Laminated film and image display device comprising same

Abstract

The present invention relates to a laminated film and an image display device comprising same, the laminated film comprising: a hard coating layer; and a substrate, wherein the hard coating layer comprises a near-ultraviolet absorber and an ultraviolet photosensitizer, and the substrate comprises an ultraviolet blocking additive.

Description

Laminated film and image display device including the same

[0001] The present invention relates to a laminated film and an image display device including the same.

[0002] Recently, organic light emitting diodes (OLEDs) are widely used as display materials in various smart devices characterized by portability, including smartphones, tablet PCs, and various wearable devices.

[0003] Traditional OLED devices used polarizing films to prevent external light reflection. However, a growing number of OLED devices are opting for polarizing films to improve brightness or provide transparency. These devices, which do not use polarizing films, suffer from the deterioration of the OLED elements due to exposure to ultraviolet and near-ultraviolet light, shortening the display's lifespan.

[0004] Korean Patent Publication No. 10-2000-0042841 provides an agricultural film composition for blocking near-ultraviolet rays, but there is a problem in that the curing degree is reduced due to the ultraviolet additive when manufacturing a film by adding ultraviolet additives to the film and curing it using ultraviolet rays.

[0005] Accordingly, there is a need for the development of a laminated film and an image display device including the same that can secure sufficient substrate adhesion by maintaining the UV curing efficiency of the hard coating layer while preventing deterioration of OLED elements by shielding near-ultraviolet rays.

[0006] The present invention aims to provide a laminated film that can effectively block near-ultraviolet rays while maintaining transparency in the visible light range to prevent deterioration of OLED elements and maintain the ultraviolet curing efficiency of a hard coating layer, thereby ensuring sufficient substrate adhesion, in order to solve the above-described problems.

[0007] In addition, the present invention aims to provide a window having excellent light resistance characteristics, including the laminated film, and an image display device including the same.

[0008] However, the problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

[0009]

[0010] The present invention relates to a laminated film comprising a hard coating layer and a substrate, wherein the hard coating layer comprises a near-ultraviolet absorbent and an ultraviolet photosensitizer, and the substrate is a ultraviolet blocking substrate.

[0011] In the present invention, the transmittance at a wavelength of 380 nm of the above-described material may be 10% or less.

[0012] In the present invention, the substrate may include a UV blocking additive.

[0013] In the present invention, the substrate may be at least one selected from a polyester film, a cellulose film, and a polyimide film.

[0014] In the present invention, the maximum absorption wavelength of the near-ultraviolet absorbent may be 390 nm to 430 nm.

[0015] In the present invention, it may be characterized in that the near-ultraviolet absorbent is a cyanine compound.

[0016] In the present invention, the maximum absorption wavelength of the ultraviolet photosensitizer may be 350 nm to 400 nm.

[0017] In the present invention, it may be characterized in that the ultraviolet photosensitizer is an oxazole compound.

[0018] In the present invention, the hard coating layer is manufactured from a hard coating composition, and the hard coating composition may include a near-ultraviolet absorbent, an ultraviolet photosensitizer, a photocurable resin, and a solvent.

[0019] In the present invention, the near-ultraviolet absorbent may be included in an amount of 0.1 to 1 part by weight based on the total weight of the hard coating composition.

[0020] In the present invention, the ultraviolet photosensitizer may be included in an amount of 0.1 to 2 parts by weight based on the total weight of the hard coating composition.

[0021] In the present invention, the total light transmittance of the laminated film may be 85% or more. More preferably, the total light transmittance of the laminated film may be 90% or more.

[0022] In the present invention, the haze of the laminated film may be 2% or less.

[0023] In the present invention, the transmittance of the laminated film at a wavelength of 360 nm may be 5% or less.

[0024] In the present invention, the transmittance of the laminated film at a wavelength of 380 nm may be 5% or less.

[0025] In the present invention, the transmittance of the laminated film at a wavelength of 400 nm may be 10% or less.

[0026] Additionally, the present invention may relate to an image display device including the laminated film.

[0027]

[0028] According to the laminated film according to the present invention, the transmittance in the ultraviolet and / or near ultraviolet region is low, so that ultraviolet and / or near ultraviolet rays are effectively blocked, thereby preventing deterioration of OLED elements and improving the problem of shortened lifespan of displays.

[0029] In addition, according to the laminated film according to the present invention, the haze value is low, so that high transparency is exhibited, and the ultraviolet curing efficiency of the hard coating layer can be maintained while blocking ultraviolet rays by including an ultraviolet photosensitizer, thereby ensuring sufficient adhesion to the substrate, and thus, a laminated film having excellent physical and / or optical properties and an image display device including the same can be provided.

[0030]

[0031] FIG. 1 is a drawing showing a laminated structure of a laminated film in which a near-ultraviolet ray shielding hard coating layer (100) and an ultraviolet ray blocking substrate (200) are sequentially laminated according to one embodiment of the present invention.

[0032] In the above drawing 1, each symbol represents the following:

[0033] 100: Hard coating layer

[0034] 200: Description

[0035]

[0036] The present invention relates to a laminated film comprising a hard coating layer and a substrate, wherein the hard coating layer comprises a near-ultraviolet absorbent and an ultraviolet photosensitizer, and the substrate is a ultraviolet blocking substrate, and to an image display device comprising the same.

[0037] According to one embodiment of the present invention, the laminated film may be formed by sequentially laminating a hard coating layer including a near-ultraviolet absorbent and an ultraviolet photosensitizer; and an ultraviolet blocking substrate.

