint is indicated by -90°, and the right endpoint is indicated by 90° with reference to the horizontal, "lateral" side means -60° or 60°.

Herein, "refractive index" means a value measured using a refractometer at a wavelength of 550 nm.

Herein, "haze" and "light transmittance" mean values measured in the visible spectrum, for example in the wavelength range of 380 nm to 800 nm, specifically the amount at a wavelength of 550 nm measured value.

Herein, "top portion" refers to the highest point of the embossed optical pattern.

As used herein, the "aspect ratio" of an embossed optical pattern refers to the ratio of the maximum height of the embossed optical pattern to its maximum width (maximum height/maximum width).

Herein, "bottom angle" means the angle defined between the maximum width of the optical pattern and the inclined surface of the optical pattern directly connected to the maximum width of the optical pattern.

Herein, "in-plane retardation (Re)" is a value measured at a wavelength of 550 nm, and is expressed by formula A: Re = (nx-ny)×d, ---(A) Where nx and ny are the refractive indices of the protective layer in the direction of the slow axis and the direction of the fast axis respectively at a wavelength of 550 nm, and d is the thickness of the protective layer (unit: nanometer).

As used herein, the term "(meth)acrylic" refers to acrylic and/or methacrylic.

As used herein to indicate a specific numerical range, "X to Y" means "X≤and≤Y".

The inventors of the present invention have developed a polarizing plate that improves contrast ratio and/or visibility without an optical pattern or a pattern layer including an optical pattern. Since the polarizing plate according to the present invention does not include an optical pattern or a pattern layer, the polarizing plate according to the present invention can improve manufacturing processability while achieving thickness reduction. The polarizing plate according to the present invention further improves contrast ratio and/or visibility by minimizing white turbidity. The present invention provides a polarizing plate having improved contrast ratio and/or visibility compared to a polarizing plate including an optical pattern or a pattern layer including an optical pattern.

The polarizer according to the present invention includes: a polarizer; and a first resin layer formed on at least one surface of the polarizer, wherein the first resin layer includes at least one selected from wires and fibers, and is selected from wires and At least some of at least one of the fibers are aligned at an orientation angle (θ) of 65° to 115° or 0° to 25° with respect to the light absorption axis of the polarizer.

Each of the wires and fibers can have an aspect ratio (length-to-diameter ratio) of 5 to 500, which provides a shape with a length much greater than its diameter, thereby helping to improve contrast ratio and visibility. In particular, each of the wires and fibers may have an aspect ratio of 5, greater than 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80 ,85,90,95,100,105,110,115,120,125,130,135,140,145,150,155,160,165,170,175,180,185,190,195,200,205 ,210,215,220,225,230,235,240,245,250,255,260,265,270,275,280,285,290,295,300,305,310,315,320,325,330 ,335,340,345,350,355,360,365,370,375,380,385,390,395,400,405,410,415,420,425,430,435,440,445,450,455 , 460, 465, 470, 475, 480, 485, 490, 495 or 500.

The diameter of the wire can be 20 microns or less, preferably greater than 0 microns and less than 10 microns, and the diameter of the fibers can be 20 microns or less, preferably 10 microns or greater.

Hereinafter, a polarizing plate according to one embodiment of the present invention will be described with reference to FIG. 1 .

1, the polarizer may include: a polarizer 100; a first resin layer 200, a first protective layer 300 stacked on one surface of the polarizer 100; and a second protective layer 400 stacked on the other side of the polarizer 100. On the surface.

When the polarizer is applied to an optical display device, one surface of the polarizer 100 may be a light exit surface of the polarizer with respect to internal light of the optical display device. Accordingly, the first resin layer 200 may be stacked on the light exit surface of the polarizer with respect to internal light. However, it should be understood that the present invention is not limited thereto. Alternatively, the first resin layer 200 may be stacked on the light incident surface of the polarizer 100 with respect to internal light of the optical display device. Preferably, the first resin layer 200 is stacked on the light emitting surface of the polarizer relative to the internal light. Herein, "internal light" means light emitted from a light source of a backlight unit and propagated through a polarizer. first resin layer 200

In the polarizing plate, the first resin layer 200 may serve as a contrast ratio and/or visibility enhancing layer.

As shown in FIG. 1 , each of the upper surface of the first resin layer 200 (ie, the light exit surface of the first resin layer 200 ) and its lower surface is a flat surface and is not patterned. However, the first resin layer 200 includes the wires 10 and/or fibers aligned at an orientation angle (θ) in the first resin layer 200 , thereby improving contrast ratio and/or visibility.

At least some of the wires and/or fibers are aligned at an orientation angle θ relative to the light absorption axis of the polarizer 100, wherein the orientation angle (θ) is between 65° and 115° or 0° to 25° relative to the light absorption axis of the polarizer within range. With this configuration, the polarizing plate improves the contrast ratio and visibility with respect to the light emitted from the polarizing plate at the front side and the lateral side.

Assuming that the light absorption axis of the polarizer is 0°, the orientation angle (θ) includes angles in a positive (+) direction corresponding to a clockwise direction and in a negative (−) direction corresponding to a counterclockwise direction. The orientation of wires and fibers can be monitored via light microscopy, but is not limited thereto. Specifically, the orientation angle (θ) can be 0°, 1°, 2°, 3°, 4°, 5°, 6°, 7°, 8°, 9°, 10°, 11°, 12°, 13°, 14°, 15°, 16°, 17°, 18°, 19°, 20°, 21°, 22°, 23°, 24°, 25°, 65°, 66°, 67°, 68° , 69°, 70°, 71°, 72°, 73°, 74°, 75°, 76°, 77°, 78°, 79°, 80°, 81°, 82°, 83°, 84°, 85 °, 86°, 87°, 88°, 89°, 90°, 91°, 92°, 93°, 94°, 95°, 96°, 97°, 98°, 99°, 100°, 101°, 102°, 103°, 104°, 105°, 106°, 107°, 108°, 109°, 110°, 111°, 112°, 113°, 114° or 115°, preferably between 0° and 20 ° or within the range of 70° to 90°.

Referring to FIG. 1 , the alignment direction of the wires will be described. When the wires are aligned via their configuration, the longitudinal direction of the wires defines its alignment direction. FIG. 1 illustrates a polarizer in which at least some of the wires are aligned substantially parallel to the light absorption axis of the polarizer.

In the first resin layer 200, 60% by weight or more of the total amount of wires and fibers, specifically 60% by weight, 61% by weight, 62% by weight, 63% by weight, 64% by weight, and 65% by weight , 66% by weight, 67% by weight, 68% by weight, 69% by weight, 70% by weight, 71% by weight, 72% by weight, 73% by weight, 74% by weight, 75% by weight, 76% by weight, 77% by weight, 78% by weight % by weight, 79% by weight, 80% by weight, 81% by weight, 82% by weight, 83% by weight, 84% by weight, 85% by weight, 86% by weight, 87% by weight, 88% by weight, 89% by weight, 90% by weight , 91% by weight, 92% by weight, 93% by weight, 94% by weight, 95% by weight, 96% by weight, 97% by weight, 98% by weight, 99% by weight or 100% by weight, preferably 85% by weight to 100% by weight % can be aligned at an orientation angle (θ) with respect to the light absorption axis of the polarizer 100 . Within this range, the polarizing plate can improve contrast ratio and visibility while reducing the amount of wires and fibers.

As described below, the wire or fiber has a shape in which the length of the wire or fiber is much larger than its diameter to allow internal light entering the first resin layer through the polarizer to be guided to the front side or the lateral side via contact with the wire or fiber, This helps to improve contrast ratio and/or visibility. This shape can improve contrast ratio and/or visibility at both the front and lateral sides. Conversely, light-diffusing particles having a rod shape (eg, an aspect ratio of less than 5) have a length much smaller than their diameter compared to wires, thereby resulting in no significant improvement in contrast ratio and/or visibility. Furthermore, light-diffusing particles having a spherical shape do not provide a significant improvement in contrast ratio and/or visibility.

