Optical laminate

Abstract

The present application relates to an optical laminate or a reddening-resistant layer. The present application can provide an optical laminate or a reddening-resistant layer applied thereto that does not induce the so-called reddening phenomenon even when driven or maintained under very severe conditions (e.g., very high-temperature conditions).

Description

Technical Field

[0001] This application claims priority based on Korean Patent Application No. 10-2019-0037446, filed on March 29, 2019, and the content disclosed in the Korean patent application document is included as part of this specification.

[0002] This application relates to an optical laminate or an anti-reddening layer.

Background Art

[0003] The cases where display devices are driven and / or maintained under more severe conditions are increasing. For example, display devices used in vehicle displays such as navigation and vehicle instrument panels are maintained and / or driven at very high temperatures in summer.

[0004] Depending on the use of the display device, an optical laminate such as a polarizing plate can be used in contact with a glass substrate called a cover glass. Cover glass, etc. usually have better heat conduction characteristics than optical laminates. Therefore, heat is transmitted better to the optical laminate in contact with the cover glass.

[0005] Accordingly, it is required that the durability of an optical laminate such as a polarizing plate be maintained under particularly severe conditions (especially conditions maintained at a significantly higher temperature than in the past).

Summary of the Invention

Problems to be Solved by the Invention

[0006] This application provides an anti-reddening layer, an optical laminate, and a display device.

Means for Solving the Problems

[0007] Among the physical properties mentioned in this specification, the physical properties affected by the measurement temperature and / or measurement pressure in the results are the results measured at normal temperature and / or normal pressure unless otherwise specified.

[0008] The term "room temperature" refers to the natural temperature without heating or cooling, and for example, any one temperature within the range of 10°C to 30°C, a temperature of about 23°C or about 25°C. In this specification, the unit of temperature is °C unless otherwise specified separately.

[0009] The term "atmospheric pressure" refers to the natural pressure without pressurization or depressurization, and usually means about 1 atmosphere at the atmospheric pressure level.

[0010] In this specification, for physical properties where the measured humidity affects the results, unless otherwise specified separately, the physical properties are those measured at the natural humidity without separate adjustment under the above room temperature and atmospheric pressure conditions.

[0011] This application relates to an optical laminate, a display device, or a red-shading prevention layer. The optical laminate or display device may include the red-shading prevention layer. In this application, the term "red-shading prevention layer" is applied to various optical laminates including optical functional layers, and can mean all types of layers that can prevent, mitigate, reduce, suppress, and / or delay the red-shading of the optical laminate or the optical functional layer applied to the optical laminate. In particular, the red-shading prevention layer can effectively prevent, mitigate, reduce, suppress, and / or delay the red-shading of the optical functional layer even when a very heat-sensitive optical functional layer such as a polarizing layer (especially an iodine-based polarizing layer) described later is used and maintained under very harsh conditions such as a very high temperature.

[0012] The above-mentioned red-shading means the phenomenon that the optical laminate or the optical functional layer changes to red. The presence or absence of red-shading can be confirmed, for example, through the a value in the so-called CIE L * a * b * color space. An increase in the a value in the CIE L * a * a * b * color space in the positive direction means that the object has a greater red color. Also, an increase in the a * value in the positive direction means that the object has a greater red color. Also, the a* The larger the absolute value of the value in the negative direction, the more the object takes on a greenish color. Therefore, for the a of the optical functional layer or the optical laminate * change in value of * being larger in the positive direction compared to the initial a

[0013] In the present application, the term "reddening-resistant layer" can mean any type of layer that can be applied to an optical laminate or applied together with an optical functional layer to prevent, mitigate, reduce, suppress, and / or delay the change or increase in the positive direction of the a * value of the optical laminate and / or the optical functional layer.

[0014] The reddening mainly occurs easily when heat is applied to the optical laminate and / or the optical functional layer. Therefore, the higher the temperature at which the optical laminate and / or the optical functional layer is maintained, the easier the reddening occurs.

[0015] In the present application, the term "reddening-resistant layer" can refer to a layer that can make the absolute value of the change amount of the a * of the optical laminate or the optical functional layer 2 or less after a heat resistance test. The heat resistance test means a test of maintaining the optical laminate and / or the optical functional layer at about 95 °C for about 750 hours or at about 105 °C for about 250 hours. The * change amount of the a * value * a after the heat resistance test minus the * value (initial * value) * i is the numerical value obtained by subtracting, or conversely, the initial * a -a * i value (the * a * i ) minus the * value * a after the heat resistance test.* i -a * a It can be. In light of the purpose of the anti-reddening layer, the amount of change in the value of the aforesaid a * is the value of a after the heat resistance test * value a * a subtracting the initial a * value a * i from it, and the resulting numerical value a * a -a * i It can be.

[0016] The heat resistance test may be a heat resistance test conducted under harsher conditions than a normal heat resistance test. For example, the heat resistance test may be a heat resistance test conducted with the upper and lower surfaces (e.g., the entire upper surface and the entire lower surface) of the optical laminate and / or the optical functional layer in contact with a glass substrate. Since a glass substrate is generally a material with good heat transfer compared to an optical laminate or an optical functional layer, when the heat resistance test is conducted with the glass substrate in contact, the influence of the applied heat on the optical laminate and / or the optical functional layer becomes greater. The type of glass substrate applied to the heat resistance test is not particularly limited, but in this specification, a soda-lime glass substrate with a thickness of approximately 1.1 mm is used as a reference. Although a glass substrate is generally known to have a thermal conductivity of about 0.6 W / mK to 1.38 W / mK, even when the heat resistance test is conducted with the optical laminate or the optical functional layer of the present application in contact with a glass substrate having such a high thermal conductivity, reddening can be prevented, alleviated, reduced, suppressed, and / or delayed. The numerical values of the heat resistance test-related color coordinates and / or transmittance referred to in this specification are based on those with a soda-lime glass of about 1.1 mm thickness applied, and in the heat resistance test, the contact may mean a state where the optical functional layer or the optical laminate including the same is in direct contact with the glass substrate (a soda-lime glass plate with a thickness of about 1.1 mm).

[0017] The optical laminate of the present application can include an optical functional layer and the anti-reddening layer formed on at least one surface of the optical functional layer. By including the anti-reddening layer in the optical laminate, reddening of the optical laminate or the optical functional layer can be prevented, alleviated, reduced, suppressed, and / or delayed.

[0018] For example, the optical laminate or the optical functional layer contained therein, after a heat resistance test, the CIE L according to the following formula 1 * a * b * color coordinate a of * the change amount △a of the value * can have an absolute value within 2. The color coordinates mentioned in the present application are the results measured using a JASCO V-7100 Spectrophotometer.

[0019] [Formula 1] △a * =a * a -a * i

[0020] In Formula 1, △a * is the change amount of the color coordinate a * , a * a is the color coordinate a value after the heat resistance test * , a * i is the color coordinate a value before the heat resistance test * (initial a * value).

[0021] The absolute value of the change amount △a * in other examples, can be within about 1.9, within about 1.8, within about 1.7, within about 1.6, within about 1.5, within about 1.4, within about 1.3, within about 1.2, within about 1.1, within about 1.0, within about 0.9, within about 0.8, within about 0.7, within about 0.6, within about 0.5, within about 0.4, within about 0.3, within about 0.2, or within about 0.1. The change amount △a *Since the lower the absolute value, the less red coloration occurs, there is no limit to its lower limit value. In one exemplary case, the change amount △a * The absolute value of can be 0 or more. In one exemplary case, the change amount △a * The absolute value of can be the change amount when the value of a * changes in the positive direction compared to the initial value.

[0022] As described above, the heat resistance test is a process of maintaining the optical laminate and / or the optical functional layer at about 95°C for about 750 hours or at about 105°C for about 250 hours. Such a heat resistance test can be performed with the upper and lower surfaces (upper and lower entire surfaces) of the optical laminate and / or the optical functional layer in contact with the glass substrate (a soda-lime glass plate with a thickness of about 1.1 mm). The contact can be direct contact. The change amount of such a * value can be measured in the manner described in the examples of this specification.

[0023] When red coloration occurs in the optical laminate and / or the optical functional layer, usually, a phenomenon of a decrease in transmittance appears. Since the optical laminate of the present application has excellent resistance to red coloration, there is no change or the change is minimized in the transmittance.

[0024] For example, the optical laminate or the optical functional layer may have an absolute value of the change amount △Ts of the transmittance (single transmittance when the optical laminate is a polarizing plate or the optical functional layer is a polarizing layer) according to the following formula 2 within 5 in the same heat resistance test as for confirming formula 1. The transmittance is the result of measurement using a JASCO V-7100 spectrophotometer for light in the visible light region, for example, light in the range of approximately 380 nm to 780 nm.

[0025] [Formula 2] △Ts = T a - T i

[0026] In Formula 2, △Ts is the amount of change in the transmittance (when the optical laminate is a polarizing plate or the optical functional layer is a polarizing layer, the single transmittance), and T a is the transmittance after the heat resistance test (when the optical laminate is a polarizing plate or the optical functional layer is a polarizing layer, the single transmittance) (the transmittance after the heat resistance durability test), and T i is the transmittance before the heat resistance test (when the optical laminate is a polarizing plate or the optical functional layer is a polarizing layer, the single transmittance).

[0027] In other examples, the absolute value of the amount of change △Ts may be about 4.9 or less, about 4.8 or less, about 4.7 or less, about 4.6 or less, about 4.5 or less, about 4.4 or less, about 4.3 or less, about 4.2 or less, about 4.1 or less, about 4 or less, about 3.9 or less, about 3.8 or less, about 3.7 or less, about 3.6 or less, about 3.5 or less, about 3.4 or less, about 3.3 or less, about 3.2 or less, about 3.1 or less, about 3 or less, about 2.9 or less, about 2.8 or less, about 2.7 or less, about 2.6 or less, about 2.5 or less, about 2.4 or less, about 2.3 or less, about 2.2 or less, about 2.1 or less, about 1.9 or less, about 1.8 or less, about 1.7 or less, about 1.6 or less, about 1.5 or less, about 1.4 or less, about 1.3 or less, about 1.2 or less, about 1.1 or less, about 1.0 or less, about 0.9 or less, about 0.8 or less, about 0.7 or less, about 0.6 or less, about 0.5 or less, about 0.4 or less, about 0.3 or less, about 0.2 or less, or about 0.1 or less. Since less change in the transmittance results in less red coloration, the lower limit of the absolute value of the amount of change △Ts is 0. In other examples, the absolute value of such an amount of change △Ts may be slightly more than 0.

[0028] The heat resistance test for measuring the amount of change in the transmittance can be performed under the same conditions as the heat resistance test for measuring the amount of change in the * a value. The transmittance can be measured by the method described in the examples of this specification.

[0029] The optical laminate includes an optical functional layer. The term "optical functional layer" refers to a layer that exhibits at least one optically intended function. Examples of the optically intended functions include generation, reflection, refraction, absorption, scattering, and / or phase retardation of polarized light such as linear polarization or circular polarization. In the optical field, layers having such functions are widely known, and examples of the optical functional layers applicable in the present application may include all types of layers that pose a problem of red discoloration among the known optical functional layers.

[0030] In one exemplary case, the optical functional layer can be a polarization layer or a retardation layer. In this specification, the case where the optical functional layer is a polarization layer will be described, but the type of the optical functional layer is not limited to the polarization layer. Also, when the optical functional layer is a polarization layer, the optical laminate can be a polarizing plate.

[0031] In this specification, the terms "polarization layer" and "polarizing plate" refer to different objects. The term "polarization layer" refers to, for example, a multilayer or a single layer exhibiting a polarization function alone, and a polarizing plate can refer to a laminate including the polarization layer and other elements having no polarization function. Examples of the other elements included together with the polarization layer as described above may include a protective film or a protective layer of the polarization layer, the anti-red discoloration layer, the retardation layer, the adhesive layer, the pressure-sensitive adhesive layer, the hard coat layer, or the low reflection layer, etc., but are not limited thereto.

[0032] The type of the polarizing layer applied in this application is not basically limited. The most common known polarizing layer is a linear absorption type polarizing layer, namely a so-called poly(vinyl alcohol) (hereinafter referred to as PVA) polarizing layer. In this specification, the term "PVA" means polyvinyl alcohol or its derivative unless otherwise specified. Examples of the PVA polarizing layer include a stretched PVA film in which an absorption anisotropic substance such as iodine or a dichroic dye is adsorbed and oriented, and a so-called coating type PVA polarizing layer formed by applying PVA in a coating method to form a thin polarizing layer. In this application, all types of polarizing layers as described above can be applied. In addition to the PVA polarizing layer, a polarizing plate formed of a liquid crystal compound such as LLC (Lyotropic Liquid Crystal), a polarizing layer formed by orienting a polymerizable liquid crystal compound (so-called RM (Reactive Mesogen)) and a dichroic dye in a GH (Guest-Host) method can also be applied in this application.

[0033] In this application, particularly when an iodine-based polarizing layer is applied as the polarizing layer, the reddening of the iodine-based polarizing layer can be effectively prevented, alleviated, reduced, suppressed and / or delayed.