[0038] According to one embodiment of the present invention, the laminated film may be characterized by having a low transmittance of 10% or less, preferably 9% or less, and more preferably 7% or less at a wavelength of 360 nm and / or 380 nm and / or 400 nm, and most preferably, the transmittance may be 5%, 5%, and 10% or less at wavelengths of 360 nm, 380 nm, and 400 nm, respectively. In this case, ultraviolet and / or near ultraviolet rays are effectively blocked, and thus deterioration of the OLED element is prevented, thereby improving the problem of shortening the lifespan of the display.

[0039] According to one embodiment of the present invention, the hard coating layer includes an ultraviolet photosensitizer, so that it can maintain the ultraviolet curing efficiency of the hard coating layer while blocking ultraviolet rays, thereby ensuring sufficient adhesion to the substrate, and thus providing a laminated film suitable for protecting an OLED element.

[0040]

[0041] Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. However, the following drawings attached to this specification illustrate preferred embodiments of the present invention and, together with the contents of the invention described above, serve to further understand the technical concept of the present invention. Therefore, the present invention should not be interpreted as being limited to the matters described in such drawings.

[0042] The terms used herein are for the purpose of describing embodiments and are not intended to limit the invention.

[0043] As used herein, the terms "comprises" and / or "comprising" are used to mean that they do not exclude the presence or addition of one or more other components, steps, operations, and / or elements other than the components, steps, operations, and / or elements mentioned. Like reference numerals refer to like elements throughout the specification.

[0044] Spatially relative terms such as “below,” “bottom,” “lower,” “above,” “top,” and “upper” can be used to easily describe the relationship between one element or component and other elements or components, as depicted in the drawings. Spatially relative terms should be understood to include different orientations of the elements during use or operation in addition to the orientation depicted in the drawings. For example, if an element depicted in a drawing is flipped over, an element described as “below” or “lower” of another element may end up “above” the other element. Thus, the exemplary term “below” can include both the above and below directions. Elements can also be oriented in other directions, and thus spatially relative terms can be interpreted based on their orientation.

[0045]

[0046] In the present invention, “transparent” means that the visible light transmittance is 70% or more, preferably 80% or more.

[0047] In the present invention, “ultraviolet rays” means a wavelength of 100 nm to 390 nm, and “near ultraviolet rays” means a wavelength of 390 nm to 430 nm.

[0048] In the present invention, “shielding” and “blocking” are used practically without distinction to mean preventing from being affected by light such as ultraviolet rays or near ultraviolet rays.

[0049]

[0050] <Laminated film>

[0051] Referring to FIG. 1, a laminated film according to one embodiment of the present invention may include a hard coating layer (100); and a substrate (200).

[0052]

[0053] Hard coating layer (100)

[0054] The hard coating layer of the present invention is a layer that exhibits high adhesion due to excellent curing degree while blocking near-ultraviolet rays.

[0055] Specifically, the hard coating layer of the present invention is characterized by including a near-ultraviolet absorber and an ultraviolet photosensitizer, and by including the ultraviolet photosensitizer, it is possible to maintain the ultraviolet curing efficiency of the hard coating layer while blocking ultraviolet rays, thereby ensuring sufficient adhesion to a substrate, and thus providing a laminated film suitable for protecting an OLED element.

[0056] The hard coating layer (100) according to one embodiment of the present invention may be manufactured using a hard coating composition. Specifically, the hard coating composition may include at least one selected from the group consisting of a near-ultraviolet absorber, an ultraviolet photosensitizer, a photocurable resin, and a solvent, and may further include additives. In addition, other known components included in hard coating compositions in the art may be further included without limitation, as long as they do not affect the purpose and effects of the present invention.

[0057] The hard coating layer (100) is formed on a substrate (200) to be described later, and the hard coating layer (100) according to one embodiment of the present invention can be manufactured by applying a hard coating composition on the substrate (200) and then curing it with light or heat. The hard coating composition according to one embodiment of the present invention can be a hard coating composition that has excellent adhesion to the substrate (200) and can improve ultraviolet and / or near-ultraviolet shielding properties.

[0058]

[0059] near-ultraviolet absorbers

[0060] The near-ultraviolet absorber used in forming the hard coating layer according to one embodiment of the present invention is a component distinct from the ultraviolet stabilizer described below, and may be one that transmits ultraviolet rays and selectively absorbs near-ultraviolet rays. The near-ultraviolet absorber according to one embodiment of the present invention may have a maximum absorption wavelength of 390 nm to 430 nm, preferably 395 nm to 425 nm, and more preferably 400 nm to 420 nm. The near-ultraviolet absorber may be, for example, at least one selected from a cyanine-based compound, a benzophenone-based compound, a benzotriazole-based compound, and a triazine-based compound, and is preferably a cyanine-based compound in order to effectively absorb near-ultraviolet rays in the 390 nm to 430 nm range.

[0061] The above near-ultraviolet absorbent may be included in an amount of 0.01 to 5 parts by weight, preferably 0.1 to 1 part by weight, and more preferably 0.3 to 0.7 parts by weight, based on the total weight of the hard coating composition.

[0062]

[0063] UV photosensitizer

[0064] The ultraviolet photosensitizer used in forming a hard coating layer according to one embodiment of the present invention functions to absorb ultraviolet rays to block ultraviolet rays while transferring energy (absorbed and then re-emitted) to an initiator included in a hard coating composition through a photochemical reaction, thereby promoting curing of the hard coating layer. The ultraviolet photosensitizer serves to maintain a low transmittance by absorbing light in the ultraviolet region through this series of photochemical reactions, while simultaneously inducing an initiation reaction of an initiator that causes a crosslinking reaction of an ultraviolet-curable material. When the laminated film according to one embodiment of the present invention includes the ultraviolet photosensitizer, adhesion to the substrate can be improved.

