Optical film, polarizing plate, and display device

By distributing a second solid phase of different materials in the second base layer of the optical film to form a random interface, the problems of reduced light transmittance and increased cost of anti-glare optical films are solved, and the integration of high light transmittance and mechanical strength is achieved.

CN121028260BActive Publication Date: 2026-06-05TCL CHINA STAR OPTOELECTRONICS TECHNOLOGY CO LTD

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
TCL CHINA STAR OPTOELECTRONICS TECHNOLOGY CO LTD
Filing Date
2025-09-25
Publication Date
2026-06-05

AI Technical Summary

Technical Problem

Existing anti-glare optical films reduce the light transmittance of polarizers and increase manufacturing costs.

Method used

By distributing a second solid phase of different materials in the second base layer of the optical film to form multiple randomly distributed interfaces, the directional reflection of light is reduced. The optical film is then prepared by melt co-extrusion process to ensure that the polarizer has anti-glare function while maintaining high light transmittance and mechanical strength.

Benefits of technology

This technology integrates anti-glare functionality onto the protective substrate of the polarizer, improving light transmittance and mechanical strength while reducing manufacturing costs.

✦ Generated by Eureka AI based on patent content.

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Abstract

The embodiment of the present application discloses an optical film, a polarizer and a display device, comprising a first base layer; and a second base layer located on at least one side of the first base layer; the first base layer has a first solid phase; the second base layer contains at least two second solid phases; among the at least two second solid phases, adjacent two second solid phases are connected to form a plurality of interfaces, the plurality of interfaces are distributed in the second base layer, and the materials of the two second solid phases forming the interfaces are different. The present application distributes a plurality of interfaces in the second base layer, thereby reducing the directional reflection of light on the second base layer, and achieving the anti-dazzling purpose. In addition, the optical film can also provide good light transmittance and high mechanical strength, thereby realizing the integration of the anti-dazzling function in the protective substrate of the polarizer, effectively controlling the thickness and manufacturing cost of the polarizer.
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Description

Technical Field

[0001] This application relates to the field of display technology, specifically to an optical film, a polarizer, and a display device. Background Technology

[0002] A polarizer is an optical element that converts natural light into polarized light. It typically consists of a polarizing layer and a protective substrate layer. To meet everyday applications, a functional layer is usually coated on the surface of the protective substrate layer. To reduce specular reflection and prevent glare from negatively impacting display quality, an anti-glare coating is applied to the protective substrate of the polarizer. This is primarily achieved by adding particles of appropriate size to a resin coating to form an optical film, thereby increasing diffuse reflection and reducing glare. However, the anti-glare optical film also reduces the overall transmittance of the polarizer and increases its manufacturing cost.

[0003] Therefore, new optical films need to be developed to overcome the above problems. Summary of the Invention

[0004] This application provides an optical film, a polarizer, and a display device that can achieve anti-glare function. When applied to the protective substrate of the polarizer, it can ensure that the polarizer has high light transmittance and high mechanical strength, thereby integrating the anti-glare function into the protective substrate of the polarizer and effectively controlling the thickness and manufacturing cost of the polarizer.

[0005] A first aspect of this application provides an optical film, the optical film comprising:

[0006] First-level grassroots;

[0007] as well as,

[0008] The second base layer is located on at least one side of the first base layer;

[0009] Wherein, the first base layer has a first solid phase;

[0010] The second base layer has at least two different second solid phases; at least some of the adjacent second solid phases are in contact to form a plurality of interfaces distributed in the second base layer, and the materials of the adjacent second solid phases forming the interfaces are different.

[0011] Optionally, in the plurality of interfaces, at least a portion of the interfaces are formed by the fusion of adjacent second solid phases at their junctions.

[0012] Optionally, the material of the second solid phase forming the interface includes a resin.

[0013] Optionally, in the at least two different second solid phases, the absolute value of the refractive index difference between at least one of the second solid phases and the first solid phase is less than or equal to 0.2.

[0014] Optionally, in the at least two different second solid phases, at least one of the second solid phases is made of the same material as the first solid phase.

[0015] Optionally, the first base material includes at least one of modified or unmodified polyethylene terephthalate, modified or unmodified polyethylene naphthalate, modified or unmodified polycarbonate, modified or unmodified polymethyl methacrylate, etc.; and / or,

[0016] The material of each of the second solid phases is independently selected from at least one of modified or unmodified polyester materials, modified or unmodified polyolefins, modified or unmodified cellulose, and modified or unmodified polymethyl methacrylate;

[0017] The modified or unmodified polyester material includes at least one of modified or unmodified polyethylene terephthalate, modified or unmodified polyethylene naphthalate, and modified or unmodified polycarbonate.

[0018] The modified or unmodified polyolefin includes at least one of modified or unmodified cyclic olefin copolymers;

[0019] The modified or unmodified cellulose includes modified or unmodified cellulose triacetate.

[0020] Optionally, the at least two different second solid phases include a host solid phase and a plurality of dispersed solid phases; and the second solid phase with an absolute value of the refractive index difference from the first solid phase less than or equal to 0.2 is the host solid phase, and the second solid phase with an absolute value of the refractive index difference from the first solid phase greater than 0.2 is the dispersed solid phase, the plurality of dispersed solid phases are dispersed at different positions of the host solid phase, and each of the dispersed solid phases is in contact with the host solid phase to form the interface; in the second base layer, the mass percentage of the host solid phase is greater than the sum of the mass percentages of the plurality of dispersed solid phases.

[0021] Optionally, in the second base layer, the mass percentage of the main solid phase is 90% to 99.99%, and the sum of the mass percentages of the plurality of dispersed solid phases is 0.01% to 10%.

[0022] Optionally, the optical film further includes an adhesive layer located on the side of the first base layer away from the second base layer, and / or, the adhesive layer is located on the side of the second base layer away from the first base layer;

[0023] The optical film further includes at least one first microparticle;

[0024] The at least one first particle is dispersed in the second base layer, and / or, the at least one first particle is dispersed in the first base layer, and / or, the at least one first particle is dispersed in the adhesive layer.

