Optical laminate and image display device comprising same

Abstract

The present invention relates to an optical laminate and an image display device comprising same, the optical laminate comprising: a thin film glass; a first hard coating layer formed on one surface of the thin film glass; and a second hard coating layer formed on the first hard coating layer, wherein the first hard coating layer comprises a silicone oligomer and an epoxy silane coupling agent, and the second hard coating layer comprises a photocurable resin. By forming the first hard coating layer having excellent pen-pressing resistance, pen marks do not remain, and by additionally laminating one more layer of the second hard coating layer on the upper surface of the first hard coating layer, durability such as hardness, scratch resistance, and anti-fingerprint performance are provided.

Description

Optical laminate and image display device including the same

[0001] The present invention relates to an optical laminate and an image display device including the same.

[0002] Recently, image display devices, such as liquid crystal displays (LCDs) and organic light emitting displays (OLEDs), have been continuously thinning and becoming more flexible. These image display devices are widely used in various smart devices characterized by portability, including not only smartphones and tablet PCs, but also various wearable devices. Such flexible displays require a glass substrate layer with properties such as high transparency and bending characteristics.

[0003] Meanwhile, cover windows for flexible displays are thin and easily broken, so they must be reinforced with a separate substrate. Since flexible displays cannot use the thick cover glass used for conventional rigid displays, a hard coat film is typically laminated onto thin glass for surface protection. However, this often leaves marks when using a pen due to poor pressure resistance. Increasing the thickness of the hard coat layer can be considered as a way to improve the pressure resistance of the hard coat layer. To ensure surface hardness that can replace glass, a certain hard coat layer thickness must be maintained. However, while increasing the thickness of the hard coat layer can improve the pressure resistance and surface hardness, it is not easy to apply practically because wrinkles and curls increase due to curing shrinkage of the hard coat layer, and cracks and peeling of the hard coat layer become more likely to occur. In addition, in the case of general (meth)acrylate or epoxy high-functional group photocurable composite resins, it is difficult to achieve high hardness corresponding to tempered glass, and there is a significant curl phenomenon due to shrinkage during curing, and flexibility is also insufficient, so there are disadvantages that it is not suitable as a protective window substrate for application to flexible displays. Korean Patent Publication No. 2010-0041992 discloses a hard coating film composition using a binder resin containing an ultraviolet-curable polyurethane acrylate oligomer. However, the hard coating film disclosed above is not only thick, but also has a pencil hardness of about 3H, which is not strong enough to replace the glass panel of a display, and there is no recognition of compression resistance.

[0004] Therefore, there is a need to develop an optical laminate having a hard coating layer that is applicable to flexible displays and has sufficient flexibility and bendability while not leaving a press mark even when using a pen.

[0005]

[0006] The present invention aims to provide an optical laminate having a first hard coating layer having excellent pressure resistance on a thin film glass of several μm in thickness so that pen marks are not left behind, and a second hard coating layer is further laminated on the upper surface of the first hard coating layer to provide durability such as hardness, scratch resistance, and anti-fingerprint performance.

[0007] Specifically, the present invention aims to provide an optical laminate having excellent pressure resistance, water contact angle, transmittance, haze, scratch resistance, adhesion, and bendability, 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] In order to achieve the above technical task, the present invention provides an optical laminate comprising a thin film glass, a first hard coating layer formed on one surface of the thin film glass, and a second hard coating layer formed on the first hard coating layer, wherein the first hard coating layer comprises a silicone oligomer and an epoxy silane coupling agent, and the second hard coating layer comprises a photocurable resin.

[0011] In the present invention, the silicone oligomer may include a cyclosiloxane group and an alicyclic substituent.

[0012] In the present invention, the alicyclic substituent may be characterized by being at least one of an alicyclic epoxy group and an oxetane group.

[0013] In the present invention, the silicone oligomer may be characterized by including an organic group represented by -(SiO2R2)-, wherein R is an alicyclic substituent, an alkyl group having 1 to 30 carbon atoms, an alkenyl group, or an alkynyl group.

[0014] In the present invention, the epoxy silane coupling agent may include at least one selected from 3-glycidoxypropyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 8-glycidoxyoctyltrimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0015] In the present invention, the photocurable resin of the second hard coating layer may include a urethane (meth)acrylate oligomer.

[0016] In the present invention, the second hard coating layer may include a fluorine-based leveling agent.

[0017] In the present invention, the fluorine-based leveling agent may include at least one selected from the group consisting of (meth)acrylate containing a perfluoroalkyl group, (meth)acrylate containing a perfluoroaliphatic group, and (meth)acrylate containing a perfluoroaromatic group.

