Optical film, composition for forming coating layer, and electronic device

Abstract

The present invention relates to an optical film, a composition for forming a coating layer, and an electronic device that have excellent light absorption performance for near-infrared rays having a wavelength of 750 nm or more and 1500 nm or less, excellent light resistance and moisture resistance, and can achieve excellent light absorption performance even when exposed to harsh conditions.

Description

Technical Field

[0001] Cross-reference to Related Applications This application claims the benefit of priority based on Korean Patent Application Nos. 10-2022-0027487 and 10-2022-0027488 filed on March 3, 2022, and all the contents disclosed in the documents of the Korean patent applications are incorporated herein by reference.

[0002] The present invention relates to an optical film, a composition for forming a coating layer, and an electronic device.

Background Art

[0003] Virtual Reality (VR) refers to an artificial technology created using a computer or the like, which is similar to but not actual, a specific environment, situation, or the technology itself.

[0004] Also, Augmented Reality (AR) refers to a technology that synthesizes virtual objects and information into the actual environment to make them appear like objects existing in the original environment.

[0005] Mixed Reality (MR) or Hybrid Reality refers to creating a new environment or new information by combining the virtual world and the real world. In particular, when it is possible to interact in real time between what exists in reality and in virtuality in real time, it is called Mixed Reality.

[0006] At this time, the created virtual environment, situation, etc. stimulate the user's five senses and allow free entry and exit across the boundary between reality and imagination by providing a spatially and temporally realistic experience. Also, the user can not only simply immerse themselves in such an environment but also interact with what is realized in such an environment by using an actual device to add operations and commands.

[0007] That is, based on the real world, the user can interact with virtual objects to feel an enhanced sense of reality, recognize the actual environment where they are located, and at the same time recognize the virtual information presented on the actual video.

[0008] In such a technical field, a pupil recognition sensor is used to match the virtual reality image to the actual world that the user is looking at.

[0009] One of the tracking methods, the optical method, is a method of attaching an infrared LED to a pre-measured position and detecting it with a camera. When taking a photo, the camera captures the pupil detected by the infrared LED like the red-eye phenomenon caused by the reflection of light by the pupil, and the central vision is shown as coordinates by a designed algorithm. Therefore, by effectively blocking the external infrared region except for the infrared LED that detects the pupil, the error in the execution of augmented reality can be minimized.

[0010] Therefore, in order to apply it to augmented reality (AR) and minimize the error of the pupil recognition sensor, research on an optical film that can effectively block the near-infrared light flowing in from the outside is currently required.

Summary of the Invention

Problems to be Solved by the Invention

[0011] The present invention provides an optical film, a composition for forming a coating layer, and an electronic device that have excellent light absorption performance for near-infrared light with a wavelength of 750 nm or more and 1500 nm or less, excellent light resistance and moisture resistance, and can achieve excellent light absorption performance even when exposed to harsh conditions.

Means for Solving the Problems

[0012] This specification provides an optical film that includes a substrate and a coating layer formed on the substrate. The coating layer contains a vinyl cyanide compound-aromatic compound copolymer and a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less, has an initial average transmittance (T0) of 30% or more in the wavelength range of 800 nm to 1000 nm, and has a change rate of average transmittance calculated by the following Mathematical Formula 1 of 18% or less.

[0013] [Mathematical Formula 1] Change rate of average transmittance = [(Average transmittance (T1) of the optical film in the wavelength range of 800 nm to 1000 nm - Initial average transmittance (T0) of the optical film in the wavelength range of 800 nm to 1000 nm) / T0] × 100, where the optical film is exposed for 15 hours to 30 hours in the wavelength range of 300 nm to 400 nm.

[0014] Also, this specification provides an electronic device including the optical film.

[0015] Furthermore, this specification provides a composition for forming a coating layer, which contains a vinyl cyanide compound-aromatic compound copolymer and a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less. The vinyl cyanide compound-aromatic vinyl compound copolymer has a weight average molecular weight of 10,000 g / mol or more and 200,000 g / mol or less, and the vinyl cyanide compound-aromatic vinyl compound copolymer contains 10 parts by weight or more and 50 parts by weight or less of repeating units derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer.

[0016] Hereinafter, the optical film, the composition for forming a coating layer, and the electronic device according to specific embodiments of the invention will be described in more detail.

[0017] In this specification, "high temperature" can mean a temperature of 60°C or higher. For example, the high temperature can mean a temperature of 65°C or higher, 70°C or higher, 75°C or higher, 80°C or higher, 85°C or higher, or 90°C or higher. Its upper limit is not particularly limited, but it may be, for example, 110°C or lower, 105°C or lower, 100°C or lower, 95°C or lower, 90°C or lower, 85°C or lower, or 80°C or lower. When the temperature affects the characteristics of a substance, article, or each component, unless otherwise specified, the temperature condition under which the characteristics are measured or described can mean normal temperature (for example, a temperature at which no particular cooling or heating is performed, within the range of about 15 to 30°C).

[0018] Also, in this specification, "high humidity" can mean a relative humidity of 80% or higher. For example, high humidity conditions can mean conditions that satisfy a relative humidity of 85% or higher, 90% or higher, or 95% or higher. When the humidity affects the characteristics of a substance, article, or each component, unless otherwise specified, the humidity condition under which the characteristics are measured or described is when the relative humidity is lower than the high humidity condition. For example, it can be a relative humidity condition within the range of 15 or higher and less than 80%. Specifically, it can mean a relative humidity condition where the lower limit is 20% or higher, 25% or higher, 30% or higher, 35% or higher, 40% or higher and the upper limit is 75% or lower, 70% or lower, 65% or lower, or 60% or lower.

[0019] Furthermore, in this specification, high temperature / high humidity conditions can mean environmental conditions that satisfy any one or more of the above-mentioned high temperature conditions and high humidity conditions.

[0020] Unless explicitly mentioned in this specification, technical terms are only for referring to specific embodiments and are not intended to limit the present invention.

[0021] In this specification, the singular forms used also include the plural forms unless the context clearly indicates the contrary meaning.

[0022] As used herein, the meaning of "comprising" embodies specific characteristics, regions, integers, steps, operations, elements and / or components, and does not exclude the presence or addition of other specific characteristics, regions, integers, steps, operations, elements, components and / or groups.

[0023] Also, in this specification, the weight average molecular weight means the weight average molecular weight in terms of polystyrene (unit: g / mol) measured by the GPC method. In the process of measuring the weight average molecular weight in terms of polystyrene measured by the GPC method, a commonly known analyzer, detectors such as a refractive index detector, and analytical columns can be used, and the usually applied temperature conditions, solvents, and flow rates can be applied. Specific examples of the measurement conditions include a temperature of 25 °C, tetrahydrofuran (THF), and a flow rate of 1 mL / min.

[0024] According to an embodiment of the invention, there is provided an optical film including a substrate and a coating layer formed on the substrate, the coating layer including a vinyl cyanide compound-aromatic compound copolymer and a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less, having an initial average transmittance (T0) of 30% or more in the wavelength region of 800 nm to 1000 nm, and a change rate of the average transmittance calculated by the following formula 1 of 18% or less.

[0025] [Formula 1] Change rate of average transmittance = [(Average transmittance (T1) of the optical film in the wavelength region of 800 nm to 1000 nm after exposure for 15 hours to 30 hours in the wavelength region of 300 nm to 400 nm - Initial average transmittance (T0) of the optical film in the wavelength region of 800 nm to 1000 nm) / T0] × 100.

[0026] Dyes having a maximum absorption wavelength of 750 nm or more and 1500 nm or less are vulnerable to the stability against light. Conventionally, in the case of an optical film containing this, there has been a problem that the light resistance decreases and the light absorption performance of the dye decreases.

[0027] Therefore, the inventors have conducted research on an optical film that is excellent in light resistance and moisture resistance even when used under harsh conditions and can achieve excellent light absorption in the wavelength range of 750 nm or more and 1500 nm or less. In the case of an optical film containing a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less together with the vinyl cyanide compound-aromatic compound copolymer, the thermal and light oxidation stability of the vinyl cyanide compound-aromatic compound copolymer is excellent, and the generation of reactive species that affect the stability of the dye is small. By enhancing the stability of the dye, it has been confirmed that the finally manufactured optical film is excellent in light resistance and moisture resistance even when used under harsh conditions and can achieve excellent light absorption in the wavelength range of 750 nm or more and 1500 nm or less, and thus the invention has been completed.

[0028] Specifically, the change rate of the average transmittance calculated by the following formula 1 of the optical film may be 18% or less.

[0029] [Formula 1] Change rate of average transmittance = [(Average transmittance (T1) of the optical film in the wavelength range of 800 nm to 1000 nm - Initial average transmittance (T0) of the optical film in the wavelength range of 800 nm to 1000 nm) / T0] × 100 after exposure for 15 to 30 hours in the wavelength range of 300 nm to 400 nm.

[0030] The average transmittance is a value measured for an optical film having a thickness of 20 μm or more and 250 μm or less. The specific measurement method is not greatly limited. For example, it can be measured using a spectrophotometer such as solidspec-3700 of Shimadzu Corporation.

[0031] Specifically, for the optical film, the rate of change of the average transmittance calculated by the above formula (1) is 18% or less, 15% or less, 10% or less, 5% or less, 2% or less, 0.01% or more, 0.1% or more, 0.5% or more, or may be 0.01% or more and 10% or less, 0.01% or more and 5% or less, 0.01% or more and 2% or less, 0.1% or more and 10% or less, 0.1% or more and 5% or less, 0.1% or more and 2% or less, 0.5% or more and 10% or less, 0.5% or more and 5% or less, 0.5% or more and 2% or less.