[0065] The ultraviolet photosensitizer according to one embodiment of the present invention may have a maximum absorption wavelength of 350 nm to 400 nm, preferably 355 nm to 395 nm, and more preferably 360 nm to 390 nm.

[0066] As the above ultraviolet photosensitizer, for example, at least one selected from oxazole, anthraquinone, naphthoquinone, quinone, thioxanthone, acridone, benzoyldiphenylphosphine oxide, 1,2-diketone, phenothiazine, ketocoumarin, fluorene, naphthiazoline, biacetyl, benzyl and derivatives thereof, perylene and substituted / unsubstituted anthracene may be used. In view of the fact that it can effectively absorb ultraviolet rays in the range of 350 nm to 400 nm, it is preferably an oxazole-based compound.

[0067] The above ultraviolet photosensitizer may be included in an amount of 0.01 to 5 parts by weight, preferably 0.1 to 2 parts by weight, and more preferably 0.5 to 1.5 parts by weight, based on the total weight of the hard coating composition.

[0068]

[0069] photocurable resin

[0070] The photocurable resin used in forming the hard coating layer of the present invention contains a photopolymerizable functional group, and may be a photopolymerizable monomer, a photopolymerizable oligomer, or the like, and may be, for example, a photoradically polymerizable compound.

[0071] The photopolymerizable monomer is a commonly used photocurable functional group, and for example, any monomer used in the relevant technical field having an unsaturated group in the molecule, such as a (meth)acryloyl group, a vinyl group, a styryl group, or an allyl group, can be used without limitation. More specifically, examples thereof include monofunctional and / or polyfunctional (meth)acrylates. These may be used alone or in combination of two or more.

[0072] In the present invention, “(meth)acryl-” refers to “methacryl-”, “acryl-” or both.

[0073] Specific examples of (meth)acrylate monomers include (meth)acrylic acid esters, such as trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, glycerol tri(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, ethylene glycol di(meth)acrylate, propylene glycol (meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentylglycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, Bis(2-hydroxyethyl)isocyanurate di(meth)acrylate, poly(meth)acrylates obtained by adding ethylene oxide or propylene oxide to the (meth)acrylic acid ester; oligoester (meth)acrylates having 1 to 3 (meth)acryloyl groups in the molecule, oligoether (meth)acrylic acid esters, oligourethane (meth)acrylic acid esters, and oligoepoxy (meth)acrylic acid esters; hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, and products obtained by adding ethylene oxide or propylene oxide to the (meth)acrylic acid esters; And monomers having a trifunctional or less (meth)acryloyl group, such as mono(meth)acrylic acid esters, such as iso-octyl (meth)acrylate, iso-decyl (meth)acrylate, stearyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, and phenoxyethyl (meth)acrylate, and dipentaerythritol hexa(meth)acrylate, dipentaerythritol hydroxypenta(meth)acrylate, pentaerythritol tetra(meth)acrylate, and ditrimethylolpropane tetra(meth)acrylate, etc. These may be used alone or in mixtures of two or more.

[0074] The photopolymerizable oligomer may be, for example, at least one selected from the group consisting of epoxy (meth)acrylate, urethane (meth)acrylate, and polyester (meth)acrylate. Specifically, a mixture of urethane (meth)acrylate and polyester (meth)acrylate may be used, or a mixture of two types of polyester (meth)acrylates may be used. It is preferable to include a urethane (meth)acrylate oligomer to improve the scratch resistance and hardness of the cured product and to increase the elastic modulus of the hard coating layer.

[0075] The above urethane (meth)acrylate can be produced by reacting a polyfunctional (meth)acrylate having a hydroxyl group in the molecule with a compound having an isocyanate group in the presence of a catalyst according to a method known in the art.

[0076] Specific examples of the polyfunctional (meth)acrylate having a hydroxyl group in the molecule may be at least one selected from the group consisting of 2-hydroxyethyl (meth)acrylate, 2-hydroxyisopropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, caprolactone ring-opening hydroxyacrylate, pentaerythritol tri / tetra(meth)acrylate mixture, and dipentaerythritol penta / hexa(meth)acrylate mixture.

[0077] Also, specific examples of compounds having an isocyanate group include 1,4-diisocyanatobutane, 1,6-diisocyanatohexane, 1,8-diisocyanatooctane, 1,12-diisocyanatododecane, 1,5-diisocyanato-2-methylpentane, trimethyl-1,6-diisocyanatohexane, 1,3-bis(isocyanatomethyl)cyclohexane, trans-1,4-cyclohexenediisocyanate, 4,4'-methylenebis(cyclohexylisocyanate), isophoronediisocyanate, toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, xylene-1,4-diisocyanate, tetramethylxylene-1,3-diisocyanate, It may be at least one selected from the group consisting of 1-chloromethyl-2,4-diisocyanate, 4,4'-methylenebis(2,6-dimethylphenylisocyanate), 4,4'-oxybis(phenylisocyanate), a trifunctional isocyanate derived from hexamethylene diisocyanate, and trimethanepropanol adduct toluene diisocyanate.

[0078] More specifically, the urethane (meth)acrylate oligomer may be a compound containing two or more substituents and (meth)acrylate groups each represented by the following chemical formula 1 within the molecule.