[0034] The iodine-based polarizing layer is a polarizing layer in which an iodine-based substance is applied as the absorption anisotropic substance. As the absorption anisotropic substance, typically an iodine-based substance is applied, or a dichroic dye such as an azo dye may be applied. In the former case, it is called an iodine-based polarizing layer, and in the latter case, it may be called a dye-based polarizing layer. The iodine-based polarizing layer can generally exhibit superior optical performance (e.g., high transmittance, high degree of polarization, and high contrast) compared to the dye-based polarizing layer. However, the iodine-based polarizing layer has significantly lower heat resistance compared to the dye-based polarizing layer. In particular, the iodine-based substance contained in the iodine-based polarizing layer decomposes under high temperature and / or high humidity conditions, easily generating I2 substances, which induce reddening through inappropriate absorption in the visible light region. Therefore, in applications where durability under high temperature and / or high humidity conditions is essentially required, the dye-based polarizing layer may be applied even if there is a sacrifice in optical characteristics. However, according to the present application, even when an iodine-based polarizing layer is applied, and further, even when such an iodine-based polarizing layer is maintained and used under severe conditions such as significantly high temperature conditions, the reddening of the iodine-based polarizing layer can be effectively prevented, alleviated, reduced, suppressed, and / or delayed. Therefore, according to the present application, while solving the disadvantages of the iodine-based polarizing layer, its advantages can be taken.

[0035] The iodine-based polarizing layer can be an iodine-based PVA polarizing layer. The iodine-based PVA polarizing layer is a polarizing layer in which an iodine-based substance is oriented in the stretched PVA film or the coating-type PVA polarizing layer.

[0036] According to the present application, even when an iodine-based polarizing layer with weak durability as described above is applied, the reddening phenomenon can be effectively prevented while taking the advantages of the polarizing layer. However, the type of polarizing layer applied in the present application is not limited to the iodine-based polarizing layer.

[0037] The polarizing layer applied in the embodiments of the present application is an iodine-based PVA polarizing layer, and such a polarizing layer is usually manufactured by dyeing and stretching a PVA disk film. In the manufacturing process of the PVA polarizing layer, additional processes such as swelling, cross-linking, washing, and / or complementary color processes can optionally be carried out, and the process of manufacturing the PVA polarizing layer through such processes is known.

[0038] In one example, in order to ensure the durability of the optical laminate, particularly high-temperature reliability, an iodine-based PVA polarizing layer containing a zinc component can be used as the polarizing layer. Examples of the zinc component include zinc and / or zinc ions. The PVA polarizing layer can also contain a potassium component such as potassium or potassium ions as an additional component. Using a polarizing layer containing such components can provide an optical laminate that stably maintains durability even under high-temperature conditions.

[0039] The ratio of the potassium and / or zinc component can be additionally adjusted. For example, the ratio K / Zn of the potassium component K to the zinc component Zn contained in the PVA polarizing layer can be in the range of 0.2 to 8 in one example. The ratio K / Zn can be about 0.4 or more, 0.6 or more, 0.8 or more, 1 or more, 1.5 or more, 2 or more, or 2.5 or more, and can be 7.5 or less, 7 or less, 6.5 or less, 6 or less, 5.5 or less, about 5 or less, about 4.5 or less, or about 4 or less in other examples. The ratio can be a molar ratio or a weight ratio.

[0040] The content of the potassium component contained in the PVA polarizing layer can be about 0.1 to 2% by weight. In other examples, the ratio of the potassium component can be about 0.15% by weight or more, about 0.2% by weight or more, about 0.25% by weight or more, about 0.3% by weight or more, about 0.35% by weight or more, 0.4% by weight or more, or about 0.45% by weight or more, about 0.5% by weight or more, about 0.55% by weight or more, about 0.6% by weight or more, about 0.65% by weight or more, about 0.7% by weight or more, about 0.75% by weight or more or about 0.8% by weight or more, and can be about 1.95% by weight or less, about 1.9% by weight or less, about 1.85% by weight or less, about 1.8% by weight or less, about 1.75% by weight or less, about 1.7% by weight or less, about 1.65% by weight or less, about 1.6% by weight or less, about 1.55% by weight or less, about 1.5% by weight or less, about 1.45% by weight or less, about 1.4% by weight or less, about 1.35% by weight or less, about 1.3% by weight or less, about 1.25% by weight or less, about 1.2% by weight or less, about 1.15% by weight or less, about 1.1% by weight or less, about 1.05% by weight or less, about 1% by weight or less, about 0.95% by weight or less, about 0.9% by weight or less or about 0.85% by weight or less.

[0041] In one example, the ratio of the potassium component to the zinc component may be included so as to satisfy the following formula 3.

[0042] [Formula 3] 0.70~1=1 / (1+0.025d / R)

[0043] In formula 3, d is the thickness (μm) of the PVA polarizing layer, and R is the ratio K / Zn of the weight ratio K (unit: weight%) of the potassium component contained in the polarizing layer to the weight ratio Zn (unit: weight%) of the zinc component.

[0044] By including potassium and zinc components in the polarizing layer, a polarizing layer excellent in reliability at high temperatures can be provided.

[0045] In Equation 3, the value of 1 / (1 + 0.025d / R) may be, in other examples, about 0.75 or more, 0.8 or more, or 0.85 or more, and the value of 1 / (1 + 0.025d / R) may be about 0.97 or less, about 0.95 or less, or about 0.93 or less.

[0046] In the above-described content, the content of the potassium and / or zinc component can be measured in the manner described in the examples of this specification.

[0047] The polarizing layer applied in the examples of the present application can be a polarizing layer manufactured by a known method for manufacturing a polarizing layer. Further, when attempting to apply a polarizing layer containing the potassium and / or zinc component as the polarizing layer in the present application, the process conditions can be controlled during the manufacturing process of the known polarizing layer so that zinc and / or potassium can be included in the polarizing layer, and it can be manufactured.

[0048] As described above, the PVA polarizing layer is usually manufactured by dyeing and stretching a PVA film (disc film), and optionally, swelling, cross-linking, washing, and / or complementary color processes can be additionally performed during the manufacturing process of the PVA polarizing layer. The stretching process can be performed in a separate process or simultaneously with other processes such as the dyeing, swelling, and / or cross-linking processes. In such a manufacturing process, treatment liquids such as a dyeing liquid, a cross-linking liquid, a swelling liquid, a washing liquid, and / or a complementary color liquid are applied, and by adjusting the components of this treatment liquid, it is possible to determine the presence or absence of inclusion of the potassium and / or zinc component or adjust its ratio, etc.

[0049] In the dyeing process, an absorption anisotropic substance can be adsorbed and / or oriented on the PVA film. Such a dyeing process can be carried out together with a stretching process as required. Dyeing can be performed by immersing the film in a solution containing an absorption anisotropic substance, for example, an iodine solution. As the iodine solution, for example, an aqueous solution containing iodine ions with iodine I2 and an iodide compound as a dissolution aid can be used. As the iodide compound, for example, potassium iodide, lithium iodide, sodium iodide, zinc iodide, aluminum iodide, lead iodide, copper iodide, barium iodide, calcium iodide, tin iodide or titanium iodide can be used. The concentration of iodine and / or iodide ions in the iodine solution can be adjusted in consideration of the optical properties of the target polarizing layer, and such an adjustment method is known. Usually, the iodine content in the dyeing solution (iodine solution) is about 0.01 to 5% by weight, and the concentration of the iodide compound can be about 0.01 to 10% by weight. In other examples, the iodine content may be 0.05% by weight or more, 0.1% by weight or more, or 0.15% by weight or more, and may be about 4.5% by weight or less, 4% by weight or less, 3.5% by weight or less, 3% by weight or less, 2.5% by weight or less, 2% by weight or less, 1.5% by weight or less, 1% by weight or less, or 0.5% by weight or less. In other examples, the concentration of the iodide compound may also be 0.05% by weight or more, 0.1% by weight or more, 0.5% by weight or more, 1% by weight or more, 1.5% by weight or more, or 2% by weight or more, and may be about 9% by weight or less, 8% by weight or less, 7% by weight or less, 6% by weight or less, 5% by weight or less, 4% by weight or less, or 3% by weight or less. In the dyeing process, the temperature of the iodine solution is usually about 20°C to 50°C, 25°C to 40°C, and the immersion time is usually about 10 seconds to 300 seconds or 20 seconds to 240 seconds, but it is not limited thereto.

[0050] The stretching process is generally carried out by uniaxial stretching, but other stretching methods such as biaxial stretching can also be applied as necessary. Such stretching can also be carried out together with the above-mentioned dyeing and / or the cross-linking process described later. The stretching method is not particularly limited, and for example, a wet method can be applied. In such a wet method, for example, it is common to perform stretching after dyeing. Stretching can be carried out together with cross-linking and can also be carried out multiple times or in multiple stages. The above-mentioned iodide compound can be contained in the treatment liquid applied to the wet stretching method. The concentration of the iodide compound in the treatment liquid can be about 0.01 to 10% by weight. In other examples, the concentration of the iodide compound may also be 0.05% by weight or more, 0.1% by weight or more, 0.5% by weight or more, 1% by weight or more, 1.5% by weight or more, or 2% by weight or more, and may be about 9% by weight or less, 8% by weight or less, 7% by weight or less, 6% by weight or less, 5% by weight or less, 4% by weight or less, or 3.5% by weight or less. In stretching, the treatment temperature is usually within the range of 25°C or higher, 30°C to 85°C, or 40°C to 70°C, and the treatment time is usually 10 seconds to 800 seconds, or 30 seconds to 500 seconds, but it is not limited thereto. In the stretching process, the total stretching ratio can be adjusted in consideration of orientation characteristics, etc., and the total stretching ratio can be about 3 to 10 times, 4 to 8 times, or 5 to 7 times based on the original length of the PVA film, but it is not limited thereto. In the above, the total stretching ratio can mean the cumulative stretching ratio including the stretching in each process when stretching is also involved in other processes such as swelling, dyeing, and / or cross-linking processes other than the stretching process. Such a total stretching ratio can be adjusted within an appropriate range in consideration of orientation, processability of the polarizing layer, or stretch cutting possibility, etc.

[0051] In the manufacturing process of the polarizing layer, a swelling process can be further carried out in addition to the above-mentioned dyeing and stretching, and this is usually carried out before the dyeing process. Swelling can wash away contaminants on the surface of the PVA film and anti-blocking agents, and it also has the effect of reducing non-uniformities such as dyeing unevenness.

[0052] In the swelling process, usually, water, distilled water, pure water, etc. can be used. The main component of the treatment liquid is water, and if necessary, additives such as potassium iodide and other iodide compounds or surfactants, etc., or a small amount of alcohol, etc. may be contained. The treatment temperature in the swelling process is usually about 20°C to 45°C or 20°C to 40°C, but it is not limited to this. Since swelling unevenness can induce dyeing unevenness, the process variables can be adjusted so as to suppress the occurrence of such swelling unevenness as much as possible. In the swelling process, appropriate stretching can also be arbitrarily performed. The stretching ratio can be 6.5 times or less, 1.2 to 6.5 times, about 2 to 4 times, or about 2 to 3 times based on the original length of the PVA film. The stretching in the swelling process can control the stretching in the stretching process performed after the swelling process to be small, and can be controlled so that stretching breakage of the film does not occur.

[0053] The crosslinking process can be carried out using a crosslinking agent such as a boron compound. The order of the crosslinking process is not particularly limited, and for example, it can be carried out together with the dyeing and / or stretching process, or can proceed separately. The crosslinking process can also be carried out multiple times. As the boron compound, boric acid or borax, etc. can be used. The boron compound can generally be used in the form of an aqueous solution or a mixed solution of water and an organic solvent, and usually, an aqueous boric acid solution is used. The concentration of boric acid in the aqueous boric acid solution can be selected within an appropriate range considering the degree of crosslinking and the heat resistance, etc. caused thereby. An iodide compound such as potassium iodide can also be contained in the aqueous boric acid solution, etc. The concentration of the iodide compound in the aqueous boric acid solution can be about 0.01 to 10% by weight. In other examples, the concentration of the iodide compound may also be 0.05% by weight or more, 0.1% by weight or more, 0.5% by weight or more, 1% by weight or more, 1.5% by weight or more, or 2% by weight or more, and may be about 9% by weight or less, 8% by weight or less, 7% by weight or less, 6% by weight or less, 5% by weight or less, 4% by weight or less, or 3.5% by weight or less. The crosslinking process can be carried out by immersing the PVA film in an aqueous boric acid solution, etc. In this process, the treatment temperature is usually in the range of 25°C or higher, 30°C to 85°C or about 30°C to 60°C, and the treatment time is usually about 5 seconds to 800 seconds or about 8 seconds to 500 seconds.

[0054] In the manufacturing process of the polarizing layer, metal ion treatment can be performed, which can usually be called a complementary color process. Such treatment is carried out, for example, by immersing a PVA film in an aqueous solution containing a metal salt. Through this, metal components such as metal ions can be contained in the polarizing layer, and the type and ratio of the metal components can be adjusted in this process. Examples of metal ions that can be applied include metal ions of transition metals such as cobalt, nickel, zinc, chromium, aluminum, copper, manganese, or iron. By selecting an appropriate type among these, adjustment of the color tone may be possible.