The inventors of the present invention confirmed that, even in the absence of a typical pattern layer, by adjusting the orientation angle (θ) of the wires or fibers in the first resin layer, the polarizer can improve the emission from the polarizer relative to the front and lateral sides. The contrast ratio and visibility of the internal light.

Next, the structure of the first resin layer 200 including the wire 10 will be described. It should be understood, however, that the details of wire 10 may apply to fibers as well.

In the first resin layer 200, the wires 10 may be at least independently dispersed. Here, "independently dispersed" means that the wires are spaced apart from each other without forming a network via connections therebetween. When the wires are connected to each other, light is unevenly emitted from the first resin layer due to uneven contact between the connected portion of the wire and its disconnected portion upon contact with the wire, thereby improving the contrast ratio and visibility effect deteriorates. In one embodiment, the wires 10 do not form a network in the first resin layer 200 , so that the first resin layer 200 and the polarizer become non-conductive.

In one embodiment, 80% by weight or greater than 80% by weight of the wire, specifically 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87% by weight %, 88% by weight, 89% by weight, 90% by weight, 91% by weight, 92% by weight, 93% by weight, 94% by weight, 95% by weight, 96% by weight, 97% by weight, 98% by weight, 99% by weight or 100% by weight, preferably 90% to 100% by weight, of the wires can be independently dispersed in the first resin layer 200 . Within this range, the polarizing plate can improve contrast ratio and visibility while reducing the content of wires therein.

The first resin layer 200 may be separated from the polarizer 100 by a predetermined distance (ΔD). Accordingly, light entering the first resin layer through the polarizer is emitted from the first resin layer after being in contact with the wire, thereby improving contrast ratio and visibility.

Referring to FIG. 2, the distance (ΔD) between the first resin layer 200 and the polarizer 100 may be in the range of 0 microns to 200 microns, specifically 0 microns, 5 microns, 10 microns, 15 microns, 20 microns, 25 microns. Micron, 30 micron, 35 micron, 40 micron, 45 micron, 50 micron, 55 micron, 60 micron, 65 micron, 70 micron, 75 micron, 80 micron, 85 micron, 90 micron, 95 micron, 100 micron, 105 micron, 110 microns, 115 microns, 120 microns, 125 microns, 130 microns, 135 microns, 140 microns, 145 microns, 150 microns, 155 microns, 160 microns, 165 microns, 170 microns, 175 microns, 180 microns, 185 microns, 190 microns , 195 microns or 200 microns, preferably 1 micron to 90 microns. Within this range, the polarizing plate may improve contrast ratio and visibility through contact of the wire with light emitted from the polarizing plate.

In one embodiment, as shown in FIG. 1 , the first resin layer 200 may be an adhesive layer or a bonding layer. Therefore, when the first resin layer 200 directly contacts the polarizer 100 , the distance (ΔD) may be 0 microns. Within this range, the wire reacts with light emitted from the polarizer, thereby improving contrast ratio and visibility.

In another embodiment, the first resin layer 200 may be a non-adhesive layer or a non-joint layer. Therefore, when the bonding layer is further stacked between the polarizer 100 and the first resin layer 200 , the distance (ΔD) is greater than 0 μm and less than 200 μm, preferably 1 μm to 90 μm. Within this range, the wire reacts with light emitted from the polarizer, thereby improving contrast ratio and visibility.

In another embodiment, as shown in FIG. 3 , when the third protective layer 500 is further stacked between the first resin layer 200 and the polarizer 100 , the distance (ΔD) is greater than 0 μm and less than 200 μm, Preferably 20 microns to 90 microns. Within this range, the wire reacts with light emitted from the polarizer, thereby improving contrast ratio and visibility.

The first resin layer 200 may have a refractive index of 1.40 to 1.80, specifically 1.40, 1.45, 1.50, 1.55, 1.60, 1.65, 1.70, 1.75 or 1.80, preferably 1.40 to 1.79, more specifically 1.45 to 1.70 or 1.45 to 1.69. Within this range, the first resin layer 200 may have a suitable refractive index compared to the polarizer, thereby preventing influence on light transmittance of the polarizer even when the first resin layer 200 is adjacent to the polarizer.

The first resin layer 200 includes wires 10 and a matrix 20 embedded with wires 10 . The wires and the substrate have different refractive indices, thereby providing a great effect of improving the contrast ratio and visibility when the light emitted from the polarizer comes into contact with the metal wires.

In one embodiment, the difference in refractive index between the wire and the substrate may be 1.0 or less than 1.0, specifically 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 or 1.0, preferably is greater than 0 and less than 1.0, more preferably 0.1 to 0.7. Within this range, the first resin layer may assist in improving contrast ratio and visibility.

The wire 10 has a shape in which the length of the wire is much greater than its diameter, thereby helping to improve contrast ratio and visibility.

In one embodiment, the wires may include nanowires or microwires and may have an aspect ratio (aspect ratio) of 500 or less, specifically 200 or less, more specifically 5 to 200, or 10 to 100. Within this range, the first resin layer can assist in improving contrast ratio and visibility, and can be easily aligned.

The wires may include nanowires or microwires, and may have a diameter of 20 microns or less, specifically greater than 0 microns and less than 20 microns, more specifically 0.1 to 20 microns or 0.5 to 1 microns. The length of the wire can be 1 micron or greater, specifically 5 microns to 4,000 microns, more specifically 10 microns to 1000 microns. Within this range, the wire can easily achieve the above aspect ratio.

In the first resin layer 200, the wires 10 may be present in the following amount: 1% by weight to 40% by weight, specifically 1% by weight, 2% by weight, 3% by weight, 4% by weight, 5% by weight, 6% by weight , 7% by weight, 8% by weight, 9% by weight, 10% by weight, 11% by weight, 12% by weight, 13% by weight, 14% by weight, 15% by weight, 16% by weight, 17% by weight, 18% by weight, 19% by weight % by weight, 20% by weight, 21% by weight, 22% by weight, 23% by weight, 24% by weight, 25% by weight, 26% by weight, 27% by weight, 28% by weight, 29% by weight, 30% by weight, 31% by weight , 32% by weight, 33% by weight, 34% by weight, 35% by weight, 36% by weight, 37% by weight, 38% by weight, 39% by weight or 40% by weight, preferably 3% by weight to 15% by weight, more specifically For example, 4% by weight to 10% by weight. Within this range, the first resin layer may assist in improving contrast ratio and visibility while allowing easy adjustment of haze described below.

The wire 10 may have a higher or lower refractive index than the matrix 20 . Preferably, the wires have a higher index of refraction than the matrix, thereby helping to improve contrast ratio and visibility without white haze.

In one embodiment, the wire 10 may have a higher refractive index than the matrix, and the refractive index may be 1.5 or greater, specifically 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4 Or 2.5, preferably 1.5 to 2.3 or 1.52 to 2.3. Within this range, the polarizing plate can easily achieve the above-mentioned difference in refractive index.

In another embodiment, the wire 10 may have a lower refractive index than the matrix, and the refractive index may be 1.2 or greater than 1.2, specifically 1.2, 1.3, 1.4, 1.5 or 1.6, preferably 1.4 to 1.6, or 1.43 to 1.6. Within this range, the polarizing plate can easily achieve the above-mentioned difference in refractive index.

The wire 10 may include a wire formed from at least one selected from the group consisting of metals, metalloids, metal oxides, nonmetal oxides, metal sulfides, nonmetal sulfides, metal nitrides, metalloid nitrogen compounds, metal hydroxides, non-metal hydroxides, and glasses. Preferably, the first resin layer includes at least metal oxide wires in order to improve contrast ratio and visibility.