[0025] Optionally, the material of the first particle is selected from at least one of calcium carbonate, barium sulfate, silicon dioxide, organosilicon, and barium dioxide.

[0026] Optionally, the mass ratio of the at least one first particle to the second base layer is greater than 0 and less than 2%, and / or the mass ratio of the at least one first particle to the adhesive layer is greater than 0 and less than 2%, and / or the mass ratio of the at least one first particle to the first base layer is greater than 0 and less than 2%.

[0027] Optionally, the optical film further includes a third base layer;

[0028] The third base layer is located on the side of the first base layer away from the second base layer, and the third base layer includes a substrate and second particles dispersed in the substrate.

[0029] Optionally, the thickness of the first base layer accounts for 60% to 99% of the thickness of the optical film, and the thickness of the second base layer accounts for 1% to 40% of the thickness of the optical film.

[0030] Optionally, the thickness of the optical film is 10 micrometers to 100 micrometers.

[0031] Optionally, the first base layer and the second base layer are integrally formed.

[0032] Optionally, the in-plane retardation value R0 of the optical film is less than or equal to 3000 nm.

[0033] A second aspect of this application provides a polarizer, the polarizer comprising a polarizing layer and a protective substrate stacked thereon, the protective substrate being the aforementioned optical film, and a first base layer being located between the polarizing layer and a second base layer.

[0034] Optionally, the polarizer further includes a compensation film; the compensation film is located on the side of the polarizing layer away from the protective substrate; and / or,

[0035] The polarizer also includes an anti-reflective layer, which is located on the side of the protective substrate away from the polarizing layer.

[0036] Optionally, the polarization degree of the polarizer is greater than or equal to 99%; and / or,

[0037] The transmittance of the polarizer is greater than or equal to 40%.

[0038] A third aspect of this application provides a display device, the display device comprising:

[0039] A display panel, comprising an incident light side and an emitted light side disposed opposite to each other; and...

[0040] A polarizer is located on the light-incident side and / or the light-outceasing side, the polarizer being the aforementioned polarizer, and the polarizing layer is located between the display panel and the protective substrate.

[0041] This application's optical film includes a first base layer and a second base layer located on at least one side of the first base layer. The first base layer has a first solid phase; the second base layer contains at least two different second solid phases; at least partially adjacent second solid phases are in contact to form multiple interfaces, the multiple interfaces being distributed in the second base layer, and the two second solid phases forming the interfaces are made of different materials. This application achieves reduced directional reflection of light on the second base layer and thus anti-glare by distributing second solid phases of different materials in the second base layer, thereby forming multiple randomly distributed interfaces between adjacent second solid phases. Furthermore, since the first base layer only has a first solid phase, when the second base layer is disposed on the first base layer to form an optical film and applied to the protective substrate of a polarizer, it not only ensures that the polarizer has an anti-glare function but also provides good light transmittance and high mechanical strength, thereby integrating the anti-glare function into the protective substrate of the polarizer and effectively controlling the thickness and manufacturing cost of the polarizer. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a schematic diagram of the structure of an optical film according to an embodiment of this application;

[0044] Figure 2 This is a schematic diagram of the structure of an optical film according to an embodiment of this application;

[0045] Figure 3 This is a schematic diagram of the structure of an optical film according to an embodiment of this application;

[0046] Figure 4 This is a schematic diagram of the structure of an optical film according to an embodiment of this application;

[0047] Figure 5This is a schematic diagram of the structure of a polarizer according to an embodiment of this application;

[0048] Figure 6 This is a schematic diagram of the structure of a polarizer according to an embodiment of this application;

[0049] Figure 7 This is a schematic diagram of the display device structure provided in the embodiments of this application.

[0050] Explanation of reference numerals in the attached figures:

[0051] 10. Optical film; 1. First base layer; 1a. First side; 1b. Second side; 1c. First solid phase; 2. Second base layer; 2a. Second solid phase; 2b. Interface; 3. Third base layer; 301. Substrate; 302. Second microparticle; 4. Adhesive layer; 5. First microparticle; 100. Polarizer; 11. Release film; 12. Pressure-sensitive adhesive layer; 13. Compensation film; 14. First adhesive layer; 15. Polarizing layer; 16. Second adhesive layer; 17. Anti-reflective layer; 18. Surface protective film; 200. Display device; 20. Display panel; 20a. Light-incident side; 20b. Light-emitting side; 100a. Upper polarizer; 100b. Lower polarizer. Detailed Implementation

[0052] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0053] This application provides an optical film, a polarizer, and a display device. These are described in detail below. It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of the embodiments. Furthermore, in the description of this application, the term "comprising" means "including but not limited to". The terms first, second, third, etc., are used merely as illustrative and do not impose numerical requirements or establish an order. Various embodiments of the present invention may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a rigid limitation on the scope of the invention; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single digits within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any referenced number (fraction or integer) within the indicated range.

[0054] Anti-glare optical films reduce the overall transmittance of polarizers and increase the manufacturing cost of polarizers.

[0055] See Figures 1-4 To address the aforementioned issues, this application provides an optical film 10, comprising: a first base layer 1 and a second base layer 2. The first base layer 1 includes a first side 1a and a second side 1b disposed opposite to each other. The second base layer 2 is located on the first side 1a and / or the second side 1b of the first base layer 1 (i.e., the second base layer 2 is located on at least one side of the first base layer 1). The first base layer 1 has a first solid phase 1c. The second base layer 2 has at least two second solid phases 2a. Among the at least two second solid phases 2a, at least some adjacent second solid phases 2a are connected to form a plurality of interfaces 2b. The plurality of interfaces 2b are distributed in the second base layer 2, and the materials of the second solid phases 2a forming the interfaces 2b are different.