[0055] To manufacture a polarizing layer containing zinc, a zinc component may be included in the treatment liquid (aqueous solution containing a metal salt) applied in the complementary color process. However, if necessary, the zinc component can also be applied during other processes. In such cases, the zinc component can also be included in other treatment liquids such as a dyeing liquid or a crosslinking liquid, or a separate treatment liquid. The zinc component can be introduced, for example, by dissolving one or more zinc salts selected from zinc chloride, zinc iodide, zinc sulfate, zinc nitrate, zinc acetate, etc. in the aqueous solution. In such a case, in order to achieve the target zinc content, the concentration of the zinc salt can be adjusted to about 0.01 to 10% by weight. The concentration of the zinc salt can also be, in other examples, 0.05% by weight or more, 0.1% by weight or more, 0.5% by weight or more, 1% by weight or more, 1.5% by weight or more, or 2% by weight or more, or about 9% by weight or less, 8% by weight or less, 7% by weight or less, 6% by weight or less, 5% by weight or less, 4% by weight or less, or 3% by weight or less. If necessary, a potassium component can also be included in the treatment liquid. Examples of the potassium component can include potassium salts such as potassium iodide. The concentration of the potassium salt can be about 0.01 to 10% by weight. The concentration can also be, in other examples, 0.05% by weight or more, 0.1% by weight or more, 0.5% by weight or more, 1% by weight or more, 1.5% by weight or more, 2% by weight or more, 2.5% by weight or more, 3% by weight or more, 3.5% by weight or more, 4% by weight or more, 4.5% by weight or more, or 5% by weight or more, or about 9% by weight or less, 8% by weight or less, 7% by weight or less, or 6% by weight or less. By applying zinc salts and potassium salts as described above in the complementary color process, the target levels of zinc and potassium components can be included in the polarizing layer.

[0056] During the manufacturing process of the polarizing layer, a washing process can be carried out after dyeing, crosslinking, and stretching. Such a washing process can usually be carried out before the complementary color process and can be carried out using water. If necessary, appropriate amounts of other components such as iodine, iodide, other metal salts, and components such as liquid alcohols such as methanol, ethanol, isopropyl alcohol, butanol, or propanol can also be blended in the water applied in the washing process.

[0057] After undergoing such a process, a drying process can be performed to manufacture the polarizing layer. In the drying process, for example, it can be carried out at an appropriate temperature for an appropriate time in consideration of, for example, the moisture content required for the polarizing layer, and such conditions are not particularly limited.

[0058] As described above in the foregoing process, a zinc and / or potassium component can be included in the polarizing layer. However, the method for manufacturing the polarizing layer containing the zinc and / or potassium component is not limited thereto. For example, a zinc salt can be included in a treatment liquid applied to swelling, dyeing, crosslinking, stretching, and / or washing processes, and the zinc component can be included in the polarizing layer in other processes instead of the complementary color process. Also, since a potassium component such as potassium iodide may be included in the treatment liquid applied to the swelling, dyeing, crosslinking, stretching, and / or washing processes, etc., the ratio of the potassium component can also be adjusted in this process. Those skilled in the art can appropriately adopt a general method for manufacturing a polarizing layer to include a desired level of zinc and / or potassium component in the polarizing layer according to the purpose.

[0059] The thickness of the polarizing layer is not limited. In the present application, a generally known polarizing layer can be applied, so its thickness also applies the normal thickness. Usually, the thickness of the polarizing layer can be within the range of 5 μm to 80 μm, but it is not limited thereto.

[0060] The optical laminate of the present application includes the anti-reddening layer.

[0061] The present application relates to an optical laminate or a display device including the anti-reddening layer, or relates to the anti-reddening layer.

[0062] As mentioned above, the term "reddening-resistant layer" is a layer that can prevent, mitigate, reduce, suppress, and / or delay the reddening of the optical laminate and / or the optical functional layer. The reddening of the optical laminate and / or the optical functional layer is expected to be caused by heat and / or moisture, or at least accelerated by heat and / or moisture. With the expansion of the applications of display devices, the optical laminate and / or the optical functional layer are more frequently exposed to higher temperatures, which has led to an increasing frequency of cases where optical functional layers and optical laminates that did not previously have a problem with reddening cause reddening in the new applications.

[0063] Therefore, as the reddening-resistant layer, a layer that serves to block the heat applied to the optical laminate and / or the optical functional layer, reduce the degree of the applied heat, or delay the heat transfer rate can be applied.

[0064] In one example, the anti-reddening layer is a void-containing layer (porous layer) (or a porous layer) described later, or a laminate including the void-containing layer (porous layer) (or a porous layer), and can be a layer that exists sufficiently adjacent to the optical functional layer. By making the anti-reddening layer a void-containing layer (porous layer) or a layer including the void-containing layer (porous layer), heat transfer can be effectively blocked. As described above, the optical functional layer can be a layer that causes reddening, such as the iodine-based polarizing layer described above. Also, the fact that the anti-reddening layer exists sufficiently adjacent to the optical functional layer means that the position of the anti-reddening layer and the distance between the anti-reddening layer and the optical functional layer are adjusted so that the anti-reddening layer can block the heat transfer to the optical functional layer at a level that can prevent, mitigate, reduce, suppress, and / or delay reddening. For example, even if there is a layer having a configuration similar to the anti-reddening layer of the present application described later, if such a layer does not exist at a position and distance where it can block the heat transfer to the optical functional layer, such a layer cannot be said to be the anti-reddening layer in the present application. For example, the so-called sufficiently adjacent may be the case where the distance between the optical functional layer that causes reddening and the anti-reddening layer is within about 90 μm, within about 85 μm, within about 80 μm, within about 75 μm, within about 70 μm, within about 65 μm, within about 60 μm, within about 55 μm, within about 50 μm, within about 45 μm, within about 40 μm, within about 35 μm, within about 30 μm, within about 25 μm, within about 20 μm, within about 15 μm, within about 10 μm, within about 5 μm, within about 1 μm, within about 0.9 μm, within about 0.8 μm, within about 0.7 μm, within about 0.6 μm, within about 0.5 μm, within about 0.4 μm, within about 0.3 μm, or within about 0.2 μm. Also, the sufficient adjacency includes the case where the optical functional layer and the anti-reddening layer are in contact with each other. In such a case, the distance is 0 μm. Therefore, the lower limit of the distance is 0 μm. In other examples, the distance may be about 0.01 μm or more, about 0.02 μm or more, about 0.03 μm or more, about 0.04 μm or more, about 0.05 μm or more, about 0.09 μm or more, or about 0.1 μm or more. As described above, the distance can be the shortest distance, the maximum distance, or the average distance between the opposing surfaces of the anti-reddening layer and the optical functional layer.

[0065] In one example, the anti-reddening layer is a void-containing layer (porous layer) (or a porous layer) described later, or a laminate including the void-containing layer (porous layer) (or a porous layer), and can be a layer having a sufficient thickness capable of preventing reddening of the optical functional layer. That is, even when the anti-reddening layer is a void-containing layer (porous layer) or a layer including the void-containing layer (porous layer), if an appropriate thickness is not ensured, heat transfer cannot be effectively blocked. For example, even if there is a layer having a configuration similar to the anti-reddening layer of the present application described later, if such a layer does not have a thickness sufficient to block heat transfer to the optical functional layer, such a layer cannot be said to be the anti-reddening layer in the present application. In one example, the sufficient thickness may be, for example, about 200 nm or more, about 250 nm or more, about 300 nm or more, about 350 nm or more, about 400 nm or more, about 450 nm or more, about 500 nm or more, about 550 nm or more, about 600 nm or more, about 650 nm or more, about 700 nm or more, about 750 nm or more, about 800 nm or more, about 850 nm or more, or about 900 nm or more. The upper limit of the thickness is not particularly limited. The thicker the anti-reddening layer, the more improved the effect of preventing, alleviating, reducing, suppressing, and / or delaying heat. Therefore, the upper limit of the thickness of the anti-reddening layer or the void-containing layer (porous layer) can be selected in consideration of the thickness required for the optical laminate as long as the heat prevention, alleviation, reduction, suppression, and / or delay effect is ensured, and there is no particular limitation. In one example, the thickness of the anti-reddening layer or the void-containing layer (porous layer) may be about 3,000 nm or less, about 2,900 nm or less, about 2,800 nm or less, about 2,700 nm or less, about 2,600 nm or less, about 2,500 nm or less, about 2,400 nm or less, about 2,300 nm or less, about 2,200 nm or less, about 2,100 nm or less, about 2,000 nm or less, or about 1,950 nm or less.

[0066] In one example, the anti-reddening layer can be a layer having a thermal diffusivity within a predetermined range. For example, the anti-reddening layer can be formed on a polymer film to produce a laminate, and the thermal diffusivity measured at 95 °C for the laminate can be at a level such that it is 90% or less compared to the thermal diffusivity of the polymer film alone.

[0067] In such a case, the anti-reddening layer can satisfy the following Equation 4.

[0068] In the present application, the term "anti-reddening layer" can refer to the void-containing layer (porous layer) itself or a laminate at least including the void-containing layer (porous layer). Therefore, the anti-reddening layer referred to in Equation 4 below can be a void-containing layer (porous layer) or a laminate including the same.

[0069] [Equation 4] H L ≦0.9 × H P

[0070] In Equation 4, H L is the thermal diffusivity of a laminate of the polymer film and the anti-reddening layer formed on one surface of the polymer film, and H P is the thermal diffusivity of the polymer film.

[0071] In the present specification, the type of the polymer film for measuring the thermal diffusivity is not particularly limited. For example, the polymer film in Equation 4 can be a TAC (Triacetyl cellulose) film with a thickness of about 60 μm. The thermal diffusivity (95 °C) of the laminate is, in other examples, the thermal diffusivity (95 °C) H of the TAC film Pabout 89% or less, about 88% or less, about 87% or less, about 86% or less, about 85% or less, about 84% or less, about 83% or less, about 82% or less, about 81% or less, about 80% or less, about 79% or less, about 78% or less, about 77% or less, about 76% or less, about 75% or less, about 74% or less, about 73% or less, about 72% or less, about 71% or less, about 70% or less, about 69% or less, about 68% or less, about 67% or less, about 66% or less, or about 65% or less, or about 10% or more, about 11% or more, about 12% or more, about 13% or more, about 14% or more, about 15% or more, about 16% or more, about 17% or more, about 18% or more, about 19% or more, about 20% or more, about 21% or more, about 22% or more, about 23% or more, about 24% or more, about 25% or more, about 26% or more, about 27% or more, about 28% or more, about 29% or more, about 30% or more, about 31% or more, about 32% or more, about 33% or more, about 34% or more, about 35% or more, about 36% or more, about 37% or more, about 38% or more, about 39% or more, about 40% or more, about 41% or more, about 42% or more, about 43% or more, about 44% or more, about 45% or more, about 46% or more, about 47% or more, about 48% or more, about 49% or more, about 50% or more, about 51% or more, about 52% or more, about 53% or more, about 54% or more, about 55% or more, about 56% or more, about 57% or more, about 58% or more, about 59% or more, or about 60% or more may be acceptable.

[0072] Therefore, in Equation 4, the H P multiplied by the coefficient can be 0.89, 0.88, 0.87, 0.86, 0.85, 0.84, 0.83, 0.82, 0.81, 0.80, 0.79, 0.78, 0.77, 0.76, 0.75, 0.74, 0.73, 0.72, 0.71, 0.70, 0.69, 0.68, 0.67, 0.66, or 0.65. Also, in Equation 4, H L is about 0.10 × H P or more, about 0.11 × H P or more, about 0.12 × H PAbove, approximately 0.13×H P Above, approximately 0.14×H P Above, approximately 0.15×H P Above, approximately 0.16×H P Above, approximately 0.17×H P Above, approximately 0.18×H P Above, approximately 0.19×H P Above, approximately 0.20×H P Above, approximately 0.21×H P Above, approximately 0.22×H P Above, approximately 0.23×H P Above, approximately 0.24×H P Above, approximately 0.25×H P Above, approximately 0.26×H P Above, approximately 0.27×H P Above, approximately 0.28×H P Above, approximately 0.29×H P Above, approximately 0.30×H P Above, approximately 0.31×H P Above, approximately 0.32×H P Above, approximately 0.33×H P Above, approximately 0.34×H P Above, approximately 0.35×H P Above, approximately 0.36×H P Above, approximately 0.37×H P Above, approximately 0.38×H P Above, approximately 0.39×H P Above, approximately 0.40×H P Above, approximately 0.41×H P Above, approximately 0.42×H P Above, approximately 0.43×H P Above, approximately 0.44×H P Above, approximately 0.45×H P Above, approximately 0.46×H P Above, approximately 0.47×H P Above, approximately 0.48×H P Above, approximately 0.49×H P Above, approximately 0.50×H P Above, approximately 0.51×H P Above, approximately 0.52×H P Above, approximately 0.53×H P Above, approximately 0.54×H P Above, approximately 0.55×H P Above, approximately 0.56×HP Above, approximately 0.57×H P Above, approximately 0.58×H P Above, approximately 0.59×H P Above or approximately 0.60×H P It may be above this value.

