Polarizers and liquid crystal display devices

The present application provides a polarizer and a liquid crystal display device. The polarizer includes a resin layer, the resin layer includes a whisker, an acute angle is formed by a long-axis direction of each of the whiskers and a bottom surface of the resin layer, and the acute angle is greater than 0° and less than or equal to 40°.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a national phase application of International Application No. PCT/CN2023/101709 field on Jun. 21, 2023, which claims priority to and the benefit of Chinese Patent Application No. 202310394580.6, filed on Apr. 13, 2023. The contents of the aforementioned applications are incorporated herein by reference in their entireties.

TECHNICAL FIELD

The present application relates to display technologies, and more particularly, to polarizers and liquid crystal display devices.

BACKGROUND

In a current polarizer, whiskers are dispersed in film layers of the polarizer, thereby enhancing a viewing angle of the polarizer.

However, in such a polarizer, performance on the viewing angle of the polarizer is expected to be further improved.

Technical Problem

In view of above, the present application provides polarizers and liquid crystal display devices of which the performance on the viewing angle is improved.

Technical Solutions

The present application provides a polarizer including a resin layer, the resin layer includes whiskers, an acute angle is formed by a long-axis direction of each of the whiskers and a bottom surface of the resin layer, and the acute angle is greater than 0° and less than or equal to 40°.

In one embodiment, the acute angle is less than or equal to 20°.

In one embodiment, the whiskers include a first particle and a second particle, the first particle has a diameter constant in a length direction of the first particle, the second particle includes a first end portion and a second end portion arranged in a length direction of the second particle, and the first end portion has a diameter that decreases with an increasing distance from the second end portion in the length direction of the second particle.

In one embodiment, a diameter of the second particle decreases in a direction from the second end portion toward the first end portion.

In one embodiment, the second end portion has a diameter that decreases with an increasing distance from the first end portion in the length direction of the second particle.

In one embodiment, the second particle further includes an intermediate portion, and the first end portion, the intermediate portion, and the second end portion are connected in sequence;

the intermediate portion has a diameter constant in the length direction of the second particle, and the second end portion has a diameter that decreases or constant with an increasing distance from the first end portion in the length direction of the second particle.

In one embodiment, a ratio of a sum of masses of the first particles and the second particles to mass of the resin layer is 10%;the second particles include first-type particles and second-type particles, each of the first-type particles and the second-type particles includes a first end portion and a second end portion arranged in a length direction thereof;a diameter of each of the first-type particles decreases in a direction from the second end portion of the first-type particle toward the first end portion of the first-type particle;a diameter of the second end portion of the second-type particles decreases with an increasing distance from the first end portion of the second-type particles in the length direction of the second-type particles; anda ratio of mass of all the first particles, mass of all the first-type particles, and mass of all the second-type particles is (1 to 10):(40 to 70):(20 to 60).

In one embodiment, the resin layer further includes a first polymer, the whiskers are dispersed in the first polymer, a second polymer is attached to a surface of each of the whiskers, and the first polymer is a lipophilic polymer and the second polymer is a lipophilic polymer.

In one embodiment, the second polymer includes a same group as the first polymer, or the second polymer includes a same group as a homologue of the first polymer; and/orthe second polymer includes at least one of at least one of polyacrylate group, acrylate-acrylic acid copolymer group, polycarboxylic acid-type water-soluble comb copolymer group, or polydimethylsiloxane group.

The present application also provides a liquid crystal display device including the polarizer as described above.

Beneficial Effects

In the polarizer according to an embodiment of the present application, since the length of the whisker is unchanged, the amount of the light scattered by the whisker is unchanged. The amount of light scattered by the whisker may be divided into a component of the scattered light in a direction parallel to the bottom surface of the resin layer (referred to as a left-right component for short) and a component of the scattered light in a direction perpendicular to the bottom surface of the resin layer (referred to as upper-lower component for short). If the left-right component is larger, the up-down component is lesser. The smaller the angle formed by the whisker and the resin layer, the larger the left-right component (i.e., the larger the projection of the whisker on the resin layer), the stronger the left-right scattering, the better the left-right viewing angle performance, and vice versa. The present application improves the viewing angle performance of the polarizer by setting the acute angle formed by the long-axis direction of the whisker and the bottom surface of the resin layer to be greater than 0° and less than or equal to 40°.

DETAILED DESCRIPTION

Technical solutions of embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application: Apparently, the described embodiments are only a part of the embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person skilled in the art without involving any inventive effort fall within the scope of the present application.

In the present disclosure, unless otherwise clearly defined and limited, a first feature “on” or “under” a second feature may mean that the first feature directly contacts the second feature, or that the first feature contacts the second feature via an additional feature therebetween instead of directly contacting the second feature. Moreover, the first feature “on”, “above”, and “over” the second feature may mean that the first feature is right over or obliquely upward over the second feature or mean that the first feature has a horizontal height higher than that of the second feature. The first feature “under”, “below”, and “beneath” the second feature may mean that the first feature is right beneath or obliquely downward beneath the second feature or mean that the horizontal height of the first feature is lower than that of the second feature. Furthermore, the terms “first”, and “second” are for illustrative purposes only and are not to be construed as indicating or imposing a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature that is limited by “first”, or “second” may expressly or implicitly include at least one of the features.

Referring toFIG.1, some embodiments of the present application provide a polarizer100that may be used in a liquid crystal display (LCD). A liquid crystal display device has a liquid crystal cell in which a liquid crystal layer is encapsulated between an array substrate and a color filter substrate. When an electric field is applied to electrodes on the array substrate and the color filter substrate, alignments of liquid crystal molecules of the liquid crystal layer between the array substrate and the color filter substrate change, thereby displaying an image. Polarizers are disposed on outer sides of the array substrate and the color filter substrate. The polarizer selectively transmits light traveling in a specific direction among incident light from a backlight unit or light transmitted through the liquid crystal layer, so that polarization may be controlled.

The polarizer100includes a resin layer10including whiskers101. Referring toFIG.2, the thickness of the resin layer10is H, the length of the whisker101is L, and an acute angle α1formed by a long-axis direction of the whisker101and a bottom surface10aof the resin layer10is in a range of −arcsin (H/L) to arcsin (H/L). It has been found that the acute angle α1affects the performance on the viewing angle of the polarizer100.

In an embodiment, the whisker101is added into the polarizer100, and when the acute angle formed by the long-axis direction of the whisker101and the bottom surface10ais greater than 0° and less than or equal to 40°, the improvement of the luminance viewing angle and the chrominance viewing angle is facilitated. In an embodiment, since each of the whiskers101has the same length, the amount of light scattered by the whisker101is a constant value. The amount of light scattered by the whisker101may be divided into a component of the light scattered by the whisker101in a direction parallel to the bottom surface of the resin layer10(referred to as a left-right component for short) and a component of the light scattered by the whisker101in a direction perpendicular to the bottom surface of the resin layer10(referred to as an up-down component for short). If the left-right component is larger, the up-down component is lesser. The smaller the angle formed by the whisker101and the resin layer10, the larger the left-right component (i.e., the larger the projection of the whisker101on the resin layer10), the stronger the left-right scattering, the better the left-right viewing angle performance, and vice versa.