[0018] In the present invention, the second hard coating layer is manufactured from a composition for forming a second hard coating layer, and may include 0.01 to 10 parts by weight of a fluorine-based leveling agent based on 100 parts by weight of the total composition for forming the second hard coating layer.

[0019] In the present invention, the thickness of the first hard coating layer may be 10 µm or more and 30 µm or less, and the thickness of the second hard coating layer may be 10 µm or more and 30 µm or less.

[0020] In the present invention, the thickness of the thin film glass may be 10 to 100 μm.

[0021] In the present invention, the thin film glass may include a flat portion and a curved portion.

[0022] In the present invention, the glass, the first hard coating layer, and the second hard coating layer may be formed in direct contact with each other without including a separate layer.

[0023] The present invention may be applied to a flexible display.

[0024] In addition, the present invention provides an image display device including the optical laminate.

[0025]

[0026] The optical laminate according to the present invention and the image display device including the same form a hard coating layer including an oligomer including a cyclosiloxane group and an alicyclic epoxy group and an epoxy silane coupling agent, thereby improving excellent pressure resistance and adhesion, and further improving anti-fingerprint properties by additionally forming a hard coating layer containing fluorine with low surface energy. Accordingly, the optical laminate is not only particularly suitable for displays using pens, but also has excellent adhesion and bendability, thereby improving device reliability when applied to flexible displays.

[0027] In addition, the optical laminate according to the present invention is formed through direct contact between the glass and the hard coating layer without including a separate substrate between them, so that a process for bonding each substrate layer can be omitted, and thus the manufacturing process can be simplified compared to the conventional one.

[0028]

[0029] FIG. 1 illustrates a laminated structure of an optical laminate according to one embodiment of the present invention.

[0030] In the above drawing, each symbol refers to the following:

[0031] 100: Optical laminate

[0032] 110: Thin film glass

[0033] 120: First hard coating layer

[0034] 130: Second hard coating layer

[0035]

[0036] The present invention relates to an optical laminate comprising a thin film glass, a first hard coating layer formed on one surface of the thin film glass, and a second hard coating layer formed on the first hard coating layer, wherein the first hard coating layer comprises a silicone oligomer and an epoxy silane coupling agent, and the second hard coating layer comprises a photocurable resin, and an image display device comprising the same.

[0037] Hereinafter, preferred embodiments of the present invention will be described in detail. However, these examples are provided solely as examples to more specifically illustrate the present invention, and it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples.

[0038] The terms used herein are for the purpose of describing embodiments and are not intended to limit the present invention. In this specification, singular forms also include plural forms, unless specifically stated otherwise. For example, "hard coating layer" as used herein may refer to at least one of the first hard coating layer and the second hard coating layer.

[0039] 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.

[0040] As used herein, “transparent” means having a visible light transmittance of 70% or more or 80% or more.

[0041] The term 'manufacturing' as used in this specification is a general term for the process of creating a component through a reaction, such as synthesis or polymerization of a compound.

[0042] The term 'forming' used in this specification may be omitted, and the terms 'hard coating forming composition' and 'hard coating composition' have the same meaning.

[0043]

[0044] FIG. 1 illustrates a laminated structure of an optical laminate according to one embodiment of the present invention. As shown in FIG. 1, the optical laminate (100) of the present invention may have a structure including: a thin film glass (110); a first hard coating layer (120) formed on the thin film glass (110); and a second hard coating layer (130) formed on the first hard coating layer, i.e., at the outermost portion.

[0045] The optical laminate of the present invention can have both compression resistance and flexibility for application to a window for a flexible display.

[0046]

[0047] Optical laminate

[0048] The optical laminate of the present invention comprises glass and a hard coating layer, and preferably may comprise a first hard coating layer and a second hard coating layer. More specifically, the first hard coating layer may be formed of a first hard coating composition, and the second hard coating layer may be formed of a second hard coating composition. In addition, the optical laminate of the present invention is an optical laminate comprising: thin film glass; a first hard coating layer formed on one surface of the thin film glass; and a second hard coating layer formed on the first hard coating layer; wherein the first hard coating layer may comprise a silicone oligomer and an epoxy silane coupling agent, and the second hard coating layer may comprise a photocurable resin. In the present invention, the thin film glass, the first hard coating layer, and the second hard coating layer may be formed in direct contact with each other without comprising a separate layer.

[0049]

[0050] Thin film glass (110)

[0051] The above-described thin film glass is intended to replace an existing glass substrate and support a hard coating layer (120, 130) and other substrates or panels, which will be described later, and may include flat and curved portions for the display of an electronic device. The above-described thin film glass may include, for example, flat glass, flexible glass, and curved glass.