[0073] The surface properties of the anti-reddening layer or the void-containing layer (porous layer) can be controlled. Since the anti-reddening layer or the void-containing layer (porous layer) is located adjacent to the optical functional layer where reddening must be prevented, alleviated, reduced, suppressed, and / or delayed, it can be directly attached to the optical functional layer or attached to other layers of the optical laminate adjacent to the optical functional layer. In such a case, by controlling the surface properties of the anti-reddening layer or the void-containing layer (porous layer), the anti-reddening layer or the void-containing layer (porous layer) can adhere with excellent adhesion to the optical functional layer or other layers, thereby more effectively preventing, alleviating, reducing, suppressing, and / or delaying the reddening. For example, the anti-reddening layer or the void-containing layer (porous layer) can include at least one surface having a surface area ratio of about 0.02 or more as measured by an atomic force microscope (AFM). For example, at least one surface or both surfaces of the main surface of the anti-reddening layer or the void-containing layer (porous layer) can have the surface area ratio. In one exemplary case, the surface of the anti-reddening layer or the void-containing layer (porous layer) having at least the surface area ratio can be the surface facing the optical functional layer or other layers to which the anti-reddening layer or the void-containing layer (porous layer) is attached. In other exemplary cases, the surface area ratio of the anti-reddening layer or the void-containing layer (porous layer) can be about 0.022 or more, about 0.024 or more, about 0.026 or more, about 0.028 or more, about 0.03 or more, about 0.032 or more, or 0.034 or more, or can be about 0.5 or less, about 0.45 or less, about 0.4 or less, about 0.35 or less, about 0.3 or less, or about 0.25 or less. The surface area ratio can be measured by the method described in the examples.

[0074] The red heat resistant layer or void-containing layer (porous layer) can exhibit a desired level of reflectance with respect to infrared rays. Since heat is also transmitted in the form of infrared rays, appropriate reflectance with respect to this can ensure the desired red heat prevention characteristics. In this specification, the term "infrared rays" can mean electromagnetic waves having any one wavelength within the range of approximately 800 nm to 1,300 nm, or wavelengths within a partial region within the above range or wavelengths of the entire region. Therefore, the infrared reflectance can be the reflectance with respect to any one wavelength within the range of 800 nm to 1,300 nm, or the average reflectance with respect to a partial region or the entire region within the above range. The reflectance can be measured by the method described in the examples of this specification. The red heat resistant layer or void-containing layer (porous layer) can have an infrared reflectance of about 2% or more. In other examples, the reflectance may be about 2.5% or more, about 3% or more, about 3.5% or more, or about 4% or more. Since the higher the numerical value of the reflectance means that the red heat resistant layer or void-containing layer (porous layer) can appropriately block and / or delay the heat applied to the optical laminate and / or the optical functional layer, its upper limit is not particularly limited. Exemplarily, the infrared reflectance may be about 10% or less, about 9% or less, about 8% or less, about 7% or less, about 6% or less, or about 5% or less.

[0075] As the anti-discoloration layer or the void-containing layer (porous layer), various layers can be applied without particular limitation as long as they have an appropriate transmittance applicable to the optical laminate and have the above characteristics (thermal diffusivity, surface area ratio, and / or reflectivity). As long as they have the above characteristics, prevention, mitigation, reduction, suppression, and / or delay of discoloration are possible. Therefore, theoretically, all are applicable in the present application as long as an appropriate transmittance is ensured. The transmittance required in the optical laminate described above can be about 70% or more, about 75% or more, about 80% or more, about 85% or more, or about 90% or more. The higher the value of the transmittance, the more suitable it is, and the upper limit thereof is not particularly limited. For example, the transmittance can be about 100% or less, about 95% or less, or about 90% or less. The transmittance described above can be the transmittance at any one wavelength within the range of visible light, for example, approximately 380 nm to 780 nm, or the transmittance at a certain region within the range or for the entire region, or the average transmittance. When applying a void-containing layer (porous layer) as the anti-discoloration layer or applying a laminate including the void-containing layer (porous layer), heat transfer can be effectively blocked by the voids present in the anti-discoloration layer. However, the voids may be disadvantageous from the perspective of transmittance because they scatter or diffract light within the optical laminate. However, in the present application, as described later, by controlling the form of the voids, a decrease in transmittance due to the scattering or diffraction of light does not occur, or at least such a decrease is limited to a level that does not cause problems in use.

[0076] As the anti-discoloration layer, for example, a void-containing layer (porous layer) can be applied, or a layer containing a void-containing layer (porous layer) can be applied. That is, as described above, in the present application, the anti-discoloration layer can refer to the void-containing layer (porous layer) itself, or can also refer to a laminate containing the void-containing layer (porous layer) as long as the purpose of preventing discoloration is satisfied. In one example, the anti-discoloration layer can exhibit the above-mentioned properties (thermal diffusivity, surface area ratio, and / or infrared reflectance) by including the void-containing layer (porous layer). Therefore, the above-mentioned thermal diffusivity, surface area ratio, and / or infrared reflectance can be for the void-containing layer (porous layer) or at least for a laminate containing the void-containing layer (porous layer). The types of other elements included in the anti-discoloration layer together with the void-containing layer (porous layer) are not particularly limited, and can be, for example, elements constituting an optical laminate such as the polarizing layer or its protective film, retardation film, etc.

[0077] The void-containing layer is a layer containing at least one or more voids inside. Through such voids, the anti-discoloration layer can perform functions of preventing, alleviating, reducing, suppressing, and / or delaying heat transfer. When the void-containing layer is referred to as a porous layer in the present application, at least two or more voids are included inside the void-containing layer. In order to ensure the above-mentioned physical properties, such as thermal diffusivity, surface area ratio, and / or reflectivity, it is important for the anti-discoloration layer to include the void-containing layer (porous layer). At this time, the form of the voids included in the void-containing layer (porous layer) is not particularly limited, and for example, a substantially spherical or elliptical form, or other various forms of voids can all be applied.

[0078] The size (diameter) of the voids can be in the range of approximately 0.5 nm to 100 nm. The size of the voids, when the voids are spherical, means the particle diameter thereof, and when the voids are not spherical, it is the particle diameter of the sphere when the voids are assumed to be a sphere of the same volume. In other examples, the size of the voids is about 1 nm or more, about 2 nm or more, about 3 nm or more, about 4 nm or more, about 5 nm or more, about 6 nm or more, about 7 nm or more, about 8 nm or more, about 9 nm or more, about 10 nm or more, about 11 nm or more, about 12 nm or more, about 13 nm or more, about 14 nm or more, about 15 nm or more, about 16 nm or more, about 17 nm or more, about 18 nm or more, about 19 nm or more, about 20 nm or more, about 21 nm or more, about 22 nm or more, about 23 nm or more, about 24 nm or more, about 25 nm or more, about 26 nm or more, about 27 nm or more, about 28 nm or more, about 29 nm or more, about 31 nm or more, about 32 nm or more, about 33 nm or more, about 34 nm or more, about 35 nm or more, about 36 nm or more, about 37 nm or more or about 38 nm or more, or about 99 nm or less, about 98 nm or less, about 97 nm or less, about 96 nm or less, about 95 nm or less, about 94 nm or less, about 93 nm or less, about 92 nm or less, about 91 nm or less, about 90 nm or less, about 89 nm or less, about 88 nm or less, about 87 nm or less, about 86 nm or less, about 85 nm or less, about 84 nm or less, about 83 nm or less, about 82 nm or less, about 81 nm or less, about 79 nm or less, about 78 nm or less, about 77 nm or less, about 76 nm or less, about 75 nm or less, about 74 nm or less, about 73 nm or less, about 72 nm or less, about 71 nm or less, about 69 nm or less, about 68 nm or less, about 67 nm or less, about 66 nm or less, about 65 nm or less, about 64 nm or less, about 63 nm or less, about 62 nm or less, about 61 nm or less, about 59 nm or less, about 58 nm or less, about 57 nm or less, about 56 nm or less, about 55 nm or less, about 54 nm or less, about 53 nm or less, about 52 nm or less, about 51 nm or less, about 50 nm or less, about 49 nm or less, about 48 nm or less, about 47 nm or less, about 46 nm or less or about 45 nm or less may be sufficient.

[0079] In order to maximize the effect of the anti-reddening layer, ensure the above-described physical properties (thermal diffusivity, surface area ratio and / or reflectivity, etc.), and also maintain its transmittance, the position or distribution of the voids in the void-containing layer (porous layer) can be controlled.

[0080] For example, the anti-reddening layer or the void-containing layer (porous layer) has a log value graph of the scattering intensity of small angle X-ray scattering (SAXS) analysis in the range of 0.06 nm -1 ~0.209 nm -1 and can show at least one peak within the range of the scattering vector. The characteristic reflects the average distance between voids. For example, the smaller the scattering vector showing the peak, the more the average distance between voids in the anti-reddening layer or the void-containing layer (porous layer) tends to be far, and conversely, the larger it is, the closer the average distance between voids tends to be.

[0081] If the scattering vector is about 0.06 nm -1 or more, it is advantageous in terms of the property of being able to block or reduce the heat applied by appropriately dense voids in the anti-reddening layer or the void-containing layer (porous layer). Also, if the vector is about 0.209 nm -1 or less, the voids are arranged at appropriate intervals in the anti-reddening layer or the void-containing layer (porous layer), and the roughness of the surface of the anti-reddening layer or the void-containing layer (porous layer) is maintained at an appropriate level, which can make it easier to apply the anti-reddening layer or the void-containing layer (porous layer) to the optical laminate. Also, the transmittance of the anti-reddening layer within the range of the scattering vector can be maintained within an appropriate range. The scattering vector at which the peak is confirmed is, in other examples, about 0.065 nm -1 or more, about 0.07 nm -1 or more, about 0.075 nm -1 or more, about 0.08 nm -1 or more, about 0.085 nm -1 or more, about 0.09 nm -1 or more, about 0.095 nm -1 or more or 0.1 nm -1 or more may also be possible, and about 0.205 nm -1 or less, about 0.2 nm -1 or less, about 0.19 nm -1 or less, about 0.185 nm -1The following is about 0.18 nm -1 or less or about 0.16 nm -1 It may be the following.

[0082] In the above, the peak is an extreme value or an inflection point where the log value of the scattering intensity appears convex upward in the graph of the log value of the scattering intensity confirmed by the above analysis. The scattering vector is a value defined by the following formula 5, and within the range of such a scattering vector, at least one or more of the peaks can be confirmed.

[0083] [Formula 5] q = 4πsin(θ / λ)

[0084] In Formula 5, q is the scattering vector, θ is a value that is half of the scattering angle, and λ is the wavelength of the irradiated X-ray (unit: nm).

[0085] The method for proceeding with the evaluation of small-angle X-ray scattering follows the description of the examples in this specification.

[0086] The anti-reddening layer or the void-containing layer (porous layer) may have a value of A satisfying the following formula 6 of 1.5 or less, a value of B in the range of 0 to 0.01, and a value of C in the range of 0 to 0.001.

[0087] [Formula 6] [Number]

[0088] In Formula 6, n(λ) is the refractive index of the anti-reddening layer or the void-containing layer (porous layer) at the wavelength λ, and λ is any one wavelength in the range of 300 to 1800 nm.

[0089] Equation 6 is obtained by fitting the ellipticity of polarization measured by ellipsometry for the anti-reddening layer or the void-containing layer (porous layer) using the so-called Cauchy model. When the anti-reddening layer or the void-containing layer (porous layer) has the values of A, B, and C within the above-described range that satisfy Equation 6, the anti-reddening layer or the void-containing layer (porous layer) may have void characteristics capable of expressing an anti-reddening function. Equation 6 reflects the refractive index characteristics exhibited by the anti-reddening layer or the void-containing layer (porous layer). The overall refractive index of the anti-reddening layer or the void-containing layer (porous layer) is determined by the refractive index of the voids constituting the anti-reddening layer or the void-containing layer (porous layer) and the refractive index of other components other than the voids such as a binder. Therefore, the values of A, B, and C in Equation 6 for the anti-reddening layer or the void-containing layer (porous layer) can reflect the amount of voids in the anti-reddening layer. In one exemplary case, if the values of A, B, and / or C are within the above range, while the voids in the anti-reddening layer or the void-containing layer (porous layer) are present at a level capable of appropriately blocking or delaying the transfer of heat, the surface roughness, etc. of the anti-reddening layer or the void-containing layer (porous layer) is maintained at an appropriate level, and the application of the anti-reddening layer or the void-containing layer (porous layer) to the optical laminate can be made easier. Also, within the range of the values of A, B, and / or C, the transmittance in the optical laminate of the anti-reddening layer or the void-containing layer (porous layer) can be stably maintained.