Further, the experimental results show that when the acute angle α1formed by the long-axis direction of the whisker101and the bottom surface10ais less than or equal to 20°, The luminance viewing angle and the chrominance viewing angle of the display device are further improved.

It should be noted that the polarizer100may include a plurality of film layers (not shown inFIG.1) stacked in sequence. The plurality of sequentially laminated film layers of the polarizer100include a polarizing function layer, and the resin layer10is provided on a side of the polarizing function layer or the polarizing function layer is a resin layer10. The thickness of the resin layer10refers to the thickness in a direction along which the plurality of film layers are laminated. The resin layer10includes a bottom surface10aand a top surface10bopposite to each other in the direction along which the plurality of film layers are laminated. Alternatively, the bottom surface10ais located on a light incidence side of the top surface10b, or the bottom surface10ais the surface formed before the resin layer10is formed.

Alternatively, the whisker101is a cylinder or pyramid, e.g., a cylinder, an elliptical column, a triangular prism, a tetragonal prism, a polygonal prism, a triangular pyramid, a tetragonal pyramid, or a polygonal pyramid. The long-axis direction of the whisker101indicates a height direction of the cylinder or cone, and the length L indicates a length in the height direction of the cylinder or cone, also referred to as the length in the long-axis direction.

Alternatively, the resin layer10includes a first resin layer and a second resin layer. The whisker101is included only in the first resin layer, and the second resin layer does not include the whisker101. This resin layer10is formed by first dispersing whiskers101in a resin composition, forming a first resin layer by coating to set an angle of the whisker101in the first resin layer, and then forming a second resin layer on the first resin layer by coating. The resin layer10of a predetermined thickness is formed by both the first resin layer and the second resin layer. By controlling the thickness of the first resin layer and the length L of the whisker101, the acute angle α1of the whisker101in the first resin layer may be determined, thereby determining the acute angle α1of the whisker101in the resin layer10. For example, if the whisker101having a length of 30 μm is mixed with the resin composition, the first resin layer of 5 μm is formed on the intermediate substrate by coating the mixture, and the second resin layer of 20 μm is formed on the first resin layer, a resin layer10having a thickness of 25 μm may be obtained in which the acute angle α1formed by the long-axis direction of the whisker101and the bottom surface10ais arcsin (5/30)=9.59°, and so on. It will be appreciated that the acute angle α1may be slightly errored within the range allowed by the process.

Alternatively, the material of the whisker101is selected from at least one of compounds: metal oxides such as titanium oxide (e.g., TiO2), zirconium oxide (e.g., ZrO2), or zinc oxide (e.g., ZnO); metal compounds such as calcium carbonate (CaCO3); boehmite; aluminum borate (e.g., AlBO3); calcium silicate (e.g., CaSiO3, wollastonite); magnesium sulfate (MgSO4); magnesium sulfate hydrate (e.g., MgSO4·7H2O) and potassium titanate (e.g., K2Ti8O17) glasses and synthetic resin. Further, the material of the whisker101is selected from at least one of titanium oxide, zirconium oxide, zinc oxide, calcium carbonate, boehmite, aluminum borate, calcium silicate, magnesium sulfate, magnesium sulfate hydrate, and potassium titanate.

Alternatively, the length L of the whisker101is in a range of 3 micrometers to 30 micrometers and the diameter of the whisker101is in a range of 0.003 micrometers to 13 micrometers. It should be noted that the whiskers101may not necessarily have the same length even if they are manufactured in a same process. In the present application, the size of the whiskers101is not limited herein, as long as the size of the whiskers101is in the above-mentioned range.

If the size of the whisker101is too less, a scattering effect is not achieved. If the size of the whisker101is too great, due to the limited thickness (ten or so micrometers to dozens of micrometers) of the film layers of the resin layer10, the whisker101in the resin layer10protrudes from the resin layer10, thereby affecting the flatness of the film layer. In addition, if the length of the whisker101is too great, the whisker101is prone to excessive aggregation, thereby affecting the appearance of the resin layer10.

Referring toFIGS.3and4, the whisker101includes first particles2and second particles3. Each first particle2has a diameter constant in a length direction of the first particle2. Each of the second particle3includes a first end portion D1and a second end portion D2provided in a length direction thereof, and the first end portion D1has a diameter that decreases with an increasing distance from the second end portion D2in the length direction of the second particle. A length direction of the particle is a long-axis direction thereof.

In an embodiment of the present application, the first particles2and the second particles3are provided in the resin layer10of the polarizer100, so that the polarizer100has a scattering effect, and the display panel to which the polarizer100is attached has a better contrast ratio. The first particles2have a diameter constant in a length direction of the first particle2. Each of the second particle3includes a first end portion D1and a second end portion D2provided in a length direction thereof, and the first end portion D1has a diameter that decreases with an increasing distance from the second end portion D2in the length direction. The polarizer100has a scattering effect due to the first particles2or the second particles3, and the chromaticity viewing angle of the display panel to which the polarizer100is attached may be improved. The mixing of the second particles3and the first particles2may reduce the influence of one of the second particles3and the first particles2on the contrast ratio of the display panel to which the polarizer100is attached, so that the display panel to which the polarizer100is attached has a better contrast.

Note that the contrast ratio in the present application refers to a ratio of luminance in a bright state of the display panel to luminance in a dark state of the display panel. If only the first particle2of the constant diameter is provided, that is, only cylindrical particles are provided, in the polarizer100, the cylindrical particles have a good scattering effect. In the dark state, ambient light is scattered by the first particles2, and the luminance of the display panel is greater. In the bright state, the light emitted by the light-emitting unit is scattered by the first particles2, and the luminance of the display panel is lesser due to uniform diffusion. Therefore, the contrast ratio of the display panel is significantly reduced by combining the above influences. The scattering effect of the second particle3, of which the first end portion D1has the diameter that decreases with the increasing distance from the second end portion D2in the length direction, is weaker than that of the first particle2. Both the first particle2and the second particle3are provided in the polarizer100. Therefore, in the dark state, the ambient light is scattered by the mixed particles, and the luminance of the display panel is lesser. In the bright state, the light emitted by the light-emitting unit is scattered by the mixed particles, so that the luminance of the display panel is greater. As a result, the polarizer100has a scattering effect, while the contrast ratio of the display panel to which the polarizer100is attached is less affected by the particles, so that the contrast is improved.

In addition, only the first particle2having the constant diameter is provided, that is, only a cylindrical particle is provided, in the polarizer100, and the light transmittance of the polarizer100, in which only the first particle2of the constant (that is, only cylindrical particles are provided) is slightly lower than that of the polarizer100in which the first particle2and the second particle3are mixed.

In an embodiment as shownFIG.5, the diameter of the second particle3decreases in a direction from the second end portion D2toward the first end portion D1. That is, each of the second particles3has a long cone-shaped shape.