[0079] [Chemical Formula 1]

[0080] *-OC(=O)NH-*

[0081] The above urethane (meth)acrylate oligomer may be produced by reacting 1 mol of diisocyanate represented by the following chemical formula 2 with 2 mol of an active hydrogen-containing polymerizable unsaturated compound.

[0082] [Chemical Formula 2]

[0083] R1-OC(=O)NH-R3-NHC(=O)O-R2

[0084] In the formula, R1 and R2 are each independently a substituent including a (meth)acryloyl group derived from an active hydrogen-containing polymerizable unsaturated compound, and R3 is a divalent substituent derived from diisocyanate.

[0085] Specific examples of urethane (meth)acrylate oligomers include the reaction of 2-hydroxyethyl (meth)acrylate and 2,4-tolylene diisocyanate, the reaction of 2-hydroxyethyl (meth)acrylate and isophorone diisocyanate, the reaction of 2-hydroxybutyl (meth)acrylate and 2,4-tolylene diisocyanate, the reaction of 2-hydroxybutyl (meth)acrylate and isophorone diisocyanate, the reaction of pentaerythritol tri(meth)acrylate and 2,4-toluene diisocyanate, the reaction of pentaerythritol tri(meth)acrylate and isophorone diisocyanate, the reaction of pentaerythritol tri(meth)acrylate and dicyclohexyl methane diisocyanate, and dipentaerythritol. It may be a product of the reaction of penta(meth)acrylate and isophorone diisocyanate, or of the reaction of dipentaerythritol penta(meth)acrylate and dicyclohexyl methane diisocyanate.

[0086] Polyester (meth)acrylate can be prepared by reacting polyester polyol and acrylic acid according to a method known in the art.

[0087] The polyester (meth)acrylate may be selected from the group consisting of, but is not limited to, at least one selected from the group consisting of polyester acrylate, polyester diacrylate, polyester tetraacrylate, polyester hexaacrylate, polyester pentaerythritol triacrylate, polyester pentaerythritol tetraacrylate, and polyester pentaerythritol hexaacrylate.

[0088] The photopolymerizable monomer and the photopolymerizable oligomer can be used alone or in combination. When the photopolymerizable monomer and the photopolymerizable oligomer are used in combination, the workability and compatibility of the hard coating composition can be increased.

[0089] The content ratio of the photopolymerizable monomer and the photopolymerizable oligomer is not particularly limited and may be appropriately selected in consideration of the storage elastic modulus, shrinkage force, and workability of the hard coating layer. For example, the content ratio of the polymerizable oligomer to the polymerizable monomer may be included in a ratio of 1:10 to 10:1. If the content ratio of the polymerizable oligomer to the polymerizable monomer is outside the above range, the storage elastic modulus of the hard coating layer may decrease or the shrinkage force may increase, resulting in a decrease in hardness and flexibility, which may cause curling.

[0090] The content of the photocurable resin is not particularly limited, but may be included in an amount of, for example, 1 to 80 parts by weight, preferably 1 to 50 parts by weight, based on 100 parts by weight of the total hard coating composition. If the photocurable resin is less than 1 part by weight, the elastic modulus of the hard coating layer decreases, so that cracks may easily occur in the hard coating layer when bent. If it exceeds 80 parts by weight, the viscosity increases, so that the applicability decreases, and the surface leveling is insufficient, which may cause problems with the appearance characteristics.

[0091]

[0092] Initiator

[0093] The above initiator may be used without limitation as long as it is used in the relevant technical field. For example, one or more selected from the group consisting of hydroxyketones, aminoketones, hydrogen-abstracting photoinitiators, and combinations thereof may be used.

[0094] Specifically, the photoinitiator may be at least one selected from the group consisting of 2-methyl-1-[4-(methylthio)phenyl]2-morpholinepropanone-1, diphenyl ketone, benzyldimethyl ketal, 2-hydroxy-2-methyl-1-phenyl-1-one, 4-hydroxycyclophenyl ketone, 2,2-dimethoxy-2-phenyl-acetophenone, anthraquinone, fluorene, triphenylamine, carbazole, 3-methylacetophenone, 4-xenoloacetophenone, 4,4-dimethoxyacetophenone, 4,4-diaminobenzophenone, 1-hydroxycyclohexylphenyl ketone, benzophenone, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, and combinations thereof.

[0095] These photoinitiators are used in an amount of 0.1 to 10 parts by weight, preferably 0.3 to 5 parts by weight, based on 100 parts by weight of the total hard coating composition. If the content is less than the above range, the curing speed of the composition is slow and uncured, resulting in poor mechanical properties. Conversely, if the content exceeds the above range, cracks may occur in the coating film due to overcuring.

[0096]

[0097] solvent

[0098] The above solvent can be used without limitation as long as it is known as a solvent for a composition for forming a coating layer in the technical field of the present invention that can dissolve or disperse the composition mentioned above.

[0099] Available solvents include alcohols (methanol, ethanol, isopropanol, butanol, methyl cellusob, ethylsolusob, etc.), ketones (methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone, dipropyl ketone, cyclohexanone, etc.), acetates (ethyl acetate, propyl acetate, normal butyl acetate, tert-butyl acetate, methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, methoxybutyl acetate, methoxypentyl acetate, etc.), hexane-based solvents (hexane, heptane, octane, etc.), benzene-based solvents (benzene, toluene, xylene, etc.), ether-based solvents (diethylene glycol dimethyl ether, diethylene glycol diethyl ether, Diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, etc.) can be preferably used. The solvents exemplified above can be used alone or in combination of two or more.