[0056] It is understood that in the embodiments of this application, "solid phase" refers to the state in which an object exists in a solid form; furthermore, in the embodiments of this application, the same "solid phase" means that the object has the same solid state, and different "solid phases" mean that the object has different solid states. It is understood that in the implementation of this application, the first base layer only has the first solid phase 1c, that is, the first base layer only has one solid state.

[0057] It is understood that if the first base layer 1 contains solid impurities, these solid impurities must be unavoidable trace amounts (less than 0.01 wt%) that cannot be completely removed by conventional processes in the art; or the first base layer 1 may contain no solid impurities at all. In both of these cases, based on the consistency of the solid state of the first base layer 1, it should be considered that the first base layer 1 only has the first solid phase 1c.

[0058] It is understood that the contact of adjacent second solid phases 2a includes either partial contact of adjacent second solid phases 2a or complete contact of adjacent second solid phases 2a.

[0059] It is understood that in the implementation of this application, multiple interfaces 2b are distributed in different locations in the second base layer 2, and at least some of the interfaces 2b are distributed in the second base layer 2 according to any one or more of the following distribution methods:

[0060] (i) The interface 2b at different locations of the second base layer 2 has different materials;

[0061] (ii) The shape of the interface 2b is different at different positions of the second base layer 2;

[0062] (iii) The extension direction of the interface 2b at different positions of the second base layer 2 is different.

[0063] Furthermore, the interface 2b at different locations of the second base layer 2 has different materials, including different types of materials and / or different contents of the same type of material.

[0064] This application utilizes a second solid phase 2a formed of different materials distributed in the second base layer 2 to create multiple randomly distributed interfaces 2b between adjacent second solid phases 2a. These interfaces 2b disrupt the directional reflection of light, thereby reducing directional reflection of light on the second base layer 2 and achieving anti-glare. Furthermore, since the first base layer 1 has a first solid phase, when the second base layer 2 is disposed on the first base layer 1 to form an optical film 10 and applied to the protective substrate of the polarizer 100, it not only ensures that the polarizer 100 has an anti-glare function but also provides good light transmittance and high mechanical strength. This integrates the anti-glare function into the protective substrate of the polarizer 100. Because no additional anti-glare functional layer is added, the thickness and manufacturing cost of the polarizer 100 can be effectively controlled.

[0065] In some embodiments, the materials of the two second solid phases 2a forming the interface 2b are incompatible.

[0066] It is understood that the incompatibility in the embodiments of this application includes partial incompatibility (i.e., neither completely compatible nor completely incompatible, or it may be partially compatible) or complete incompatibility. In this way, the incompatibility of the materials forms microphase separation, and the separated microphases come together to form interface 2b.

[0067] Traditional doped particles exhibit significant particle-substrate separation, making it difficult to achieve precise control of anti-glare properties. Existing formulations for achieving anti-glare side optical films typically have high requirements, necessitating precise control of particle concentration and dispersion uniformity, resulting in significant process control challenges.

[0068] To address the aforementioned issues, in some embodiments, at least a portion of the plurality of interfaces 2b is formed by the fusion of adjacent second solid phases 2a at their junctions. That is, the fused interface 2b includes a portion of the second solid phase 2a that forms the interface 2b.

[0069] Because the solid phases formed by the fusion of different materials have different refractive indices in the second solid phase 2a of different materials, the refractive index of the interface 2b formed at the fusion part also differs from that of the second solid phase 2a, which can reduce the directional reflection of light on the second base layer 2. Because of the interface 2b formed at the fusion part, there is a transition between different materials at the interface 2b, which helps to achieve precise control of anti-glare and reduce the process difficulty of anti-glare control.

[0070] In some embodiments, the materials of the two second solid phases 2a forming the interface 2b include resin.

[0071] In this embodiment, the second solid phase 2a forming the interface 2b is made of resin. Different materials can be selected and combined according to material compatibility to meet different anti-glare requirements and reduce dependence on dispersion process and concentration.

[0072] In some embodiments, the material of the second solid phase 2a forming the interface 2b is molten resin. When the material of the second solid phase 2a is molten resin, it can be melted to form a liquid mixture and then cooled to form a solid phase. Alternatively, materials of different second solid phases 2a can be melted, partially mixed in a liquid state, and then cooled. During this process, different second solid phases 2a are formed and fused at the junction of adjacent different second solid phases to form an interface 2b. That is, the molten resin forms the interface 2b after being melted and mixed.

[0073] See Figure 1 In some embodiments, the optical film 10 includes two second base layers 2, which are respectively disposed on the first side 1a and the second side 1b.

[0074] In some embodiments, among at least two different second solid phases 2a, the absolute value of the refractive index difference between at least one second solid phase 2a and the first solid phase 1c is less than or equal to 0.2. When the absolute value of the refractive index difference between the first substrate 1 and the second substrate 2 is less than or equal to 0.2, optical loss is reduced, ensuring overall light transmittance.

[0075] In some embodiments, the first base layer 1 is made of one type of material, or the first base layer 1 is made of multiple materials that are compatible with each other, thereby ensuring the uniformity of the first solid phase 1c.

[0076] In some embodiments, at least two different second solid phases 2a include a main solid phase and a plurality of dispersed solid phases. The second solid phase 2a with an absolute value of the refractive index difference with the first solid phase less than or equal to 0.2 is the main solid phase, and the second solid phase 2a with an absolute value of the refractive index difference with the first solid phase 1c greater than 0.2 is the dispersed solid phase. The plurality of dispersed solid phases are dispersed at different positions of the main solid phase, and each dispersed solid phase forms an interface 2b with the main solid phase. In the second base layer 2, the mass percentage of the main solid phase is greater than the sum of the mass percentages of the plurality of dispersed solid phases.