[0032] When the rate of change of the average transmittance calculated by the above formula (1) is 10% or less, the optical film has excellent light resistance and the light absorption rate performance in the near-infrared wavelength range of 750 nm or more and 1500 nm or less does not decrease even under harsh conditions, realizing excellent light absorption, and an optical film suitable for applications such as Augmented Reality (AR) can be provided.

[0033] In the above formula (1), the initial average transmittance can mean an optical film that is not separately processed after production.

[0034] That is, in the above formula (1), the initial average transmittance may be 30% or more, 40% or more, 45% or more, 60% or less, 56% or less, 30% or more and 60% or less, 40% or more and 60% or less, 45% or more and 60% or less, 30% or more and 56% or less, 40% or more and 56% or less, 45% or more and 56% or less.

[0035] When the initial average transmittance of the optical film is 30% or more and 60% or less, the optical film has excellent light absorption rate for near-infrared light in the wavelength range of 750 nm or more and 1500 nm or less, and an optical film suitable for applications such as Augmented Reality (AR) can be provided.

[0036] In the formula (1), the average transmittance after exposure to ultraviolet light having a wavelength of 100 nm to 400 nm or 300 nm to 400 nm for 15 hours or more and 30 hours or less means the average transmittance in the wavelength range of 800 nm or more and 1000 nm or less measured after exposing the optical film of the embodiment to a light quantity of 0.10 to 1.00 W / cm 2 or 0.68 W / cm 2 using a QUV device (Q-Lab Corporation) or the like at this time.

[0037] After exposure in the wavelength range of 300 nm to 400 nm for 15 hours to 30 hours, the average transmittance (T1) of the optical film in the wavelength range of 800 nm to 1000 nm may be 30% or more and 65% or less.

[0038] Specifically, after exposure in the wavelength range of 300 nm to 400 nm for 15 hours to 30 hours, the average transmittance (T1) of the optical film in the wavelength range of 800 nm to 1000 nm may be 30% or more, 40% or more, 45% or more, 60% or less, 56% or less, 30% or more and 60% or less, 40% or more and 60% or less, 45% or more and 60% or less, 30% or more and 56% or less, 40% or more and 56% or less, 45% or more and 56% or less.

[0039] When the average transmittance (T1) of the optical film in the wavelength range of 800 nm to 1000 nm is 30% or more and 60% or less after exposure in the wavelength range of 300 nm to 400 nm for 15 hours to 30 hours, the optical film is excellent in light resistance and realizes an excellent light absorption rate for near-infrared light in the wavelength range of 750 nm or more and 1500 nm or less even under harsh conditions, and an optical film suitable for application to Augmented Reality (AR) or the like can be provided.

[0040] On the other hand, the optical film may have an initial average transmittance (T0) of 30% or more or 30% or more and 60% or less in the wavelength range of 800 nm to 1000 nm.

[0041] The average transmittance is a value measured for an optical film having a thickness of 20 μm or more and 250 μm or less. The specific measurement method is not greatly limited. For example, it can be measured using a spectrophotometer such as Shimadzu's SolidSpec-3700.

[0042] Specifically, the optical film may have an average transmittance of 30% or more, 40% or more, 45% or more, 60% or less, 56% or less, 30% or more and 60% or less, 40% or more and 60% or less, 45% or more and 60% or less, 30% or more and 56% or less, 40% or more and 56% or less, 45% or more and 56% or less with respect to wavelengths of 800 nm or more and 1000 nm or less.

[0043] When the average transmittance of the optical film with respect to wavelengths of 800 nm or more and 1000 nm or less is 30% or more and 60% or less, the optical film has excellent light absorption rate for near-infrared light in the wavelength range of 750 nm or more and 1500 nm or less, and an optical film suitable for applications such as Augmented Reality (AR) can be provided.

[0044] On the other hand, the optical film may have a change rate of average transmittance calculated by the following formula (2) of 10% or less.

[0045] [Formula (2)] Change rate of average transmittance =[(Average transmittance (T2) of the optical film in the wavelength range of 800 nm to 1000 nm after exposure to high temperature and high humidity conditions - Initial average transmittance (T0) of the optical film in the wavelength range of 800 nm to 1000 nm) / T0]×100

[0046] At this time, exposure under high temperature and high humidity conditions means exposure for 50 to 100 hours under temperature conditions of 70°C to 100°C and humidity conditions of 70% to 90%.

[0047] In the formula (2), the average transmittance is a value measured for an optical film having a thickness of 20 μm or more and 250 μm or less. The specific measurement method is not greatly limited. For example, it can be measured using a spectrophotometer such as Shimadzu's SolidSpec-3700.

[0048] Specifically, for the optical film, the change rate of the average transmittance calculated by the formula (2) may be 10% or less, 5% or less, 4.7% or less, 0.01% or more, 0.1% or more, 0.5% or more, or 0.01% or more and 10% or less, 0.01% or more and 5% or less, 0.01% or more and 4.7% or less, 0.1% or more and 10% or less, 0.1% or more and 5% or less, 0.1% or more and 4.7% or less, 0.5% or more and 10% or less, 0.5% or more and 5% or less, 0.5% or more and 4.7% or less.

[0049] When the change rate of the average transmittance calculated by the formula (2) is 10% or less, the optical film has excellent moisture resistance, and the light absorption rate performance does not decrease for near-infrared light in the wavelength range of 750 nm or more and 1500 nm or less even under harsh conditions, realizing excellent light absorption, and an optical film suitable for applications such as Augmented Reality (AR) can be provided.

[0050] In the formula (2), the initial average transmittance can mean an optical film that is not separately processed after manufacturing.

[0051] That is, in the formula (2), the initial average transmittance (T0) of the optical film in the wavelength range of 800 nm to 1000 nm may be 30% or more, 40% or more, 45% or more, 60% or less, 58% or less, 30% or more and 60% or less, 40% or more and 60% or less, 45% or more and 60% or less, 30% or more and 58% or less, 40% or more and 58% or less, 45% or more and 58% or less.

[0052] By having the initial average transmittance of the optical film be 30% or more and 60% or less, an optical film excellent in light absorption rate for near-infrared light in the wavelength range of 750 nm or more and 1500 nm or less can be provided, which is suitable for applications such as Augmented Reality (AR).

[0053] In the formula 2, after being exposed to the high temperature and high humidity conditions, the average transmittance (T2) of the optical film in the wavelength range of 800 nm to 1000 nm can mean the average transmittance in the wavelength range of 800 nm or more and 1000 nm or less measured after evaluating the optical film of the embodiment under the conditions of 85 °C and 85% for 72 hours. At this time, the maximum value is 0.10 to 1.00 W / cm 2 or the light amount of 0.68 W / cm 2 can be applied, and a QUV device (Q-Lab Corporation) etc. can be used.

[0054] The coating layer is formed from a composition for forming a coating layer of an embodiment described later.

[0055] The type of the base material is not particularly limited, and those known in the related technical field can be used. For example, base materials such as glass, PET (polyethylene terephthalate), TAC (triacetyl cellulose), PC (poluycarbonate), and COP (cyclo-olefin polymer) can be used.

[0056] The optical film of the embodiment contains a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less in the coating layer together with the vinyl cyanide compound - aromatic compound copolymer. Due to the excellent oxidation stability of the vinyl cyanide compound - aromatic compound copolymer against heat and light, the generation of reactive species that affect the stability of the dye is small, and the stability of the dye is enhanced. Thus, even when used under harsh conditions, it has excellent light resistance and moisture resistance, and can achieve excellent light absorption in the wavelength range of 750 nm or more and 1500 nm or less.

[0057] The coating layer of the above-described embodiment can contain a vinyl cyanide compound-aromatic vinyl compound copolymer.

[0058] When containing a vinyl cyanide compound-aromatic vinyl compound copolymer, excellent light resistance can be achieved as compared with the case of containing a UV-curable polymer resin such as an acrylic resin, a thermosetting resin such as a urethane resin or an epoxy resin, or a thermoplastic resin such as an acrylic resin.

[0059] Specifically, when a UV-curable polymer resin or a thermosetting resin is used, the light resistance is weak, and when used together with a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less, the light absorption performance of the dye may be reduced.

[0060] By including a vinyl cyanide compound-aromatic vinyl compound copolymer in the coating layer of the above-described embodiment, excellent light resistance and moisture resistance are realized due to the excellent oxidation stability of the vinyl cyanide compound-aromatic vinyl compound copolymer against heat and light, and thereby excellent light absorption performance of the dye can be realized even under harsh conditions.

[0061] In the above-described embodiment, the vinyl cyanide compound-aromatic vinyl compound copolymer may have a weight average molecular weight of 10,000 g / mol or more and 200,000 g / mol or less.

[0062] Unless otherwise specified, the "copolymer" can include a random copolymer, a block copolymer, and a graft copolymer.