[0090] In other examples, the value of A may be about 1.1 or more, about 1.15 or more, about 1.2 or more, about 1.25 or more, or about 1.3 or more. In other examples, the value of B is about 0.0001 or more, about 0.0002 or more, about 0.0003 or more, about 0.0004 or more, about 0.0005 or more, about 0.0006 or more, or about 0.0007 or more, or may be on the order of about 0.009 or less, about 0.008 or less, about 0.007 or less, about 0.006 or less, about 0.005 or less, or about 0.004 or less. In other examples, the value of C is about 0.000001 or more, about 0.000002 or more, about 0.000003 or more, about 0.000004 or more, about 0.000005 or more, about 0.000006 or more, about 0.000007 or more, about 0.000008 or more, about 0.000009 or more, about 0.00001 or more, about 0.00002 or more, about 0.00003 or more, about 0.00004 or more, about 0.00005 or more, about 0.00006, or about 0.00007 or more, or may be on the order of about 0.0009 or less, about 0.0008 or less, about 0.0007 or less, about 0.0006 or less, about 0.0005 or less, or about 0.0004 or less.

[0091] In Equation 6, λ is any one wavelength within the range of about 300 to about 1800 nm. In one example, it is about 400 nm or more or about 500 nm or more, or about 1700 nm or less, about 1600 nm or less, about 1500 nm or less, about 1400 nm or less, about 1300 nm or less, about 1200 nm or less, about 1100 nm or less, about 1000 nm or less, about 900 nm or less, about 800 nm or less, about 700 nm or less, or about 600 nm or less, or may be a wavelength range of about 550 nm. The anti-reddening layer or void-containing layer (porous layer) that satisfies Equation 6 may have a refractive index (based on a wavelength of 550 nm) of substantially 1.5 or less. In other examples, the refractive index may be about 1.1 or more or about 1.15 or more.

[0092] In the anti-oxidation layer or void-containing layer (porous layer), the volume fraction of voids can be about 0.1 or more. The volume fraction is the ratio of the volume of the space occupied by voids when the total volume of the anti-oxidation layer or void-containing layer (porous layer) is converted to 1. In such a range, the anti-oxidation layer or void-containing layer (porous layer) can appropriately block or reduce the heat transfer. Also, within the above range, the transmittance in the optical laminate of the anti-oxidation layer or void-containing layer (porous layer) can be stably maintained. The volume fraction can be measured by checking the density, mass, volume, etc. of the anti-oxidation layer or void-containing layer (porous layer) through the buoyancy method or the like, or as described later, when the anti-oxidation layer or void-containing layer (porous layer) is formed using hollow particles, it can be confirmed through the amount of hollow particles applied and the amount of binder, etc.

[0093] The anti-oxidation layer or void-containing layer (porous layer) can be formed in various ways. A typical method for forming a layer containing voids is a method of applying hollow particles. Thus, in one example, the anti-oxidation layer can include at least a binder and hollow particles.

[0094] By controlling the refractive index of the shell part of the binder and hollow particles, the size distribution of the hollow particles and the pores inside them, the amount of hollow particles, etc., the above-described characteristics (thermal diffusivity (mathematical formula 4), surface characteristics (surface area ratio of AFM), infrared reflectance, visible light transmittance, SAXS characteristics, volume fraction, and / or refractive index characteristics) can be satisfied.

[0095] As the binder, various types can be applied without special restrictions. For example, as the binder, various curable resin compositions applicable to optics can be applied. Examples of applicable optical resins include acrylic, epoxy, and / or silicone-based resins, etc., and the binder can be formed by applying the resin or a precursor capable of forming it. Such a resin or precursor can be curable, for example, a substance that cures upon irradiation with light such as ultraviolet rays or electron beams, a substance that cures by heat, or a substance that cures by other actions such as moisture.

[0096] As the binder, those having a refractive index (based on a wavelength of 550 nm) within the range of approximately 1.1 to 1.6 can be applied. Under such a refractive index range, a red-resistant layer that satisfies the above-mentioned formula 6 can be easily formed in combination with the hollow particles. In other examples, the refractive index can be, for example, about 1.15 or more, about 1.2 or more, about 1.25 or more, about 1.3 or more, about 1.35 or more, or about 1.4 or more, or about 1.55 or less or about 1.5 or less.

[0097] A typical binder that satisfies such a refractive index is an acrylic binder. The binder of the red-resistant layer can contain a polymerized unit of a polymerizable acrylic compound.

[0098] In one example, the acrylic compound is an alkyl (meth)acrylate or alkoxy (meth)acrylate having an alkyl group or alkoxy group with 1 to 20 carbon atoms, 1 to 16 carbon atoms, 1 to 12 carbon atoms, 1 to 8 carbon atoms, or 1 to 4 carbon atoms; a monofunctional acrylate compound such as hydroxyalkyl (meth)acrylate such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, or 8-hydroxyoctyl (meth)acrylate; 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, neopentyl glycol adipate di(meth)acrylate, hydroxy pivalic acid neopentyl glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, caprolactone-modified cyclopentenyl di(meth)acrylate, ethylene oxide-modified di(meth)acrylate, di(meth)acryloxyethyl isocyanurate, allylated cyclohexyl di(meth)acrylate, tricyclodecane dimethanol (meth)acrylate, dimethylol dicyclopentane di(meth)acrylate, ethylene oxide-modified hexahydrophthalic acid di(meth)acrylate, tricyclodecane dimethanol (meth)acrylate, neopentyl glycol-modified trimethylpropane di(meth)acrylate, adamantane di(meth)acrylate, or 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene, etc., such as bifunctional acrylates;Trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid-modified dipentaerythritol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propylene oxide-modified trimethylolpropane tri(meth)acrylate, trifunctional urethane (meth)acrylate or trifunctional acrylates such as tris(meth)acryloxyethyl isocyanurate; tetrafunctional acrylates such as diglycerin tetra(meth)acrylate or pentaerythritol tetra(meth)acrylate; pentafunctional acrylates such as propionic acid-modified dipentaerythritol penta(meth)acrylate; and hexafunctional acrylates such as dipentaerythritol hexa(meth)acrylate, caprolactone-modified dipentaerythritol hexa(meth)acrylate or urethane (meth)acrylate (e.g., reaction product of isocyanate monomer and trimethylolpropane tri(meth)acrylate) can be used.;

[0099] As the polyfunctional acrylate, a compound called a so-called photocurable oligomer in the art, such as urethane acrylate, epoxy acrylate, polyester acrylate or polyether acrylate, can also be used. One or more appropriate types among the above compounds can be selected and used.;

[0100] The type of the binder for forming the anti-reddening layer or the void-containing layer (porous layer) is not limited to the above, and all other various optical materials can be applied.;

[0101] In order to ensure appropriate void characteristics that, when combined with hollow particles, satisfy the desired properties (thermal diffusivity (Equation 4), surface properties (AFM surface area ratio), infrared reflectance, visible light transmittance, SAXS properties, volume fraction, and / or refractive index properties), among the types described above, polyfunctional acrylates can be applied as the binder. That is, the binder can include a polymer of the polyfunctional acrylate. A polyfunctional acrylate is a compound having at least two or more polymerizable functional groups (acryloyl group, methacryloyl group, acryloyloxy group, or methacryloyloxy group). In other examples, the number of the acrylic polymerizable functional groups can be 3 or more, or 10 or less, 9 or less, 8 or less, 7 or less, 6 or less, 5 or less, 4 or less, or 3 or less. As such a polyfunctional acrylate, a compound having no hydroxy group and no ring structure (for example, an aromatic ring structure or a dicyclopentadiene structure) is applied, which is advantageous in forming an anti-reddening layer in which the thermal diffusivity (Equation 4), surface properties (AFM surface area ratio), infrared reflectance, visible light transmittance, SAXS properties, volume fraction, and / or refractive index properties are stably ensured through the desired degree of crosslinking and pore characteristics. For the same reason, it is better that the binder of the anti-reddening layer (void-containing layer (porous layer)) has no hydroxy group or ring structure, or, even if present, the ratio is limited. Also, as the polyfunctional acrylate, using a compound having a molecular weight in the range of about 150 to about 1,000 g / mol is advantageous in forming an anti-reddening layer in which the thermal diffusivity (Equation 4), surface properties (AFM surface area ratio), infrared reflectance, visible light transmittance, SAXS properties, volume fraction, and / or refractive index properties are stably ensured through the desired degree of crosslinking and pore characteristics.In other examples, the molecular weight is about 170 g / mol or more, about 190 g / mol or more, about 210 g / mol or more, about 230 g / mol or more, about 250 g / mol or more, about 270 g / mol or more, or about 290 g / mol or more, or about 980 g / mol or less, about 960 g / mol or less, about 940 g / mol or less, about 920 g / mol or less, about 900 g / mol or less, about 880 g / mol or less, about 860 g / mol or less, about 840 g / mol or less, about 820 g / mol or less, about 800 g / mol or less, about 780 g / mol or less, about 760 g / mol or less, about 740 g / mol or less, about 720 g / mol or less, about 700 g / mol or less, about 680 g / mol or less, about 660 g / mol or less, about 640 g / mol or less, about 620 g / mol or less, about 600 g / mol or less, about 580 g / mol or less, about 560 g / mol or less, about 540 g / mol or less, about 520 g / mol or less, about 500 g / mol or less, about 480 g / mol or less, about 460 g / mol or less, about 440 g / mol or less, about 420 g / mol or less, about 400 g / mol or less, about 380 g / mol or less, about 360 g / mol or less, about 340 g / mol or less, about 320 g / mol or less, or about 300 g / mol or less. From the viewpoint of more efficiently ensuring the desired properties, the binder can substantially contain the polyfunctional acrylate as the main component. Therefore, the weight ratio of the polyfunctional acrylate in the binder can be about 50% or more, about 52% or more, about 54% or more, about 56% or more, about 58% or more, about 60% or more, about 62% or more, about 64% or more, about 66% or more, about 68% or more, about 70% or more, about 72% or more, about 74% or more, about 76% or more, about 78% or more, about 80% or more, about 82% or more, about 84% or more, about 86% or more, about 88% or more, about 90% or more, about 92% or more, about 94% or more, about 96% or more, or about 98% or more, and this ratio can be about 100% or less or less than about 100%. The ratio is the ratio of the polyfunctional acrylate in the binder. For example, when the void-containing layer (porous layer) is a layer containing a binder and hollow particles, it can be a ratio based on the weight obtained by subtracting the hollow particles from the total weight of the void-containing layer (porous layer).

[0102] As the hollow particles, for example, in order to satisfy the above-mentioned physical properties, particles having a specific particle size distribution can be used. For example, as the hollow particles, in the weight cumulative curve of the particle size distribution, the D10 particle size is about 20 nm to about 50 nm, or about 25 nm to about 50 nm, the D50 particle size is about 55 nm to about 100 nm, or about 50 nm to about 95 nm, and the D90 particle size is about 100 nm to about 200 nm, or about 110 nm to about 180 nm. The particles within these ranges can be respectively applied. In the above, the D10, D50, and D90 particle sizes are respectively the values of the particle sizes corresponding to about 10 wt%, about 50 wt%, and about 90 wt% of the maximum value (100 wt%) in the cumulative distribution graph showing the weight by particle size with the total weight of the hollow particles being 100 wt%. Through the application of particles having the above particle size distribution, the desired anti-reddening layer can be effectively formed.

[0103] In other examples, the D10 particle size is about 21 nm or more, about 22 nm or more, about 23 nm or more, about 24 nm or more, about 25 nm or more, about 26 nm or more, about 27 nm or more, about 28 nm or more, about 29 nm or more, about 30 nm or more, about 31 nm or more or 32 nm or more, or about 49 nm or less, about 48 nm or less, about 47 nm or less, about 46 nm or less, about 45 nm or less, about 44 nm or less, about 43 nm or less, about 42 nm or less, about 41 nm or less, about 40 nm or less, about 39 nm or less, about 38 nm or less, about 37 nm or less, about 36 nm or less, about 35 nm or less, about 34 nm or less or about 33 nm or less.

[0104] In other examples, the D50 particle size may be about 56 nm or more, about 57 nm or more, about 58 nm or more, about 59 nm or more, about 60 nm or more, about 61 nm or more, or 62 nm or more, or about 99 nm or less, about 98 nm or less, about 97 nm or less, about 96 nm or less, about 95 nm or less, about 94 nm or less, about 93 nm or less, about 92 nm or less, about 91 nm or less, about 90 nm or less, about 89 nm or less, about 88 nm or less, about 87 nm or less, about 86 nm or less, about 85 nm or less, about 84 nm or less, about 83 nm or less, about 82 nm or less, about 81 nm or less, about 79 nm or less, about 78 nm or less, about 77 nm or less, about 76 nm or less, about 75 nm or less, about 74 nm or less, about 73 nm or less, about 72 nm or less, about 71 nm or less, or about 70 nm or less.