[0077] In some embodiments, the first base layer 1 material includes at least one of modified or unmodified polyethylene terephthalate, modified or unmodified polyethylene naphthalate, modified or unmodified polycarbonate, modified or unmodified polymethyl methacrylate, etc.

[0078] In some embodiments, the material of each second solid phase 2a is independently modified or unmodified from at least one of a polyester material, a modified or unmodified polyolefin, a modified or unmodified cellulose, and a modified or unmodified polymethyl methacrylate; the modified or unmodified polyester material includes at least one of a modified or unmodified polyethylene terephthalate, a modified or unmodified polyethylene naphthalate, and a modified or unmodified polycarbonate; the modified or unmodified polyolefin includes at least one of a modified or unmodified cyclic olefin copolymer; and the modified or unmodified cellulose includes modified or unmodified cellulose triacetate.

[0079] In one specific embodiment, the material of the dispersed solid phase is selected from at least one of modified or unmodified polymethyl methacrylate, modified or unmodified polyester (such as modified or unmodified polycarbonate), modified or unmodified polyolefin, and modified or unmodified cellulose, which are different from the host solid phase.

[0080] In some embodiments, in the second base layer 2, the mass percentage of the bulk solid phase is 90% to 99.99%, and the mass percentage of the dispersed solid phase is 0.01% to 10%.

[0081] For example, in the second base layer 2, the mass percentage of the bulk solid phase is 90%, 91%, 92%, 93%, 94%, 95%, 96%, 98%, 98.5%, 98.9%, 99%, and 99.99%; the mass percentage of the dispersed solid phase is 0.01%, 1%, 1.1%, 1.5%, 2%, 4%, 5%, 6%, 7%, 8%, 9%, and 10%.

[0082] In some embodiments, in the second base layer 2, the mass percentage of the bulk solid phase is 90% to 99.99%, and the mass percentage of the dispersed solid phase is 0.01% to 10%.

[0083] In some embodiments, in at least two different second solid phases 2a, at least one of the second solid phases 2a is made of the same material as the first solid phase 1c; that is, at least one second solid phase 2a has the same refractive index as the first solid phase 1c.

[0084] In this embodiment, when the solid material formed by the second base layer 2 is the same as the material of the first solid phase 1c, the interface 2b between the first base layer 1 and the second base layer 2 is not likely to appear, thus ensuring a certain mechanical stability, such as not being easily torn. At the same time, when the first base layer 1 and the second base layer 2 contain the same material, optical loss will be further reduced, ensuring overall light transmittance.

[0085] See Figures 3-4In some embodiments, the optical film 10 further includes an adhesive layer 4 located on the side of the first base layer 1 away from the second base layer 2, and / or, the adhesive layer 4 is located on the side of the second base layer 2 away from the first base layer 1.

[0086] The optical film 10 also includes at least one first particle 5, which is dispersed in the second base layer 2, and / or, at least one first particle 5 is dispersed in the first base layer 1, and / or, at least one first particle 5 is dispersed in the adhesive layer 4.

[0087] In some embodiments, there are two second base layers 2, respectively disposed on the first side 1a and the second side 1b, and the adhesive layer 4 is located on the side of the second base layer 2 away from the first base layer 1.

[0088] In some embodiments, the second base layer 2 is one, disposed on the first side 1a of the first base layer 1, and an adhesive layer 4 is located on the side of the second base layer 2 away from the first base layer 1, and an adhesive layer 4 is located on the side of the first base layer 1 away from the second base layer 2.

[0089] In some embodiments, the material of the first particle 5 is selected from at least one of calcium carbonate, barium sulfate, silicon dioxide, organosilicon, and barium dioxide.

[0090] In this embodiment of the application, by adding the first microparticle 5 to the second base layer 2, the light diffusion effect can be further enhanced, thereby further improving the anti-glare function of the optical film 10.

[0091] In some embodiments, the mass ratio of at least one first particle 5 to the second base layer 2 is greater than 0 and less than 2%; and / or, the mass ratio of at least one first particle 5 to the adhesive layer 4 is greater than 0 and less than 2%; and / or, the mass ratio of at least one first particle 5 to the first base layer 1 is greater than 0 and less than 2%.

[0092] For example, the mass ratio of at least one first particle 5 to the second base layer 2 is 0.1%, 0.2%, 0.5%, 0.7%, 1%, 1.2%, 1.5%, 1.7%, or 2%; the mass ratio of at least one first particle 5 to the first base layer 1 is 0.1%, 0.2%, 0.5%, 0.7%, 1%, 1.2%, 1.5%, 1.7%, or 2%; and the mass ratio of at least one first particle 5 to the adhesive layer 4 is 0.1%, 0.2%, 0.5%, 0.7%, 1%, 1.2%, 1.5%, 1.7%, or 2%.

[0093] In some embodiments, in the second base layer 2, the mass percentage of the main solid phase is 90% to 99.8%, the sum of the mass percentages of the multiple dispersed solid phases is 0.1% to 9.9%, and the mass percentage of the first particles is 0.1% to 0.15%. When the contents are as described above, the performance of the polarizer is further improved when the optical film is applied to the protective substrate of the polarizer.

[0094] See Figure 2 In some embodiments, the optical film 10 further includes a third base layer 3, the second base layer 2 is located on the first side 1a of the first base layer 1, the third base layer 3 is located on the second side 1b, and the third base layer 3 includes a substrate 301 and second particles 302 dispersed in the substrate 301.

[0095] In some embodiments, the second micrometer is an opening agent particle, which is a functional microparticle added to the thin film layer of the polarizer 100, having an anti-adhesion additive, used to solve the problem of interlayer adhesion caused by surface tension during film production or subsequent processing.

[0096] The material of the second particle 302 includes at least one of silicon dioxide (SiO2), talc, and calcium carbonate.

[0097] In some embodiments, the thickness of the first base layer 1 accounts for 60% to 99% of the thickness of the optical film 10, and the thickness of the second base layer 2 accounts for 1% to 40% of the thickness of the optical film 10.