It will be appreciated that the scattering effect of the second particle3of the long cone-shaped shape is weaker than that of the first particle2. Therefore, by mixing the second particles3and the first particles2in the resin layer10, the polarizer100may have a scattering effect, while the contrast ratio of the display panel to which the polarizer100is attached may be less affected by the particles, so that the contrast ratio may be improved.

In the present embodiment, the diameter of the first particle2is in a range of 0.008 μm to 12.4 μm. Each second particle3has a maximum diameter of 12.4 μm and a minimum diameter of 0.008 μm.

In an embodiment, the diameter of the first particle2may be 0.008 micrometers, 0.01 micrometers, 0.05 micrometers, 0.1 micrometers, 0.5 micrometers, 1 micrometer, 1.4 micrometers, 2 micrometers, 2.5 micrometers, 3 micrometers, 3.6 micrometers, 5 micrometers, 5.7 micrometers, 6 micrometers, 8 micrometers, 9 micrometers, 10 micrometers, 11 micrometers, 12 micrometers, 12.4 micrometers, etc. It will be readily appreciated that the first particle2having a diameter constant in a length direction of the first particle2indicates that the cylindrical particles have a diameter deviation within ±20%. For example, the diameter of the first particle2is in a range of 1 micrometer to 3 micrometers with a deviation of ±20%, that is, the diameter ranges from 0.8 micrometers to 1.2 micrometers.

Alternatively, the ratio of the length to radius of the particles is greater than 1. In an embodiment, the ratio of the length to the radius of the particles may be 1.5, 2, 2.5, 3, 5, etc.

In an embodiment of the present application, the diameter of the first particle2is in a range of 0.008 μm to 12.4 μm, the maximum diameter of the second particle3is 12.4 μm, and the minimum diameter of the second particle3is 0.008 μm, so that the light passing through the resin layer10may be subjected to Mie scattering, and the scattering effect may be improved. The resin layer10may be attached to the display panel to improve the chromaticity viewing angle.

In an embodiment, scattering includes Mie scattering and Rayleigh scattering. Mie scattering means that when light is incident onto a particle with a diameter comparable to or larger than the wavelength of light, the light is scattered mainly towards the direction in which it was traveling. That is, the intensity of a portion of the scattered light traveling along a first direction in which the light was traveling is greater than the intensity of a portion of the scattered light traveling along a second direction opposite to the first direction. The light subjected to Rayleigh scattering is scattered uniformly in both the first direction and the second direction. That is, along the direction in which the light was traveling, the intensity of the light subjected to Rayleigh scattering is less than the intensity of the light subjected to Mie scattering. Therefore, the light passing through the resin layer10is subjected to Mie scattering, thereby achieving a good scattering effect and reducing light loss.

Mie scattering and Rayleigh scattering are generally distinguished by the wavelength of the light and the size of the particle, and different processing methods are used depending on the relative relationship between the size of the particle and the wavelength of the light. In an embodiment of the present application, a dimensionless scale is used as a criterion, and the dimensionless scale is a function of the ratio of the radius of the particle to the wavelength of the light, and the formula is: α=2πr/λ. Where α is a dimensionless scale, r is the radius of the particle, and λ is the wavelength of the light. When the diameter of the particle is in a range of 0.008 μm to 12.4 μm, that is, the radius of the particle is in a range of 0.004 μm to 6.2 μm, the dimensionless scale α is greater than or equal to 0.1, and a is less than 50. That is, when the dimensionless scale α is within this range, the light is subjected to Mie scattering. When the dimensionless scale α is much less than 0.1, the light is subjected to Rayleigh scattering. The intensity of the scattered light is a function of the ratio of the radius of the particle to the wavelength of the light.FIG.6is a schematic diagram of the intensity of the scattered light versus the value of the dimensionless scale, where the horizontal coordinate is a, and the vertical coordinate is the intensity I of the scattered light. When the dimensionless scale α is greater than or equal to 0.1, the intensity I of the scattered light increases with the increase of the dimensionless scale α, until it increases to and stabilizes at 1. In the present embodiment, the ratio of the mass of all the first particles2to the mass of all the second particles3is (1 to 10):(90 to 99). In an embodiment, the ratio of the mass of all the first particles2to the mass of all the second particles3may be 1: 99, 2: 98, 3: 97, 4: 96, 5: 95, 6: 94, 7: 93, 8: 92, 9: 91 or 10: 90.

It will be appreciated that the ratio of the mass of all the first particles2to the mass of all the second particles3is in the above range, such that after the polarizer100is attached to the display panel, the chromaticity viewing angle is greater and the contrast ratio is greater.

Referring toFIGS.7and8, an embodiment of the present application provides a polarizer100. The polarizer100differs from the polarizer in the embodiment with reference toFIG.1in that the second end portion has a diameter that decreases with an increasing distance from the first end portion in the length direction of the second particle. In another word, the diameter of the second particle gradually decreases in the direction from the middle of the second particle to the second end portion and in the direction from the middle of the second particle to the first end portion. That is, each second particle3in the present embodiment have a biconical shape.

It will be appreciated that the scattering effect of the biconical second particles3is weaker than that of the first particles2. Therefore, by mixing the second particles3and the first particles2in the resin layer10, the polarizer100has a scattering effect, while the contrast ratio of the display panel to which the polarizer100is attached is less affected by the particles, so that the contrast ratio is improved.

Referring toFIGS.9and10, an embodiment of the present application provides a polarizer100. This embodiment differs from the embodiments with reference toFIGS.3and7in that the second particle3further includes an intermediate portion D3, and the first end portion D1, the intermediate portion D3and the second end portion D2are connected in sequence. The intermediate portion D3has a diameter constant in a length direction of the second particle3. The diameter of the second end portion D2decreases with the increase of a distance from the intermediate portion D3. That is, the second particle3in the present embodiment includes a particle that is cylindrical in the middle thereof and conical at both ends therefore.

It will be appreciated that the scattering effect of the second particle3, which is cylindrical in the middle and conical at both ends, is weaker than that of the first particle2. Therefore, by mixing the second particles3and the first particles2in the resin layer10, the polarizer100has a scattering effect, while the contrast ratio of the display panel to which the polarizer100is attached is less affected by the particles, so that the contrast ratio is improved.

Referring toFIGS.11and12, another embodiment of the present application provides a polarizer100. This embodiment differs from the embodiment with reference toFIG.3in that the second particle3further includes an intermediate portion D3, and the first end portion D1, the intermediate portion D3, and the second end portion D2are connected in this order. Each of the intermediate portion D3and the second end portion D2has a diameter constant in a length direction of the second particle3. That is, the second particle3in the present embodiment further includes a particle in which the first end portion D1is conical and the remaining portion is cylindrical.

It will be appreciated that the scattering effect of the second particle3in which the first end portion D1is conical and the remaining portion is cylindrical. is weaker than that of the first particles2. Therefore, by mixing the second particles3and the first particles2in the resin layer10, the polarizer100has a scattering effect, while the contrast ratio of the display panel to which the polarizer100is attached is less affected by the particles, so that the contrast ratio is improved.