[0105] In other examples, the D90 particle size may be about 111 nm or more, about 112 nm or more, about 113 nm or more, about 114 nm or more, about 115 nm or more, about 116 nm or more, about 117 nm or more, about 118 nm or more, about 119 nm or more, about 120 nm or more, about 121 nm or more, about 122 nm or more, or 123 nm or more, or about 179 nm or less, about 178 nm or less, about 177 nm or less, about 176 nm or less, about 175 nm or less, about 174 nm or less, about 173 nm or less, about 172 nm or less, about 171 nm or less, about 170 nm or less, about 169 nm or less, about 168 nm or less, about 167 nm or less, about 166 nm or less, about 165 nm or less, about 164 nm or less, about 163 nm or less, about 162 nm or less, about 161 nm or less, about 160 nm or less, about 159 nm or less, about 158 nm or less, about 157 nm or less, about 156 nm or less, about 155 nm or less, about 154 nm or less, about 153 nm or less, about 152 nm or less, about 151 nm or less, about 150 nm or less, about 149 nm or less, about 148 nm or less, about 147 nm or less, about 146 nm or less, about 145 nm or less, about 144 nm or less, about 143 nm or less, about 142 nm or less, about 141 nm or less, about 140 nm or less, about 139 nm or less, about 138 nm or less, about 137 nm or less, about 136 nm or less, about 135 nm or less, about 134 nm or less, about 133 nm or less, about 132 nm or less, about 131 nm or less, about 130 nm or less, about 129 nm or less, about 128 nm or less, about 127 nm or less, or about 126 nm or less.

[0106] As the hollow particles, particles having pore sizes corresponding to the size of the voids can be applied. Therefore, the size of the pores can be in the range of about 0.5 nm to about 100 nm.

[0107] In other examples, the size of the pores is about 1 nm or more, about 2 nm or more, about 3 nm or more, about 4 nm or more, about 5 nm or more, about 6 nm or more, about 7 nm or more, about 8 nm or more, about 9 nm or more, about 10 nm or more, about 11 nm or more, about 12 nm or more, about 13 nm or more, about 14 nm or more, about 15 nm or more, about 16 nm or more, about 17 nm or more, about 18 nm or more, about 19 nm or more, about 20 nm or more, about 21 nm or more, about 22 nm or more, about 23 nm or more, about 24 nm or more, about 25 nm or more, about 26 nm or more, about 27 nm or more, about 28 nm or more, about 29 nm or more, about 31 nm or more, about 32 nm or more, about 33 nm or more, about 34 nm or more, about 35 nm or more, about 36 nm or more, about 37 nm or more or about 38 nm or more, or about 99 nm or less, about 98 nm or less, about 97 nm or less, about 96 nm or less, about 95 nm or less, about 94 nm or less, about 93 nm or less, about 92 nm or less, about 91 nm or less, about 90 nm or less, about 89 nm or less, about 88 nm or less, about 87 nm or less, about 86 nm or less, about 85 nm or less, about 84 nm or less, about 83 nm or less, about 82 nm or less, about 81 nm or less, about 79 nm or less, about 78 nm or less, about 77 nm or less, about 76 nm or less, about 75 nm or less, about 74 nm or less, about 73 nm or less, about 72 nm or less, about 71 nm or less, about 69 nm or less, about 68 nm or less, about 67 nm or less, about 66 nm or less, about 65 nm or less, about 64 nm or less, about 63 nm or less, about 62 nm or less, about 61 nm or less, about 59 nm or less, about 58 nm or less, about 57 nm or less, about 56 nm or less, about 55 nm or less, about 54 nm or less, about 53 nm or less, about 52 nm or less, about 51 nm or less, about 50 nm or less, about 49 nm or less, about 48 nm or less, about 47 nm or less, about 46 nm or less or about 45 nm or less.

[0108] As the hollow particles, as long as they have the above-described characteristics and can exhibit the above-described characteristics (thermal diffusivity (mathematical formula 4), surface characteristics (surface area ratio of AFM), infrared reflectance, visible light transmittance, SAXS characteristics, volume fraction, and / or refractive index characteristics) together with the binder, various types can be applied without particular limitation.

[0109] For example, as the hollow particles, organic particles in which the shell portion is made of an organic substance, inorganic particles made of an inorganic substance, and / or organic-inorganic particles made of an organic-inorganic substance can be used. Examples of such particles include acrylic particles such as PMMA (poly(methyl methacrylate)), epoxy particles, nylon particles, styrene particles, and / or copolymer particles of styrene / vinyl monomers, and inorganic particles such as silica particles, alumina particles, indium oxide particles, tin oxide particles, zirconium oxide particles, zinc oxide particles, and / or titania particles, but are not limited thereto.

[0110] The anti-oxidation layer or void-containing layer (porous layer) can contain the hollow particles at a ratio of about 5% by weight or more. In other examples, the ratio can be about 10% by weight or more, about 15% by weight or more, about 20% by weight or more, about 25% by weight or more, about 30% by weight or more, about 35% by weight or more, about 40% by weight or more, about 45% by weight or more, about 50% by weight or more, about 55% by weight or more, about 60% by weight or more, about 65% by weight or more, about 70% by weight or more, about 75% by weight or more, about 80% by weight or more, about 85% by weight or more, about 90% by weight or more, about 95% by weight or more, about 100% by weight or more, about 105% by weight or more, about 110% by weight or more, about 115% by weight or more, about 120% by weight or more, about 125% by weight or more, about 130% by weight or more, about 135% by weight or more, about 140% by weight or more, about 145% by weight or more, about 150% by weight or more, about 155% by weight or more, about 160% by weight or more, about 165% by weight or more, about 170% by weight or more, about 175% by weight or more, or about 180% by weight or more. In other examples, the ratio can be about 9,000% by weight or less, about 8,000% by weight or less, about 7,000% by weight or less, about 6,000% by weight or less, about 5,000% by weight or less, about 4,000% by weight or less, about 3,000% by weight or less, about 2,000% by weight or less, about 1,000% by weight or less, about 900% by weight or less, about 800% by weight or less, about 700% by weight or less, about 600% by weight or less, about 500% by weight or less, about 400% by weight or less, about 300% by weight or less, about 250% by weight or less, about 240% by weight or less, about 230% by weight or less, about 220% by weight or less, about 210% by weight or less, or about 200% by weight or less.

[0111] The ratio of the hollow particles can be adjusted according to the desired properties. In one example, the anti-oxidation layer or void-containing layer (porous layer) can contain only the hollow particles as particles. That is, in such an example, the anti-oxidation layer or void-containing layer (porous layer) may not contain so-called solid particles. Thereby, the properties of the desired anti-oxidation layer or void-containing layer (porous layer) can be more appropriately realized.

[0112] In addition to the above components, the anti-reddening layer or void-containing layer (porous layer) can contain any additives known in the art as necessary. Examples of such additives can include hardeners or initiators for the binder, antioxidants, ultraviolet stabilizers, ultraviolet absorbers, color toners, defoamers, surfactants, and / or plasticizers.

[0113] The thickness of the anti-reddening layer or void-containing layer (porous layer) can be controlled to achieve the desired anti-reddening performance. For example, the anti-reddening layer or void-containing layer (porous layer) can have a thickness of about 200 nm or more. The desired anti-reddening performance can be effectively achieved within such a thickness range. In other examples, the thickness can be about 250 nm or more, about 300 nm or more, about 350 nm or more, about 400 nm or more, about 450 nm or more, about 500 nm or more, about 550 nm or more, about 600 nm or more, about 650 nm or more, about 700 nm or more, about 750 nm or more, about 800 nm or more, about 850 nm or more, or about 900 nm or more. The upper limit of the thickness is not particularly limited. Generally, the thicker the anti-reddening layer, the better the effect of preventing, alleviating, reducing, suppressing, and / or delaying heat. Therefore, the upper limit of the thickness of the anti-reddening layer or void-containing layer (porous layer) can be selected in consideration of the thickness required for the optical laminate as long as the effect of preventing, alleviating, reducing, suppressing, and / or delaying heat is ensured, and there is no special limitation. In one example, the thickness of the anti-reddening layer or void-containing layer (porous layer) can be about 3,000 nm or less, about 2,900 nm or less, about 2,800 nm or less, about 2,700 nm or less, about 2,600 nm or less, about 2,500 nm or less, about 2,400 nm or less, about 2,300 nm or less, about 2,200 nm or less, about 2,100 nm or less, about 2,000 nm or less, or about 1,950 nm or less.

[0114] The position of the anti-reddening layer within the optical laminate can also be controlled to ensure the desired anti-reddening performance.

[0115] The anti-reddening layer can be a layer separately included in the optical laminate or a layer formed by creating voids in a layer already existing within the optical laminate (e.g., an adhesive layer or a pressure-sensitive adhesive layer).

[0116] The position of the anti-reddening layer within the optical laminate can be controlled for the purpose, i.e., prevention, mitigation, reduction, suppression, and / or delay of reddening.

[0117] For example, the anti-reddening layer can be positioned as close as possible to the optical functional layer that is the main cause of reddening within the optical laminate. That is, the distance between the anti-reddening layer and the optical functional layer in the optical laminate can be controlled. The distance can be the shortest distance, the maximum distance, or the average distance between the opposing surfaces of the anti-reddening layer and the optical functional layer. In one exemplary case, the distance between the anti-reddening layer and the optical functional layer is within about 90 μm, within about 85 μm, within about 80 μm, within about 75 μm, within about 70 μm, within about 65 μm, within about 60 μm, within about 55 μm, within about 50 μm, within about 45 μm, within about 40 μm, within about 35 μm, within about 30 μm, within about 25 μm, within about 20 μm, within about 15 μm, within about 10 μm, within about 5 μm, within about 1 μm, within about 0.9 μm, within about 0.8 μm, within about 0.7 μm, within about 0.6 μm, within about 0.5 μm, within about 0.4 μm, within about 0.3 μm, or within about 0.2 μm. When the optical functional layer and the anti-reddening layer are positioned closest to each other, it is the case where the two layers are in contact with each other, and in such a case, the distance is 0 μm. Therefore, the lower limit of the distance is 0 μm. In other exemplary cases, the distance can be about 0.01 μm or more, about 0.02 μm or more, about 0.03 μm or more, about 0.04 μm or more, about 0.05 μm or more, about 0.09 μm or more, or about 0.1 μm or more.

[0118] Such an anti-reddening layer can be disposed at a position that does not form the outermost surface of the optical laminate. That is, the anti-reddening layer does not have to be the outermost layer of the optical laminate. Such a position setting may be required to exhibit the anti-reddening characteristics of the optical laminate and / or the optical functional layer.

[0119] In other examples, the optical laminate includes further layers together with the anti-reddening layer and the optical functional layer, and the anti-reddening layer may be located between the optical functional layer and the further layer. FIG. 1 is an example of such a layer configuration, showing the case where the further layer 30, the anti-reddening layer 20, and the optical functional layer 10 are sequentially formed. The further layer described above may be a protective film, an adhesive layer, an adhesive layer, a hard coat layer, an antireflection layer, a retardation layer, a brightness enhancement layer, etc., or a cover glass described later, but is not limited thereto.

[0120] With the above-described arrangement, the optical laminate of the present application can exhibit a somewhat high surface reflectance. That is, the anti-reddening layer of the present application can, due to its configuration, reduce the reflectance, but since such an anti-reddening layer is not present on the surface, the surface reflectance of the optical functional layer can be formed somewhat higher unless a separate antireflection layer or the like is formed. For example, the optical laminate can have a reflectance of about 2% or more. The reflectance described above can be the reflectance of light in the visible light region, for example, any one wavelength within the range of approximately 380 nm to 780 nm, or the reflectance for a certain region or the entire region within the range, or the average reflectance. In other examples, the reflectance can be about 2.5% or more, about 3% or more, about 3.5% or more, or about 4% or more, or can be about 10% or less, about 9% or less, about 8% or less, about 7% or less, about 6% or less, or about 5% or less.

[0121] With the above-described arrangement, the reddening phenomenon of the optical functional layer and / or the optical laminate can be effectively prevented, alleviated, reduced, suppressed, and / or delayed.

[0122] As long as the optical laminate basically includes the anti-reddening layer and the optical functional layer, it can also include various different layers.

[0123] Examples of such layers can include a protective film, an adhesive layer, an adhesive layer, a retardation film, a hard coat layer, or a low reflection layer for the optical laminate. The layer may be the further layer described above.

[0124] As the type of the further layer, a general configuration known in the art can be applied. For example, as the protective film, a resin film excellent in transparency, mechanical strength, thermal stability, moisture barrier property, isotropy, etc. can be used. Examples of such films include cellulose resin films such as TAC (triacetyl cellulose) films, polyester films, polyethersulfone films, polysulfone films, polycarbonate films, polyamide films, polyimide films, polyolefin films, acrylic films, cyclic polyolefin films such as norbornene resin films, polyarylate films, polystyrene films, polyvinyl alcohol films, etc. In addition to the protective layer in film form, a cured resin layer obtained by curing a thermally or photocurable resin such as (meth)acrylic, urethane, acrylic urethane, epoxy or silicone can also be applied to the protective film. Such a protective film can be formed on one or both sides of the optical functional layer.