[0100] These solvents can be used in an amount of 10 to 95 parts by weight based on 100 parts by weight of the entire hard coating composition, and can be included as a remainder excluding other components in the composition. If the content of the solvent is less than the above content, the viscosity will be high, resulting in poor workability and inability to sufficiently promote swelling of the base film. Conversely, if the content exceeds the above range, the drying process will take a long time and be economical, so it is appropriately used within the above range.

[0101]

[0102] additives

[0103] In addition, the hard coating composition used to form the hard coating layer according to the present invention may further include, in addition to the above-described components, one or more additives selected from the group consisting of a leveling agent, an ultraviolet stabilizer, and a heat stabilizer, and may further include additives commonly used in the technical field to which the present invention pertains. In addition, the content thereof may be adjusted in various ways within a range that does not deteriorate the physical properties of the hard coating composition according to the present invention, and is therefore not particularly limited.

[0104] A leveling agent is a component that provides smoothness and coatability to a coating film. The leveling agent may be any leveling agent commonly used in the art, and examples thereof include silicone-based leveling agents, fluorine-based leveling agents, and acrylic polymer-based leveling agents. These may be used alone or in combination of two or more, but are not necessarily limited thereto. In an embodiment of the present invention, the hard coating layer preferably further includes a silicone-based or acrylic polymer-based additive instead of the fluorine-based UV-curable functional group-containing compound included in the low-refractive-index layer, which will be described later, to lower the contact angle and facilitate coating of the low-refractive-index layer on the hard coating layer.

[0105] The leveling agent may be included in an amount of 0.1 to 1 part by weight per 100 parts by weight of the hard coating composition, but is not limited thereto.

[0106] A UV stabilizer is a component that blocks or absorbs ultraviolet rays, thereby preventing decomposition, discoloration, and crumbling of a cured hard coating layer due to exposure to ultraviolet rays. In addition to absorbents, the UV stabilizer of the present invention may be classified by mechanism of action, such as quenchers and hindered amine light stabilizers (HALS); or by chemical structure, such as phenyl salicylates (absorbents), benzophenone (absorbents), benzotriazole (absorbents), nickel derivatives (quenchers), and radical scavengers. These may be used singly or in combination of two or more, and the type of UV stabilizer is not particularly limited as long as it does not significantly change the initial color of the hard coating layer.

[0107] For example, commercially applicable products include polyphenol-based primary heat stabilizers, phosphate-based secondary heat stabilizers, and lactone-based secondary heat stabilizers, which can be used singly or in combination. These can be used singly or in combination of two or more types.

[0108] The above UV stabilizer and heat stabilizer can be used by adjusting the content appropriately at a level that does not affect UV curability, and specifically, it is preferable to include 0.1 to 3 parts by weight based on 100 parts by weight of the total hard coating composition of the present invention.

[0109]

[0110] The above additives can be added by appropriately adjusting the content within a range that does not impede the effects of the present invention.

[0111] The hard coating layer may be manufactured by a method known in the art. The thickness of the hard coating layer is not particularly limited, but may be, for example, 1 to 15 μm, and preferably 2 to 10 μm. When the thickness is within the above range, it is easy to control the transmittance of the laminated film including the heart coating layer at a wavelength of 360 nm and / or 380 nm to 5% or less, and shrinkage occurring during curing can be reduced, so that a film without severe curling can be obtained, facilitating the manufacturing process. On the other hand, when the thickness of the hard coating layer exceeds the above range, there is a disadvantage in that severe curling occurs due to curing, resulting in breakage during the manufacturing process.

[0112]

[0113] A laminated film according to an embodiment of the present invention may be formed by coating a hard coating composition on a substrate and performing drying and UV curing steps to form a hard coating layer (100).

[0114] The step of drying the above laminated film can be performed by a heating means such as a hot plate, a hot air circulator, or an infrared furnace, and can be performed at a temperature of 50 to 150°C or 50 to 100°C.

[0115] The step of curing the above laminated film is 50 to 1000 mJ / cm 2 , preferably 200 to 800 mJ / cm 2 Investigate active rays such as UV rays. Light sources used for investigation include low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, and argon gas lasers. In some cases, X-rays and electron beams can also be used.

[0116]

[0117] Description (200)

[0118] According to one embodiment of the present invention, the substrate (200) is preferably a UV-blocking substrate, and specifically, from the standpoint of display protection, it is preferable that the transmittance at a wavelength of 380 nm be 10% or less. When the transmittance of the substrate at a wavelength of 380 nm is 10% or less, there is an advantage in that wavelengths in the UV range can be effectively blocked, thereby ensuring the degree of curing of the coating layer. The UV-blocking substrate of the present invention includes a UV-blocking additive having a UV-blocking function.

[0119] The above-mentioned substrate may, in addition to its UV blocking function, have a function of mitigating impact and preventing damage to the internal substrate when damage such as impact and / or scratch is applied to the entire surface of the substrate layer. Accordingly, a material having a high tolerance for deformation energy is preferable, and examples thereof include polyester resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate; polyimide resins; acrylic resins; styrene resins such as polystyrene and acrylonitrile-styrene; polycarbonate resins; polylactic acid resins; polyurethane resins; polyolefin resins such as polyethylene, polypropylene, and ethylene-propylene copolymers; vinyl resins such as polyvinyl chloride and polyvinylidene chloride; polyamide resins; sulfone resins; polyether-etherketone resins; allylate resins; There are also release films formed from cellulose-based resins such as triacetyl cellulose or mixtures of the above resins. In one embodiment of the present invention, cellulose-based resins are most preferred due to their optical transparency and excellent durability against friction, heat, and / or chemical damage.