[0052] The above-described thin film glass may have the same thickness overall, and according to another embodiment of the present invention, may have flat portions and curved portions with different thicknesses partially at one or more locations as needed. The curved portion refers to a portion that is formed by slimming to a thinner thickness compared to the flat portion, and the curved portion may be an area corresponding to a region where a flexible display is folded in half or a folding portion that is bent in the case of ultra-thin glass (UTG). In this case, the folding portion may include both in-folding and out-folding.

[0053] For example, the thin film glass of the present invention may have different thicknesses for the flat and curved portions, as needed. For example, the thickness of the curved portion may be thinner than that of the flat portion. The curved portion may be located or shaped in a manner recognized in the art as an edge portion, may be one portion or multiple portions, and may be located in the center of the thin film glass.

[0054] When the hard coating layer of the present invention, which will be described later, is applied to thin film glass, the form of the application can be appropriately adjusted depending on the form of the thin film glass. For example, the hard coating layer can be applied with a uniform thickness along the surface of the thin film glass, and the hard coating layer applied on the thin film glass can be partially varied. In particular, when the thickness of the thin film glass is partially different, the hard coating layer applied on the thin film glass can be partially varied so that the optical laminate to which the hard coating layer is applied has an overall flat surface, or the hard coating layer can be applied with a uniform thickness so that the optical laminate has an overall different thickness.

[0055] Specifically, when the optical laminate according to one embodiment of the present invention is applied to a thin film glass including a downwardly concave curved portion, the first hard coating composition applied to one surface of the thin film glass may be applied until a desired first hard coating layer thickness is formed based on the flat portion. Alternatively, the first hard coating composition may be applied with a constant thickness along the curved shape of the thin film glass curved portion, and then the second hard coating composition may be applied until a desired second hard coating layer thickness is formed based on the flat portion. Alternatively, the first hard coating composition may be applied with a constant thickness along the curved shape of the thin film glass curved portion, and then the second hard coating composition may be applied with a constant thickness along the curved shape of the first hard coating layer.

[0056] According to one embodiment of the present invention, any transparent glass can be used as the glass (110), and preferably, silicate glass can be used. The silicate glass is a glass mainly composed of anhydrous silica (silica) that exists naturally in the form of silica sand. The structure of the silicate glass has a very high density and very strong bonds with oxygen and water, so it exhibits low transmittance, making it suitable for use as a display substrate.

[0057]

[0058] In addition, it is preferable that the glass used in the above-mentioned description be thin glass (thin glass, TG) having a thickness of 10 to 300 μm. Unlike existing glass, it is more preferable to have a thickness of 100 μm or less in order to have excellent bending resistance that does not break even when bent or folded for use in a flexible display substrate. Glass thinner than 10 μm has the problem of being easily broken during the manufacturing process.

[0059] The optical laminate according to the present invention may include an additional substrate layer, such as a hard coating layer (120, 130) to be described later, to ensure the durability of the glass (110). Generally, an adhesive layer or a pressure-sensitive adhesive layer is included to form or bond the substrate layer, but the optical laminate according to the present invention is characterized in that it is formed through direct contact without including a separate substrate layer for bonding the hard coating layer, so that the manufacturing process can be simplified compared to a conventional laminate.

[0060]

[0061] Hard coating layer (120, 130)

[0062] The hard coating layer of the present invention may include a first hard coating layer (120) and a second hard coating layer (130), as shown in FIG. 1.

[0063] According to one embodiment of the present invention, the first hard coating layer (120) is characterized by being formed of a first hard coating composition including a silicone oligomer and an epoxy silane coupling agent, and by including the silicone oligomer and the epoxy silane coupling agent, excellent compression resistance and adhesion to glass can be achieved, thereby ensuring bending performance suitable for a flexible display. The second hard coating layer (130) is characterized by being formed of a second hard coating composition including a photocurable resin, and improves the compression resistance, adhesion, scratch resistance, and durability of the optical laminate, and in particular, when further including a fluorine compound having low surface energy, it can improve the fingerprint resistance and readability of the display.

[0064] Referring to Fig. 1, the first hard coating layer (120) is formed on the thin film glass (110), and the second hard coating layer (130) can be formed on the first hard coating layer (120), i.e., on the outermost surface of the optical laminate. The first hard coating layer (120) can secure adhesion between substrates without a separate substrate layer such as an adhesive layer.

[0065] In addition, the optical laminate according to the present invention and the image display device using the same have sufficient flexibility even when a separate protective film is not applied, so that even when pressure is applied to the display surface with a pen, no pen marks are left, and thus the usability of the pen can be greatly improved.

[0066] In addition, the first hard coating composition and the second hard coating composition may each independently further include at least one selected from the group consisting of an additive, an initiator, and a solvent, and the additive may include at least one selected from the group consisting of a silicone-based leveling agent, an ultraviolet stabilizer, a heat stabilizer, and the like. For example, the first hard coating layer may be prepared from a hard coating composition including a silicone oligomer, an epoxy silane coupling agent, a silicone-based leveling agent, an initiator, and a solvent, and the second hard coating layer may be prepared from a hard coating composition including a photocurable resin, a fluorine-based leveling agent, an initiator, and a solvent.