[0098] It is understood that, in the embodiments of this application, when the second base layer 2 is respectively disposed on the first side 1a and the second side 1b of the first base layer 1, the ratio of the thickness of the second base layer 2 to the thickness of the optical film 10 is the ratio of the sum of the thicknesses of the two second base layers 2 to the thickness of the optical film 10.

[0099] For example, the thickness of the first base layer 1 accounts for 60%, 62%, 63%, 65%, 68%, 70%, 75%, 78%, 80%, 85%, 88%, 90%, 92%, 96%, and 99% of the thickness of the optical film 10; the thickness of the second base layer 2 accounts for 1%, 2%, 4%, 6%, 8%, 10%, 12%, 15%, 18%, 19%, 20%, 22%, 25%, 28%, 30%, 32%, 35%, 38%, and 40% of the thickness of the optical film 10.

[0100] In this embodiment of the application, by making the thickness of the first base layer 1 a large proportion of the thickness of the optical film 10, the optical film 10 can have a high transmittance and ensure a high mechanical strength.

[0101] In some embodiments, the thickness of the first base layer 1 accounts for 86.3% to 90% of the thickness of the optical film 10, and the thickness of the second base layer 2 accounts for 10% to 13.7% of the thickness of the optical film.

[0102] In this embodiment of the application, when the ratio of the thickness of the first base layer 1 to the thickness of the optical film 10 and the ratio of the thickness of the first base layer 1 to the thickness of the optical film 10 are adjusted to the above-mentioned values, the transmittance and mechanical strength of the optical film 10 can be further improved.

[0103] In some embodiments, the thickness of the optical film 10 is 10 micrometers to 100 micrometers.

[0104] For example, the thickness of the optical film 10 is 10μm, 12μm, 15μm, 18μm, 25μm, 35μm, 40μm, 50μm, 55μm, 60μm, 75μm, 90μm, or 100μm.

[0105] It is understood that the thickness in this embodiment is the thickness in the direction opposite to the first side 1a and the second side 1b.

[0106] In some embodiments, the thickness of the optical film is 38 micrometers to 60 micrometers.

[0107] In the embodiments of this application, when the thickness of the optical film is as described above, it has a high degree of polarization and transmittance when applied to the protective substrate of the polarizer.

[0108] In some embodiments, the first base layer 1 and the second base layer 2 are integrally formed.

[0109] In this application, the first base layer 1 and the second base layer 2 are integrally formed, that is, the first base layer 1 and the second base layer are connected to form a whole, and there is no interface between the first base layer 1 and the second base layer 2; that is, the optical film 10 is a single-layer structure as a whole, having a first base layer 1 part and a second base layer 2 part.

[0110] In some embodiments, the in-plane retardation value R0 of the optical film 10 is less than or equal to 3000 nm.

[0111] In some embodiments, the haze of the optical film 10 is 2.9% to 25%.

[0112] In some embodiments, the transmittance of the optical film 10 is greater than 90%.

[0113] The optical film 10 provided in this embodiment is prepared by a melt co-extrusion process, including the following steps:

[0114] Step S1: Provide raw materials for the first base layer 1 and the second base layer 2, wherein the raw materials for the second base layer 2 include at least two different materials that are mixed evenly;

[0115] Step S2: Melt the raw materials of the first base layer 1 and the second base layer 2 respectively;

[0116] Step S3: The raw materials after melting the first base layer 1 and the raw materials after melting the second base layer 2 are transported to the co-extrusion die head, and the layered composite is completed in the flow channel of the die head to form a continuous multilayer melt film;

[0117] Step S4: After cooling and shaping, an optical film is obtained.

[0118] Because the second base layer 2 was prepared using a melting process, different raw materials were mixed in the liquid phase, and after subsequent cooling and shaping, interface 2b was formed.

[0119] See Figures 5-6 This application embodiment also provides a polarizer 100, which includes a polarizing layer 15 and a protective substrate stacked with the polarizing layer 15. The protective substrate is the aforementioned optical film 10, and a first base layer 1 is located between the polarizing layer 15 and a second base layer 2.

[0120] In some embodiments, the optical film 10 includes two second base layers 2, one of which is located between the polarizing layer 15 and the first base layer 1, and the other is located on the side of the first base layer 1 away from the polarizing layer 5 (i.e., the first base layer 1 is located between the polarizing layer 5 and the second base layer 2).

[0121] In some embodiments, the optical film 10 includes a second base layer 2, a first base layer 1, and a third base layer 3. The second base layer 2 is located on one side of the first base layer 1, the third base layer 3 is located on the side of the first base layer 1 away from the second base layer 2, the third base layer 3 is located between the first base layer 1 and the polarizing layer 15, and the first base layer 1 is located between the polarizing layer 15 and the second base layer 2.

[0122] In some embodiments, the polarizing layer 15 comprises a substrate 301 film and a dichroic dye dispersed in the substrate 301 film.

[0123] It is understood that in the embodiments of this application, the dichroic dye can be inorganic, such as iodine / potassium iodide (I2 / KI), or organic, such as anthraquinone dyes, azo dyes and triphenyldiazepine and derivative dyes, monomethanone and polymethanone dyes, heterocyclic dyes, etc., or a mixture thereof.

[0124] In some embodiments, the material of the substrate 301 film includes a polyvinyl alcohol film.

[0125] In some embodiments, the substrate 301 film is stretched and oriented.

[0126] In some embodiments, the polarizer 100 further includes at least one of a compensation film 13 and an anti-reflection layer 17;

[0127] The compensation film 13 is located on the side of the polarizing layer 15 away from the protective substrate; the anti-reflection layer 17 is located on the side of the protective substrate away from the polarizing layer 15.

[0128] In some embodiments, the polarizer 100 further includes at least one of pressure-sensitive adhesive layer 12, adhesive layer, and surface protective film 18.