[0063] Specifically, the vinyl cyanide compound-aromatic vinyl compound copolymer may have a weight average molecular weight of 10,000 g / mol or more, 50,000 g / mol or more, 80,000 g / mol or more, 100,000 g / mol or more, or 200,000 g / mol or less, 150,000 g / mol or less, 120,000 g / mol or less, or 10,000 g / mol or more and 200,000 g / mol or less, 10,000 g / mol or more and 150,000 g / mol or less, 10,000 g / mol or more and 120,000 g / mol or less, 50,000 g / mol or more and 200,000 g / mol or less, 50,000 g / mol or more and 150,000 g / mol or less, 50,000 g / mol or more and 120,000 g / mol or less, 80,000 g / mol or more and 200,000 g / mol or less, 80,000 g / mol or more and 150,000 g / mol or less, 80,000 g / mol or more and 120,000 g / mol or less, 100,000 g / mol or more and 200,000 g / mol or less, 100,000 g / mol or more and 150,000 g / mol or less, 100,000 g / mol or more and 120,000 g / mol or less.

[0064] In the above embodiment, when the weight average molecular weight of the vinyl cyanide compound-aromatic vinyl compound copolymer is 10,000 g / mol or more and 200,000 g / mol or less, due to the fluid characteristics during the formation of the coating liquid, it has excellent leveling and wetting properties, can form a uniform coating film, and at the same time, can achieve excellent light resistance properties.

[0065] When the weight average molecular weight of the vinyl cyanide compound-aromatic vinyl compound copolymer exceeds 200,000 g / mol, the viscosity of the coating liquid becomes high and a uniform coating film cannot be formed. When the weight average molecular weight is less than 10,000 g / mol, problems may occur such as a decrease in the heat stability of the resin and a deterioration of the light resistance properties.

[0066] In the above-described embodiment, the vinyl cyanide compound-aromatic vinyl compound copolymer may contain 10 parts by weight or more and 50 parts by weight or less of repeating units derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer.

[0067] The vinyl cyanide compound-aromatic vinyl compound copolymer may be a copolymer containing a vinyl cyanide compound and an aromatic vinyl compound as monomers, or may further contain additional monomers other than the vinyl cyanide compound and the aromatic vinyl compound.

[0068] The copolymer may include a random copolymer, a block copolymer, and a graft copolymer.

[0069] By adjusting the weight ratio between the monomers used in the production of the vinyl cyanide compound-aromatic vinyl compound copolymer, the content of the repeating units derived from the vinyl cyanide compound contained in the vinyl cyanide compound-aromatic vinyl compound copolymer can be adjusted.

[0070] Specifically, the vinyl cyanide compound-aromatic vinyl compound copolymer may contain 10 parts by weight or more, 15 parts by weight or more, 17 parts by weight or more, 50 parts by weight or less, 40 parts by weight or less, 30 parts by weight or less, or 10 parts by weight or more and 50 parts by weight or less, 10 parts by weight or more and 40 parts by weight or less, 10 parts by weight or more and 30 parts by weight or less, 15 parts by weight or more and 50 parts by weight or less, 15 parts by weight or more and 40 parts by weight or less, 15 parts by weight or more and 30 parts by weight or less, 17 parts by weight or more and 50 parts by weight or less, 17 parts by weight or more and 40 parts by weight or less, 17 parts by weight or more and 30 parts by weight or less of the repeating units derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer.

[0071] That is, based on 100 parts by weight of the total monomers used in the production of the vinyl cyanide compound - aromatic vinyl compound copolymer, the vinyl cyanide compound is 10 parts by weight or more, 15 parts by weight or more, 17 parts by weight or more, 50 parts by weight or less, 40 parts by weight or less, 30 parts by weight or less, or 10 parts by weight or more and 50 parts by weight or less, 10 parts by weight or more and 40 parts by weight or less, 10 parts by weight or more and 30 parts by weight or less, 15 parts by weight or more and 50 parts by weight or less, 15 parts by weight or more and 40 parts by weight or less, 15 parts by weight or more and 30 parts by weight or less, 17 parts by weight or more and 50 parts by weight or less, 17 parts by weight or more and 40 parts by weight or less, 17 parts by weight or more and 30 parts by weight or less.

[0072] When the vinyl cyanide compound - aromatic vinyl compound copolymer contains 10 parts by weight or more and 50 parts by weight or less of the repeating unit derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, the stability of the vinyl cyanide compound - aromatic vinyl compound copolymer against light and the gas permeability are improved, and excellent light stability and heat stability can be achieved.

[0073] When the vinyl cyanide compound - aromatic vinyl compound copolymer contains less than 10 parts by weight of the repeating unit derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, the stability of the vinyl cyanide compound - aromatic vinyl compound copolymer against light and the gas permeability decrease, and the light stability becomes poor. When it contains more than 50 parts by weight, the stability against heat decreases, and the heat stability may become poor.

[0074] On the other hand, in the above - mentioned embodiment, the vinyl cyanide compound - aromatic vinyl compound copolymer can contain 50 parts by weight or more and 90 parts by weight or less of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer.

[0075] By adjusting the weight ratio between the monomers used in the production of the vinyl cyanide compound - aromatic vinyl compound copolymer, the content of the repeating unit derived from the aromatic vinyl compound contained in the vinyl cyanide compound - aromatic vinyl compound copolymer can be adjusted.

[0076] Specifically, the vinyl cyanide compound - aromatic vinyl compound copolymer contains 50 parts by weight or more, 60 parts by weight or more, 70 parts by weight or more, 90 parts by weight or less, 85 parts by weight or less, 83 parts by weight or less, or 50 parts by weight or more and 90 parts by weight or less, 50 parts by weight or more and 85 parts by weight or less, 50 parts by weight or more and 83 parts by weight or less, 60 parts by weight or more and 90 parts by weight or less, 60 parts by weight or more and 85 parts by weight or less, 60 parts by weight or more and 83 parts by weight or less, 70 parts by weight or more and 90 parts by weight or less, 70 parts by weight or more and 85 parts by weight or less, 70 parts by weight or more and 83 parts by weight or less of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer.

[0077] That is, the aromatic vinyl compound is contained in an amount of 50 parts by weight or more, 60 parts by weight or more, 70 parts by weight or more, 90 parts by weight or less, 85 parts by weight or less, 83 parts by weight or less, or 50 parts by weight or more and 90 parts by weight or less, 50 parts by weight or more and 85 parts by weight or less, 50 parts by weight or more and 83 parts by weight or less, 60 parts by weight or more and 90 parts by weight or less, 60 parts by weight or more and 85 parts by weight or less, 60 parts by weight or more and 83 parts by weight or less, 70 parts by weight or more and 90 parts by weight or less, 70 parts by weight or more and 85 parts by weight or less, 70 parts by weight or more and 83 parts by weight or less with respect to 100 parts by weight of the total monomers used in the production of the vinyl cyanide compound - aromatic vinyl compound copolymer.

[0078] When the vinyl cyanide compound - aromatic vinyl compound copolymer contains 50 parts by weight or more and 90 parts by weight or less of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, good thermal stability and excellent mechanical properties of the vinyl cyanide compound - aromatic vinyl compound copolymer are realized, and not only can the finally produced optical film achieve excellent heat resistance stability, but also good scratch resistance can be realized.

[0079] When the vinyl cyanide compound - aromatic vinyl compound copolymer contains less than 50 parts by weight of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, the stability due to heat is poor and the light resistance or heat resistance stability decreases. When it contains more than 90 parts by weight, the light stability and gas permeability of the vinyl cyanide compound - aromatic vinyl compound copolymer decrease and the light resistance stability may become poor.

[0080] Further, the vinyl cyanide compound - aromatic vinyl compound copolymer can contain 110 parts by weight or more and 500 parts by weight or less of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the repeating unit derived from the vinyl cyanide compound.

[0081] Specifically, the vinyl cyanide compound - aromatic vinyl compound copolymer can contain 110 parts by weight or more, 150 parts by weight or more, 200 parts by weight or more, 500 parts by weight or less, 450 parts by weight or less, 110 parts by weight or more and 500 parts by weight or less, 150 parts by weight or more and 500 parts by weight or less, 200 parts by weight or more and 500 parts by weight or less, 110 parts by weight or more and 450 parts by weight or less, 150 parts by weight or more and 450 parts by weight or less, 200 parts by weight or more and 450 parts by weight or less of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the repeating unit derived from the vinyl cyanide compound.

[0082] The vinyl cyanide compound is not greatly restricted. For example, it can contain one or more compounds selected from the group consisting of acrylonitrile, methacrylonitrile, ethyl acrylonitrile and isopropyl acrylonitrile. For example, the vinyl cyanide compound can contain acrylonitrile.

[0083] Also, the aromatic vinyl compound is not greatly restricted. For example, it can contain one or more compounds selected from the group consisting of styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, and p-tert-butylstyrene. For example, the aromatic vinyl compound can contain styrene or α-methylstyrene.

[0084] On the other hand, the coating layer of the one embodiment can further contain a polymer resin other than the vinyl cyanide compound-aromatic vinyl compound copolymer.

[0085] The coating layer can contain 90 parts by weight or more of the vinyl cyanide compound-aromatic vinyl compound copolymer with respect to 100 parts by weight in total of the polymer resins contained in the coating layer.

[0086] Specifically, the coating layer can contain 90 parts by weight or more, 95 parts by weight or more, 99 parts by weight or more, 99.9 parts by weight or more, 100 parts by weight or less, or 90 parts by weight or more and 100 parts by weight or less, 95 parts by weight or more and 100 parts by weight or less, 99 parts by weight or more and 100 parts by weight or less, 99.9 parts by weight or more and 100 parts by weight or less of the vinyl cyanide compound-aromatic vinyl compound copolymer with respect to 100 parts by weight in total of the polymer resins contained in the coating layer. For example, the coating layer can contain only the vinyl cyanide compound-aromatic vinyl compound copolymer as the polymer resin.