[0125] As the retardation film, general materials can be applied. For example, a birefringent polymer film stretched uniaxially or biaxially, an alignment film of a liquid crystal polymer, a polymerized layer of a polymerizable liquid crystal compound, etc. can be applied. The thickness of the retardation film is not particularly limited.

[0126] The above-described protective film or retardation film can be attached to the optical functional layer or the like by an adhesive or the like. Such a protective film or the like may be subjected to an adhesion facilitation treatment such as corona treatment, plasma treatment, primer treatment or saponification treatment. Further, when the protective film is attached to the optical functional layer or the anti-reddening layer, a hard coat layer, a low reflection layer, an antireflection layer, an anti-sticking layer, a diffusion layer or a haze layer, etc. may be present on the surface of the protective film opposite to the surface attached to the optical functional layer or the anti-reddening layer.

[0127] In the optical laminate, in addition to the above-described protective film or retardation film, various elements such as a reflector or a transflective plate can also be present, and the type thereof is not particularly limited.

[0128] An adhesive can be used for bonding each layer of the optical laminate. Examples of the adhesive may include, but are not limited to, isocyanate-based adhesives, polyvinyl alcohol-based adhesives, gelatin-based adhesives, vinyl-based latex or aqueous polyesters. Usually, an aqueous adhesive can be used as the adhesive, but depending on the type of film to be attached, a solvent-free photocurable adhesive can also be used.

[0129] The optical laminate may include an adhesive layer for bonding to other members such as a liquid crystal panel or a cover glass. The adhesive forming the adhesive layer is not particularly limited, and for example, those based on acrylic polymers, silicone polymers, polyesters, polyurethanes, polyamides, polyethers, or polymers such as fluorine-based or rubber-based polymers can be appropriately selected and used. A release film can be temporarily attached and covered to the exposed surface of such an adhesive layer for the purpose of preventing contamination until it is put into practical use.

[0130] Such an optical laminate can have various structural forms. For example, FIG. 2 shows a structure in which an anti-reddening layer 20 is introduced in the structure of a polarizing plate, which is the most basic optical laminate. That is, the basic polarizing plate has a structure in which a protective film 301 is attached to at least one surface of the polarizing layer 100, and the anti-reddening layer 20 can be located between the polarizing layer 100 and the protective film 301. Adhesives or adhesives can be used for bonding each layer 100, 20, 301 in the structure of FIG. 2. In one example, the anti-reddening layer 20 of FIG. 2 can be a separate layer or itself can be the adhesive or adhesive. That is, hollow particles or the like can be introduced into the adhesive or adhesive to form a void-containing layer (porous layer) to serve as the anti-reddening layer.

[0131] Although a protective film 302 is also attached to the lower part of the polarizing layer 100 in FIG. 2, that is, the surface opposite to the red light-resistant layer 20, this protective film 302 may be omitted or may be another type of layer (for example, the retardation film or the cured resin layer described above). For example, an adhesive layer may be formed on the lower part of the protective film 302 existing on the surface opposite to the red light-resistant layer 20, that is, the surface opposite to the surface of the protective film 302 on the side of the polarizing layer 100, or an adhesive layer may be formed instead of the protective film 302.

[0132] FIG. 3 shows a case where, as a deformed structure, two protective films 301 and 302 exist on one surface of the polarizing layer 100, and a red light-resistant layer 20 exists between the protective films 301 and 302. Also in this case, an adhesive or an adhesive agent may be applied to the adhesion of the layers, and at this time, the red light-resistant layer 20 may be an adhesive or an adhesive agent. Matters regarding the protective film 303 existing below the polarizing layer 100 in such a structure are the same as those for the protective film 302 existing below the polarizing layer 100 in the structure of FIG. 2.

[0133] The structures of FIGS. 2 and 3 are one example of the present application, and the optical laminate of the present application may be configured in various other structures.

[0134] The present application also relates to a display device including the optical laminate. The type of the display device can be various without special restrictions, and for example, it can be a known LCD (Liquid Crystal Display) or OLED (Organic Light Emitting Display), etc. In such a display device, the optical laminate can be applied in a normal manner.

[0135] In particular, the optical laminate is effectively applied to a display device including a so-called cover glass.

[0136] Such a device usually includes a cover glass and an optical laminate adhered to the cover glass with so-called OCA (Optical Clear Adhesive), OCR (Optical Clear Resin), etc., and the laminate of the present application can be applied as the optical laminate. Therefore, the display device includes a cover glass and an optical laminate adhered to the cover glass, and the optical laminate can include the optical functional layer and an anti-reddening layer formed on at least one surface of the optical functional layer. At this time, the anti-reddening layer can be located between the cover glass and the optical functional layer.

[0137] Generally, a display device including a cover glass is applied to applications such as vehicle navigation. At this time, the reddening phenomenon becomes more problematic due to the cover glass with high thermal conductivity.

[0138] However, the optical laminate of the present application can be applied to a device with the above structure to solve the above problems.

[0139] The specific structure of the display device has no special limitation as long as the optical laminate of the present application is applied, and can follow a known structure.

Advantages of the Invention

[0140] In the present application, it is possible to provide an optical laminate or an anti-reddening layer applied thereto that does not induce the so-called reddening phenomenon even when driven or maintained under very harsh conditions (for example, very high temperature conditions).

Brief Description of the Drawings

[0141]

Figure 1

Figure 2

Figure 3

Mode for Carrying Out the Invention

[0142] Hereinafter, the polarizing layer and the like will be described more specifically through examples and the like according to the present application, but the scope of the present application is not limited thereto.

[0143] Hereinafter, each physical property of the polarizing layer and the like was measured by the following method.

[0144] 1. Measurement of Thickness The thickness of the polarizing layer, the red-resistant layer, and the like can be measured by applying a TEM (Transmission Electron Microscopy) device. After photographing the cross-section of the polarizing layer or the red-resistant layer with the TEM device, the thickness of the layer can be confirmed from the photographed image. In this example, the H-7650 product of Hitachi was used as the TEM device.

[0145] 2. Measurement of Particle Size Distribution and Pore Size of Hollow Particles The particle size distribution of the hollow particles was measured using the ELSZ-2000 equipment of Otsuka Electronics Co., Ltd. Also, the particle diameter and pore size of the hollow particles were measured by applying a TEM (Transmission Electron Microscopy) device. In this example, the H-7650 product of Hitachi was used as the TEM device. After photographing the cross-section (magnification of 10,000 times) of the red-resistant layer in the optical laminate (polarizing plate) manufactured in examples and the like using the TEM device, 50 hollow particles were arbitrarily selected, and their respective particle diameters and pore sizes were determined, and the arithmetic mean was taken as the representative value of the particle diameter and pore size.

[0146] 3. Measurement of CIE Color Coordinates The color coordinates were measured using a JASCO V-7100 spectrophotometer. The JASCO V-7100 spectrophotometer measures the color coordinates (TD color coordinates) at the point where the transmittance is minimized by rotating the absorption axis of the polarizing plate to be measured from 0 degrees to 360 degrees with respect to the absorption axis of the polarizer built into the device. After measuring the color coordinates (MD color coordinates) by further rotating the absorption axis of the polarizing plate to be measured 90 degrees clockwise at the point where the transmittance is minimized, a representative value of the color coordinates is derived based on each measured value. The color coordinates described in the examples of this specification are the color coordinates confirmed by the JASCO V-7100 spectrophotometer.

[0147] 4. Measurement of Transmittance and Reflectance The transmittance etc. of the polarizing plate alone were measured using a JASCO V-7100 spectrophotometer. The JASCO V-7100 spectrophotometer is a device that measures the transmittance etc. of the polarizing plate within the range of 380 to 780 nm and derives a representative value for the wavelength range. In this example, the transmittance confirmed by such a JASCO V-7100 spectrophotometer is described.

[0148] 5. Measurement of the Weight Ratio of Potassium K and Zinc Zn in the Polarizing Layer The weight ratio of potassium K and zinc Zn present in the polarizing layer was measured by the following method. First, after dissolving about 0.1 g of the polarizing layer in a nitric acid aqueous solution (2 mL) with a concentration of about 65 wt% at room temperature (about 25°C), it was diluted to 40 mL with water (deionized water), and then the weights of potassium K and zinc Zn contained in the polarizing layer were measured using ICP-OES (Optima 5300).

[0149] 6. Evaluation of the Thermal Diffusivity of the Anti-Reddening Layer The thermal diffusivity of the anti-reddening layer was measured by the following method. The thermal diffusivity was evaluated in a state where the anti-reddening layer was formed on a TAC (Triacetyl cellulose) film (manufactured by Hyosung Corporation, PG601F) with a thickness of approximately 60 μm in the method described in the following examples. At this time, the thickness of the anti-reddening layer is described in each example. Graphite coating was performed on the upper and lower surfaces of the TAC film / anti-reddening layer laminate. The graphite coating was formed using a GRAPHITE product of CRAMLIN. The product is a product that can perform graphite coating by a spray method. After spraying the product on the upper surface (the surface of the anti-reddening layer) and the lower surface (the TAC film) of the laminate once and drying it, a graphite layer was formed. Then, the thermal diffusivity was measured using an LFA 457 MicroFlash product of NETZSCH. The thermal diffusivity was measured based on a temperature of 95 °C, and was confirmed through the possibility of temperature transfer from one graphite surface to the other graphite surface. The thermal diffusivity of the laminate (anti-reddening layer / TAC film) was evaluated in such a manner, and in the examples, the relative ratio of the thermal diffusivity of the laminate to the TAC film was described.

[0150] 7. Evaluation of the infrared reflectance of the anti-reddening layer The infrared reflectance of the anti-reddening layer was confirmed by the following method. The infrared reflectance was evaluated in a state where the anti-reddening layer was formed on a TAC (Triacetyl cellulose) film with a thickness of approximately 60 μm in the method described in the following examples. At this time, the thickness of the anti-reddening layer is described in each example. A black tape (black PET film of TOMOEGAWA) was attached to the lower surface of the TAC film of the anti-reddening layer / TAC film laminate (the surface of the film on which the anti-reddening layer was not formed) for darkening treatment, and using a Solidspec 3700 equipment of SHIMADZU, the average reflectance in the wavelength range of 800 to 1300 nm was measured in the Reflectance mode. When using the device, the reflectance for a wavelength range at 1 nm intervals within the range of 800 nm to 1300 nm can be confirmed. In this example, the arithmetic mean value of the reflectance for each wavelength was used as the representative value of the infrared reflectance.

[0151] 8. Evaluation of Small Angle X-ray Scattering (SAXS) of the Red Resistance Layer The evaluation of the small angle X-ray scattering of the red resistance layer was carried out by the following method. The evaluation was carried out in a state where the red resistance layer was formed on a TAC (Triacetyl cellulose) film with a thickness of approximately 60 μm by the method described in the following examples. At this time, the thickness of the red resistance layer is described in each example. The laminate of the TAC film / red resistance layer was cut so that the horizontal and vertical sides were each about 1 cm to produce a test piece. The red resistance layer of the test piece was irradiated with X-rays having a wavelength of 0.0733 nm at a distance of 4 m to obtain the scattering intensity by the scattering vector. The measurement was performed at the 4C beamline of the Pohang Accelerator, and X-rays with a vertical size of about 0.023 mm and a horizontal size of about 0.3 mm were used. As the detector, a 2D mar CCD was used. After obtaining the image of the scattered 2D diffraction pattern, this was calibrated using the sample-to-detector distance obtained through a standard sample (polyethylene-block-polybutadiene-block-polystyrene, SEBS), and the scattering intensity by the scattering vector (q) was converted through circular average. At this time, the scattering vector was obtained by the following mathematical formula A.

[0152] [Mathematical formula A] q = 4πsin(θ / λ)

[0153] In Mathematical formula A, q is the scattering vector, θ is a numerical value that is half of the scattering angle (unit: degree), and λ is the wavelength of the irradiated X-ray (unit: angstrom (Å)).

[0154] 9. Measurement of Cauchy Parameter The refractive index and Cauchy Parameter of the anti-reddening layer were determined by the following method. The evaluation was carried out in a state where the anti-reddening layer was formed on a TAC (Triacetyl cellulose) film with a thickness of approximately 60 μm by the method described in the following examples. At this time, the thickness of the anti-reddening layer is described in each example. The properties were evaluated using equipment (J.A.Woollam Co.M-2000) for the anti-reddening layer of the laminate (anti-reddening layer / TAC film). The equipment was applied to the anti-reddening layer, and linearly polarized light was measured in the wavelength range of 380 nm to 1,000 nm under the condition of an incident angle of 70 degrees. The measured linearly polarized light data (Ellipsometry data (Psi(Ψ), delta(Δ))) was optimized (fitted) using Complete EASE software so that the MSE of the Cauchy model of the following general formula 1 was 25 or less, and n(λ), A, B, and C of the following formula 6 were obtained. The Roughness function was applied as on (range -20 to 50 nm) during the optimization process.

[0155] [Formula 6] [Number]

[0156] In Formula 6, n(λ) is the refractive index at a wavelength of λ nm.