[0067]

[0068] First hard coating layer (120)

[0069] The first hard coating layer of the present invention is formed from a first hard coating composition comprising a silicone oligomer and an epoxy silane coupling agent. The silicone oligomer can be prepared by reacting a siloxane compound containing a cyclosiloxane group with a photopolymerizable compound containing an alicyclic epoxy group in the presence of a catalyst according to a method known in the art.

[0070]

[0071] silicone oligomer

[0072] The above silicone oligomer contains a cyclosiloxane group and an alicyclic substituent, and may form a network structure, and plays a role in significantly improving the flexibility and compression resistance of the first hard coating layer.

[0073] The above silicone oligomer may have a cyclic structure or a network structure having three or four -SiO- units, and may include an organic group represented by -(SiO2R2)- in which Si of the -SiO- unit is independently substituted with an arbitrary substituent R. The R is not particularly limited, but may be an alicyclic substituent described below, or an alkyl group, alkenyl group, or alkynyl group having 1 to 30 carbon atoms.

[0074]

[0075] To prepare a silicone oligomer, one or more cyclosiloxane monomers and a monomer containing an alicyclic substituent may be included, and an appropriate catalyst such as an acidic catalyst or a basic catalyst capable of promoting hydrolysis and condensation reactions may be additionally used. In addition, to promote the reaction, stirring may be performed at 50°C to 120°C for 1 to 120 hours.

[0076] The above cyclosiloxane monomer may have a cyclic structure or a network structure having three or four -SiO- units, and further, the cyclosiloxane monomer may have three or more reactive moieties selected from a carbon-carbon double bond and a thiol. Specifically, since the silicone oligomer contains a cyclosiloxane group, which is a cyclic silicone structure, at its center, it has a flexible structure compared to carbon, thereby having an excellent elastic recovery rate and an effect of improving compression resistance.

[0077] In this regard, in order to form a network structure of the silicone oligomer of the present invention, it is preferable to prepare a trifunctional or higher silicone oligomer having three or more functional groups by bonding multiple, preferably three or more, alicyclic substituents to the cyclosiloxane monomer. In the case of a silicone oligomer having one to two functional groups, it may be difficult to form a network structure. When the number of functional groups is large and the formation of more network structures is possible, it is more preferable in terms of being included in a hard coating composition. The functional group of the present invention may be an epoxy group and / or an oxetane group, but is not limited thereto.

[0078]

[0079] In one embodiment, the cyclosiloxane monomer may include 2,4,6-trivinyl-2,4,6-trimethylcyclotrisiloxane, 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl cyclotetrasiloxane, or a combination thereof. The cyclosiloxane compound may be commercially available or may be synthesized in a known manner. Accordingly, the silicone oligomer may include cyclosiloxane groups derived from 2,4,6-trivinyl-2,4,6-trimethylcyclotrisiloxane and 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl cyclotetrasiloxane.

[0080] The above-mentioned alicyclic substituent may be present at the terminal of the silicone oligomer, and particularly preferably, a compound including an alicyclic epoxy group and / or an oxetane group as a functional group capable of crosslinking with the cyclosiloxane monomer may be mentioned, and any one or a mixture of two or more thereof may be used. Since the hard coating layer including the silicone oligomer of the present invention includes the above-mentioned alicyclic epoxy group and / or oxetane group, warping can be prevented as curing shrinkage is less than that of an acrylic structure. In addition, when an alicyclic epoxy group is included, it is more advantageous in improving adhesion to glass due to the application of an epoxy silane coupling agent.

[0081] As monomers containing the above-mentioned alicyclic epoxy group, examples thereof include 4-vinylcyclohexene dioxide, cyclohexene vinyl monoxide, (3,4-epoxycyclohexyl)methyl 3,4-epoxycyclohexylcarboxylate, 3,4-epoxycyclohexylmethyl methacrylate, 3,4-epoxycyclohexanecarboxylate, 2-(3,4-epoxycyclohexyl)-1,3-dioxolane, or bis(3,4-epoxycyclohexylmethyl)adipate, and any one of these or a mixture of two or more thereof may be used.