The metal may include at least one selected from the group consisting of silver, gold, zinc, platinum, nickel, copper, aluminum, tungsten, and calcium.

The non-metal may include at least one selected from the group consisting of silicon, indium, tin, germanium, and carbon.

The metal oxide may include at least one selected from zinc oxide, copper oxide, aluminum oxide, nickel oxide, tungsten oxide, and calcium oxide.

The metal sulfide may include at least one selected from the group consisting of silver sulfide, zinc sulfide, nickel sulfide, copper sulfide, aluminum sulfide, and tungsten sulfide.

The wire may include metal and at least one compound having two or more functional groups of chemical/physical bonds.

The matrix 20 contains the wires therein to allow the wires to achieve a consistent improvement in contrast ratio and visibility.

The matrix 20 may have a higher or lower refractive index than the wires.

In one embodiment, the matrix 20 may have a higher refractive index than the wires, and the refractive index may be 1.5 or greater, specifically 1.65 to 1.7. Within this range, the polarizing plate can easily achieve the above-mentioned difference in refractive index.

In another embodiment, the matrix 20 may have a lower refractive index than the wire, and the refractive index may be 1.2 or greater than 1.2, specifically 1.4 to 1.60, more specifically 1.43 to 1.59. Within this range, the polarizing plate can easily achieve the above-mentioned difference in refractive index.

The matrix 20 may be a bonding or adhesive layer exhibiting bonding or adhesive properties. In this case, the first resin layer may be directly stacked on the polarizer, thereby providing an effect of reducing the thickness of the polarizer. Preferably, the substrate can be a pressure sensitive adhesive (PSA). However, the substrate may be a non-bonding or non-adhesive layer that exhibits no bonding or adhesive properties.

The matrix 20 may be formed of a composition including a UV curable resin and/or a heat curable resin. For example, the matrix may comprise a composition comprising resins such as (meth)acrylic resins, urethane resins, epoxy resins, silicone resins, urethane (meth)acrylic resins, Ester resins and epoxy (meth)acrylate resins. The composition may further include photoinitiators, thermal initiators and various additives. In one embodiment, the substrate can be formed of pressure sensitive adhesive (PSA) to form an adhesive layer, and can be directly stacked on the polarizer.

In one embodiment, the matrix may be a composition for an adhesive layer comprising: a (meth)acrylic copolymer formed from a monomer mixture comprising alkyl-containing (meth)acrylic mono and hydroxyl-containing (meth)acrylic monomers; and curing agents. The first resin layer is formed by adding the wires to the composition for the adhesive layer and then depositing the composition, thereby assisting the alignment of the wires according to the present invention.

The light transmittance of the first resin layer 200 may be 80% or greater than 80%, specifically 80%, 85%, 90%, 95% or 100%, preferably 90% to 100%. The haze of the first resin layer 200 may be 40% or less than 40%, specifically 0%, 5%, 10%, 15%, 20%, 25%, 30%, 35% or 40%, preferably 0% to 35%, more particularly 10% to 30%. Within this range, the first resin layer may be applied to a polarizing plate and have a low level of white haze to assist in improving contrast ratio and visibility.

The thickness of the first resin layer 200 may be 50 microns or less than 50 microns, specifically greater than 0 microns, 5 microns, 10 microns, 15 microns, 20 microns, 25 microns, 30 microns, 35 microns, 40 microns, 45 microns or 50 microns, preferably greater than 0 microns and less than 25 microns, more specifically 5 microns to 20 microns. Within this range, the first resin layer may be applied to a polarizing plate.

Each of the upper surface (ie, the light exit surface including the wire layer) and its lower surface (ie, the light incident surface including the wire layer) of the first resin layer 200 may be a flat surface, as shown in FIG. 1 . draw. However, a predetermined pattern may be formed on the upper or lower surface of the first resin layer 200 . This structure will be described in detail with reference to FIGS. 4 , 6 , and 7 .

The lower surface of the first resin layer 200 may be a flat surface, as shown in FIG. 1 .

The first resin layer 200 can be formed from a composition by a typical method.

In one embodiment, the first resin layer 200 may be formed by depositing a composition for the first resin layer 200 (which is prepared by adding wires to the matrix composition) in a certain direction onto on the first protective layer 300 and then cured. Deposition and curing can be performed by typical methods well known to those skilled in the art.

The first resin layer 200 may be formed as a coating on the first protective layer 300 . In one embodiment, the first resin layer can be easily formed by depositing a composition for the first resin layer, followed by curing. First protective layer 300

The first protective layer 300 may be stacked on the light emitting surface of the first resin layer 200 to support the first resin layer 200 .

The light transmittance of the first protection layer 300 may be 80% or greater, such as 90% to 100%. Within this range, the first protective layer allows light to transmit therethrough without affecting incident light.

The first protective layer 300 may include a transparent substrate. The transparent substrate may have a different refractive index from the first resin layer 200 .

The transparent substrate may have a higher or lower refractive index than the first resin layer 200 . Preferably, the transparent substrate has a higher refractive index than the first resin layer 200 . In the case of transparent substrates, the first protective layer can help improve contrast ratio and visibility.

The transparent substrate may include an optically transparent resin film having a light incident surface and a light exit surface facing the light incident surface. The transparent substrate may be composed of a single resin film or a plurality of resin films. The resin may include at least a resin selected from cellulose ester resins such as triacetylcellulose (TAC) and the like; cyclic polyolefin resins such as amorphous cyclic olefin polymers (cyclic olefin polymer; COP) and the like; polycarbonate resins; polyester resins such as polyethylene terephthalate (PET) and the like; polyether resins; polyresins; polyamide resins; Polyimide resins; acyclic polyolefin resins; polypropylene resins, such as poly(methyl methacrylate) and the like; polyvinyl alcohol resins; polyvinyl chloride resins; and polyvinylidene chloride resins, but not limited to this. Preferably, the transparent substrate includes polyester resin including polyethylene terephthalate (PET) and the like, thereby further improving contrast ratio and visibility.

Although the transparent substrate may be an unstretched film, the transparent substrate may be an isotropic optical film or a retardation film prepared by stretching a resin using a predetermined method and having a certain range of retardation.

In one embodiment, the transparent substrate may be an isotropic optical film having a Re of 0 nm to 60 nm, specifically 40 nm to 60 nm. Within this range, the transparent substrate can provide good image quality through compensation of viewing angle. As used herein, "isotropic optical film" refers to a film in which nx, ny, and nz (nx, ny, and nz are the refractive indices in the slow axis direction, fast axis direction, and thickness direction at a wavelength of 550 nm, respectively) Films with substantially the same value. Here, the expression "substantially the same" not only includes the case where nx, ny, and nz have exactly the same value, but also includes the case where the values of nx, ny, and nz have little difference.

In another embodiment, the transparent substrate may be a retardation film having a Re of 60 nm or more. For example, Re of the transparent substrate may be 60 nm to 500 nm, or 60 nm to 300 nm. For example, the Re of the transparent substrate may be 6,000 nm or greater or 8,000 nm or greater, specifically 10,000 nm or greater, more specifically greater than 10,000 nm, and More particularly 10,100 nm to 30,000 nm or 10,100 nm to 15,000 nm. Within this range, the transparent substrate can prevent occurrence of color spots while further enhancing improvement in contrast ratio and visibility with respect to light diffused through the first resin layer.

The haze of the transparent substrate may be 30% or less, specifically 0.1% to 30%. Within this range, the transparent substrate may be applied to a polarizing plate.

The thickness of the transparent substrate may be 5 microns to 200 microns, for example, 10 microns to 90 microns. Within this range, the transparent substrate may be applied to a polarizing plate.

The first protective layer 300 may include a transparent substrate and a functional layer stacked on at least one surface of the transparent substrate. The functional layer may include at least one selected from the group consisting of a hard coat layer, a scattering layer, a low-refractive index layer, an ultra-low-refractive index layer, an undercoat layer, an anti-fingerprint layer, an anti-reflection layer, and an anti-glare layer.