[0157] 10. Evaluation of surface area ratio The surface area ratio of the anti-reddening layer (void-containing layer (porous layer)) was measured using an AFM instrument (Atomic Force Microscope, Park Systems, XE7). A sample was prepared by cutting a laminate having an anti-reddening layer (void-containing layer (porous layer)) formed on one side of a TAC film as described in the examples so that the horizontal and vertical lengths were 1 cm, and the sample was fixed to the stage of the instrument using carbon tape for measurement. As a probe (tip) for measurement, PPP-NCHR 10 (Force Constant: 42 N / m, Resonance Frequency 330 kHz) was used. The measurement conditions are as follows.

[0158] <Measurement Conditions> x-scan size: 1 μm y-scan size: 1 μm Scan rate: 0.7~1 Hz Z Servo Gain: 1 Set Point: 10~15 nm

[0159] The data measured under the above conditions was flattened under the following conditions using the XEI program.

[0160] <Flattening Conditions> Scope: Line Orientation: X and Y axis Regression Order: 1

[0161] After flattening, the surface area ratio was extracted using the Region tab in the XEI program.

[0162] Production Example 1. Production of Polarizing Layer (A) A PVA (poly(vinyl alcohol)) film with a thickness of about 30 μm (Nippon Gosei Co., Ltd., M3004L) was immersed in a dyeing solution at 28 °C containing 0.2 wt% iodine I₂ and 2.5 wt% potassium iodide KI for 60 seconds for dyeing treatment. Next, the dyed PVA film was immersed in an aqueous solution (crosslinking solution) at 35 °C containing 1 wt% boron and 3 wt% potassium iodide KI for 60 seconds for crosslinking treatment. After that, the crosslinked PVA film was stretched at a stretching ratio of 5.4 times using a method of stretching between rolls. The stretched PVA film was immersed in ion-exchanged water at 25 °C for 60 seconds for washing, and then immersed in an aqueous solution at 25 °C containing 2 wt% zinc nitrate and 5 wt% potassium iodide KI for 30 seconds. After that, the PVA film was dried at a temperature of 80 °C for 60 seconds to produce a PVA polarizing layer. The final thickness of the produced polarizing layer was about 12 μm, the potassium content was about 0.9 wt%, and the zinc content was about 0.3 wt%. Also, 1 / (1 + 0.025d / R) was about 0.9. Here, d is the thickness of the polarizing layer (12 μm), and R is the ratio K / Zn of the weight ratio K (unit: weight) of the potassium component contained in the polarizing layer to the weight ratio Zn (unit: weight) of the zinc component.

[0163] Production Example 2. Production of the porous layer (A) material TMPTA (trimethylolpropane triacrylate) was applied as a binder, and hollow silica particles were applied to produce a porous layer. As the hollow silica particles, particles with D10, D50, and D90 particle sizes of 32.1 nm, 62.6 nm, and 123.4 nm, respectively, were used. In this case, after forming the porous layer, the average pore size measured by TEM was approximately 38.3 nm, and the particle diameter was approximately 53 nm. The binder, the hollow silica particles, a fluorine-containing compound (RS-90, DIC Corporation), and an initiator (Irgacure 127, Ciba Corporation) were diluted in a solvent MIBK (methyl isobutyl ketone) at a weight ratio (binder: hollow silica particles: fluorine-containing compound: initiator) of 31:65:0.1:3.9 based on the solid content to produce a coating solution.

[0164] Production Example 3. Production of Porous Layer (B) Material TMPTA (trimethylolpropane triacrylate) was applied as a binder, and hollow silica particles (Hollow Silica Particle) were applied to produce a porous layer. As the hollow silica particles, particles with D10, D50, and D90 particle sizes of 39.9 nm, 70.6 nm, and 126.0 nm, respectively, were used. In this case, after forming the porous layer, the average pore size measured by TEM was approximately 44.1 nm, and the particle diameter was approximately 61 nm. The binder, the hollow silica particles, a fluorine-containing compound (RS-90, manufactured by DIC Corporation), and an initiator (Irgacure 127, manufactured by Ciba Corporation) were diluted in a solvent MIBK (methyl isobutyl ketone) at a weight ratio of 55.1:40:1.1:3.8 (binder:hollow silica particles:fluorine-containing compound:initiator) to produce a coating solution.

[0165] Production Example 4. Production of Porous Layer (C) Material PETA (Pentaerythritol triacrylate) was applied as a binder, and hollow silica particles (Hollow Silica Particle) were applied to produce a porous layer. As the hollow silica particles, particles with D10, D50, and D90 particle sizes of 39.9 nm, 70.6 nm, and 126.0 nm, respectively, were used. In this case, after forming the porous layer, the average pore size measured by TEM was approximately 44.1 nm, and the particle diameter was approximately 61 nm. The binder, the hollow silica particles, a fluorine-containing compound (RS-90, manufactured by DIC Corporation), and an initiator (Irgacure 127, manufactured by Ciba Corporation) were diluted in a solvent MIBK (methyl isobutyl ketone) at a weight ratio of 76.5:20:0.5:3.0 (binder:hollow silica particles:fluorine-containing compound:initiator) to produce a coating solution.

[0166] Production Example 5. Production of Resin Layer (A) Material PETA (Pentaerythritol triacrylate) was applied as a binder, and instead of applying hollow particles, Solid Silica Particles were applied to manufacture a resin layer material. As the Solid Silica Particles, particles with D10, D50, and D90 particle sizes of 43.1 nm, 69.9 nm, and 125.8 nm respectively were used. In this case, the particle diameter measured by TEM after forming the resin layer was approximately 60 nm. The binder, the Solid Silica Particles, a fluorine-containing compound (RS-90, manufactured by DIC), and an initiator (Irgacure 127, manufactured by Ciba) were diluted in a solvent MIBK (methyl isobutyl ketone) at a weight ratio of 31:65:0.1:3.9 (binder:Solid Silica Particles:fluorine-containing compound:initiator) to produce a coating solution.

[0167] Example 1. A general optical aqueous adhesive layer (thickness: 100 nm) was applied to the polarizing layer (A) obtained in Production Example 1, and a COP (Cycloolefin Polymer) film (manufacturer: Zeon) with a thickness of approximately 30 μm was attached as a protective film. Separately, a porous layer was formed on a TAC (Triacetyl cellulose) film (manufactured by Hyosung, PG601F) with a thickness of approximately 60 μm. The porous layer was coated with the porous layer (A) material of Production Example 2 using a Mayer bar, dried at about 60°C for about 1 minute, and then irradiated with ultraviolet light (252 mJ / cm 2 ) so as to have a final thickness of about 450 nm. The Surface Area Ratio measured with respect to the surface on the opposite side of the surface of the formed porous layer that contacts the TAC film was at a level of about 0.148. Next, the porous layer of the laminate of the porous layer and the TAC film was attached to the polarizing layer (A) of the laminate of the manufactured COP film and the polarizing layer (A) with the same aqueous adhesive (thickness: 100 nm). Next, an acrylic adhesive layer was formed on the lower part of the polarizing plate, and a polarizing plate (optical laminate) having a structure in which a protective film (COP film), an adhesive layer, a polarizing layer, an adhesive layer, a porous layer, a protective film (TAC film), and an adhesive layer were sequentially laminated was manufactured.

[0168] Example 2. A polarizing plate was manufactured in the same manner as in Example 1 except that the porous layer was changed. The porous layer was coated with the coating solution of Production Example 3 on the same TAC film as in Example 1 using a Mayer bar, dried at 60°C for 1 minute, and then irradiated with ultraviolet rays (252 mJ / cm 2 ) so as to have a final thickness of 600 nm. The surface area ratio measured with respect to the surface on the opposite side of the surface in contact with the TAC film of the formed porous layer was at a level of about 0.0359. A polarizing plate was fabricated in the same manner as in Example 1 except that the porous layer formed by the above method was applied.

[0169] Example 3. A polarizing plate was manufactured in the same manner as in Example 1 except that the porous layer was changed. Although the porous layer was formed in the same manner as in Example 1 using the coating material of Production Example 4, the final thickness was formed to be approximately 950 nm. The surface area ratio measured with respect to the surface on the opposite side of the surface in contact with the TAC film of the formed porous layer was at a level of about 0.109. A polarizing plate was fabricated in the same manner as in Example 1 except that the porous layer formed as described above was applied.

[0170] Comparative Example 1. A polarizing plate was manufactured in the same manner as in Example 1 except that the porous layer was not applied.

[0171] Comparative Example 2. A resin layer was formed on a TAC (Triacetyl cellulose) film (Hyosung Co., PG601F) having a thickness of approximately 60 μm. The resin layer (A) material of Production Example 5 was coated with a Mayer bar, dried at 60°C for about 1 minute, and then irradiated with ultraviolet rays (252 mJ / cm 2) Thus, a resin layer was formed so that the final thickness was about 450 nm. The surface area ratio measured with respect to the surface opposite to the surface in contact with the TAC film of the formed resin layer was at about 0.01 level. A general optical aqueous adhesive layer (thickness: 100 nm) was applied to the polarizing layer (A) obtained in Production Example 1, and a COP (Cycloolefin Polymer) film (manufacturer: Zeon) with a thickness of about 30 μm was attached as a protective film. The formed resin layer was attached to the polarizing layer (A) of the laminate of the manufactured COP film and the polarizing layer (A) with the same aqueous adhesive (thickness: 100 nm) as above. Next, an acrylic adhesive layer was formed on the lower part of the polarizing plate, and a polarizing plate (optical laminate) having a structure in which a protective film (COP film), an adhesive layer, a polarizing layer, an adhesive layer, a resin layer, a protective film (TAC film), and an adhesive layer were sequentially laminated was manufactured.

[0172] The characteristics of the porous layers formed in each of the above Examples were tabulated and described in Table 1 below (in the case of Comparative Example 1, no porous layer was formed; in the case of Comparative Example 2, the characteristics of the resin layer were described).

[0173]

Table 1

[0174] After conducting a heat resistance test on the above Examples and Comparative Examples, the single transmittance and the change amount of the color coordinate a * were evaluated and tabulated and described in Table 2 below. In the above heat resistance test, the entire upper and lower surfaces of the polarizing plate manufactured in each Example or Comparative Example were laminated in contact with a soda lime glass (Seowon Tech) having a thickness of about 1.1 mm, and then maintained at 105 °C for 250 hours. Also, it was observed whether a reddening phenomenon was confirmed with the naked eye, and if confirmed, it was marked as NG, and if not confirmed, it was marked as PASS and tabulated and described in Table 2 below (the unit of transmittance in Table 2 below is %).

[0175]

Table 2

Explanation of Symbols

[0176] Optical functional layer 10 Anti-reddening layer 20 Additional layer 30 Polarizing layer 100 Protective film 301 Protective film 302

Claims

1. An optical laminate including a polarizing layer containing a zinc component, an anti-reddening layer formed on one surface of the polarizing layer, and an adhesive layer for adhesion to another member which is a liquid crystal panel or a cover glass, wherein the anti-reddening layer is a void-containing layer or a laminate including a void-containing layer, the anti-reddening layer included in the optical laminate is disposed between the polarizing layer and the adhesive layer, the void-containing layer includes a binder and hollow particles, and the hollow particles have D10 particle size, D50 particle size, and D90 particle size within ranges of 25 nm to 50 nm, 50 nm to 95 nm, and 100 nm to 200 nm, respectively, in a weight cumulative curve of a particle size distribution, the optical laminate.

2. The optical laminate according to claim 1, wherein the polarizing layer is an iodine-based polarizing layer.

3. The optical laminate according to claim 1 or 2, wherein the polarizing layer satisfies the following formula 3: [Formula 3] 0.70 to 0.97 = 1 / (1 + 0.025d / R) In formula 3, d is the thickness (μm) of the polarizing layer, and R is the ratio (K / Zn) of the weight ratio (K) (unit: weight) of the potassium component contained in the polarizing layer to the weight ratio (Zn) (unit: weight) of the zinc component.

4. The anti-reddening layer shows at least one peak within the range of scattering vectors of 0.06 to 0.209 nm in the log value graph of the scattering intensity of small-angle X-ray scattering. －１ The optical laminate according to any one of claims 1 to 3.

5. The optical laminate according to any one of claims 1 to 4, wherein the anti-reddening layer has an A value satisfying the following formula 6 of 1.5 or less, a B value within a range of 0 to 0.01, and a C value within a range of 0 to 0.001: [Formula 6] 【Number 1】 In formula 6, n(λ) is the refractive index of the anti-reddening layer at a wavelength λ, and λ is any one wavelength within a range of 300 to 1800 nm.

6. The optical laminate according to any one of claims 1 to 5, wherein the binder includes a polymer of a polyfunctional acrylate having 2 to 10 polymerizable functional groups.

7. The optical laminate according to any one of claims 1 to 6, wherein the void-containing layer does not include solid particles.

8. The optical laminate according to any one of claims 1 to 7, wherein the anti-reddening layer has a thickness of 200 nm or more.

9. The optical laminate according to any one of claims 1 to 8, wherein the anti-reddening layer does not form an outermost surface.

10. The optical laminate according to any one of claims 1 to 9, wherein the distance between the anti-reddening layer and the polarizing layer is within 90 μm.

Images