[0087] By containing 90 parts by weight or more of the vinyl cyanide compound-aromatic vinyl compound copolymer with respect to 100 parts by weight in total of the polymer resins contained in the coating layer, the coating layer realizes excellent light resistance and moisture resistance. As a result, even under harsh conditions, hardly any reactive species that affect the stability of the dye by being excellent in the oxidation stability of the dye against heat and light are generated, and excellent light absorption performance can be realized.

[0088] When the coating layer contains less than 90 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer with respect to 100 parts by weight of the total polymer resin contained in the coating layer, the light absorption performance of the dye deteriorates, and the finally produced optical film is inferior in moisture resistance and light resistance and may have poor light absorption performance under harsh conditions.

[0089] In the above embodiment, the coating layer can contain a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less.

[0090] Since the coating layer contains a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less, it is excellent in light absorption rate for near-infrared rays in the wavelength region of 750 nm or more and 1500 nm or less, and an optical film suitable for application to augmented reality (AR) etc. can be provided.

[0091] The type of the dye with the maximum absorption wavelength of 750 nm or more and 1500 nm or less is not particularly limited, and it can be appropriately selected and used from among the compounds known to perform the said function. Examples of the usable dyes include sulfonium derivatives of ceramidone, new methylene blue, thioerythrosine triethylammonium, 6-acetylamino-2-methylceramidonin, eosin, erythrosine, rose bengal, thionine, basic yellow, Pinacyanol chloride, rhodamine 6G, gallocyanine, ethyl violet, Victoria blue R, Celestine blue, Quinaldine Red, crystal violet, Brilliant Green, Astrazon orange G, darrow red, pyronin Y, basic red 29, pyrylium iodide, Safranin O, cyanine, methylene blue, Azure A, or a combination of two or more selected from these.

[0092] Specifically, the dye with the maximum absorption wavelength of 750 nm or more and 1500 nm or less can include cyanine dyes.

[0093] In the above-described embodiment, the coating layer can contain 0.1 to 3 parts by weight of a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less with respect to a total of 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer.

[0094] Specifically, the coating layer can contain 0.1 part by weight or more, 0.5 part by weight or more, 3 parts by weight or less, 2 parts by weight or less, 1 part by weight or less, or 0.1 to 3 parts by weight, 0.1 to 2 parts by weight, 0.1 to 1 part by weight, 0.5 to 3 parts by weight, 0.5 to 2 parts by weight, 0.5 to 1 part by weight of a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less with respect to a total of 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer.

[0095] When the coating layer contains 0.1 to 3 parts by weight of a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less with respect to a total of 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, light in the region of 750 nm or more and 1500 nm entering from the external environment can be absorbed, and the eye-tracking performance of the AR / VR device can be improved.

[0096] When the coating layer contains less than 0.1 part by weight of a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less with respect to a total of 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, light cannot be sufficiently absorbed, resulting in a decrease in eye-tracking performance. When it contains more than 3 parts by weight, problems such as a decrease in visible light transmittance or an increase in the color value of the optical film and a decrease in optical properties may occur.

[0097] Also, in one example, the coating layer can further contain other additives. Examples of other additives that can be used include, for example, defoamers.

[0098] In one example, as the antifoaming agent, a silicone-based reactive additive can be used, and commercially available products such as Tego Rad 2500 can be used.

[0099] The content of the additives, such as the antifoaming agent and the plasticizer, can be appropriately adjusted at a level that does not interfere with the functions of the optical film.

[0100] The coating layer can contain the other additives in the range of 5 to 50 parts by weight based on 100 parts by weight of the vinyl cyanide compound-aromatic compound copolymer. Specifically, the lower limit of the content of the other additives may be, for example, 10 parts by weight or more, 15 parts by weight or more, 20 parts by weight or more, 25 parts by weight or more, 30 parts by weight or more, 35 parts by weight or more, 40 parts by weight or more, or 45 parts by weight or more, and the upper limit may be, for example, 45 parts by weight or less, 40 parts by weight or less, 35 parts by weight or less, 30 parts by weight or less, 25 parts by weight or less, 20 parts by weight or less, 15 parts by weight or less, or 10 parts by weight or less. When the above range is satisfied, the effects of using the additives can be appropriately ensured without interfering with the properties required for the coating layer.

[0101] Specifically, the example of the method for manufacturing the optical film of the above embodiment is not greatly limited. For example, a manufacturing method including a step of applying the composition for forming the coating layer to a substrate to form a coating film (step 1) and a step of drying the coating film (step 2) can be used.

[0102] The step 1 is a step of applying the composition for forming the coating layer described above to a substrate to form a coating film. The method of applying the composition for forming the coating layer to the substrate is not particularly limited.

[0103] As described above, the composition for forming the coating layer can contain an organic solvent. The composition for forming the coating layer can contain a solid content in an amount that gives an appropriate viscosity in consideration of processability such as coatability during the film formation process. For example, the composition for forming the coating layer can contain a solvent such that the concentration of the total solid content of the components contained in the composition is 1 to 70% by weight. Specifically, the solvent can be contained such that the concentration of the total solid content of the components contained in the composition is 2% by weight or more, 5% by weight or more, 10% by weight or more, or 20% by weight or more and 65% by weight or less, 60% by weight or less, 55% by weight or less, or 50% by weight or less.

[0104] In addition, as described above, the composition for forming the coating layer can additionally contain other components in addition to the organic solvent. As non-limiting examples, additives that can improve the thickness uniformity and surface smoothness, or improve the adhesion to the substrate, or change the dielectric constant or conductivity, or increase the density can be additionally contained. Examples of such additives include surfactants, silane-based compounds, dielectrics, or crosslinkable compounds.

[0105] The step 2 is a step of drying the coating film formed by applying the composition for forming the coating layer to a substrate.

[0106] The drying step of the coating film is carried out by heating means such as a hot plate, a hot air circulation furnace, or an infrared furnace, and can be carried out at a temperature of 50°C or higher and 150°C or lower, or 50°C or higher and 100°C or lower.

[0107] The thickness of the optical film of the above embodiment is not greatly limited, but can be freely adjusted, for example, within the range of 0.01 μm or more and 1000 μm or less. When the thickness of the optical film increases or decreases by a specific value, the physical properties measured with the optical film can also change by a certain value.

[0108] In the above embodiment, the thickness of the coating layer is not greatly limited, but for example, it can be freely adjusted within the range of 0.005 μm or more and 1000 μm or less. More specifically, the thickness of the coating layer is 0.005 μm or more, 0.01 μm or more, 0.1 μm or more, 1 μm or more, 3 μm or more, or 1000 μm or less, 20 μm or less, 15 μm or less, or 0.01 μm or more and 1000 μm or less, 0.01 μm or more and 20 μm or less, 0.01 μm or more and 15 μm or less, 0.1 μm or more and 1000 μm or less, 0.1 μm or more and 20 μm or less, 0.1 μm or more and 15 μm or less, 1 μm or more and 1000 μm or less, 1 μm or more and 20 μm or less, 1 μm or more and 15 μm or less, 3 μm or more and 1000 μm or less, 3 μm or more and 20 μm or less, 3 μm or more and 15 μm or less. When the thickness of the coating layer increases or decreases by a specific value, the physical properties measured with the optical film can also change by a certain value.

[0109] The thickness of the base material is also not greatly limited. For example, it may be in the range of 0.01 μm or more and 1000 μm or less, or 1 μm or more, 3 μm or more, or 1000 μm or less, 500 μm or less, 100 μm or less.

[0110] On the other hand, the optical film may have an average transmittance of 85% or more and 95% or less for wavelengths from 400 nm to 500 nm.

[0111] The average transmittance is a value measured for an optical film with a thickness of 20 μm or more and 250 μm or less. Although the specific measurement method is not greatly restricted, for example, it can be measured using a spectrophotometer such as Shimadzu's SolidSpec-3700.

[0112] Specifically, the optical film may have an average transmittance of 85% or more, 89% or more, 95% or less, 90% or less, 85% or more and 95% or less, 85% or more and 90% or less, 89% or more and 95% or less, 89% or more and 90% or less for wavelengths from 400 nm to 500 nm.

[0113] By having an average transmittance of 85% or more and 95% or less with respect to wavelengths of 400 nm or more and 500 nm or less, excellent visibility can be achieved.

[0114] Dyes having a maximum absorption wavelength of 750 nm or more and 1500 nm or less are vulnerable to light stability. Conventionally, in the case of optical films containing such dyes, there has been a problem that the light resistance decreases and the light absorption performance of the dyes deteriorates.

[0115] Therefore, the present inventors have conducted research on a composition for forming a coating layer that is excellent in light resistance and moisture resistance even when used under harsh conditions and can achieve excellent light absorption in the wavelength range of 750 nm or more and 1500 nm or less. In the case of a composition containing a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less together with the vinyl cyanide compound-aromatic compound copolymer, the vinyl cyanide compound-aromatic compound copolymer is excellent in oxidation stability against heat and light, and the generation of reactive species that affect the stability of the dye is small. By enhancing the stability of the dye, it has been confirmed that the finally produced optical film is excellent in light resistance and moisture resistance even when used under harsh conditions and can achieve excellent light absorption in the wavelength range of 750 nm or more and 1500 nm or less, and thus the invention has been completed.

[0116] On the other hand, the optical film may further include a metal oxide layer formed on the other surface of the base material.