The haze of the first protective layer 300 may be 30% or less, specifically 0.1% to 30% or 0.5% to 20%. Within this range, the first protective layer may be used in a polarizing plate, and may assist in improving contrast ratio and visibility by suppressing white turbidity.

The haze of the laminate of the first resin layer 200 and the first protective layer 300 may be 60% or less, specifically 0%, 0.1%, 0.5%, 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55% or 60%, preferably 0.1% to 55%, 0.1% to 45% or 10% to 40%. Within this range, the laminate may be applied to a polarizing plate and have white haze to assist in improving contrast ratio and visibility. Here, the haze can be achieved by adjusting the content of the wires in the first resin layer, the type of the functional layer in the first protective layer, and the haze of the transparent substrate.

Preferably, the laminate includes a first resin layer, a transparent substrate and at least one selected from the following: a low refractive index layer, an ultra-low refractive index layer, an anti-reflection layer and an anti-glare layer, preferably stacked Anti-reflection layer, low refractive index layer or ultra-low refractive index layer on the light exit surface of the transparent substrate. Here, the refractive index of the first protective layer 300 may be 5% or less, specifically, 0.1% to 3%. Within this range, the laminate can prevent the wires in the first resin layer from being observed. Polarizer 100

The polarizer 100 is used to polarize incident light from the liquid crystal panel and transmit the polarized light to the first resin layer 200 . The polarizer 100 may be stacked on the light incident surface of the first resin layer 200 in the polarizer. The light absorption axis of the polarizer 100 may correspond to its machine direction (MD).

The polarizer 100 may include a polyvinyl alcohol polarizer prepared by uniaxially stretching a polyvinyl alcohol film.

The polarizer 100 may have a thickness of 5 micrometers to 40 micrometers. Within this range, the polarizer can be used in optical display devices.

Although not shown in FIG. 1 , the first protective layer may be further stacked on the upper surface of the polarizer, that is, stacked on the light emitting surface of the polarizer. Second protective layer 400

The second protection layer 400 may be stacked on the light incident surface of the polarizer 100 in the polarizer.

The light transmittance of the second protective layer 400 may be 80% or greater, such as 90% to 100%. Within this range, the second protective layer allows incident light to be transmitted therethrough without affecting the incident light.

The second protective layer 400 may include a transparent substrate. The transparent substrate may include an optically transparent resin film having a light incident surface and a light exit surface facing the light incident surface. The transparent substrate may be composed of a single resin film or a plurality of resin films. The resin may include at least one resin selected from the following: cellulose ester resins such as triacetylcellulose (TAC) and the like; cyclic polyolefin resins such as amorphous cycloolefin polymer (cyclic Olefin polymer; COP) and the like; polycarbonate resins; polyester resins such as polyethylene terephthalate (PET) and the like; polyether resins; polyresins; polyamide resins ; polyimide resins; acyclic polyolefin resins; polypropylene resins, such as poly(methyl methacrylate) and the like; polyvinyl alcohol resins; polyvinyl chloride resins; and polyvinylidene chloride resins, provided that Not limited to this. Preferably, the transparent substrate includes polyester resin including polyethylene terephthalate (PET) and the like, thereby further improving contrast ratio and visibility.

Although the transparent substrate may be an unstretched film, the transparent substrate may be an isotropic optical film or a retardation film prepared by stretching a resin using a predetermined method and having a certain range of retardation.

In one embodiment, the transparent substrate can be an isotropic optical film having a Re of 0 nm to 60 nm, specifically 40 nm to 60 nm. Within this range, the transparent substrate can provide good image quality through compensation of viewing angle. As used herein, "isotropic optical film" refers to a film in which nx, ny, and nz (nx, ny, and nz are the refractive indices in the slow axis direction, fast axis direction, and thickness direction at a wavelength of 550 nm, respectively) Films with substantially the same value. Here, the expression "substantially the same" not only includes the case where nx, ny, and nz have exactly the same value, but also includes the case where the values of nx, ny, and nz have little difference.

In another embodiment, the transparent substrate may be a retardation film having a Re of 60 nm or more. For example, Re of the transparent substrate may be 60 nm to 500 nm, or 60 nm to 300 nm. For example, the Re of the transparent substrate may be 6,000 nm or greater or 8,000 nm or greater, specifically 10,000 nm or greater, more specifically greater than 10,000 nm, and More particularly 10,100 nm to 30,000 nm or 10,100 nm to 15,000 nm. Within this range, the transparent substrate can prevent occurrence of color spots while further enhancing improvement in contrast ratio and visibility with respect to light diffused through the first resin layer.

The thickness of the transparent substrate may be 5 microns to 200 microns, for example, 10 microns to 90 microns. Within this range, the transparent substrate may be applied to a polarizing plate.

Next, a polarizing plate according to another embodiment of the present invention will be described with reference to FIG. 3 .

3, the polarizer may include: a polarizer 100; a third protective layer 500, a first resin layer 200, and a first protective layer 300 stacked on one surface of the polarizer 100; and a second protective layer 400 stacked on on the other surface of the polarizer 100 . Except that the third protection layer 500 is further stacked between the polarizer 100 and the first resin layer 200 , the polarizer according to this embodiment is substantially the same as the polarizer shown in FIG. 1 . Therefore, the following description will focus on the third protective layer 500 .

The light transmittance of the third protection layer 500 may be 80% or greater, such as 90% to 100%. Within this range, the third protective layer allows light to transmit therethrough without affecting incident light.

The third protective layer 500 may include a transparent substrate. The transparent base of the third protective layer 500 may include a film formed of the same resin as that of the transparent base of the second protective layer 400 or a different resin. The transparent base of the third protective layer 500 may have the same Re or different Re from that of the transparent base of the second protective layer 400 .

Next, a polarizing plate according to still another embodiment of the present invention will be described with reference to FIG. 4 .

Referring to FIG. 4, the polarizer may include: a polarizer 100; a first resin layer 210 and a first protective layer 300 stacked on one surface of the polarizer 100; and a second protective layer 400 stacked on the other side of the polarizer 100. On the surface, one surface of the first resin layer 210 is patterned to have a specific pattern, and a space between the first resin layer 210 and the first protective layer 300 is filled with the second resin layer 600 .

Except one surface of the first resin layer 210 (that is, the light exit surface of the first resin layer 210 corresponding to the upper surface of the first resin layer (adjacent to the second resin layer 600 )) is patterned and the second resin layer 600 is further stacked between the first resin layer 210 and the first protective layer 300 , the polarizer according to this embodiment is substantially the same as the polarizer shown in FIG. 1 . Therefore, the following description will focus on the first resin layer 210 and the second resin layer 600 . first resin layer 210

In the polarizing plate, the first resin layer 210 may serve as a contrast ratio and/or visibility enhancing layer. The wire has a shape in which the length of the wire is much larger than its diameter to allow internal light emitted from the polarizer and entering the first resin layer to be directed to the front side or the lateral side through contact with the metal wire, thereby improving the contrast ratio and/or Visibility. This wire shape can improve contrast ratio and/or visibility at both the front and lateral sides. Conversely, light diffusing particles having a rod shape have a much smaller length than their diameter compared to wires, thereby providing an insignificant improvement in contrast ratio and/or visibility. Additionally, light-diffusing particles having a spherical shape may provide insignificant improvements in contrast ratio and/or visibility.

The wires are aligned at an orientation angle (θ) in the first resin layer 210 .