[0082] Monomers containing the above oxetane group include 3-methyloxetane, 2-methyloxetane, 3-oxetanol, 2-methyleneoxetane, 3-methyl-3-hydroxymethyloxetane, 3-ethyl-3-hydroxymethyloxetane, 3,3-oxetanedimethanethiol, 2-ethylhexyloxetane, 4-(3-methyloxetan-3-yl)benzonitrile, N-(2,2-dimethylpropyl)-3-methyl-3-oxetanemethanamine, N-(1,2-dimethylbutyl)-3-methyl-3-oxetanemethanamine, xylene bis oxetane, 3-ethyl-3[{(3-ethyloxetan-3-yl)methoxy}methyl]oxetane, (3-ethyloxetan-3-yl)methyl methacrylate, or Examples include 4-[(3-ethyloxetan-3-yl)methoxy]butan-1-ol, and any one of these or a mixture of two or more thereof may be used.

[0083] When the above silicone oligomer contains a cyclosiloxane group and an alicyclic epoxy group and / or an alicyclic oxetane group, bonds between the silicone oligomers occur to form a network structure, thereby expanding the intramolecular spacing by the oligomer compared to an acrylic oligomer, thereby further increasing the flexibility of the cured film.

[0084] Commercially available products include Shin-Etsu's KR-470, OX-SQ TX-100, OX-SQ SI-20, and OX-SQ HDX (Toagosei), and are more desirable in terms of flexibility and compression resistance compared to acrylic oligomers.

[0085] The silicone oligomer is preferably included in an amount of 40 to 70 parts by weight based on the total weight of the first hard coating composition. If it is included in an amount less than 40 parts by weight, the elastic modulus of the coating layer may decrease, causing cracks to easily occur in the coating layer when bent. If it is included in an amount exceeding 70 parts by weight, the viscosity may increase, reducing the applicability and causing problems with the appearance characteristics due to insufficient surface leveling.

[0086]

[0087] Epoxy silane coupling agent

[0088] The above epoxy silane coupling agent refers to a compound having an epoxy group in the organic reactive group of the silane coupling agent. Specifically, R1 x -Si-(OR2) 4-x In the structure, R1 refers to a compound containing an epoxy group. (X is an integer of 1 to 3, and R2 is an alkyl group such as methyl, ethyl, or propyl.) In particular, when the first hard coating composition of the present invention contains an alicyclic epoxy group, adhesion to glass can be secured by including an epoxy silane coupling agent, and when the epoxy silane coupling agent is not included, adhesion between the first hard coating layer and the glass is reduced, which may make the glass vulnerable to impact when folded or bent, and thus cracks, breakage, and delamination may occur, resulting in poor bending properties.

[0089] For example, the epoxy silane coupling agent includes 3-glycidoxypropyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 8-glycidoxyoctyltrimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and the like, and the first hard coating composition may include at least one selected from the group.

[0090] Commercially available products of the above epoxy silane coupling agent include Shin-Etsu's KBM-303, KBM-402, KBM-403, KBM-4803, KBE-402, KBE-403, X-12-981S, X-12-984S, KR-516, and KR-517.

[0091] The above epoxy silane coupling agent may be included preferably in an amount of 0.1 to 30 parts by weight, more preferably 1 to 10 parts by weight, based on 100 parts by weight of the total hard coating composition. By including the epoxy silane coupling agent within the above range, adhesion to glass is improved and flexibility can be provided to the hard coating layer. If it is less than the above range, there is a problem that adhesion to glass is not sufficiently secured, and if it exceeds the above range, there is a concern that optical properties may deteriorate due to scattering due to poor compatibility.

[0092]

[0093] Initiator

[0094] The first hard coating composition of the present invention may further include an initiator. The initiator may be a conventional photoradical polymerization initiator, a photocationic polymerization initiator, or the like. These may be used singly or in combination of two or more. The radical initiator according to one embodiment of the present specification promotes radical polymerization and thereby enhances the curing speed. As the radical initiator, any radical initiator commonly used in the art may be used without limitation.

[0095] For example, one or more selected from the group consisting of hydroxyketones, aminoketones, hydrogen abstraction type photoinitiators, and combinations thereof may be used.

[0096] Specifically, the initiator 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.For example, commercially available products include IRGACURE 184, Darocur 1173, Irgacure 127, Irgacure 2959, Irgacure 500, Irgacure754, Darocur MBF, Lucirin TPO, Lucirin TPO-L, Irgacure 2100, Irgacure 819, and Irgacure from BASF. 819DW, Darocur 4265, Irgacure 2022, Irgacure 784, Irgacure OXE 01, Irgacure OXE 02, Irgacure 907, Irgacure 369, Irgacure 379, Irgacure 389, Darocur BP, Irgacure 651, Irgacure 250, Irgacure 270, etc., ARKLS NCI-831, OPTOMER N-1919, OPTOMER N-1717, etc. of ADEKA, Nanocure BDK, Nanocure EPD, Nanocure BMS, Nanocure ITX, Nanocure A-BCIM, Nanocure BCIM of Daelim Chemical, Micure BK-6, Micure CP-4, Micure HP-8, Micure MS-7, Micure BMS, Micure DETX, Micure PBZ, Micure MBF, Benzoin, etc. of Miwon Specialty Chemical can be used alone or in combination of one or more types. In addition, a substance that can initiate photocuring by generating radicals upon receiving light (such as ultraviolet rays) can be used, for example, triphenylphosphine, but is not limited thereto.