[0117] The metal oxide layer may include an oxide of any one metal selected from the group consisting of indium, zinc, tin, aluminum, gallium, thallium, titanium, zirconium, hafnium, cesium, antimony, vanadium, niobium, tantalum, silicon, and germanium, or a composite oxide of two or more metals selected from the above metals.

[0118] For example, the metal oxide layer can include one or more metal oxides selected from the group consisting of indium tin oxide (ITO), indium zinc oxide (IZO), zinc tin oxide (ZTO), aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), and antimony-doped tin oxide (ATO).

[0119] The method for forming the metal oxide layer is not particularly limited. For example, a film formation method by a dry process such as sputtering, vacuum evaporation, CVD (Chemical Vapor Deposition), or electron beam evaporation can be applied.

[0120] The thickness of the metal oxide layer is not particularly limited and can be controlled to an appropriate thickness in consideration of the desired durability and adhesion. For example, the thickness of each metal oxide layer can be controlled within a range of about 1 nm to 100 nm, or about 3 nm to 45 nm. In one example, the thickness of the metal oxide layer may be about 40 nm or less, 35 nm or less, 30 nm or less, 25 nm or less, or 20 nm or less.

[0121] On the other hand, the optical film of the embodiment can include an adhesive layer formed on the coating layer. That is, the optical film of the embodiment can include a laminated structure in which a metal oxide layer, a substrate, a coating layer, and an adhesive layer are laminated in this order.

[0122] The adhesive layer is a layer that is applied and cured between the layers of the optical film to adhere the layers to each other, and either one of an optical clear adhesive (OCA) and an optical clear resin (OCR) can be used.

[0123] On the other hand, the optical film of the embodiment can further include a metal oxide layer and a substrate on the other side of the adhesive layer. That is, the optical film of the embodiment can include a laminated structure in which a metal oxide layer, a substrate, a coating layer, an adhesive layer, a substrate, and a metal oxide layer are laminated in this order. In the optical film, each metal oxide layer and each substrate may be the same or different independently of each other.

[0124] In addition, the optical film of the above embodiment can further include a cover member on the other surface of the adhesive layer. That is, the optical film of the above embodiment can include a laminated structure in which a metal oxide layer, a base material, a coating layer, an adhesive layer, and a cover member are laminated in this order.

[0125] Furthermore, the optical film of the above embodiment can further include other layers between or above and below the illustrated laminated structure. Also in this case, the optical film is excellent in light resistance and moisture resistance and can achieve excellent light absorption performance even when exposed to harsh conditions.

[0126] The cover member is made of a plastic material, a metal material, or a glass material.

[0127] According to another embodiment of the invention, a composition for forming a coating layer is provided, which contains a vinyl cyanide compound-aromatic compound copolymer and a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less. The vinyl cyanide compound-aromatic vinyl compound copolymer has a weight average molecular weight of 10,000 g / mol or more and 200,000 g / mol or less, and the vinyl cyanide compound-aromatic vinyl compound copolymer contains 10 parts by weight or more and 50 parts by weight or less of repeating units derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer.

[0128] The coating layer of the optical film of the above-described embodiment is formed from the composition for forming a coating layer. The description of the vinyl cyanide compound-aromatic compound copolymer and the dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less includes all the above-described contents.

[0129] The composition for forming a coating layer of the above embodiment can contain a vinyl cyanide compound-aromatic vinyl compound copolymer.

[0130] When a vinyl cyanide compound - aromatic vinyl compound copolymer is included, excellent light resistance can be achieved as compared with the case of including a UV - curable polymer resin such as an acrylate resin or an epoxy resin, or a thermosetting resin such as a urethane resin or an epoxy resin.

[0131] Specifically, the UV - curable polymer resin or the thermosetting resin has poor light resistance, and when used together with a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less, the light absorption performance of the dye may decrease.

[0132] The composition for forming a coating layer of the above - mentioned embodiment includes a vinyl cyanide compound - aromatic vinyl compound copolymer, and due to the excellent oxidation stability of the vinyl cyanide compound - aromatic vinyl compound copolymer against heat and light, excellent light resistance and moisture resistance are realized, and thereby excellent light absorption performance of the dye can be realized even under severe conditions.

[0133] In the above - mentioned embodiment, the vinyl cyanide compound - aromatic vinyl compound copolymer may have a weight - average molecular weight of 10,000 g / mol or more and 200,000 g / mol or less.

[0134] The "copolymer" can include a random copolymer, a block copolymer, and a graft copolymer unless otherwise specified.

[0135] Specifically, the vinyl cyanide compound-aromatic vinyl compound copolymer may have a weight average molecular weight of 10,000 g / mol or more, 50,000 g / mol or more, 80,000 g / mol or more, 100,000 g / mol or more, or 200,000 g / mol or less, 150,000 g / mol or less, 120,000 g / mol or less, or 10,000 g / mol or more and 200,000 g / mol or less, 10,000 g / mol or more and 150,000 g / mol or less, 10,000 g / mol or more and 120,000 g / mol or less, 50,000 g / mol or more and 200,000 g / mol or less, 50,000 g / mol or more and 150,000 g / mol or less, 50,000 g / mol or more and 120,000 g / mol or less, 80,000 g / mol or more and 200,000 g / mol or less, 80,000 g / mol or more and 150,000 g / mol or less, 80,000 g / mol or more and 120,000 g / mol or less, 100,000 g / mol or more and 200,000 g / mol or less, 100,000 g / mol or more and 150,000 g / mol or less, 100,000 g / mol or more and 120,000 g / mol or less.

[0136] In the above embodiment, the vinyl cyanide compound-aromatic vinyl compound copolymer has a weight average molecular weight of 10,000 g / mol or more and 200,000 g / mol or less, so that due to the fluid characteristics during the formation of the coating liquid, it has excellent leveling and wetting properties and can form a uniform coating film, and at the same time, excellent light resistance properties can be realized.

[0137] When the weight average molecular weight of the vinyl cyanide compound-aromatic vinyl compound copolymer exceeds 200,000 g / mol, the viscosity of the coating liquid becomes high and a uniform coating film cannot be formed. When the weight average molecular weight is less than 10,000 g / mol, problems such as a decrease in the heat stability of the resin and a reduction in light resistance properties may occur.

[0138] In the above-described embodiment, the vinyl cyanide compound-aromatic vinyl compound copolymer may contain 10 to 50 parts by weight of the repeating unit derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer.

[0139] The vinyl cyanide compound-aromatic vinyl compound copolymer may be a copolymer containing a vinyl cyanide compound and an aromatic vinyl compound as monomers, or may further contain additional monomers other than the vinyl cyanide compound and the aromatic vinyl compound.

[0140] The copolymer may include a random copolymer, a block copolymer, and a graft copolymer.

[0141] By adjusting the weight ratio between the monomers used in the production of the vinyl cyanide compound-aromatic vinyl compound copolymer, the content of the repeating unit derived from the vinyl cyanide compound contained in the vinyl cyanide compound-aromatic vinyl compound copolymer can be adjusted.

[0142] Specifically, the vinyl cyanide compound-aromatic vinyl compound copolymer may contain 10 parts by weight or more, 15 parts by weight or more, 17 parts by weight or more, 50 parts by weight or less, 40 parts by weight or less, 30 parts by weight or less, or 10 to 50 parts by weight, 10 to 40 parts by weight, 10 to 30 parts by weight, 15 to 50 parts by weight, 15 to 40 parts by weight, 15 to 30 parts by weight, 17 to 50 parts by weight, 17 to 40 parts by weight, 17 to 30 parts by weight of the repeating unit derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer.

[0143] That is, based on 100 parts by weight of the total monomers used in the production of the vinyl cyanide compound - aromatic vinyl compound copolymer, the vinyl cyanide compound is 10 parts by weight or more, 15 parts by weight or more, 17 parts by weight or more, 50 parts by weight or less, 40 parts by weight or less, 30 parts by weight or less, or 10 parts by weight or more and 50 parts by weight or less, 10 parts by weight or more and 40 parts by weight or less, 10 parts by weight or more and 30 parts by weight or less, 15 parts by weight or more and 50 parts by weight or less, 15 parts by weight or more and 40 parts by weight or less, 15 parts by weight or more and 30 parts by weight or less, 17 parts by weight or more and 50 parts by weight or less, 17 parts by weight or more and 40 parts by weight or less, 17 parts by weight or more and 30 parts by weight or less.

[0144] When the vinyl cyanide compound - aromatic vinyl compound copolymer contains 10 parts by weight or more and 50 parts by weight or less of the repeating unit derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, the stability of the vinyl cyanide compound - aromatic vinyl compound copolymer against light and the gas permeability are improved, and excellent light stability and heat stability can be achieved.

[0145] When the vinyl cyanide compound - aromatic vinyl compound copolymer contains less than 10 parts by weight of the repeating unit derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, the stability of the vinyl cyanide compound - aromatic vinyl compound copolymer against light and the gas permeability decrease, resulting in poor light stability. When it contains more than 50 parts by weight, the stability against heat decreases, and the heat stability may become poor.

[0146] On the other hand, in the one embodiment, the vinyl cyanide compound - aromatic vinyl compound copolymer can contain 50 parts by weight or more and 90 parts by weight or less of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer.

[0147] By adjusting the weight ratio between the monomers used in the production of the vinyl cyanide compound - aromatic vinyl compound copolymer, the content of the repeating units derived from the aromatic vinyl compound contained in the vinyl cyanide compound - aromatic vinyl compound copolymer can be adjusted.