Specifically, at least some of the wires are aligned at an orientation angle (θ) of 65° to 115° or 0° to 25° with respect to the light absorption axis of the polarizer 100, thereby improving self-polarization with respect to the front and lateral sides. The contrast ratio and visibility of the light emitted by the sheet. Specifically, the orientation angle (θ) is in the range of 65° to 115° or 0° to 25° with respect to the light absorption axis of the polarizer. Specifically, the orientation angle (θ) can be 0°, 1°, 2°, 3°, 4°, 5°, 6°, 7°, 8°, 9°, 10°, 11°, 12°, 13°, 14°, 15°, 16°, 17°, 18°, 19°, 20°, 21°, 22°, 23°, 24°, 25°, 65°, 66°, 67°, 68° , 69°, 70°, 71°, 72°, 73°, 74°, 75°, 76°, 77°, 78°, 79°, 80°, 81°, 82°, 83°, 84°, 85 °, 86°, 87°, 88°, 89°, 90°, 91°, 92°, 93°, 94°, 95°, 96°, 97°, 98°, 99°, 100°, 101°, 102°, 103°, 104°, 105°, 106°, 107°, 108°, 109°, 110°, 111°, 112°, 113°, 114° or 115°, preferably between 0° and 20 ° or within the range of 70° to 90°.

In one embodiment, in the first resin layer 210, 60% by weight or more, specifically, 85% to 100% by weight of wire. Within this range, the polarizing plate can improve contrast ratio and visibility while reducing the amount of wires. FIG. 4 illustrates a polarizer with at least some wires arranged substantially perpendicular to the light absorption axis of the polarizer.

In the first resin layer 210, the wires may be at least independently dispersed. Here, the expression "independently dispersed" has the same meaning as in FIG. 1 . In one embodiment, 80% by weight or more than 80% by weight, specifically 90% to 100% by weight of the wires may be independently dispersed in the first resin layer 210 . Within this range, the polarizing plate can improve contrast ratio and visibility while reducing the amount of wires. In one embodiment, the first resin layer 210 , the laminate of the first resin layer 210 and the second resin layer 600 , and the polarizer may be non-conductive.

The first resin layer 210 may be separated from the polarizer 100 by a predetermined distance (ΔD). Accordingly, light entering the first resin layer through the polarizer is emitted from the first resin layer after being in contact with the wire, thereby improving contrast ratio and visibility.

Referring to FIG. 5 , the distance (ΔD) between the first resin layer 210 and the polarizer 100 (for example, the distance between the lower surface of the first resin layer 210 and the polarizer 100 ) may be in the following range: 0 μm to 200 μm, Specifically 0 microns, 5 microns, 10 microns, 15 microns, 20 microns, 25 microns, 30 microns, 35 microns, 40 microns, 45 microns, 50 microns, 55 microns, 60 microns, 65 microns, 70 microns, 75 microns , 80 microns, 85 microns, 90 microns, 95 microns, 100 microns, 105 microns, 110 microns, 115 microns, 120 microns, 125 microns, 130 microns, 135 microns, 140 microns, 145 microns, 150 microns, 155 microns, 160 micron, 165 micron, 170 micron, 175 micron, 180 micron, 185 micron, 190 micron, 195 micron or 200 micron, preferably 1 micron to 90 micron. Within this range, the polarizing plate may improve contrast ratio and visibility through contact of light emitted from the polarizing plate with the wire.

The refractive index of the first resin layer 210 may be 1.40 to 1.80, specifically 1.40, 1.45, 1.50, 1.55, 1.60, 1.65, 1.70, 1.75, 1.80, 1.40 to 1.79, 1.45 to 1.70, or 1.45 to 1.69. Within this range, the first resin layer 210 may have a suitable refractive index compared to the polarizer, thereby preventing influence on light transmittance of the polarizer even when the first resin layer 210 is adjacent to the polarizer.

The first resin layer 210 includes the wire 10 and the matrix 20 embedded with the wire 10 . The wires and the substrate have different refractive indices, thereby providing a great effect of improving the contrast ratio and visibility when the light emitted from the polarizer comes into contact with the metal wires. In one embodiment, the difference in refractive index between the wire and the matrix may be 1.0 or less, specifically 0.1 to 0.7. Within this range, the first resin layer may assist in improving contrast ratio and visibility.

The wires may have aspect ratios, diameters and lengths as described with reference to FIG. 1 . In the first resin layer 200, the wires may be present in the following amounts: 1% by weight to 40% by weight, specifically 1% by weight, 2% by weight, 3% by weight, 4% by weight, 5% by weight, 6% by weight, 7% by weight, 8% by weight, 9% by weight, 10% by weight, 11% by weight, 12% by weight, 13% by weight, 14% by weight, 15% by weight, 16% by weight, 17% by weight, 18% by weight, 19% by weight %, 20% by weight, 21% by weight, 22% by weight, 23% by weight, 24% by weight, 25% by weight, 26% by weight, 27% by weight, 28% by weight, 29% by weight, 30% by weight, 31% by weight, 32 wt%, 33 wt%, 34 wt%, 35 wt%, 36 wt%, 37 wt%, 38 wt%, 39 wt% or 40 wt%, preferably 3 wt% to 15 wt%. Within this range, the first resin layer may assist in improving contrast ratio and visibility while allowing easy adjustment of haze described below.

The wires may have a higher or lower refractive index than the matrix. Preferably, the wires have a higher index of refraction than the matrix, thereby helping to improve contrast ratio and visibility while minimizing white haze.

In one embodiment, the wire may have a higher refractive index than the matrix, and the refractive index may be 1.5 or greater, specifically 1.52 to 2.3. Within this range, the polarizing plate can easily achieve the above-mentioned difference in refractive index. In another embodiment, the wire may have a lower refractive index than the matrix, and the refractive index may be 1.2 or greater, specifically 1.43 to 1.6. Within this range, the polarizing plate can easily achieve the above-mentioned difference in refractive index.

The wires may include at least one type of wire described in FIG. 1 .

The matrix can have the refractive index described in FIG. 1 and can be formed from the materials described in FIG. 1 .

The upper surface of the first resin layer 210 is patterned to form a patterned portion.

The patterned part can facilitate the improvement of contrast ratio and visibility by wire.

Referring to FIG. 6 , the patterned portion may be formed through repeated combinations of an embossed optical pattern 211 and a separation surface 212 adjacent to the embossed optical pattern 211 . The second resin layer 600 has a different refractive index from that of the first resin layer 210, and the embossed optical pattern 211 allows the light emitted through contact with the wire to go toward the second resin layer through refraction at a specific pattern, thereby further improving the reflection on the second resin layer. ratio and visibility.

The embossed optical pattern 211 may protrude from the first resin layer 210 to the second resin layer 600 . The embossed optical pattern 211 includes an inclined surface 213 formed directly on the separation surface 212 . The sloped surface 213 may consist of a single flat, curved or angled flat surface. Accordingly, light emitted from the first resin layer and entering the second resin layer is refracted by the patterned portion, thereby improving the contrast ratio and visibility at the front and lateral sides.

Assuming that the angle defined between the inclined surface 213 and the maximum width W1 of the embossed optical pattern 211 is a base angle θ1, the base angle θ1 of the embossed optical pattern 211 may be 60° to 90°, specifically 75° or more and less than 90°, more particularly 75° to 85°. Within this range, the embossed optical pattern 211 can assist in improving contrast ratio and visibility.

(A) of FIG. 6 shows an embossed optical pattern having a trapezoidal shape, wherein the inclined surface is composed of a single flat surface. However, the embossed optical pattern may have not only a triangular cross section but also an N-shaped cross section (N is an integer of 4 to 10) including a trapezoidal, rectangular or square cross section having a flat surface at its top portion.

The aspect ratio (height to maximum width ratio, H/W1) of the embossed optical pattern 211 may be 3 or less, specifically 0.1, 0.5, 1, 1.5, 2, 2.5 or 3, preferably 0.3 to 3, 0.4 to 2, more particularly 0.6 to 1.3. Within this range, the embossed optical pattern can assist in improving contrast ratio and visibility.