[0097] These photoinitiators are used in an amount of 0.1 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the total composition for forming a hard coating layer. 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.

[0098]

[0099] additives

[0100] In addition, the hard coating composition used to form the first hard coating layer and the second hard coating layer according to the present invention may further include additives such as a leveling agent, an ultraviolet stabilizer, and / or a heat stabilizer.

[0101] Leveling agents are ingredients that provide smoothness and coating properties.

[0102] Leveling agents can be applied using leveling agents commonly used in the industry, such as 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 to these.

[0103] Commercially available products of the above leveling agent include BYK-307, BYK-323, BYK-331, BYK-333, BYK-337, BYK-373, BYK-375, BYK-377, BYK-378, BYK-3530, BYK-3560, BYK-358N, BYK-361N from BYK Chemical; Daegu Corporation's TEGO Glide 410, TEGO Glide 411, TEGO Glide 415, TEGO Glide 420, TEGO Glide 432, TEGO Glide 435, TEGO Glide 440, TEGO Glide 450, TEGO Glide 455, TEGO Rad 2100, TEGO Rad 2200N, TEGO Rad 2250, TEGO Rad 2300, TEGO Rad 2500; 3M Corporation's FC-4430, FC-4432, etc. can be used, but are not limited thereto, and leveling agents commonly used in the art can be applied.

[0104] The leveling agent may be included in an amount of 0.05 to 1 part by weight per 100 parts by weight of the hard coating composition, but is not limited thereto. However, when the leveling agent is included in the hard coating composition within the above range, there is an advantage in that the smoothness and coatability of the coating film are maximized while maintaining excellent pressure resistance and flexibility.

[0105] The above UV stabilizer may be added to protect the coating by blocking or absorbing UV rays, as the surface of the cured coating may decompose due to continuous exposure to UV rays, causing discoloration and crumbling. The above UV stabilizer is classified into absorbers, quenchers, and hindered amine light stabilizers (HALS) according to the mechanism of action. In addition, depending on the chemical structure, it is classified into phenyl salicylate (absorber), benzophenone, etc.

[0106] (Benzophenone, absorbent), benzotriazole (benzotriazole, absorbent), nickel derivative (quencher), and radical scavenger. In the present invention, there is no particular limitation as long as it is a UV stabilizer that does not significantly change the initial color of the coating film.

[0107] As heat stabilizers, for example, commercially applicable products such as polyphenol-based primary heat stabilizers, phosphate-based secondary heat stabilizers, and lactone-based secondary heat stabilizers can be used singly or in combination. These can be used singly or in combination of two or more types. The content can be adjusted appropriately and used, and specifically, it is preferable to include 0.1 to 3 parts by weight based on 100 parts by weight of the hard coating composition of the present invention.

[0108] The above UV stabilizer and heat stabilizer can be used by appropriately adjusting the content at a level that does not affect UV curability.

[0109] The above additives can be added by appropriately adjusting the content within a range that does not impede the effects of the present invention.

[0110]

[0111] solvent

[0112] The solvent included in the hard coating composition used for forming the first hard coating layer and the second hard coating layer according to the present invention 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, and can dissolve or disperse the composition mentioned above.

[0113] 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.

[0114] These solvents are used in an amount of 40 to 98 parts by weight based on 100 parts by weight of the total hard coating composition. If the content of the solvent is less than the above content, the viscosity increases, resulting in poor workability and the thickness of the hard coating layer cannot be reduced, which may result in reduced flexibility. Conversely, if the content exceeds the above range, the desired film thickness cannot be formed, and the coating liquid may flow down during the drying process, contaminating the opposite side of the glass or film and causing stains. Therefore, it is necessary to appropriately adjust the content within the above range.

[0115]

[0116] The hard coating layer may be manufactured using a method known in the art. The thickness of the first hard coating layer may preferably be 10 to 30 μm. Forming the first hard coating layer on one surface of the thin film glass with the first hard coating composition to a thickness within the above range is advantageous in forming a thinner and more flexible display.

[0117]

[0118] Second hard coating layer (130)

[0119] A second hard coating layer having a high water contact angle and excellent durability such as scratch resistance can be laminated on the first hard coating layer having improved adhesion and pressure resistance described above to secure the hardness of the composition and form it more suitable for a display using a pen.