[0148] Specifically, the vinyl cyanide compound - aromatic vinyl compound copolymer contains 50 parts by weight or more, 60 parts by weight or more, 70 parts by weight or more, 90 parts by weight or less, 85 parts by weight or less, 83 parts by weight or less, or 50 parts by weight or more and 90 parts by weight or less, 50 parts by weight or more and 85 parts by weight or less, 50 parts by weight or more and 83 parts by weight or less, 60 parts by weight or more and 90 parts by weight or less, 60 parts by weight or more and 85 parts by weight or less, 60 parts by weight or more and 83 parts by weight or less, 70 parts by weight or more and 90 parts by weight or less, 70 parts by weight or more and 85 parts by weight or less, 70 parts by weight or more and 83 parts by weight or less of the repeating units derived from the aromatic vinyl compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer.

[0149] That is, the aromatic vinyl compound is contained in an amount of 50 parts by weight or more, 60 parts by weight or more, 70 parts by weight or more, 90 parts by weight or less, 85 parts by weight or less, 83 parts by weight or less, or 50 parts by weight or more and 90 parts by weight or less, 50 parts by weight or more and 85 parts by weight or less, 50 parts by weight or more and 83 parts by weight or less, 60 parts by weight or more and 90 parts by weight or less, 60 parts by weight or more and 85 parts by weight or less, 60 parts by weight or more and 83 parts by weight or less, 70 parts by weight or more and 90 parts by weight or less, 70 parts by weight or more and 85 parts by weight or less, 70 parts by weight or more and 83 parts by weight or less with respect to 100 parts by weight of the total monomers used in the production of the vinyl cyanide compound - aromatic vinyl compound copolymer.

[0150] When the vinyl cyanide compound - aromatic vinyl compound copolymer contains 50 parts by weight or more and 90 parts by weight or less of the repeating units derived from the aromatic vinyl compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, good thermal stability and excellent mechanical properties of the vinyl cyanide compound - aromatic vinyl compound copolymer are realized, and the finally produced optical film can realize not only excellent heat resistance stability but also good scratch resistance.

[0151] When the vinyl cyanide compound - aromatic vinyl compound copolymer contains less than 50 parts by weight of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, the stability by heat is poor and the light resistance or heat resistance stability decreases. When it contains more than 90 parts by weight, the light stability and gas permeability of the vinyl cyanide compound - aromatic vinyl compound copolymer decrease and the light resistance stability may become poor.

[0152] Further, the vinyl cyanide compound - aromatic vinyl compound copolymer can contain 110 parts by weight or more and 500 parts by weight or less of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the repeating unit derived from the vinyl cyanide compound.

[0153] Specifically, the vinyl cyanide compound - aromatic vinyl compound copolymer can contain 110 parts by weight or more, 150 parts by weight or more, 200 parts by weight or more, 500 parts by weight or less, 450 parts by weight or less, 110 parts by weight or more and 500 parts by weight or less, 150 parts by weight or more and 500 parts by weight or less, 200 parts by weight or more and 500 parts by weight or less, 110 parts by weight or more and 450 parts by weight or less, 150 parts by weight or more and 450 parts by weight or less, 200 parts by weight or more and 450 parts by weight or less of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the repeating unit derived from the vinyl cyanide compound.

[0154] By the vinyl cyanide compound - aromatic vinyl compound copolymer containing 110 parts by weight or more and 500 parts by weight or less of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the repeating unit derived from the vinyl cyanide compound, not only can good thermal stability and excellent mechanical properties of the vinyl cyanide compound - aromatic vinyl compound copolymer be realized, but also the finally produced optical film can realize excellent heat resistance stability and can realize good scratch resistance.

[0155] When the vinyl cyanide compound - aromatic vinyl compound copolymer contains less than 110 parts by weight of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the repeating unit derived from the vinyl cyanide compound, the stability to heat is poor and the light resistance or heat resistance stability decreases. When it contains more than 500 parts by weight, the stability of the vinyl cyanide compound - aromatic vinyl compound copolymer to light and the gas permeability decrease, and the light resistance stability may become poor.

[0156] The vinyl cyanide compound is not greatly restricted. For example, it can contain one or more compounds selected from the group consisting of acrylonitrile, methacrylonitrile, ethyl acrylonitrile, and isopropyl acrylonitrile. For example, the vinyl cyanide compound can contain acrylonitrile.

[0157] Also, the aromatic vinyl compound is not greatly restricted. For example, it can contain one or more compounds selected from the group consisting of styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, and p-tert-butylstyrene. For example, the aromatic vinyl compound can contain styrene or α-methylstyrene.

[0158] On the other hand, the composition for forming a coating layer of the one embodiment can further contain a polymer resin other than the vinyl cyanide compound - aromatic vinyl compound copolymer.

[0159] The composition for forming a coating layer can contain 90 parts by weight or more of the vinyl cyanide compound - aromatic vinyl compound copolymer with respect to 100 parts by weight in total of the polymer resins contained in the composition for forming a coating layer.

[0160] Specifically, the composition for forming the coating layer can contain 90 parts by weight or more, 95 parts by weight or more, 99 parts by weight or more, 99.9 parts by weight or more, 100 parts by weight or less, or 90 parts by weight or more and 100 parts by weight or less, 95 parts by weight or more and 100 parts by weight or less, 99 parts by weight or more and 100 parts by weight or less, 99.9 parts by weight or more and 100 parts by weight or less of the vinyl cyanide compound-aromatic vinyl compound copolymer with respect to a total of 100 parts by weight of the total polymer resins contained in the composition for forming the coating layer. For example, the composition for forming the coating layer can contain only the vinyl cyanide compound-aromatic vinyl compound copolymer as the polymer resin.

[0161] By containing 90 parts by weight or more of the vinyl cyanide compound-aromatic vinyl compound copolymer with respect to a total of 100 parts by weight of the total polymer resins contained in the composition for forming the coating layer, the composition for forming the coating layer realizes excellent light resistance and moisture resistance. As a result, even under harsh conditions, hardly any reactive species that affect the stability of the dye by being excellent in the oxidative stability of the dye against heat and light are generated, and excellent light absorption performance can be realized.

[0162] When the composition for forming the coating layer contains less than 90 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer with respect to a total of 100 parts by weight of the total polymer resins contained in the composition for forming the coating layer, the light absorption performance of the dye deteriorates, and the finally produced optical film is inferior in moisture resistance and light resistance and may have inferior light absorption performance under harsh conditions.

[0163] In the above embodiment, the composition for forming the coating layer can contain 10 parts by weight or more and 30 parts by weight or less of the vinyl cyanide compound-aromatic vinyl compound copolymer with respect to 100 parts by weight of the total composition for forming the coating layer.

[0164] Specifically, the composition for forming the coating layer can contain 10 parts by weight or more, 12 parts by weight or more, 30 parts by weight or less, 20 parts by weight or less, 15 parts by weight or less, or 10 parts by weight or more and 30 parts by weight or less, 12 parts by weight or more and 30 parts by weight or less, 10 parts by weight or more and 20 parts by weight or less, 12 parts by weight or more and 20 parts by weight or less, 10 parts by weight or more and 15 parts by weight or less, 12 parts by weight or more and 15 parts by weight or less of the vinyl cyanide compound - aromatic vinyl compound copolymer with respect to 100 parts by weight of the total composition for forming the coating layer.

[0165] In the above embodiment, the composition for forming the coating layer can contain a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less.

[0166] Since the composition for forming the coating layer contains a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less, an optical film excellent in the light absorption rate for near-infrared rays in the wavelength region of 750 nm or more and 1500 nm or less can be provided, which is suitable for applications to augmented reality (AR) and the like.

[0167] The type of the dye with the maximum absorption wavelength of 750 nm or more and 1500 nm or less is not particularly limited, and it can be appropriately selected from among the compounds known to perform the said function and used. Examples of the dyes that can be used include, for example, sulfonium derivatives of ceramidonin, new methylene blue, thioerythrosine triethylammonium, 6-acetylamino-2-methylceramidonin, eosin, erythrosine, rose bengal, thionine, basic yellow, Pinacyanol chloride, rhodamine 6G, gallocyanine, ethyl violet, Victoria blue R, Celestine blue, Quinaldine Red, crystal violet, Brilliant Green, Astrazon orange G, darrow red, pyronin Y, basic red 29, pyrylium iodide, Safranin O, cyanine, methylene blue, Azure A, or a combination of two or more selected from these.

[0168] Specifically, the dye with the maximum absorption wavelength of 750 nm or more and 1500 nm or less can include cyanine dyes.

[0169] In the above-described embodiment, the composition for forming the coating layer may contain 0.1 part by weight or more and 3 parts by weight or less of a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less with respect to a total of 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer.

[0170] Specifically, the composition for forming the coating layer may contain 0.1 part by weight or more, 0.5 part by weight or more, 3 parts by weight or less, 2 parts by weight or less, 1 part by weight or less, or 0.1 part by weight or more and 3 parts by weight or less, 0.1 part by weight or more and 2 parts by weight or less, 0.1 part by weight or more and 1 part by weight or less, 0.5 part by weight or more and 3 parts by weight or less, 0.5 part by weight or more and 2 parts by weight or less, 0.5 part by weight or more and 1 part by weight or less of a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less with respect to a total of 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer.