[0129] It is understood that the adhesive layer of the polarizer 100 in the embodiments of this application may be one or more.

[0130] In some embodiments, the material of the compensation membrane 13 includes at least one of cellulose triacetate, polyethylene terephthalate, polycarbonate, polymethyl methacrylate, polycyclic olefin, and polyethylene naphthalate.

[0131] In some embodiments, the polarizer 100 further includes a release film 11, which is disposed on the side of the pressure-sensitive adhesive layer 12 away from the compensation film 13.

[0132] In some embodiments, the in-plane retardation value (Re) of the compensation film 13 layers is 0 nm to 500 nm; the thickness direction retardation value (Rth) is 0 nm to 500 nm.

[0133] For example, the in-plane retardation value (Re) of the 13-layer compensation film can be 1nm, 50nm, 80nm, 100nm, 120nm, 150nm, 180nm, 200nm, 250nm, 300nm, 400nm, 450nm, or 500nm.

[0134] In some embodiments, the polarization degree of the polarizer 100 is greater than or equal to 99%.

[0135] For example, the polarizer 100 has polarization degrees of 99%, 99.1%, 99.2%, 99.3%, 99.5%, 99.9%, 99.99%, 99.993%, 99.994%, and 99.995%.

[0136] See Figure 5 In some embodiments, the polarizer 100 includes a release film 11, a pressure-sensitive adhesive layer 12, a compensation film 13, a first adhesive layer 14, a polarizing layer 15, a second adhesive layer 16, a protective substrate 10, and a surface protective film 18, which are stacked sequentially.

[0137] See Figure 6 In some embodiments, the polarizer 100 includes a release film 11, a pressure-sensitive adhesive layer 12, a compensation film 13, a first adhesive layer 14, a polarizing layer 15, a second adhesive layer 16, a protective substrate 10, an anti-reflective layer 17, and a surface protective film 18, which are stacked sequentially.

[0138] In some embodiments, the transmittance of the polarizer 100 is greater than or equal to 40%.

[0139] For example, the transmittance of polarizer 100 is 40%, 42.2%, 42.5%, 42.7%, and 42.9%.

[0140] See Figure 7 A third aspect of this application also provides a display device 200, which includes:

[0141] Display panel 20, the display panel 20 includes a light-incident side 20a and a light-emitting side 20b disposed opposite to each other; and

[0142] A polarizer 100 is located on the light-incident side 20a and / or the light-outceasing side 20b. The polarizer 100 is the aforementioned polarizer 100, and the polarizing layer 15 is located between the display panel 20 and the protective substrate 10.

[0143] In some embodiments, the display device 200 is a liquid crystal display device 200, including a lower polarizer 100b located on the light-incident side 20a of the display panel 20 and an upper polarizer 100a located on the light-emitting side 20b of the display panel 20, wherein the upper polarizer 100a and / or the lower polarizer 100b are selected from the polarizer 100 of the aforementioned embodiments.

[0144] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Specific Implementation

[0146] Example 1

[0147] See Figure 1 This embodiment provides an optical film 10, including two second base layers 2 and a first base layer 1. The first base layer 1 includes a first side 1a and a second side 1b disposed opposite to each other. The two second base layers 2 are respectively disposed on the first side 1a and the second side 1b, and the first base layer 1 and the two second base layers 2 are integrally formed. The material of the first base layer 1 is PET (polyethylene terephthalate) (Yizheng Chemical Fiber FG600), and the first base layer 1 has a first solid phase 1c formed from PET.

[0148] The second base layer 2 has multiple second solid phases 2a, and first particles 5 are dispersed in the second base layer 2. The material of the first particles 5 includes SiO2. The multiple second solid phases 2a include a main solid phase and multiple dispersed solid phases. The multiple dispersed solid phases are dispersed at different positions in the main solid phase, and each dispersed solid phase forms an interface 2b with the main solid phase.

[0149] The main solid phase is made of PET (Yizheng Chemical Fiber FG600), and the dispersed solid phase is made of PC (polycarbonate) (Teijin AD-5503LS2). In the second base layer 2, the mass percentage of the main solid phase is 98.9%, the mass percentage of the dispersed solid phase is 1%, the mass ratio of the first particles 5 is 0.1%, the thickness of the first base layer 1 is 35.2 μm, and the thickness of the two second base layers 2 is 2.4 μm.

[0150] Example 2

[0151] This embodiment provides an optical film whose structure and material content are the same as in Embodiment 1, except that the material of the dispersed solid phase is PMMA (Mitsubishi VH-067A).

[0152] Example 3

[0153] This embodiment provides an optical film whose structure and material types are the same as in Embodiment 1. The difference is that in the second base layer 2, the mass percentage of the main solid phase is 98.35%, the sum of the mass percentages of the multiple dispersed solid phases is 1.5%, the mass percentage of the first particle SiO2 is 0.15%, the thickness of the first base layer 1 is 32.8 μm, and the thickness of the two second base layers is 2.6 μm.

[0154] Example 4

[0155] This embodiment provides an optical film whose structure and material type are the same as in Embodiment 1. The difference in the second base layer 2 is that the mass percentage of the main solid phase is 90%, the sum of the mass percentages of the multiple dispersed solid phases is 9.9%, the mass ratio of the first particle SiO2 is 0.1%, the thickness of the first base layer 1 is 26 μm, and the thickness of the two second base layers is 2 μm.

[0156] Example 5

[0157] This embodiment provides an optical film whose structure and material type are the same as in Embodiment 1. The difference in the second base layer 2 is that the mass percentage of the main solid phase is 99.8%, the sum of the mass percentages of the multiple dispersed solid phases is 0.1%, the mass ratio of the first particle SiO2 is 0.1%, the thickness of the first base layer 1 is 52.8 μm, and the thickness of the two second base layers is 3.6 μm.