[0120] The thickness of the substrate using the above cellulose-based resin can be applied without limitation, but the thicker it is, the heavier it is and the lower the handling ability, so a thickness of 25 to 80㎛ is preferable as a display protection film.

[0121] The substrate (200) according to one embodiment of the present invention may include a UV-blocking additive. When the substrate includes a UV-blocking additive, it can effectively block ultraviolet rays in the range of 400 nm or less, thereby preventing deterioration of OLED elements and improving the problem of shortened lifespan of the display. The UV-blocking additive may be, but is not limited to, a benzophenone compound, a benzotriazole, or a triazine compound, and is preferably included in an amount of 0.1% to 10% based on the total weight of the composition forming the substrate.

[0122]

[0123] The thickness of the above-mentioned substrate is not particularly limited and may be, for example, 10 to 100 μm. When the thickness is within the above range, it is suitable and preferable as a display protection film.

[0124]

[0125] <Video display device>

[0126] FIG. 1 is a diagram illustrating a laminated structure of a laminated film according to an embodiment of the present invention. Referring to FIG. 1, embodiments of the present invention provide a laminated film including a hard coating layer (100); and a substrate (200), and an image display device including the same.

[0127] For example, a laminated film may be formed by sequentially laminating the hard coating layer (100) and the substrate (200) described above. At this time, the laminated film including the hard coating layer (100) and the substrate (200) may be formed on the outermost surface according to the needs of the image display device, and may also be inserted into the interior of the image display device.

[0128]

[0129] The above image display device includes various image display devices such as a liquid crystal display device, an electroluminescent display device, a plasma display device, a field emission display device, etc., and may be a flexible display device having flexibility and bending characteristics, but is not limited thereto. In this case, the laminated film according to the embodiments of the present invention, i.e., the hard coating laminate, acts to reduce the transmittance in the ultraviolet and / or near ultraviolet region and improve the mechanical properties such as adhesion through the above configuration, thereby preventing haze and deterioration of the OLED element, and implementing an image display device having excellent total transmittance and adhesion.

[0130]

[0131] Hereinafter, the present invention will be described in more detail based on examples. However, the embodiments of the present invention disclosed below are merely illustrative, and the scope of the present invention is not limited to these embodiments. The scope of the present invention is indicated in the claims, and furthermore, it includes all modifications within the meaning and scope equivalent to the claims. In addition, "%" and "parts" indicating contents in the following examples and comparative examples are based on weight unless otherwise specified.

[0132]

[0133] Manufacturing Examples 1 to 5: Manufacturing of hard coating composition

[0134]

[0135] Manufacturing Example 1

[0136] 50.8 parts by weight of hexafunctional urethane acrylate (UA-306I, Gongyoung Corporation), 44.6 parts by weight of butyl acetate, 3.3 parts by weight of 1-hydroxycyclohexylphenyl ketone, 0.3 parts by weight of silicone-based leveling agent (BYK-UV3530, BYK Corporation), 0.5 parts by weight of near-ultraviolet absorber (FDB-009 (λmax=402 nm), Yamada Corporation), 0.5 parts by weight of ultraviolet photosensitizer (NF-TH-01 (λmax=375 nm), Nippon Chemical Works Corporation) were mixed using a stirrer and filtered using a PP filter to prepare a hard coating composition.

[0137]

[0138] Manufacturing Example 2

[0139] 50.6 parts by weight of hexafunctional urethane acrylate (UA-306I, Gongyoung Corporation), 44.2 parts by weight of butyl acetate, 3.3 parts by weight of 1-hydroxycyclohexylphenyl ketone, 0.3 parts by weight of silicone-based leveling agent (BYK-UV3530, BYK Corporation), 0.5 parts by weight of near-ultraviolet absorber (FDB-009 (λmax=402nm), Yamada Corporation), 1.1 parts by weight of ultraviolet photosensitizer (NF-NA-01 (λmax=379nm), Nippon Chemical Works Corporation) were mixed using a stirrer and filtered using a PP material filter to prepare a hard coating composition.

[0140]

[0141] Manufacturing Example 3

[0142] 50.0 parts by weight of 6-functional urethane acrylate (UA-306I, Gongyoung), 43.8 parts by weight of butyl acetate, 3.2 parts by weight of 1-hydroxycyclohexylphenyl ketone, 0.3 parts by weight of silicone-based leveling agent (BYK-UV3530, BYK), and 2.7 parts by weight of ultraviolet absorbent (TINUVIN 970 (λmax=378nm), BASF) were mixed using a stirrer and filtered using a PP filter to prepare a hard coating composition.

[0143]

[0144] Manufacturing Example 4

[0145] 51.1 parts by weight of 6-functional urethane acrylate (UA-306I, Gongyoung Corporation), 44.8 parts by weight of butyl acetate, 3.3 parts by weight of 1-hydroxycyclohexylphenyl ketone, 0.3 parts by weight of silicone-based leveling agent (BYK-UV3530, BYK Corporation), and 0.5 parts by weight of near-ultraviolet absorbent (FDB-009 (λmax=402 nm), Yamada Corporation) were mixed using a stirrer and filtered using a PP material filter to prepare a hard coating composition.

[0146]

[0147] Manufacturing Example 5

[0148] 49.8 parts by weight of 6-functional urethane acrylate (UA-306I, Gongyoung), 43.5 parts by weight of butyl acetate, 3.2 parts by weight of 1-hydroxycyclohexylphenyl ketone, 0.3 parts by weight of silicone-based leveling agent (BYK-UV3530, BYK), 2.7 parts by weight of ultraviolet absorber (TINUVIN 970 (λmax=378nm), BASF), 0.5 parts by weight of near-ultraviolet absorber (FDB-009 (λmax=402nm)) were mixed using a stirrer and filtered using a PP material filter to prepare a hard coating composition.