[0171] When the composition for forming the coating layer contains 0.1 part by weight or more and 3 parts by weight or less of a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less with respect to a total of 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer, light in the range of 750 nm or more and 1500 nm entering from the external environment can be absorbed, and the line-of-sight tracking performance of an electronic device including the optical film, for example, an AR / VR device, can be improved.

[0172] When the composition for forming the coating layer contains less than 0.1 part by weight of a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less with respect to a total of 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer, light cannot be sufficiently absorbed, resulting in a decrease in line-of-sight tracking performance. When the content exceeds 3 parts by weight, problems such as a decrease in visible light transmittance or an increase in the color value of the optical film and a deterioration in optical properties may occur.

[0173] On the other hand, the composition for forming the coating layer may further contain a solvent.

[0174] The solvent may be an organic solvent. For example, ketones, alcohols, acetates, and ethers, or a mixture of two or more of these can be used as the organic solvent, but it is not limited thereto.

[0175] Specific examples of such organic solvents include ketones such as methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, or isobutyl ketone; alcohols such as methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, or t-butanol; acetates such as ethyl acetate, i-propyl acetate, or polyethylene glycol monomethyl ether acetate; ethers such as tetrahydrofuran or propylene glycol monomethyl ether; toluene, xylene, ethylbenzene, cumene, and tetralin, or a mixture of two or more of these.

[0176] The organic solvent is added at the time of mixing each component contained in the composition for forming the coating layer, or is added in a state where each component is dispersed or mixed in the organic solvent and is contained in the composition for forming the coating layer.

[0177] For example, the composition for forming the coating layer can contain a solvent such that the concentration of the total solid content of the components contained in the composition is 1 to 70% by weight. Specifically, the solvent can be contained such that the concentration of the total solid content of the components contained in the composition is 2% by weight or more, 5% by weight or more, 10% by weight or more, or 20% by weight or more and 65% by weight or less, 60% by weight or less, 55% by weight or less, or 50% by weight or less. If the content of the solvent in the composition is excessively small, the fluidity of the composition may decrease, and defects such as streaks may occur in the finally produced film. Also, when the solvent is added in excess, the solid content decreases, and coating and film formation are not sufficient, resulting in a decrease in the physical properties and surface characteristics of the optical film, and defects may occur during the drying and curing processes.

[0178] Also, in the above example, the composition for forming the coating layer can further contain other additives. Examples of other additives that can be used include defoamers.

[0179] In one example, as the defoamer, silicone-based reactive additives can be used, and commercially available products such as Tego Rad 2500 can be used.

[0180] The content of the additives, for example, defoamers and plasticizers, can be appropriately adjusted at a level that does not interfere with the functions of the optical film.

[0181] The composition for forming the coating layer can contain the other additives in the range of 5 to 50 parts by weight based on 100 parts by weight of the vinyl cyanide compound - aromatic compound copolymer. Specifically, the lower limit of the content of the other additives can be, for example, 10 parts by weight or more, 15 parts by weight or more, 20 parts by weight or more, 25 parts by weight or more, 30 parts by weight or more, 35 parts by weight or more, 40 parts by weight or more, or 45 parts by weight or more, and the upper limit can be, for example, 45 parts by weight or less, 40 parts by weight or less, 35 parts by weight or less, 30 parts by weight or less, 25 parts by weight or less, 20 parts by weight or less, 15 parts by weight or less, or 10 parts by weight or less. When the above range is satisfied, the effects of using the additives can be appropriately ensured without interfering with the properties required for the composition for forming the coating layer.

[0182] On the other hand, according to another embodiment of the invention, an electronic device including the optical film can be provided.

[0183] The description of the optical film includes all the above-mentioned contents.

[0184] The electronic device can include a camera device unit that acquires an iris image, a light source in the infrared region, and an optical film that blocks the wavelength band of the light source in the infrared region and other external light.

[0185] The optical film can block the wavelength band of the light source in the infrared region and other external light, and mainly transmit only the light in the near-infrared band projected in the infrared region.

[0186] Accordingly, according to the optical film, by blocking the near-infrared region of a specific band of the external light source, the influence of the external light source can be minimized.

[0187] The use of the electronic device is not particularly limited. For example, it can be used in applications that are likely to be exposed to high temperature / high humidity conditions, specifically, smart devices such as mobile devices, components of wearable displays, or automotive components (e.g., head up display). More specifically, the electronic device can be suitable for application to Augmented Reality (AR).

Effect of the Invention

[0188] According to the present invention, there can be provided an optical film, a composition for forming a coating layer, and an electronic device, which are excellent in light absorption performance with respect to near-infrared light having a wavelength of 750 nm or more and 1500 nm or less, excellent in light resistance and moisture resistance, and capable of realizing excellent light absorption performance even when exposed to harsh conditions.

Mode for Carrying Out the Invention

[0189] The invention will be described in more detail with the following examples. However, the following examples merely illustrate the invention, and the content of the invention is not limited by the following examples.

[0190] <Examples 1 to 3 and Comparative Examples 1 to 4> Example 1 12.5 g of a vinyl cyanide compound - aromatic compound copolymer with a weight average molecular weight of 120,000 g / mol (manufacturer: LG Chem, styrene - acrylonitrile, content of repeating units derived from vinyl cyanide compound: 17% by weight), 0.12 g of a dye (NIR - absorbing cyanine - based dye with a maximum absorption wavelength of 865 nm), and 50 g of methyl ethyl ketone (MEK) and 37.5 g of toluene as solvents were added, and with light blocked, it was stirred with a paste mixer for about 30 minutes to produce a coating solution.

[0191] The coating solution was coated on a 60 - μm - thick TAC substrate using a meyer bar and dried within 2 minutes at 90°C to produce an optical film with a final thickness of 65 μm including a 5 - μm - thick coating layer.

[0192] Example 2 A coating solution and an optical film with a final thickness of 65 μm were produced in the same manner as in Example 1, except that 0.073 g of an NIR - absorbing dye (cyanine - based dye) with a maximum absorption wavelength of 930 nm was used instead of the NIR - absorbing dye (cyanine - based dye) with a maximum absorption wavelength of 865 nm.

[0193] Example 3 A coating solution and an optical film with a final thickness of 65 μm were produced in the same manner as in Example 1, except that 12.5 g of a vinyl cyanide compound - aromatic compound copolymer with a weight average molecular weight of 110,000 g / mol (manufacturer: LG Chem) was used instead of the vinyl cyanide compound - aromatic compound copolymer with a weight average molecular weight of 120,000 g / mol.

[0194] Comparative Example 1 Instead of the vinyl cyanide compound - aromatic compound copolymer with a weight average molecular weight of 120,000 g / mol, 12.5 g of polymethyl methacrylate (PMMA, Poly(Methyl Methacrylate), weight average molecular weight 100,000 g / mol, manufacturer: LG Chem) was used, and a coating solution and an optical film with a final thickness of 65 μm were produced in the same manner as in Example 1 except for this.

[0195] Comparative Example 2 25 g of pentaerythritol triacrylate (manufacturer: SK Entis) and 25 g of a 6-functional acrylate (product name: EB1290, manufacturer: SK Entis) were put in, 0.5 g of a dye (NIR absorbing dye with a maximum absorption wavelength of 865 nm), 2.5 g of a photoinitiator (Irgacure184), and 50 g of methyl ethyl ketone (MEK) as a solvent were added, and with light blocked, it was stirred with a paste mixer for about 30 minutes to produce a coating solution.

[0196] The said coating solution was coated on a 60-μm thick TAC substrate using a meyer bar, dried within 2 minutes at 60°C, and then cured with a light amount of 200 mJ / cm 2 to produce an optical film with a final thickness of 65 μm including a 5-μm thick coating layer.

[0197] Comparative Example 3 Instead of the vinyl cyanide compound - aromatic compound copolymer with a weight average molecular weight of 120,000 g / mol, 12.5 g of polystyrene (PS, weight average molecular weight 250,000 g / mol, manufacturer: LG Chem) was used, and a coating solution and an optical film with a final thickness of 65 μm were produced in the same manner as in Example 1 except for this.

[0198] Comparative Example 4 Instead of the NIR absorbing dye with a maximum absorption wavelength of 865 nm, 0.44 g of a NIR absorbing dye (cyanine-based dye) with a maximum absorption wavelength of 930 nm was used, and a coating solution and an optical film with a final thickness of 65 μm were produced in the same manner as in Example 1 except for this.

[0199] <Experimental Example> 1. Thickness For the optical films manufactured in the examples and comparative examples, the thickness of the entire optical film was measured using a digital micrometer (TESA, product name: μ-HITE).

[0200] 2. Transmittance For the optical films manufactured in the examples and comparative examples, the average transmittance for wavelengths from 400 nm to 500 nm and the average transmittance for wavelengths from 800 nm to 1000 nm were measured using a Shimadzu solidspec-3700.

[0201] Also, the maximum light transmittance was measured in a specific wavelength range from 750 nm to 1500 nm.

[0202] 3. Light resistance Regarding the optical films manufactured in the examples and comparative examples, after exposing them to a QUV device (Q-Lab) for 15 hours or more and 30 hours or less, the average transmittance was measured for the optical film of the above-described embodiment using a QUV device (Q-Lab) under the light quantity condition of 24 hours at 340 nm with a maximum value of 0.68 W / cm 2 After proceeding with the evaluation, the average transmittance for wavelengths from 800 nm to 1000 nm was measured by the above-described transmittance measurement method, and the change rate of the average transmittance before and after the light resistance test was measured by the following formula.