Referring toFIGS.13and14, a yet another embodiment of the present application provides a polarizer100, which differs from the embodiments with reference toFIGS.3and7in that the second particle3includes a first-type particle3aand a second-type particle3b. Each of the first-type particles3aand the second-type particles3bincludes a first end portion D1and a second end portion D2arranged in a length direction thereof. The diameter of each of the first-type particles3adecreases in the direction from the second end portion D2of the first-type particles3atoward the first end portion D1of the first-type particles3a. The diameter of the first end portion D1of the second-type particles3bdecreases with an increasing distance from the second end portion D2of the second-type particles3bin the length direction. The diameter of the second end portion D2of the second-type particles3bdecreases with an increasing distance from the first end portion D1of the second-type particles3bin the length direction. That is, the second particle3in the present embodiment includes a long cone-shaped particle and a biconical particle.

It will be appreciated that the scattering effect of the second particles3including the long cone-shaped first-type particles3aand the biconical second-type particles3bis weaker than that of the first particles2. Therefore, by mixing the second particles3and the first particles2in the resin layer10, the polarizer100has a scattering effect, while the contrast ratio of the display panel to which the polarizer100is attached is less affected by the particles, so that the contrast ratio is improved.

It should be noted that the second particles3in various embodiments of the present application may be combined in any combination. For example, the second particles3may include a long cone-shaped particle and a bi-conical particle. For another example, the second particle3may include a long cone-shaped particle, a bi-conical particle, and a particle in which the first end portion D1is conical and the remaining portion is cylindrical. The second particles3may include a bi-conical particle and a particle in which the first end portion D1is conical and the remaining portion is cylindrical. Alternatively, the second particle3is a long cone-shaped particle and a particle in which the first end portion D1and the second end portion D2are a conical particle and the middle portion is a cylindrical particle. The present application is not limited.

In the present embodiment, the ratio of the masses of all the first particles2, the mass of all the first-type particles3a, and the mass of all the second-type particles3bis (1 to 10):(40 to 70):(20 to 60). In an embodiment, the ratio of the mass of all first particles2, the mass of all first particles3a, and the mass of all second particles3bmay be 1: 40: 59, 2: 42: 56, 3: 45: 52, 4: 48: 48, 5: 70: 25, 5: 69: 26, 6: 68: 26, 7: 55: 38, 8: 55: 37, or 9: 52: 39.

It will be appreciated that the ratio of the mass of the first particles2, the mass of the first-type particles3a, and the mass of the second-type particles3bmay be in the above range, such that when the polarizer100is attached to the display panel, the chromaticity viewing angle is greater and the contrast ratio is greater.

Further, the ratio of the mass of all the first particles2, the mass of all the first-type particles3a, and the mass of all the second-type particles3bmay be (50 to 55):(1 to 5):(45 to 50), such that the display panel to which the polarizer100is attached has a chromaticity viewing angle of 160 degrees or more and a contrast ratio of 2800 or more. In an embodiment, the ratio of the mass of all the first particles2, the mass of all the first-type particles3a, and the mass of all the second-type particles3bis 50: 5: 45, 51: 4: 45, 52: 3: 45, 53: 2: 45, or 54: 1: 45.

Alternatively, the ratio of the sum of the masses of the first particles2, the first-type particles3a, and the second-type particles3bto the mass of the polarizer100is 1% to 30%. In an embodiment, the ratio of the sum of the masses of the first particles2, the first-type particles3a, and the second-type particles3bto the mass of the polarizer100is 1%, 2%, 5%, 7%, 8%, 10%, 15%, 20%, or 30%. The ratio of the sum of the masses of the first particles2, the first-type particles3a, and the second-type particles3bto the mass of the polarizer100is in the above range, so that the scattering effect of the polarizer100is greater, and the light transmittance of the polarizer100is greater.

In this embodiment, the ratio of the sum of the masses of the first particles2, the first-type particles3a, and the second-type particles3bto the mass of the polarizer100is 10%, so that the display panel to which the polarizer100is attached may have a chromaticity viewing angle of 160 degrees or more and the light transmittance of the display panel is 4.65% or more.

Alternatively, the material of the resin layer10may be selected from a cellulose ester resin such as triacetylcellulose (TAC) or the like, a cyclic polyolefin resin including amorphous cyclic polyolefin (COP) or the like, a polycarbonate resin, a polyester resin including polyethylene terephthalate (PET) or the like, a polyethersulfone resin, a polysulfone resin, a polyamide resin, a polyimide resin, an acyclic polyolefin resin, a polyacrylate resin including poly(methyl methacrylate) resin or the like, a polyvinyl alcohol resin, a polyvinyl chloride resin, or a polyvinylidene chloride resin. Alternatively, the material of the resin layer10may be selected from a polyurethane resin, an acrylic resin, an epoxy resin, a vinyl resin, and a silicone resin.

Alternatively, the resin layer further includes a first polymer in which the whiskers are dispersed. A second polymer is attached to a surface of the whisker. The first polymer is a lipophilic polymer and the second polymer is a lipophilic polymer. Hereinafter, the whisker, of which the second polymer is attached the surface is also referred to as a polymer-modified whisker for ease of explanation.

In the present embodiment, the first polymer is a lipophilic polymer, and the second polymer is a lipophilic polymer, so that the lipophilicity of the surface of the whisker may be improved and the whisker is more easily dispersed in the first polymer. The lipophilicity of the first polymer, the lipophilicity of the second polymer, and the lipophilicity of the polymer-modified whisker may be determined by a surface tension test, a contact angle test, a wettability test, or the like.

In an embodiment, the dispersibility of the polymer-modified whisker in the first polymer is greater than that of the unmodified whisker in the first polymer, that is, when the unmodified whiskers start to agglomerate after being dispersed in the first polymer of the first mass, the sum mass of the whiskers added into the first polymer is the second mass. When the polymer-modified whisker starts to agglomerate after being dispersed in the first polymer of the first mass by the same dispersion method as that of the unmodified whiskers, the sum mass of the polymer-modified whisker added into the first polymer is the third mass. The mass of whiskers of the polymer-modified whiskers having the third mass is greater than the second mass. That is, before the aggregation occurs, more polymer-modified whiskers may be dispersed in the first polymer of the same mass than the unmodified whiskers.

In some embodiments, the surface of the whisker is modified by using at least one of inorganic cation, inorganic anion, a coupling agent, or a surfactant, i.e., the surface of the whisker is attached with at least one of an inorganic cation group, an inorganic anion group, a coupling agent group, or a surfactant group.