[0149]

[0150]

[0151] Examples 1 to 2 and Comparative Examples 1 to 4: Preparation of laminated films

[0152] Example 1

[0153] The hard coating composition manufactured according to the above Manufacturing Example 1 was coated on a UV-blocking substrate (80㎛ TAC film, Hyosung Corporation) to a thickness of 6㎛ after curing, and the solvent was dried and UV accumulated light intensity was 500mJ / cm in a nitrogen atmosphere. 2 A laminated film is manufactured by investigating the same.

[0154]

[0155] Example 2

[0156] The hard coating composition manufactured according to the above Manufacturing Example 2 was coated on a UV-blocking substrate (80㎛ TAC film, Hyosung Corporation) to a thickness of 6㎛ after curing, and the solvent was dried and UV accumulated light intensity was 500mJ / cm in a nitrogen atmosphere. 2 A laminated film is manufactured by investigating the same.

[0157]

[0158] Comparative Example 1

[0159] The hard coating composition manufactured according to the above Manufacturing Example 3 was coated on a UV-blocking substrate (80㎛ TAC film, Hyosung Corporation) to a thickness of 6㎛ after curing, and the solvent was dried and UV accumulated light intensity was 500mJ / cm in a nitrogen atmosphere. 2 A laminated film is manufactured by investigating the same.

[0160]

[0161] Comparative Example 2

[0162] The hard coating composition manufactured according to the above Manufacturing Example 4 was coated on a UV-blocking substrate (80㎛ TAC film, Hyosung Corporation) to a thickness of 6㎛ after curing, and the solvent was dried and UV accumulated light intensity was 500mJ / cm in a nitrogen atmosphere. 2 A laminated film is manufactured by investigating the same.

[0163]

[0164] Comparative Example 3

[0165] The hard coating composition manufactured according to the above Manufacturing Example 5 was coated on a UV-blocking substrate (80㎛ TAC film, Hyosung Corporation) to a thickness of 6㎛ after curing, and the solvent was dried and UV accumulated light intensity was 500mJ / cm in a nitrogen atmosphere. 2 A laminated film is manufactured by investigating the same.

[0166]

[0167] Comparative Example 4

[0168] The hard coating composition manufactured according to the above Manufacturing Example 1 was coated on a transparent substrate (80㎛ ZRT film, Hyosung Corporation) to a thickness of 6㎛ after curing, and the solvent was dried and UV accumulated light intensity was 500mJ / cm in a nitrogen atmosphere. 2 A laminated film is manufactured by investigating the same.

[0169]

[0170] The manufacturing examples and usage materials applied to Examples 1 to 2 and Comparative Examples 1 to 4, respectively, and the thickness of each layer follow the contents described in Table 1 below.

[0171] Hard coating layer (100) Substrate (200) Exclusion composition Manufacturing example Coating thickness (㎛) Substrate thickness (㎛) Example 1 Manufacturing example 16 Ultraviolet-blocking substrate 80 - Example 2 Manufacturing example 26 Ultraviolet-blocking substrate 80 - Comparative example 1 Manufacturing example 36 Ultraviolet-blocking substrate 80 Near-ultraviolet absorber and ultraviolet photosensitizer Comparative example 2 Manufacturing example 46 Ultraviolet-blocking substrate 80 Ultraviolet photosensitizer Comparative example 3 Manufacturing example 56 Ultraviolet-blocking substrate 80 Ultraviolet photosensitizer Comparative example 4 Manufacturing example 16 Transparent substrate 80 Ultraviolet-blocking substrate

[0172] Experimental example

[0173] The physical properties of the laminated films manufactured in Examples 1 to 2 and Comparative Examples 1 to 4 were measured by the following methods, and the results are shown in Table 2.

[0174]

[0175] (1) Measurement of UV (360 nm) transmittance

[0176] The transmittance of the laminated films of the above examples and comparative examples at a wavelength of 360 nm was measured using UV-2600 (Shimadzu Corporation) equipment, and the results are shown in Table 2.

[0177]

[0178] (2) Measurement of UV (380 nm) transmittance

[0179] The transmittance of the laminated films of the above examples and comparative examples at a wavelength of 380 nm was measured using UV-2600 (Shimadzu Corporation) equipment, and the results are shown in Table 2.

[0180]

[0181] (3) Measurement of near-ultraviolet (400 nm) transmittance

[0182] The transmittance of the laminated films of the above examples and comparative examples at a wavelength of 400 nm was measured using UV-2600 (Shimadzu Corporation) equipment, and the results are shown in Table 2.

[0183]

[0184] (4) Measurement of total transmittance (Tt)

[0185] The total light transmittance of the laminated films of the above examples and comparative examples was measured using a haze meter (HR-100, Murakami) according to JIS 7136, and the results are shown in Table 2.

[0186]

[0187] (5) Haze measurement

[0188] The haze of the laminated films of the above examples and comparative examples was measured according to JIS 7136 using a haze meter (HR-100, Murakami Co.), and the results are shown in Table 2.

[0189]

[0190] (6) Adhesion evaluation

[0191] After attaching the substrate film to the glass using a transparent adhesive so that the hard coating surface faces upward, scratches were made on the hard coating surface with a cutter knife in the shape of 100 squares in length and width at 1 mm intervals, and an adhesion test was performed three times using niche tape.