[0120] Specifically, the second hard coating layer of the present invention is formed from a second hard coating composition comprising a photocurable resin. Furthermore, the second hard coating layer further comprises a fluorine compound, thereby imparting fingerprint-resistant properties to the surface of the optical laminate, thereby improving visibility.

[0121]

[0122] photocurable resin

[0123] The second hard coating layer of the present invention may include a photocurable resin and may be formed from a second hard coating composition including the photocurable resin. The photocurable resin is an acrylic polymer, a urethane polymer, an epoxy polymer, a silicon polymer, or a silica compound, which is used as a binder in the form of a monomer or oligomer, and a photoinitiator and additives are added to the composition, thereby providing hard coating properties by curing the composition through irradiation with light such as ultraviolet rays.

[0124] In the present invention, “(meth)acryl-” refers to “methacryl-”, “acryl-” or both.

[0125]

[0126] The (meth)acrylate oligomer according to the present invention is not particularly limited, and may include polyester acrylate, urethane acrylate, epoxy acrylate, polyether acrylate, etc., and preferably, a urethane acrylate oligomer can be used. Hereinafter, the case of a urethane acrylate oligomer will be specifically described, but is not limited thereto. The urethane acrylate oligomer according to the present invention may have 2 to 15 functional groups. If the number of functional groups is less than 2, the improvement in hardness and scratch resistance may be minimal, and if the number of functional groups is more than 15, the hardness may be excellent, but the viscosity may increase. The urethane (meth)acrylate oligomer can be used without limitation as one used in the relevant field.

[0127] The content of the photocurable resin is not particularly limited, but may be included in an amount of, for example, 10 to 50 parts by weight, and preferably 30 to 50 parts by weight, based on a total of 100 parts by weight of the second hard coating composition. When the above range is satisfied, durability such as scratch resistance can be secured while also implementing curl characteristics and flexibility. When it is less than 10 parts by weight, flexibility may be reduced, and when it exceeds 50 parts by weight, it is difficult to secure hardness suitable for a display due to the presence of unreacted functional groups due to the steric inhibition effect.

[0128] In particular, when a dendrimer compound is further included in the photocurable resin of the second hard coating composition, it is particularly preferable because the flexibility and hardness of the hard coating film or hard coating layer can be further improved. An appropriate curing density can be achieved, and thus, the hardness of the hard coating layer can be secured while significantly improving the adhesion and scratch resistance. The dendrimer compound is not particularly limited, but is preferably included in an amount of 1 to 10 parts by weight based on 100 parts by weight of the entire second hard coating composition.

[0129] In the present application, a dendrimer compound may refer to a compound in which molecular chains are regularly polymerized from the center outward. Meanwhile, the "generation" of a dendrimer compound refers to a stage in which the dendrimer structure grows, and it is understood that one generation increases each time a unit structure that is regularly repeated based on the center of the molecule is added. For example, when the formed first-generation molecular terminal undergoes a polymerization reaction again, it becomes the second generation, and a repetitive polymerization reaction proceeds. According to embodiments of the present invention, the dendrimer compound may have a plurality of (meth)acrylate terminal groups and may have a structure of two or more generations.

[0130]

[0131] Leveling agent

[0132] The leveling agent may include at least one selected from the group consisting of a silicone-based leveling agent, a fluorine-based leveling agent, and an acrylic-based leveling agent. When the leveling agent is included in the hard coating composition, there is an advantage in that smoothness and coatability can be imparted when forming a coating film. In particular, the second hard coating layer of the present invention may include a fluorine-based leveling agent. When a fluorine-based leveling agent with low surface energy is used, it is particularly preferable in terms of improving fingerprint resistance.

[0133] The leveling agent containing a fluorine-based UV-curable functional group is a component that provides antifouling properties, wear resistance, and chemical resistance, and must contain a fluorine component. In addition, it is not particularly limited as long as it has a UV-curable functional group and can chemically bond to the monomer or oligomer layer forming the hard coating layer.

[0134] Specifically, (meth)acrylate containing a perfluoroalkyl group, (meth)acrylate containing a perfluoroaliphatic group, (meth)acrylate containing a perfluoroaromatic group, etc. can be used. At this time, the fluorine-based UV-curable functional group-containing compound preferably has 1 to 6 UV-curable functional groups, and is preferably included in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the composition for forming the second hard coating layer. When the fluorine-based leveling agent having the above compound is included in the above range, there is an advantage in that anti-fingerprint properties and coatability can be maximized while maintaining excellent hardness and flexibility. If it is less than 0.01 parts by weight, it is difficult to sufficiently secure wear resistance and antifouling properties, and if it exceeds 10 parts by weight, the film hardness and scratch properties may deteriorate.

[0135] Commercially available products include Daikin's DAC-HP, but are not limited thereto, and leveling agents commonly used in the industry can be applied.