In some embodiments, the surface of the whisker is modified by using at least one of inorganic magnesium salt, inorganic calcium salt, inorganic barium salt, inorganic strontium salt, stearic acid, stearate, sulfonic acid surfactant, thio surfactant, titanate, aluminate, silane, alkyl phosphate, aryl phosphate, alkyl phosphate, aryl phosphate, alkyl alcohol amide phosphate, alkyl alcohol amide phosphate, imidazoline phosphate, imidazoline phosphate, polyphosphate, polyphosphate, and siloxane phosphate. In an embodiment, the surface of the whisker is modified by using at least one selected from the group consisting of magnesium chloride, calcium chloride, barium chloride, strontium chloride, stearic acid, sodium stearate, zinc stearate, sulfonic acid surfactant, thio surfactant, titanate, aluminate, silane, alkyl phosphate, aryl phosphate, alkyl phosphate, aryl phosphate, alkyl alcohol amide phosphate, alkyl alcohol amide phosphate, imidazoline phosphate, imidazoline phosphate, polyphosphate, polyphosphate, and siloxane phosphate. In an embodiment, the surface of the whisker is modified by using at least one of sulfonic acid surfactant and thio-based surfactant. The sulfonic acid surfactant may be selected from at least one of alkyl sulfonates, fluoroalkyl sulfonates. In an embodiment, the sulfonic acid surfactant may be at least one of sodium dodecyl sulfonate, sodium dodecyl benzene sulfonate, and sodium fluorododecyl sulfonate. The thio-based surfactant may be selected from at least one of thiol, fluorigenic thiol. In an embodiment, the thio-based surfactant may be at least one of octanethiol, dodecanethiol, tetradecanethiol, octadecanethiol, fluorooctanethiol, or fluorododecanethiol. When the sulfonic acid surfactant is mixed with the whisker to be surface-modified, a sulfonic acid-based shell layer (such as a benzene ring sulfonic acid-based shell layer) is formed by the sulfonic acid surface-active group on the surface of the whisker, which is favorable for protecting the whisker, enhancing the toughness of the whisker, and reducing the fracture of the polymer-modified whisker formed by the whisker in the first resin composition. When the thio-based surface-active group and the whisker to be surface-modified are mixed, a cross-linked network of O—S—O is formed by the thio-based surface-active group and the hydroxyl group on the surface of the whisker, and the bond energy of O—S—O is relatively greater, which facilitates to protect the whisker and reduce the fracture of the polymer-modified whisker in the process of further connecting the second polymer to the surface of the whisker and then mixing the second polymer with the first polymer to form the resin composition, and improves the optical functions such as the contrast ratio and the luminance due to the polymer-modified whisker. In an embodiment, the surface of the whisker is modified by using at least one of a sulfonic acid surfactant containing a fluorine substituent, a thio-based surfactant containing fluorine substituent, for example, at least one of sodium fluorododecyl sulfonate, fluorooctanethiol, or fluorododecanethiol. The fluorine atom has high stability in the alkyl chain, the bond energy of the carbon-fluorine bond is higher than that of the carbon-carbon bond, and the carbon-fluorine bond has a shielding effect on the carbon-carbon bond, thereby facilitating to protect the carbon-carbon bond, thereby improving the stability of the whisker. Further, after the surface of the whisker is modified by using at least one of inorganic cation, inorganic anion, a coupling agent, or a surfactant, the richness of the group on the surface of the whisker is increased, the attachment sites of second polymers become more, and the diversity of the polymer material for the second polymer is increased.

In some embodiments, the surface of the polymer-modified whisker includes at least one of polyacrylate group, acrylate-acrylic acid copolymer group, polycarboxylic acid-type water-soluble or comb copolymer group, polydimethylsiloxane group. In some embodiments, the second polymer is selected from at least one of polyacrylate group, acrylate-acrylic acid copolymer group, polycarboxylic acid-type water-soluble comb copolymer group, or polydimethylsiloxane group.

In some embodiments, the polycarboxylic acid-type water-soluble comb copolymer group may be a graft polymer formed from comonomers such as polyoxyethylene methyl allyl diether, maleic anhydride, styrene, or the like. The polycarboxylic acid-type water-soluble comb copolymer group may include polyoxyethylene methyl allyl diether group, polymaleic anhydride group, polystyrene group.

In some embodiments, the molecular weight of the monomers forming the second polymer is greater than or equal to 50, and less than or equal to 500.

In some embodiments, the surface of the polymer-modified whisker includes a group same as that of the first polymer. Alternatively, the surface of the polymer-modified whisker includes a group same as the homologue of the first polymer. In some embodiments, the second polymer is the same as the first polymer, or the second polymer is a homologue of the first polymer. The surface of the polymer-modified whisker includes group same as the first polymer, or group same as the homologue of the first polymer, so that the dispersibility of the polymer-modified whisker in the resin composition may be improved, thereby reducing actual amount of polymer-modified whisker, and thereby reducing loss of light exiting from the display device while improving the chromaticity viewing angle of the display device.

The method of attaching the second polymer to the surface of the whisker to form the polymer-modified whisker may include at least one of a physical method or a chemical method. The physical method may include at least one of a sol-gel method, a precipitation method, or a plasma treatment method. The chemical method may include at least one of a heterogeneous coacervation method, a gas phase grafting method, a radiation grafting method, a high temperature grafting method, a photo-initiated grafting method, a melt grafting method, a solution grafting method, a solid phase grafting method, a microencapsulation technique, or a chemical vapor deposition. The second polymer may be bonded to the group of the surface of the whisker through a side chain group, e.g., to form a chemical bond or a hydrogen bond, thereby being attached to the surface of the whisker. The backbone of the second polymer has a certain length to at least partially warp the whisker. In an embodiment, the second polymer completely warps the whisker. The dispersion of the whisker in the second polymer is better than the dispersion of the whisker in the first polymer, thereby making the dispersion of the polymer-modified whisker greater than the dispersion of the whisker in the first polymer.

In some embodiments of the present application, the polymer-modified whisker is obtained by attaching the second polymer to the surface of the whisker, the first polymer is a lipophilic polymer, and the second polymer is a lipophilic polymer. Therefore, the dispersion of the polymer-modified whisker in a resin composition is improved, the actual use amount of the polymer-modified whisker is reduced when the resin composition is applied to a polarizer, and the loss of the light emitted from the display device is reduced while the chromaticity viewing angle of the display device is improved.

It will be appreciated that the material and properties of the resin layer10may vary depending on its particular location in the polarizer.

Hereinafter, polarizers according to various embodiments the present application will be described. The refractive index of the resin layer10is lower than that of the whisker101. Note that the refractive index of the resin layer10refers to the refractive index of the resin matrix of the resin layer10other than the whisker101. For example, the refractive index n1of the whisker101is in a range of 1.6 to 1.7, and the refractive index n2of the resin layer10is in a range of 1.3 to 1.5.

According to some embodiments of the present application, the polarizer100includes a first substrate, a second substrate, and a polarizing function layer, the first substrate and the second substrate are disposed on opposite sides of the resin layer10, respectively, and the polarizing function layer is disposed on one side of the first substrate away from the resin layer. Alternatively, the resin layer10is used as an adhesive layer to adhere the first substrate to the second substrate. Alternatively, the polarizer100further includes an adhesive layer disposed between the first substrate and the resin layer10and adhering the first substrate and the resin layer10.