[0158] Example 6

[0159] This embodiment provides an optical film whose structure and material content are the same as in Embodiment 1. The difference is that the material of the first layer and the main solid phase is polyethylene naphthalate (PEN) (Teijin TN-8050SC, Japan), and the material of the multiple dispersed solid phases is cyclic olefin polymer (COP) (Zeonex 480R, Japan).

[0160] Example 7

[0161] This embodiment provides an optical film whose structure and material content are the same as those in Embodiment 3. The difference is that the material of the first layer and the main solid phase is PEN (Teijin TN-8050SC from Japan), and the material of the multiple dispersed solid phases is COP (Zeon K26R from Japan).

[0162] Example 8

[0163] This embodiment provides an optical film whose structure and material content are the same as in Embodiment 1. The difference is that the material of the first layer is PET (Yizheng Chemical Fiber FG600), the material of the main solid phase of the second layer is PC (Teijin AD-5503LS2), and the material of the dispersed solid phase is COP (Zeonex 480R). The absolute value of the difference in refractive index between the material of the first layer and the material of the main solid phase is less than or equal to 0.2.

[0164] It is understood that the optical films in Examples 1 to 8 were prepared using a three-layer melt co-extrusion process.

[0165] Comparative Example 1

[0166] This comparative example provides an optical film whose structure and materials are the same as in Example 2, except that the first base layer has a non-uniform solid phase generated from two materials, and the materials of the first base layer include 99% PET and 1% PMMA by mass.

[0167] The performance test results of the optical films of Examples 1-8 and Comparative Example 1 are shown in Table 1.

[0168] Table 1

[0169]

[0170]

[0171] It is understandable that the haze test in Table 1 is conducted according to GB / T 2410-2008.

[0172] Tensile strength MD and tensile strength TD refer to the tensile strength in the longitudinal and transverse directions within the surface of the optical film, respectively, with the transverse and longitudinal directions being perpendicular to each other.

[0173] As can be seen from the results in Table 1, compared with Comparative Example 1, Examples 1-8 have only one type of material in the first base layer, thus having only the first solid phase. The optical films in Examples 1-8 have a transmittance of over 90% while exhibiting haze, while the optical film in Comparative Example 1 has a transmittance of 85.1%, which is lower. Moreover, compared with Comparative Example 1, Examples 1-8 have a tensile strength MD of 230 MPa or higher and a tensile strength TD of 220 MPa or higher, both of which are superior to the mechanical strength of Comparative Example 1.

[0174] Application Examples

[0175] Application Example 1

[0176] See Figure 5 This application embodiment provides a polarizer 100, which includes a release film 11, a pressure-sensitive adhesive layer 12, a compensation film 13, a first adhesive layer 14, a polarizing layer 15, a second adhesive layer 16, a protective substrate, and a surface protective film 18 stacked in sequence. The protective substrate is the optical film 10 of Embodiment 1.

[0177] Application Example 2

[0178] This application embodiment provides a polarizer, the structure of which is the same as that of application embodiment 1, except that the protective substrate is the optical film of embodiment 2.

[0179] Application Example 3

[0180] See Figure 6 This application embodiment provides a polarizer, the structure of which is the same as that in application embodiment 1. The difference is that the protective substrate is the optical film of embodiment 2, and an anti-reflection layer is provided between the protective substrate and the surface protective film.

[0181] Application Examples 4-9

[0182] Application Examples 4 to 9 each provide a polarizer, the structure of which is the same as that of Application Example 1. The difference is that the protective substrate of the polarizer in Application Example 4 is the optical film of Example 3, the protective substrate of the polarizer in Application Example 5 is the optical film of Example 4, the protective substrate of the polarizer in Application Example 6 is the optical film of Example 5, the protective substrate of the polarizer in Application Example 7 is the optical film of Example 6, the protective substrate of the polarizer in Application Example 8 is the optical film of Example 7, and the protective substrate of the polarizer in Application Example 9 is the optical film of Example 8.

[0183] This application also provides polarizers for comparative application examples 1 to 3.

[0184] The structure and materials of the polarizer in Comparative Application Example 1 are the same as those in Application Example 1. The difference is that the protective substrate of the polarizer in Comparative Application Example 1 is made of only PET, and the surface of the protective substrate away from the polarizing layer is coated with an anti-glare coating AG3. The thickness of the protective substrate is 80 μm.

[0185] The structure and materials of the polarizer in Comparative Application Example 2 are the same as those in Application Example 2. The difference is that the protective substrate of the polarizer in Comparative Application Example 2 is made of only PET, and the surface of the protective substrate away from the polarizing layer is coated with an anti-glare coating AG25. The thickness of the protective substrate is 80 μm.

[0186] The structure and materials of the polarizer in Comparative Application Example 3 are the same as those in Application Example 3. The difference is that the protective substrate of the polarizer in Comparative Application Example 3 is made of only PET, and an anti-glare coating AG25 is provided between the protective substrate and the anti-reflective layer. The thickness of the protective substrate is 80 μm.

[0187] In comparison application example 1, AG3 represents an anti-glare coating with a haze of 3%;

[0188] In comparison application examples 2 and 3, AG25 represents an anti-glare coating with a haze of 25%.

[0189] The performance test results of the optical films in Application Examples 1 to 9 and Comparative Application Examples 1 to 3 are shown in Table 2.

[0190] Table 2

[0191]

[0192] Understandably, the polarizer performance in Table 2 was tested using the GB / T 35632-2017 method.

[0193] As shown in Table 2, the polarizers in Application Examples 1-9 use a protective substrate with anti-glare function, while the polarizers in Comparative Application Examples 1-3 use an anti-glare coating added to the surface of the protective substrate. It can be seen that, compared to Comparative Application Examples 1-3, Application Examples 1-9, without adding an additional anti-glare coating, not only replace the functions of existing polarizers but also integrate the anti-glare function, thereby reducing costs. Furthermore, since the anti-glare effect is achieved without adding an additional anti-glare coating, the transmittance of the polarizer is improved compared to Comparative Application Examples 1-3. Therefore, when the optical films in the embodiments of this application are applied to the protective substrate of polarizer films, they not only have an anti-glare function but also help reduce the overall thickness of the polarizer and improve transmittance; at the same time, by integrating the anti-glare function on the protective substrate without adding an additional anti-glare coating, the manufacturing cost of the polarizer is reduced.