[0192] <Evaluation Criteria>

[0193] - 0B: 65% or more peeling

[0194] - 1B: Peeling of 35% or more but less than 65%

[0195] - 2B: 15% or more but less than 35% peeling

[0196] - 3B: Peeling of 5% or more but less than 15%

[0197] - 4B: Less than 5% peeling

[0198] - 5B: Unpeeled

[0199]

[0200] Transmittance [%] Total light transmittance [%] Haze [%] Adhesion 360 nm 380 nm 400 nm Example 10.000.16 5.5 8 9 1.5 0.25 B Example 20.000.06 3.2 1 9 1.7 0.25 B Comparative Example 10.000.36 17.7 9 2.10.30 B Comparative Example 20.000.74 13.13 9 2.10.45 B Comparative Example 30.000.08 2.6 3 9 2.00.40 B Comparative Example 49.3 6 4.3 9 5.8 2 9 1.6 0.15 B

[0201] According to the experimental data in Table 2 above, as a result of evaluating the properties of the laminated films manufactured in Examples 1 and 2 according to the present invention, the films of the examples satisfied transmittances of 5%, 5%, and 10% or less at 360 nm, 380 nm, and 400 nm, respectively, and did not peel off in the adhesion evaluation, showing excellent ultraviolet and near-ultraviolet ray shielding effects and excellent adhesion effects.

[0202] On the other hand, in the case of Comparative Example 1, which applied a hard coating composition that did not include a near-ultraviolet absorber and an ultraviolet photosensitizer, it was found that the transmittance in the 400 nm wavelength range was higher than that of the example according to the present invention, and thus the near-ultraviolet shielding effect was significantly reduced.

[0203] In addition, in the case of Comparative Example 3, which applied a hard coating composition that did not include an ultraviolet ray photosensitizer, it was found that the adhesion was significantly lower than that of the example according to the present invention, making it unsuitable as a film for protecting OLED elements.

[0204] In addition, in the case of Comparative Example 4, which did not use a UV-blocking material, it was found that the transmittance in the 360 ​​nm and 380 nm wavelength ranges was higher than that of the example according to the present invention, and thus the UV-blocking effect was significantly reduced.

[0205] In summary of these results, if any one of the hard coating layer including the near-ultraviolet absorber and the ultraviolet photosensitizer, which are the components of the present invention, and the substrate including the ultraviolet blocking additive is excluded from the components of the present invention,

[0206] It can be seen that one or more of the results in the above UV transmittance, near-UV transmittance, and adhesion evaluations are poor results that fall short of the examples of the present invention.

[0207] Accordingly, a laminated film according to one embodiment of the present invention comprises a hard coating layer; and a substrate, wherein the hard coating layer comprises a near-ultraviolet absorbent and a ultraviolet photosensitizer, and the substrate comprises a ultraviolet blocking additive, so that the laminated film has an excellent ultraviolet and / or near-ultraviolet shielding effect and can maintain excellent mechanical properties such as adhesion.

[0208]

[0209] According to the laminated film according to the present invention, the transmittance in the ultraviolet and / or near ultraviolet region is low, so that ultraviolet and / or near ultraviolet rays are effectively blocked, thereby preventing deterioration of OLED elements and improving the problem of shortened lifespan of displays.

Claims

1. A laminated film comprising a hard coating layer and a substrate, The above hard coating layer includes a near-ultraviolet absorber and an ultraviolet photosensitizer, The above description is a UV blocking material. Laminated film.

2. In claim 1, The above description is characterized in that the transmittance at a wavelength of 380 nm is 10% or less. Laminated film.

3. In claim 1, The above-mentioned material is characterized in that it contains a UV blocking additive. Laminated film.

4. In claim 1, The above-mentioned substrate is characterized in that it is at least one selected from a polyester film, a cellulose film, and a polyimide film. Laminated film.

5. In claim 1, The above near-ultraviolet absorbent is characterized in that the maximum absorption wavelength is 390 nm to 430 nm. Laminated film.

6. In claim 1, The above near-ultraviolet absorber is characterized in that it is a cyanine compound. Laminated film.

7. In claim 1, The above ultraviolet photosensitizer is characterized in that the maximum absorption wavelength is 350 nm to 400 nm. Laminated film.

8. In claim 1, The above ultraviolet photosensitizer is characterized in that it is an oxazole compound. Laminated film.

9. In claim 1, The above hard coating layer is manufactured from a hard coating composition, The hard coating composition is characterized in that it includes a near-ultraviolet absorber, an ultraviolet photosensitizer, a photocurable resin, and a solvent. Laminated film.

10. In claim 9, The above near-ultraviolet absorbent is characterized in that it is included in an amount of 0.1 to 1 part by weight based on the total weight of the hard coating composition. Laminated film.

11. In claim 9, The above ultraviolet photosensitizer is characterized in that it is included in an amount of 0.1 to 2 parts by weight based on the total weight of the hard coating composition. Laminated film.

12. In claim 1, The total transmittance of the laminated film is characterized by being 85% or more. Laminated film.

13. In claim 1, The haze of the laminated film is characterized by being 2% or less. Laminated film.

14. In claim 1, The above laminated film is characterized in that the transmittance at a wavelength of 360 nm is 5% or less. Laminated film.

15. In claim 1, The above laminated film is characterized in that the transmittance at a wavelength of 380 nm is 5% or less. Laminated film.

16. In claim 1, The above laminated film is characterized in that the transmittance at a wavelength of 400 nm is 10% or less. Laminated film.

17. Comprising a laminated film according to any one of claims 1 to 16, Video display device.

Images