An embodiment in which the resin layer10is used as the adhesive layer is shown inFIG.15. The polarizer100includes a release film11, a first pressure-sensitive adhesive layer12, an optical compensation layer13, a polarizing function layer14, a first substrate15, a second pressure-sensitive adhesive layer16, a second substrate17, a hard coat layer18, an anti-reflection layer19, and a protection layer20, which are sequentially stacked. In the active state of the polarizer100, the direction from the release film11to the protection layer20is the stacking direction of the film layers in the polarizer100and the incident direction of the light.

The release film11is configured to protect the pressure-sensitive adhesive layer from damage before the polarizer100is attached to the liquid crystal display panel, to avoid the generation of the bubbles during attaching. The release film11may include a polyester film such as a polyethylene terephthalate film, a polyolefin film such as a polyethylene film and a polypropylene film, or a polytetrafluoroethylene-based film, or may include a release-treated film such as a siloxane-based resin, melamine-based resin, or urea-based resin, so that the release film11is easily peeled off.

A first pressure-sensitive adhesive (PSA) layer12is provided on a side of the release film11. The first pressure-sensitive adhesive layer12is an adhesive layer for adhering the release film11to film layers such as a polarizing function layer14provided on the release film11. The material of the first pressure-sensitive adhesive layer12may be, for example, an acrylate resin.

The optical compensation layer13is disposed on a side of the first pressure-sensitive adhesive layer12away from the release film11. The optical compensation layer13may be a compensation layer or a phase difference film, or the like, in which a liquid crystal based compound is coated on the surface of the substrate and oriented and cured.

The polarizing function layer14is disposed on a side of the optical compensation layer13away from the first pressure-sensitive adhesive layer12. The polarizing function layer14may include polyvinyl alcohol. In an embodiment, the polarizing function layer14may include a polyvinyl alcohol film dyed with iodine or a polyene compound obtained by dewatering the polyvinyl alcohol film.

The first substrate15is disposed on a side of the polarizing function layer14away from the optical compensation layer13. The first substrate15is configured to protect the polarizing function layer14and support the film layers above the first substrate15. The first substrate15may include at least one material selected from the group consisting of a cellulose ester resin including triacetylcellulose (TAC) or the like, cyclic polyolefin resin including an amorphous cyclic polyolefin (COP) or the like, polycarbonate resin, polyester resin including polyethylene terephthalate (PET) or the like; polyethersulfone resin, polysulfone resin, polyamide resin, polyimide resin, acyclic polyolefin resin, polyacrylate resin including poly(methyl methacrylate) resin or the like, polyvinyl alcohol resin, and polyvinylidene chloride resin, but not limited thereto. In an embodiment, the material of the first substrate15is PET.

The second pressure-sensitive adhesive layer16is disposed on a side of the first substrate15away from the polarizing function layer14. The second pressure-sensitive adhesive layer16is the same as the first pressure-sensitive adhesive layer12and is an adhesive layer for bonding the first substrate15and the second substrate17. The material of the second pressure-sensitive adhesive layer16may be selected from the materials as listed in the description of the first pressure-sensitive adhesive layer12, and the description thereof is omitted here.

In the present implementations, the whisker101is disposed in the second pressure-sensitive adhesive layer16, that is, the resin layer10is the second pressure-sensitive adhesive layer16.

The second substrate17is disposed on a side of the second pressure-sensitive adhesive layer16away from the first substrate15. The second substrate17is configured to support the film layers above the second substrate17. The material of the second substrate17may be selected from the materials as listed in the description of the first substrate15, and the description thereof is omitted here. In an embodiment, the material of the second substrate17is PET.

The hard coat layer18is provided on a side of the second substrate17away from the second pressure-sensitive adhesive layer16. The hard coat layer18has a high hardness, a waterproof and oil-proof property, and is capable of preventing the surface of the underlying film layers from being scratched and is easier to clean. Alternatively, the hard coat layer18has a pencil hardness greater than or equal to 2H. The hard coat layer18has a higher glass transition temperature, e.g., 70 degrees Celsius to 120 degrees Celsius. The material of the hard coat layer18may be selected from polyurethane resin, acrylate resin, epoxy resin, vinyl resin, or silicone resin.

The anti-reflection layer19(AR, or anti-reflective) is provided on a side of the hard coat layer18away from the second substrate17. The anti-reflection layer19is configured for anti-reflection while preventing scratches. The anti-reflection layer19is, for example, an electric conductor film formed on the surface of the hard coat layer18.

The surface protection layer20is configured to protect the film layer underneath. The surface protection layer20may be a surface protection layer20. The surface protection layer20may be a transparent resin film formed by one or more selected from thermoplastic resin, e.g., a polyolefin-based resin such as a chain-shaped polyolefin-based resin (such as a polypropylene-based resin or the like), a cyclic polyolefin-based resin (such as norbornene-based resin or the like), or the like; a cellulose ester-based resin such as cellulose triacetate and cellulose diacetate; a polyester-based resin such as polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate; a polycarbonate-based resin; and (meth) acrylic resin; or mixtures, copolymers or the like thereof.

In addition to the above-mentioned film layers, the polarizer100may further have another layer such as an antistatic layer, which will not be described one by one herein.

A polarizer200bonded between the first substrate15and the resin layer210by using an adhesive layer is shown inFIG.16. The embodiment with reference toFIG.16differs from the embodiment with reference toFIG.15in that the whisker101is not dispersed in the second pressure-sensitive adhesive layer16, but is dispersed in an additional resin layer210provided on the second pressure-sensitive adhesive layer16. The material of the resin layer210may be selected from a polyurethane resin, an acrylate resin, an epoxy resin, a vinyl resin, and a silicone resin.

According to some implementations of the present application, the polarizer100includes a substrate, a polarizing function layer, and a hard coat layer. The substrate is disposed between the polarizing function layer and the hard coat layer. The resin layer may be used as any one of the substrates, the polarizing function layer, and the hard coat layer.

A polarizer300in which the resin layer310is used as the hard coat layer318is shown inFIG.17. The embodiment with reference toFIG.17differs from the embodiment with reference toFIG.15in that the whisker101is not dispersed in the second pressure-sensitive adhesive layer, but is dispersed in the hard coating layer318. In this embodiment, the second substrate and the second pressure-sensitive adhesive layer may be omitted, and only one substrate315and one pressure-sensitive adhesive layer312may be provided. By omitting the second base material and the second pressure-sensitive adhesive layer, the structure of the polarizer100may be simplified, while the luminance and the contrast ratio of the display panel to which the polarizer is attached are improved by omitting the two base materials.

An embodiment in which the resin layer410is used as the substrate415is shown inFIG.18. The embodiment with reference toFIG.18differs from the embodiment with reference toFIG.17in that in that the whisker101is not dispersed in the hard coat layer18, but is dispersed in the substrate415. In this embodiment, only one substrate415may be provided. In this structure, both the substrate415and the polarizing function layer may be formed in a same stretching process.