[0203] [Formula 1] Change rate of average transmittance = Average transmittance for wavelengths from 800 nm to 1000 nm after exposure to ultraviolet rays with a wavelength of 340 nm for 24 hours in a QUV device (Q-Lab) / Initial average transmittance for wavelengths from 800 nm to 1000 nm × 100.

[0204] 4. Damp heat reliability For the optical films produced in the examples and comparative examples, after exposing them in a thermo-hygrostat chamber (Jeiotech) at 85 °C and 85% for 72 hours, the average transmittance for wavelengths from 800 nm to 1000 nm was measured by the above-described transmittance measurement method, and the change rate of the average transmittance before and after the moisture resistance test was measured by the following formula.

[0205] [Formula 2] Change rate of average transmittance = (Average transmittance for wavelengths from 800 nm to 1000 nm after exposing at a temperature of 85 °C and a humidity of 85% for 72 hours - Initial average transmittance for wavelengths from 800 nm to 1000 nm) / Initial average transmittance for wavelengths from 800 nm to 1000 nm × 100.

[0206]

Table 1

[0207] <Examples 4 to 6 and Comparative Examples 5 to 8> Example 4 12.5 g of a vinyl cyanide compound - aromatic compound copolymer (weight average molecular weight 120,000 g / mol, manufacturing company: LG Chem), 0.12 g of a dye (NIR absorbing dye with a maximum absorption wavelength of 865 nm), and 50 g of methyl ethyl ketone (MEK) and 37.5 g of toluene as solvents were added, and while blocking light, it was stirred with a paste mixer for about 30 minutes to produce a coating solution.

[0208] The coating solution was coated on the other side of a PET substrate on which an indium - tin composite oxide (ITO) layer was formed using a meyer bar, and dried within 2 minutes at 90 °C to form a coating layer with a thickness of 5 μm.

[0209] A film - type OCA 25 - μm lamination adhesive layer was formed on the coating layer.

[0210] The PET substrate with the indium-tin composite oxide (ITO) layer [thickness: 150 nm] formed thereon was adhered onto the adhesive layer such that the PET substrate was in contact with the adhesive layer, thereby manufacturing an optical film with a total thickness of 131 μm.

[0211] Example 5 An optical film with a total thickness of 180 μm was manufactured in the same manner as in Example 1, except that glass (manufactured by Schott) with a thickness of 100 μm was adhered onto the adhesive layer.

[0212] Example 6 An optical film with a total thickness of 130 μm was manufactured in the same manner as in Example 1, except that 0.073 g of an NIR absorption dye with a maximum absorption wavelength of 930 nm was used instead of the NIR absorption dye with a maximum absorption wavelength of 865 nm.

[0213] Comparative Example 5 A coating solution and an optical film with a final thickness of 131 μm were manufactured in the same manner as in Example 1, except that 12.5 g of polymethyl methacrylate (PMMA, Poly(Methyl Methacrylate), weight average molecular weight 100,000 g / mol, manufactured by LG Chem) was used instead of the vinyl cyanide compound-aromatic compound copolymer.

[0214] Comparative Example 6 25 g of pentaerythritol triacrylate (manufactured by SK Entis) and 25 g of a 6-functional acrylate (product name: EB1290, manufactured by SK Entis) were placed, 0.5 g of a dye (NIR absorption dye with a maximum absorption wavelength of 865 nm), 2.5 g of a photoinitiator (Irgacure184), and 50 g of methyl ethyl ketone (MEK) as a solvent were added, and the mixture was stirred with a paste mixer for about 30 minutes in a light-blocked state to manufacture a coating solution.

[0215] The coating solution was coated on a TAC substrate with a thickness of 60 μm using a meyer bar, dried within 2 minutes at 60°C, and then cured with a light amount of 200 mJ / cm 2 to produce an optical film with a final thickness of 131 μm including a coating layer with a thickness of 5 μm.

[0216] <Experimental Example> 1. Thickness For the optical films produced in Examples 4 to 6 and Comparative Examples 5 to 6, the thickness of the entire optical film was measured using a digital micrometer.

[0217] 2. Transmittance For the optical films produced in Examples 4 to 6 and Comparative Examples 5 to 6, the average transmittance for wavelengths from 400 nm to 500 nm and the average transmittance for wavelengths from 800 nm to 1000 nm were measured using a solidspec-3700 from Shimadzu Corporation.

[0218] Also, the maximum absorption wavelength was measured in a specific wavelength range from 750 nm to 1500 nm.

[0219] 3. Light resistance For the optical films produced in Examples 4 to 6 and Comparative Examples 5 to 6, after evaluation was carried out under 1 SUN condition for 72 hours using a Q-SUN apparatus (Q LAB Corporation), the average transmittance for wavelengths from 800 nm to 1000 nm was measured by the above-described transmittance measurement method, and the change rate of the average transmittance before and after the light resistance test was measured by the following formula.

[0220] [Formula 1] Change rate of average transmittance = (Average transmittance after exposure to 1 SUN condition for 72 hours or less in a Q-SUN apparatus (Q LAB Corporation) - Initial average transmittance) / Initial average transmittance × 100.

[0221]

Table 2

[0222] As shown in Tables 1 and 2 above, the optical film of the example was excellent in light absorption performance for near-infrared rays with wavelengths of 750 nm or more and 1500 nm or less, excellent in light resistance and reliability in damp heat, and it was confirmed that excellent light absorption performance could be realized even when exposed to harsh conditions.

[0223] On the other hand, it was confirmed that the optical film of the comparative example was poor in light resistance and / or moisture resistance.

Claims

1. A base material and a coating layer formed on the base material, The coating layer contains a vinyl cyanide compound-aromatic compound copolymer and a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less, The vinyl cyanide compound-aromatic vinyl compound copolymer has a weight average molecular weight of 10,000 g / mol or more and 120,000 g / mol or less, The dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less contains a cyanine-based dye, The coating layer contains 0.1 parts by weight or more and 3 parts by weight or less of the dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less with respect to a total of 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer, Having an initial average transmittance (T0) of 30% or more in the wavelength region of 800 nm to 1000 nm, An optical film in which the change rate of the average transmittance calculated by the following formula 1 is 18% or less: [Formula 1] Change rate of average transmittance = [(After exposure with a light quantity of 0.68 to 1.00 W / cm2 for 24 to 30 hours in the wavelength region of 300 nm to 340 nm, the average transmittance (T1) of the optical film in the wavelength region of 800 nm to 1000 nm - the initial average transmittance (T0) of the optical film in the wavelength region of 800 nm to 1000 nm) / T0]×100.

2. The optical film according to claim 1, wherein the change rate of the average transmittance calculated by the following formula 2 is 10% or less: [Formula 2] Change rate of average transmittance =[(After exposure to high temperature and high humidity conditions, the average transmittance (T2) of the optical film in the wavelength region of 800 nm to 1000 nm - the initial average transmittance (T0) of the optical film in the wavelength region of 800 nm to 1000 nm) / T0]×100 At this time, exposure under high temperature and high humidity conditions means exposure for 50 to 100 hours under temperature conditions of 70°C to 100°C and humidity conditions of 70% to 90%.

3. The optical film according to claim 1, wherein the vinyl cyanide compound-aromatic vinyl compound copolymer contains 10 parts by weight or more and 50 parts by weight or less of repeating units derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound-aromatic vinyl compound copolymer.

4. The vinyl cyanide compound - aromatic vinyl compound copolymer contains 110 parts by weight or more and 500 parts by weight or less of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the repeating unit derived from the vinyl cyanide compound, and the optical film according to claim 1.

5. The thickness of the coating layer is 0.005 μm or more and 1000 μm, The optical film according to claim 1, wherein the thickness of the optical film is 0.01 μm or more and 1000 μm.

6. The optical film according to claim 1, further comprising a metal oxide layer formed on the other surface of the substrate.

7. The optical film according to claim 1 or 6, wherein the change rate of the average transmittance calculated by the formula 1 is 15% or less.

8. The metal oxide layer contains an oxide of any one metal selected from the group consisting of indium, zinc, tin, aluminum, gallium, thallium, titanium, zirconium, hafnium, cesium, antimony, vanadium, niobium, tantalum, silicon, and germanium, or a composite oxide of two or more metals selected from the above metals, and the optical film according to claim 6.

9. The metal oxide layer has a thickness of 1 nm to 100 nm, and the optical film according to claim 6.

10. An electronic device including the optical film according to claim 1.

11. It contains a vinyl cyanide compound - aromatic compound copolymer and a dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less, The vinyl cyanide compound - aromatic vinyl compound copolymer has a weight average molecular weight of 10,000 g / mol or more and 120,000 g / mol or less, The dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less contains a cyanine-based dye, The composition for forming a coating layer contains 0.1 parts by weight or more and 3 parts by weight or less of the dye having a maximum absorption wavelength of 750 nm or more and 1500 nm or less with respect to a total of 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, The vinyl cyanide compound - aromatic vinyl compound copolymer contains 10 parts by weight or more and 50 parts by weight or less of the repeating unit derived from the vinyl cyanide compound with respect to 100 parts by weight of the vinyl cyanide compound - aromatic vinyl compound copolymer, and the composition for forming a coating layer.

12. The vinyl cyanide compound - aromatic vinyl compound copolymer contains 110 parts by weight or more and 500 parts by weight or less of the repeating unit derived from the aromatic vinyl compound with respect to 100 parts by weight of the repeating unit derived from the vinyl cyanide compound, and is the composition for forming a coating layer according to claim 11.

Images