The embossed optical pattern 211 may satisfy Relational Expression 1. By satisfying the relation 1, the embossed optical pattern 211 can help to improve the lateral contrast ratio, while improving the contrast ratio at the same lateral viewing angle. Preferably, the embossed optical pattern 211 has a P1/W1 of 1.2-8. [relational expression 1] 1 < P1/W1 ≤ 10 Where P1 is the pitch of the patterned part (unit: micron) and W1 is the maximum width of the embossed optical pattern (unit: micron).

The height (H) of the embossed optical pattern 211 may be 40 microns or less, specifically 30 microns or less, more specifically 3 microns to 25 microns. Within this range, the embossed optical pattern can assist in improving contrast ratio, viewing angle, and brightness. The embossed optical pattern may have a maximum width (W1) of 50 microns or less, specifically 30 microns or less, more specifically 3 microns to 15 microns, or 15 microns to 25 microns. Within this range, the embossed optical pattern can assist in improving contrast ratio, viewing angle, and brightness without moiré phenomenon. The pitch (W1+L) of the embossed optical pattern 211 may be 50 microns or less, specifically 30 microns or less, more specifically 3 microns to 15 microns, or 15 microns to 25 microns. Within this range, the embossed optical pattern can improve contrast ratio, viewing angle, and brightness without moire phenomenon.

The embossed optical pattern 211 may include a first facet 214 at a top portion thereof. The first facet 214 can be a flat surface, an angled flat surface, or a curved surface. The maximum width W2 of the first facet 214 may be 50 microns or less, specifically 30 microns or less, more specifically 3 microns to 15 microns, or 15 microns to 25 microns. Within this range, the embossed optical pattern 211 can assist in improving contrast ratio and visibility.

In the embossed optical pattern 211, the wires may be dispersed. The wires may be aligned at an orientation angle (θ) of 65° to 115° or an orientation angle (θ) of 0° to 25° with respect to the light absorption axis of the polarizer 100 . Within this range, the embossed optical pattern 211 may improve contrast ratio and visibility with respect to light emitted from the polarizer at the front and lateral sides. The embossed optical pattern can include the wires and substrates described above. Preferably, the orientation angle (θ) is in the range of 0° to 20° or in the range of 70° to 90°.

The separation surface 212 can improve the contrast ratio and visibility at the front side by allowing incident light received vertically from the first resin layer to be emitted therethrough. The maximum width (L) of the separating surface 212 may be 50 microns or less, specifically 30 microns or less, more specifically 2 microns to 15 microns, or 15 microns to 25 microns. Within this range, the effects of the present invention can be easily achieved.

The first resin layer 210 may contain wires in its region excluding the embossed optical pattern 211, that is, in the region between the lower surface of the first resin layer 210 and the separation surface and in the region of the largest width of the optical pattern. wire. The wires can be aligned at an orientation angle (θ) relative to the light absorption axis of the polarizer, thereby improving the contrast ratio and visibility relative to light emitted from the polarizer at the front and lateral sides.

Although not shown in FIG. 4 , the embossed optical pattern 211 may have a strip shape extending in its longitudinal direction. With this structure, the embossed optical pattern can improve viewing angles at right and left sides. Here, the longitudinal direction of the embossed optical pattern means a direction different from the maximum width direction of the embossed optical pattern, for example, a direction orthogonal thereto. FIG. 4 shows a structure in which the light absorption axis of the polarizer is substantially perpendicular to the longitudinal direction of the embossed optical pattern.

In one embodiment, assuming that the light absorption axis of the polarizer is 0°, it is defined as the angle between the longitudinal direction of the embossed optical pattern and the light absorption axis of the polarizer 100 (that is, the orientation angle (θ)), May be in the range of 0° to 20° or in the range of 70° to 90°, in particular 0°, 1°, 2°, 3°, 4°, 5°, 6°, 7°, 8° , 9°, 10°, 11°, 12°, 13°, 14°, 15°, 16°, 17°, 18°, 19°, 20°, 70°, 71°, 72°, 73°, 74 °, 75°, 76°, 77°, 78°, 79°, 80°, 81°, 82°, 83°, 84°, 85°, 86°, 87°, 88°, 89°, or 90°. Within this range, the polarizing plate can prevent the pixel moiré phenomenon of the liquid crystal panel.

Referring to (B) and (C) of FIG. 6 , when the inclined surface is an angled flat surface, the inclined surface may protrude from the first resin layer 210 to the second resin layer 600 . Alternatively, the inclined surface may protrude from the second resin layer 600 to the first resin layer 210 .

Referring to (D) and (E) of FIG. 6, when the inclined surface is a curved surface, the embossed optical pattern may include a curved surface protruding from the first resin layer 210 to the second resin layer 600 (see (D) of FIG. )) or protrude from the second resin layer 600 to the curved surface of the first resin layer 210 ((E) of FIG. 6 ).

The second resin layer 600 may fill at least part of a space between the embossed optical pattern 211 and the first protective layer 300 . In one embodiment, the lower surface of the second resin layer 600 may be partially patterned by patterning.

The second resin layer 600 may include wires or may not include wires. Preferably, the second resin layer 600 does not contain wires to prevent wires from being observed due to use of excess wires.

The second resin layer 600 may have a different refractive index from the first resin layer 210 . The second resin layer 600 may have a higher or lower refractive index than the first resin layer 210 . Preferably, the second resin layer 600 has a higher refractive index than the first resin layer 210, thereby further improving the contrast ratio and visibility.

The difference in refractive index between the second resin layer 600 and the first resin layer 210 may be 0.05 to 0.2, specifically 0.1 to 0.16. Within this range, the polarizing plate can further improve contrast ratio and visibility.

In one embodiment, the refractive index of the second resin layer 600 may be 1.4 or greater than 1.4, specifically 1.5 to 1.7, more specifically 1.58 to 1.66. Within this range, the above-mentioned refractive index difference can be easily achieved.

The second resin layer 600 may be formed of a composition including UV curable resin and/or heat curable resin. For example, the second resin layer 600 may be made of resins such as (meth)acrylic resins, urethane resins, epoxy resins, silicone resins, urethane (meth)acrylate resins, and rings. Oxygen (meth)acrylate resin) composition. The composition may further include photoinitiators, thermal initiators and various additives.

The haze of the laminated body of the first resin layer 210, the second resin layer, and the first protective layer 300 may be 60% or less, specifically 0%, 1%, 5%, 10%, 15%, 20%. %, 25%, 30%, 35%, 40%, 45%, 50%, 55% or 60%, preferably 1% to 50%, or 30% to 50%. Within this range, the laminate can be applied to a polarizing plate and has a low degree of white haze to assist in improving contrast ratio and visibility.

Preferably, the laminate includes a first resin layer, a second resin layer, a transparent substrate, and at least one selected from the group consisting of a low refractive index layer, an ultra-low refractive index layer, an anti-reflection layer, and an anti-glare layer , preferably a low-refractive-index layer or an ultra-low-refractive-index layer stacked on the light-exiting surface of the transparent substrate. Here, the refractive index of the first protective layer 300 may be 5% or less, specifically, 0.1% to 3%. Within this range, the laminate can prevent the wires in the first resin layer from being observed.

The maximum thickness of the second resin layer 600 may be greater than 0 micrometers and less than 50 micrometers, for example, greater than 0 micrometers and less than 30 micrometers. Within this range, it is possible to prevent the polarizing plate from being subjected to bending, such as warping.

The distance between the upper surface of the second resin layer 600 and the upper surface of the embossed optical pattern 211 (that is, the maximum thickness of the second resin layer 600−the maximum height of the embossed optical pattern 211) (also referred to as “wall thickness ”) may have a value from 0 microns to 30 microns, for example greater than 0 microns and less than 20 microns, or greater than 0 microns and less than 10 microns. Within this range, the second resin layer can achieve increased surface hardness and sufficient adhesion to the protective film.