[0194] The foregoing has provided a detailed description of an optical film, polarizer, and display device provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An optical film, characterized in that, The optical film includes: First-level grassroots; as well as, The second base layer is located on at least one side of the first base layer; Wherein, the first base layer has a first solid phase; The second base layer has at least two different second solid phases; in the at least two different second solid phases, at least some of the adjacent second solid phases are in contact to form a plurality of interfaces, the plurality of interfaces being distributed in the second base layer, and the materials of the adjacent second solid phases forming the interfaces are different; Of the plurality of interfaces, at least a portion of the interfaces are formed by the fusion of adjacent second solid phases at their junctions.

2. The optical film according to claim 1, characterized in that, The material of the second solid phase forming the interface includes a resin.

3. The optical film according to claim 1, characterized in that, In the at least two different second solid phases, the absolute value of the refractive index difference between at least one second solid phase and the first solid phase is less than or equal to 0.

2.

4. The optical film according to claim 1, characterized in that, In the at least two different second solid phases, at least one of the second solid phases is made of the same material as the first solid phase.

5. The optical film according to claim 1, characterized in that, The first base material comprises at least one of modified or unmodified polyethylene terephthalate, modified or unmodified polyethylene naphthalate, modified or unmodified polycarbonate, and modified or unmodified polymethyl methacrylate; and / or, The material of each of the second solid phases is independently selected from at least one of modified or unmodified polyester materials, modified or unmodified polyolefins, modified or unmodified cellulose, and modified or unmodified polymethyl methacrylate; The modified or unmodified polyester material includes at least one of modified or unmodified polyethylene terephthalate, modified or unmodified polyethylene naphthalate, and modified or unmodified polycarbonate. The modified or unmodified polyolefin includes at least one of modified or unmodified cyclic olefin copolymers; The modified or unmodified cellulose includes modified or unmodified cellulose triacetate.

6. The optical film according to claim 3, characterized in that, The at least two different second solid phases include a main solid phase and a plurality of dispersed solid phases; and the second solid phase with an absolute value of the refractive index difference from the first solid phase being less than or equal to 0.2 is the main solid phase, and the second solid phase with an absolute value of the refractive index difference from the first solid phase being greater than 0.2 is the dispersed solid phase. The plurality of dispersed solid phases are dispersed at different positions of the bulk solid phase, and each dispersed solid phase is in contact with the bulk solid phase to form the interface; In the second base layer, the mass percentage of the main solid phase is greater than the sum of the mass percentages of the plurality of dispersed solid phases.

7. The optical film according to claim 6, characterized in that, In the second base layer, the mass percentage of the main solid phase is 90% to 99.99%, and the sum of the mass percentages of the plurality of dispersed solid phases is 0.01% to 10%.

8. The optical film according to claim 1, characterized in that, The optical film further includes an adhesive layer, the adhesive layer being located on the side of the first base layer away from the second base layer, and / or, the adhesive layer being located on the side of the second base layer away from the first base layer; The optical film further includes at least one first microparticle; The at least one first particle is dispersed in the second base layer, and / or, the at least one first particle is dispersed in the first base layer, and / or, the at least one first particle is dispersed in the adhesive layer.

9. The optical film according to claim 8, characterized in that, The material of the first particle is selected from at least one of calcium carbonate, barium sulfate, silicon dioxide, organosilicon, and barium dioxide.

10. The optical film according to claim 8, characterized in that, The mass ratio of the at least one first particle to the second base layer is greater than 0 and less than 2%, and / or the mass ratio of the at least one first particle to the adhesive layer is greater than 0 and less than 2%, and / or the mass ratio of the at least one first particle to the first base layer is greater than 0 and less than 2%.

11. The optical film according to claim 1, characterized in that, The optical film also includes a third base layer; The third base layer is located on the side of the first base layer away from the second base layer, and the third base layer includes a substrate and second particles dispersed in the substrate.

12. The optical film according to claim 1, characterized in that, The thickness of the first base layer accounts for 60% to 99% of the thickness of the optical film, and the thickness of the second base layer accounts for 1% to 40% of the thickness of the optical film.

13. The optical film according to claim 11, characterized in that, The thickness of the optical film is 10 micrometers to 100 micrometers.

14. The optical film according to claim 1, characterized in that, The first base layer and the second base layer are integrally formed.

15. The optical film according to any one of claims 1 to 14, characterized in that, The in-plane retardation value R0 of the optical film is less than or equal to 3000 nm.

16. A polarizer, characterized in that, The polarizer includes a polarizing layer and a protective substrate stacked thereon, wherein the protective substrate is an optical film as described in any one of claims 1 to 15, and the first substrate is located between the polarizing layer and a second substrate.

17. The polarizer according to claim 16, characterized in that, The polarizer further includes a compensation film; the compensation film is located on the side of the polarizing layer away from the protective substrate; and / or, The polarizer also includes an anti-reflective layer, which is located on the side of the protective substrate away from the polarizing layer.

18. The polarizer according to claim 16, characterized in that, The polarization degree of the polarizer is greater than or equal to 99%; and / or, The transmittance of the polarizer is greater than or equal to 40%.

19. A display device, characterized in that, The display device includes: A display panel, comprising an incident light side and an emitted light side disposed opposite to each other; and... A polarizer, wherein the polarizer is located on the light-incident side and / or the light-outceasing side, the polarizer being the polarizer as described in any one of claims 16 to 18, and the polarizing layer being located between the display panel and the protective substrate.