An embodiment in which the resin layer510is used as the polarizing function layer514is shown inFIG.19. The embodiment with reference toFIG.19differs from the embodiment with reference toFIG.17in that the whisker101is not dispersed in the hard coat layer18, but is dispersed in the polarizing function layer514. In this embodiment, only one base material may be provided. In this structure, the polarizing function layer514in which the whisker101is mixed may be formed by a stretching process.

Referring toFIG.20, the present application further provides a liquid crystal display device1including a polarizer100and a liquid crystal display panel LCD as described above, the polarizer100/200/300/400/500is disposed on a light exiting side of the liquid crystal display panel LCD. That is, the polarizer100/200/300/400/500of the present application is used as the upper polarizer of the liquid crystal display device1. The liquid crystal display device1further includes a backlight module, a lower polarizer, or the like provided on the light incident side of the liquid crystal display panel LCD, and a description thereof will be omitted here.

Hereinafter, the improvement of the performance on the viewing angle of a liquid crystal display device disposed with the polarizer according to the present application will be described with reference to the following embodiments.

The polarizer as shown inFIG.15is manufactured in which the material of the resin layer was an acrylate resin, and the whisker was a calcium carbonate whisker. The whisker has a refractive index n1of 1.67, a diameter of 1 micrometer to 3 micrometers, and a length L of 10 micrometers to 30 micrometers. The resin layer has a refractive index n2of 1.49, and a thickness H of 25 micrometers. The ratio of the mass of the whiskers to the total mass of the resin layer (including the whisker and a resin base of the resin layer) is 10%. The resin layer is formed by first dispersing whiskers in a resin composition, forming a first resin layer having a thickness of 5 micrometers by coating, setting an angle of the whisker in the first resin layer, and then forming a second resin layer having a thickness of 20 micrometers on the first resin layer by coating. The resin layer having a total thickness of 25 micrometers is formed by The first resin layer and the second resin layer.

A front projection of the whiskers on the bottom surface of the resin layer is parallel to an absorption axis of the polarizing function layer. An acute angle formed by the long-axis direction of the whisker and the bottom surface of the resin layer is less than or equal to 10°.

It should be noted that the whiskers even formed in the same process do not necessarily have the completely same angles formed by the long-axis directions of the whiskers and the bottom surface of the resin layer. In an embodiment of the present application, the angle formed by the long-axis direction of the whisker and the bottom surface of the resin layer is not limited herein, as long as the angle is in a certain range.

The polarizer is attached as an upper polarizer onto the liquid crystal panel for measuring the optical performance of the polarizer, and the optical performance includes light transmittance, luminance in the bright state, luminance in the dark state, a luminance viewing angle (0.5), or a chrominance viewing angle (0.02).

The luminance measured when the polarizer is viewed in front is taken as the central luminance. The luminance decreases as the viewing angle becomes greater, and when the luminance decreases to half of the central luminance, the viewing angle is taken as the luminance viewing angle (0.5). The chromatic viewing angle (0.02) is the viewing angle at which coordinates x and y of the color coordinate are shifted by 0.02, based on a color coordinate measured when the polarizer is viewed in front. The larger the luminance viewing angle (0.5) and the chrominance viewing angle (0.02), the better the viewing angle effect.

The polarizer as shown inFIG.15is manufactured in which the material of the resin layer was an acrylate resin, and the whisker was a calcium carbonate whisker. The whisker has a refractive index n1of 1.67, and a length L of 10 micrometers to 30 micrometers. The resin layer has a refractive index n2of 1.49, and a thickness H of 25 micrometers. The ratio of the mass of the whiskers to the total mass of the resin layer is 10%. The resin layer is formed by first dispersing whiskers in a resin composition, forming a first resin layer having a thickness of 10 micrometers by coating, setting an angle of the whisker in the first resin layer, and then forming a second resin layer of 15 micrometers on the first resin layer by coating. The resin layer having a total thickness of 25 micrometers is formed by The first resin layer and the second resin layer.

A front projection of the whiskers on a bottom surface of the resin layer is parallel to an absorption axis of the polarizing function layer. An acute angle formed by the long-axis direction of the whisker and the bottom surface of the resin layer is less than or equal to 20°.

The polarizer as shown inFIG.15is manufactured in which the material of the resin layer was an acrylate resin, and the whisker was a calcium carbonate whisker. The whisker has a refractive index n1of 1.67, and a length L of 10 micrometers to 30 micrometers. The resin layer has a refractive index n2of 1.49, and a thickness H of 25 micrometers. The ratio of the mass of the whiskers to the total mass of the resin layer is 10%. The resin layer is formed by first dispersing whiskers in a resin composition, forming a first resin layer having a thickness of 15 micrometers by coating, setting an angle of the whisker in the first resin layer, and then forming a second resin layer of 10 micrometers on the first resin layer by coating. The resin layer having a total thickness of 25 micrometers is formed by The first resin layer and the second resin layer.

A front projection of the whiskers on a bottom surface of the resin layer is parallel to an absorption axis of the polarizing function layer. An acute angle formed by the long-axis direction of the whisker and the bottom surface of the resin layer is less than or equal to 30°.

The polarizer as shown inFIG.15is manufactured in which the material of the resin layer was an acrylate resin, and the whisker was a calcium carbonate whisker. The whisker has a refractive index n1of 1.67, and a length L of 10 micrometers to 30 micrometers. The resin layer has a refractive index n2of 1.49, and a thickness H of 25 micrometers. The ratio of the mass of the whiskers to the total mass of the resin layer is 10%. The resin layer is formed by first dispersing whiskers in a resin composition, forming a first resin layer having a thickness of 20 micrometers by coating, setting an angle of the whisker in the first resin layer, and then forming a second resin layer of 5 micrometers on the first resin layer by coating. The resin layer having a total thickness of 25 micrometers is formed by The first resin layer and the second resin layer.

A front projection of the whiskers on a bottom surface of the resin layer is parallel to an absorption axis of the polarizing function layer. An acute angle formed by the long-axis direction of the whisker and the bottom surface of the resin layer is less than or equal to 40°.

The polarizer as shown inFIG.15is manufactured in which the material of the resin layer was an acrylate resin, and the whisker was a calcium carbonate whisker. The whisker has a refractive index n1of 1.67, and a length L of 10 micrometers to 30 micrometers. The resin layer has a refractive index n2of 1.49, and a thickness H of 25 micrometers. The ratio of the mass of the whiskers to the total mass of the resin layer is 10%. A front projection of the whiskers on a bottom surface of the resin layer is parallel to an absorption axis of the polarizing function layer. An acute angle formed by the long-axis direction of the whisker and the bottom surface of the resin layer is less than or equal to 55°. The resin layer in the Embodiment 5 is formed by a coating process.

The parameters and optical properties of the polarizers of Embodiments 1 to 5 are shown in Table 1 below.

As can be seen from Embodiments 1 to 5, as the orientation angle of the whisker decreases, the light transmittance of the polarizer does not change much, but both the luminance viewing angle and the chrominance viewing angle increase with the decrease of the orientation angle.