Next, a polarizing plate according to still another embodiment of the present invention will be described with reference to FIG. 7 .

Referring to FIG. 7, the polarizer may include: a polarizer 100; a first resin layer 210 and a first protective layer 300 stacked on one surface of the polarizer 100; and a second protective layer 400 stacked on the other side of the polarizer 100. On the surface, one surface of the first resin layer 210 is patterned to have a specific pattern, and a space between the first resin layer 210 and the polarizer 100 is filled with the second resin layer 600 .

The other surface except the first resin layer 210 (that is, the light incident surface of the first resin layer 210 corresponding to the lower surface of the first resin layer (adjacent to the second resin layer 600 )) is patterned and the second resin Except that the layer 600 is further stacked between the first resin layer 210 and the polarizer 100 , the polarizer according to this embodiment is substantially the same as the polarizer of FIG. 4 .

Although not shown in the figure, the polarizer shown in FIG. 7 may have an embossed optical pattern as shown in FIG. 6 .

An optical display device according to the present invention includes the polarizing plate according to the present invention.

In one embodiment, an optical display device according to the present invention may include the polarizing plate according to the present invention as a viewer-side polarizing plate with respect to a liquid crystal panel. Here, the viewer-side polarizing plate refers to a polarizing plate disposed facing the screen (ie, facing the light source of the optical display device) with respect to the liquid crystal panel.

In one embodiment, a liquid crystal display may include a light-collecting backlight unit, a light source-side polarizer, a liquid crystal panel, and a viewer-side polarizer stacked sequentially in the stated order, wherein the viewer-side polarizer includes the polarizer according to the present invention . Herein, the light source side polarizing plate is the polarizing plate at the light source side. The liquid crystal panel can adopt vertical alignment (vertical alignment; VA) mode, IPS mode, patterned vertical alignment (patterned vertical alignment; PVA) mode or super-patterned vertical alignment (super-patterned vertical alignment; S-PVA) mode, but not limited to this.

Next, the present invention will be described in more detail with reference to some examples. It should be noted, however, that these examples are provided for illustration only and should not be construed as limiting the invention in any way. Example 1

(1) Preparation of a polyethylene terephthalate (PET) film (DSG-23, haze: 0.6%) having an antireflection layer on its upper surface, Dai Nippon Printing Co., Ltd. .)).

A composition for the first resin layer was prepared by mixing a zinc oxide-containing wire composition (aspect ratio of the zinc oxide wire: 90, diameter of the zinc oxide wire: 0.7 μm) and an acrylic pressure-sensitive adhesive composition.

A composition including a matrix (refractive index: 1.47) and a zinc oxide wire (refractive index: 1.47) and zinc oxide wires (refractive index: 2.0) for the first resin layer (refractive index: 1.48). Thus, a laminate of antireflection layer/PET film/first resin layer was prepared and had a haze of 17%.

(2) A polarizer (thickness: 13 µm, light transmittance: 44%) was prepared by stretching a polyvinyl alcohol film to 3 times its original length at 60°C and dyeing the stretched polyethylene with iodine Alcohol film, followed by stretching of the dyed polyvinyl alcohol film to 2.5 times in boric acid aqueous solution at 40 °C.

A polyethylene terephthalate (PET) film (TA-053, Toyobo Co., Ltd.) was bonded to the upper surface of the polarizer, followed by a cyclic olefin polymer (COP) A film (ZEON company) was bonded to the lower surface of the polarizer, whereby a laminate of PET film/polarizer/COP film was prepared.

(3) The PET film of the laminate is bonded to the first resin layer containing the zinc oxide wire, whereby the antireflection layer, PET film, first resin layer, PET film, polarizer, and COP film are prepared in the stated order Stacked polarizers. The orientation angle (θ) is 0°. Example 2

A polarizing plate was prepared in the same manner as in Example 1 except that the orientation angle (θ) was changed to 90°. Example 3

A polarizing plate was prepared in the same manner as in Example 1 except that the laminate of the antireflection layer/PET film/first resin layer was formed to have a haze of 32% by changing the content of the zinc oxide wire. Example 4

A polarizing plate was prepared in the same manner as in Example 1 except that the orientation angle (θ) was changed to 20°. Example 5

A polarizing plate was prepared in the same manner as in Example 1 except that the orientation angle (θ) was changed to 70°. Example 6

(1) Preparation of a polyethylene terephthalate (PET) film (DSG-23, haze: 0.6%) having an antireflection layer on its upper surface, Dai Nippon Printing Co., Ltd. .)). The second resin layer (refractive index: 1.59) was formed by applying a composition for the second resin layer to a predetermined thickness on the lower surface of the PET film, followed by patterning and drying the composition.

A composition for the first resin layer was prepared by mixing a zinc oxide-containing wire composition (aspect ratio of the zinc oxide wire: 90, diameter of the zinc oxide wire: 0.7 μm) and an acrylic pressure-sensitive adhesive composition. Formed on the lower surface of the PET film by depositing the composition for the first resin layer on the lower surface of the PET film in one direction, followed by drying the composition including a matrix (refractive index: 1.47) and zinc oxide wires (refractive index: 2.0) of the first resin layer (refractive index: 1.48).

Thus, a laminate of antireflection layer/PET film/second resin layer/first resin layer was prepared and had a haze of 41%.

Table 1 shows the sections of the patterned part. Table 1 h W1 W2 L θ1 10.4 μm 10.2 μm 9.3 μm 9.8 μm 85°

(2) A laminate of PET film/polarizer/COP film was prepared in the same manner as in Example 1.

(3) The first resin layer of the laminate is bonded to the PET film of the laminate, whereby the antireflection layer, PET film, second resin layer, first resin layer, PET film, polarizer, and COP film are prepared as stated Polarizers stacked sequentially. The orientation angle (θ) is 0°. Example 7

A polarizing plate was prepared in the same manner as in Example 6, except that the laminate of the antireflection layer/PET film/second resin layer/first resin layer was formed to have a haze of 52% by changing the content of the zinc oxide wire rod . Comparative example 1

A polarizing plate was prepared in the same manner as in Example 1 except that a laminate of antireflection layer/PET film/adhesive layer/PET film/polarizer/COP film was prepared. The adhesive layer is formed of an acrylic pressure-sensitive composition. Comparative example 2

A polarizing plate was prepared in the same manner as in Example 1 except that the orientation angle (θ) was changed to 30°. Comparative example 3

A polarizing plate was prepared in the same manner as in Example 1 except that the orientation angle (θ) was changed to 60°. Comparative example 4

A polarizing plate was prepared in the same manner as in Example 6 except that the zinc oxide wire was not added to the first resin layer. Comparative Example 5

A polarizing plate was prepared in the same manner as in Example 1 except that a zinc oxide rod (aspect ratio: 1.3) was used instead of the zinc oxide wire.

The following properties of each of the polarizing plates prepared in Examples and Comparative Examples were evaluated using a model for measuring a viewing angle. The results are shown in Table 2. Light source side polarizer

A polarizer was prepared by stretching a polyvinyl alcohol film to 3 times its original length at 60°C, and adsorbing iodine to the stretched film, and further stretching the film at 40°C in boric acid aqueous solution Stretch to 2.5 times. As a base layer, a triacetyl cellulose film (thickness: 80 μm) is bonded to both surfaces of the polarizer via an adhesive for polarizers (Z-200, Nippon Goshei Co., Ltd.) , to make polarizers. The manufactured polarizing plate was used as a light source side polarizing plate. Viewer side polarizer

As the viewer-side polarizing plate, the polarizing plates prepared in Examples and Comparative Examples were used. Modules for LCD Displays

A light source side polarizing plate is adhesively attached to the lower surface of the liquid crystal panel, and a viewer side polarizing plate is adhesively attached to the upper surface thereof. Here, the antireflection layer of the viewer's side polarizing plate was placed as the outermost layer on the upper surface of the liquid crystal panel. A module for a liquid crystal display is prepared by placing a backlight unit under a polarizing plate on a light source side.

Brightness in white mode and black mode was measured from the front side (0°) to the right side (90°) and left side (-90°) in the spherical coordinate system using EZContrast X88RC (EZXL-176R-F422A4, ELDIM Co., Ltd.).

The relative luminance was calculated according to the equation: (luminance in white mode at the front side of each of the polarizing plates prepared in Examples and Comparative Examples)/(in white at the front side of the polarizing plate prepared in Comparative Example 1 mode) × 100.

The relative lateral contrast ratio was calculated according to the equation: (ratio of luminance in white mode to luminance in black mode at the lateral side (60°) of each of the polarizing plates prepared in Examples and Comparative Examples)/ (ratio of luminance in white mode to luminance in black mode at the lateral side (60°) of the polarizing plate prepared in Comparative Example 1)×100.

Relative brightness x relative lateral contrast ratio can be obtained from the product of relative brightness and relative lateral contrast ratio.

After attaching the viewer-side polarizing plate to the upper surface of the liquid crystal panel, white haze was evaluated in an off (black) state based on the degree of haze via naked eyes. Level 1 is rated as mild; Level 5 is rated as severe; and Level 1 or Level 2 is rated as serviceable. Table 2 example comparative example 1 2 3 4 5 6 7 1 2 3 4 5 first resin layer wire wire wire wire wire wire wire - wire wire - rod Content in the first lipid layer (wt%) 4.9 4.9 9.8 9.8 9.8 4.9 9.8 - 4.9 9.8 - 9.8 Alignment angle (θ, °) 0 90 0 20 70 0 0 - 30 60 - 0 Haze (%) 17 17 32 32 32 41 52 - 17 32 31 39 ΔD (μm) 80 80 80 80 80 80 80 - 80 80 - 80 Relative Brightness (%) 95 95 92 92 92 82 80 100 95 95 83 81 Relative horizontal contrast ratio (%) 115 116 124 118 117 136 144 100 103 102 121 106 Relative Brightness × Relative Horizontal Contrast Ratio 1.09 1.10 1.14 1.09 1.08 1.11 1.15 1.00 0.98 0.97 1.00 0.85 white turbidity 1 1 2 2 2 2 2 1 2 3 2 4

As shown in Table 2, the polarizing plates of the Examples had a value of relative brightness×relative side contrast ratio of 1.05 or greater, thereby improving lateral visibility while minimizing loss of front side brightness. In addition, the polarizing plates of Examples had a low degree of white turbidity, thereby ensuring good appearance of the liquid crystal display. In particular, the polarizing plates of Examples 1 to 5 allow eliminating the patterning process of the polarizing plate, thereby improving the processability and economic feasibility of the polarizing plate.

On the contrary, the polarizing plate of Comparative Example 1 provided lower lateral visibility although relative brightness was higher. In addition, each of the polarizing plates of Comparative Example 2 to Comparative Example 4 had a low value of relative luminance×relative lateral contrast ratio. In addition, the polarizing plate of Comparative Example 5 had a low value of relative luminance×relative to lateral contrast ratio and a high degree of white haze, thereby providing poor appearance.

It should be understood that various modifications, changes, alterations and equivalent embodiments can be made by those skilled in the art without departing from the spirit and scope of the present invention.

10: wire 20: Matrix 100: Polarizer 200, 210: the first resin layer 211: Embossed optical pattern 212: Separation surface 213: inclined surface 214: First facet 300: first protective layer 400: second protective layer 500: The third layer of protection 600: second resin layer L, W1, W2: Maximum width H: height θ1: bottom angle ΔD: distance

FIG. 1 is a cross-sectional view of a polarizing plate according to one embodiment of the present invention. FIG. 2 is a conceptual diagram of a distance ΔD in the polarizing plate of FIG. 1 . FIG. 3 is a cross-sectional view of a polarizing plate according to another embodiment of the present invention. FIG. 4 is a cross-sectional view of a polarizing plate according to yet another embodiment of the present invention. FIG. 5 is a conceptual diagram of a distance ΔD in the polarizing plate of FIG. 4 . FIG. 6 is a diagram of a modification of the embossed optical pattern of the polarizing plate of FIG. 4 . FIG. 7 is a cross-sectional view of a polarizing plate according to still another embodiment of the present invention.

10: wire

20: Matrix

100: Polarizer

200: first resin layer

300: first protective layer

400: second protective layer

Claims (23)

A polarizing plate, comprising: a polarizer; and a first resin layer formed on at least one surface of the polarizer, Wherein the first resin layer includes at least one selected from wires and fibers, and at least some of the at least one selected from the wires and the fibers is relatively light-emitting with respect to the polarizer The absorption axes are aligned at an orientation angle (θ) of 65° to 115° or at an orientation angle (θ) of 0° to 25°. The polarizing plate according to claim 1, wherein the first resin layer is a contrast ratio and/or visibility enhancing layer. The polarizing plate according to claim 1, wherein the total amount of the wires and the fibers in the first resin layer is 60% by weight or more with respect to the light absorption axis of the polarizer aligned at the orientation angle (θ). The polarizing plate according to claim 1, wherein 80% by weight or more of the wires and the fibers are independently dispersed in the first resin layer. The polarizing plate according to claim 1, wherein the first resin layer is separated from the polarizer by a distance (ΔD) of 0 micrometers to 200 micrometers. The polarizing plate according to claim 1, wherein the first resin layer has a refractive index of 1.40 to 1.80. The polarizing plate according to claim 1, wherein the wire or the fiber has an aspect ratio of 500 or less. The polarizing plate according to claim 1, wherein the at least one selected from the wires and the fibers is present in the first resin layer in an amount of 1% by weight to 40% by weight. The polarizing plate according to claim 1, wherein the first resin layer further includes a matrix in which at least one selected from the wires and the fibers is embedded, and is selected from the The at least one of the wire and the fiber has a higher refractive index than the matrix. The polarizing plate according to claim 1, wherein the first resin layer has a haze of 40% or less. The polarizing plate according to claim 1, wherein the at least one selected from the wire and the fiber is formed from at least one selected from the following: metal, metal oxide, metal sulfide, Metal nitrides, metal hydroxides, and glasses. The polarizing plate according to claim 11, wherein the at least one selected from the wire and the fiber is formed of zinc oxide. The polarizing plate according to claim 1, wherein the at least one selected from the wire and the fiber is formed from at least one selected from the following: non-metal, non-metal oxide, non-metal Sulfides, non-metal nitrides, and non-metal hydroxides. The polarizing plate according to claim 1, comprising: the polarizing film; and the first resin layer and the first protective layer, which are sequentially stacked on the light emitting surface of the polarizing film. The polarizing plate according to claim 14, wherein the light exit surface of the first resin layer is flat over the entire surface thereof. The polarizing plate according to claim 15, wherein the first resin layer directly contacts the first protective layer, and the laminate of the first resin layer and the first protective layer has a ratio of 60% or less. of haze. The polarizing plate as described in claim item 14, further comprising: The second resin layer is stacked on one surface of the first resin layer or on the other surface of the first resin layer. The polarizing plate according to claim 17, wherein a patterned portion is formed at an interface between the first resin layer and the second resin layer. The polarizing plate according to claim 18, wherein the patterned portion comprises an embossed optical pattern and a separation surface directly adjacent to the embossed optical pattern. The polarizing plate of claim 19, wherein the inclined surface of the embossed optical pattern comprises a single flat, curved or angled flat surface. The polarizing plate according to claim 18, wherein the second resin layer has a higher refractive index than the first resin layer. The polarizing plate according to claim 17, wherein a laminate of the first resin layer, the second resin layer, and the first protective layer has a haze of 60% or less. An optical display device, comprising the polarizing plate according to any one of claim 1 to claim 22.

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