When the orientation angle is less than or equal to 40°, the luminance viewing angle and the chrominance viewing angle are improved significantly compared with those when the orientation angle is less than or equal to 55°, thereby achieving a better display effect. Further, when the orientation angle is reduced to less than or equal to 20°, the luminance viewing angle and the chrominance viewing angle exhibit a significant improvement.

The polarizer as shown inFIG.15is manufactured by using the following particle contents. the material of the resin layer was an acrylate resin, and the whisker was a calcium carbonate whisker. The whisker has a refractive index n1of 1.67, a diameter of 1 micrometer to 3 micrometers, and a length L of 10 micrometers to 30 micrometers. The resin layer has a refractive index n2of 1.49, and a thickness H of 25 micrometers. The ratio of the mass of the whiskers to the total mass of the resin layer (including the whisker and a resin base of the resin layer) is 10%.

A front projection of the whiskers on a bottom surface of the resin layer is parallel to an absorption axis of the polarizing function layer. An acute angle formed by the long-axis direction of the whisker and the bottom surface of the resin layer is less than or equal to 5°.

It should be noted that L1refers to the first particle2, and the diameter of the first particle2is unchanged in the length direction of the first particle2, that is, the first particle2is the cylindrical particle. L2refers to the second particle3having a diameter decreasing in the direction from the second end portion D2of the second particle3toward the first end portion D1of the second particle3, that is, the second particle3is a long cone-shaped particle. L3refers to the second particle3having a diameter gradually decreasing in the direction from the middle of the second particle3to the second end portion D2and in the direction from the middle of the second particle3to the first end portion D1, i.e., the second particle3is a biconical particle.

Contrast ratio CR refers to the ratio of luminance in the bright state to luminance in the dark state of the display panel. In this test, the luminance of the center of the display panel in the bright state and the luminance of the center of the display panel in the dark state were measured.

The chromaticity viewing angle measurement is a viewing angle measurement performed by the CESI standard (CESI0.03).

Some embodiments of the present application will now be described in further detail with reference to a portion of the test results. Refer to Table 2 for details of the test.

According to Table 2, in Comparative Example 2-3, Comparative Example 2-4, and Comparative Example 2-5, only the first particle2having the constant diameter (i.e., only the cylindrical particle) is provided in the polarizer100. The contrast ratio of the display panel in each of the above comparative examples is significantly lower than that of the display panel in which only the biconical particle is provided in the polarizer100and the display panel in which only the long cone-shaped particle is provided in the polarizer100. The light transmittance of the display panel in each of the above comparative examples is also slightly lower than that of the display panel in which only the biconical particle is provided in the polarizer100and the display panel in which only the long cone-shaped particle is provided in the polarizer100.

From Table 2, by comparing embodiments 2-1 to 2-5 and Comparative Example 2-1, the chromaticity viewing angle of the display panel provided with the polarizer100in which the first particles2and the second particles3are mixed in the adhesive resin layer10is higher than that of the display panel provided with the polarizer100in which only the second particles3are provided in the adhesive resin layer10. The display panel provided with the polarizer100in which the first particles2and the second particles3are mixed in the adhesive resin layer10has a chromaticity viewing angle of 160° or more. By comparing embodiments 2-1 to 2-5 and Comparative Example 2-1, the contrast ratio and light transmittance of the display panel provided with the polarizer100in which the first particles2and the second particles3are mixed in the adhesive resin layer10are both greater than that of the display panel provided with the polarizer100in which only the second particles3are provided in the adhesive resin layer10. The display panel provided with the polarizer100in which the first particles2and the second particles3are mixed in the adhesive resin layer10has a contrast ratio of 2800 or more and a light transmittance of 4.65% or more. Therefore, the polarizer100of the present application has excellent performance and has a good application prospect.

First, a needle-shaped whisker made of CaCO3and ultrapure water were mixed to be a slurry in which the mass fraction of CaCO3is 6%, sodium stearate is dissolved in absolute ethanol having a mass same as the sodium stearate, and the obtained material is dropped into a calcium carbonate slurry at a temperature of 85° C., so that the mass fraction of sodium stearate was 2%, the obtained slurry is stirred with a stirrer for 1 h, filtered, washed by using ultrapure water and absolute ethanol, and dried at a temperature of 110° C., to obtain the whisker of which the surface is modified by sodium stearate.

The whisker of which the surface is modified by sodium stearate is dissolved in anhydrous ethanol in an equal (mass) proportion, 3% by mass of glycidyl methacrylate and 3.5% by mass of dibromoisobutyryl bromide are dropped into the obtained material in this order, and the obtained solution is stirred at 60° C. for 45 min. Then, 1% by mass of cuprous bromide is dropped as a catalyst, 3% by mass of pentamethyldiethylenetriamine (PMDETA) is dropped, and the obtained solution is stirred at constant temperature of 60° C. for 80 min, filtered, washed by using ultrapure water and absolute ethanol, and dried at a temperature of 110° C., to obtain the polymer-modified whisker of which polyglycidylmethacrylate is bond to the outer surface.

The polymer-modified whisker is doped at a mass fraction of 6% in an adhesive material for forming the second pressure-sensitive adhesive layer, to form a resin composition. The resin layer is formed on the surface of the first protection layer by using the resin composition. The resin layer has a thickness of 20 micrometers, and the structure of the polarizer was shown inFIG.15.

Comparative Example 3-1

Different from Embodiment 3-1, the obtained whisker of which the surface is modified by sodium stearate is doped at a mass fraction of 7% in an adhesive material for forming the second pressure-sensitive adhesive layer, to form a comparative resin composition. The comparative resin layer is formed on the surface of the first protection layer by using the comparative resin composition. The comparative resin layer had a thickness of 25 micrometers, thereby obtaining a comparative polarizer. The structure of the comparative polarizer may be same as or similar to that of the polarizer obtained in Embodiment 1, except that in the comparative polarizer, the resin layer was replaced with the comparative resin layer.

The polarizers obtained in Embodiment 3-1 and Comparative Example 3-1 were respectively provided on the light exiting sides of the same type of liquid crystal display modules (including the same liquid crystal display panels, the same backlight modules, and the polarizers of the same structure and each located between the liquid crystal display panel and the backlight module), thereby obtaining the chromaticity viewing angle, the light transmittance, and the yield of the obtained polarizers as shown in Table 3.

From Table 3, as compared to the whisker of which the surface has been modified by sodium stearate, the polymer-modified whiskers formed by attaching a polymer to the surface of the whisker of which the surface has been modified by sodium stearate may improve the dispersibility of the polymer-modified whisker and reduce aggregation in the resin layer due to the polymer attached to the surface of the whisker, so that under the same degree of chromaticity viewing angle, the amount of particles is reduced, the light transmittance of light of the display device is improved, and the product yield is also improved.

The foregoing has provided a detailed description of embodiments of the present application, and some embodiments have been used herein to illustrate the principles and implementations of the present application. The foregoing description of embodiments is provided merely to assist in understanding the present application. At the same time, variations will occur to those skilled in the art in both the detailed description and the scope of the present application in accordance with the teachings of the present application. In view of the foregoing, the present description should not be construed as limiting the application.