[0136]

[0137] Initiator

[0138] The second hard coating composition of the present invention may further include an initiator. The initiator that may be included in the second hard coating composition is the same as that included in the first hard coating composition, and thus is omitted.

[0139] The above initiator is used in an amount of 0.1 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the entire second hard coating composition. If the content is less than the above range, the curing speed of the composition is slow and under-curing occurs, resulting in poor mechanical properties. Conversely, if the content exceeds the above range, cracks may occur in the coating film due to over-curing.

[0140] Additives and solvents

[0141] Additives and solvents that may be further included in the second hard coating layer composition are the same as those that may be further included in the first hard coating layer described above, and therefore will be omitted.

[0142]

[0143] The hard coating layer may be manufactured using a method known in the art. The thickness of the second hard coating layer may preferably be 10 to 30 μm. Forming a second hard coating layer on one surface of the thin film glass with the second hard coating composition to a thickness within the above range is advantageous in forming a thinner display.

[0144] An optical laminate according to an embodiment of the present invention may be formed by coating a first hard coating composition on glass (110) and performing drying and UV curing steps to form a first hard coating layer (120), and then coating a second hard coating composition on the first hard coating layer (120) and then performing drying and UV curing steps in the same manner as the first hard coating layer to form a second hard coating layer (130).

[0145] The step of drying the optical laminate 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.

[0146] The step of curing the optical laminate is 50 to 1000 mJ / cm 2 , preferably 200 to 800 mJ / cm 2 irradiate with active rays such as UV rays. In particular, the step of forming the first hard coating layer (120) is irradiated with 50 to 600 mJ / cm 2 The first hardening is performed weakly at a level of 300 to 800 mJ / cm, and the step of forming the second hard coating layer (130) is performed at a level of 300 to 800 mJ / cm. 2By irradiating with strong UV light, the adhesion between the second hard coating layer and the first hard coating layer can be further strengthened. Light sources used for irradiation include low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, and argon gas lasers, and in some cases, X-rays and electron beams can also be used.

[0147]

[0148] <Image display device>

[0149] Embodiments of the present invention provide an image display device including the optical laminate described above.

[0150] For example, the optical laminate described above may be inserted into an image display device and included together with a polarizing layer or a touch sensor layer.

[0151] 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, and a field emission display device, and may be a flexible display device having pressure resistance, anti-fouling properties, flexibility, and bending properties.

[0152] In this case, the optical laminate according to embodiments of the present invention can be more effectively applied as a window or window laminate of a flexible display device. As the adhesion between the glass and the hard coating layer included in the optical laminate according to embodiments of the present invention increases, the bendability improves, and the flexibility and durability of the window can be improved together. Accordingly, for example, the impact resistance and compression resistance of the flexible display device can be improved, and damage such as cracks and peeling can be prevented even when bending.

[0153]

[0154] Hereinafter, specific embodiments of the present invention will be described. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Unless otherwise specified, "%" and "part" are mass% and mass parts, respectively.

[0155]

[0156] Manufacturing example: Manufacturing of hard coating composition

[0157] Manufacturing Example 1

[0158] A hard coating composition was prepared by mixing 47.9 parts by weight of a silicone oligomer containing an alicyclic epoxy (Shin-Etsu, KR-470), 1 part by weight of an epoxy silane coupling agent (Shin-Etsu, KBM-403), 50 parts by weight of propylene glycol monomethyl ether, 1 part by weight of an initiator (Irgacure 250), and 0.1 part by weight of a silicone leveling agent (BYK, BYK-307) using a stirrer and filtering using a PP filter.

[0159] Manufacturing Example 2

[0160] A hard coating composition was prepared by mixing 48.9 parts by weight of a silicone oligomer (Shin-Etsu, KR-470) containing an alicyclic epoxy, 50 parts by weight of propylene glycol monomethyl ether, 1 part by weight of an initiator (Irgacure 250), and 0.1 part by weight of a silicone leveling agent (BYK, BYK-307) using a stirrer and filtering using a PP filter.

[0161] Manufacturing Example 3

[0162] A hard coating composition was prepared by mixing 64 parts by weight of urethane acrylate oligomer (Mitsubishi Chemical, UT-5181), 3 parts by weight of acrylic silane coupling agent (Shin-Etsu, KBM-503), 31.6 parts by weight of methyl ethyl ketone, 1.2 parts by weight of photoradical initiator (1-hydroxycyclohexyl phenyl ketone), and 0.2 parts by weight of silicone leveling agent (BYK, BYK-307) using a stirrer and filtering using a PP material filter.

[0163] Manufacturing Example 4

[0164] 5 parts by weight of dendrimer acrylate (Miwon Specialty Chemical, SP1106), 42 parts by weight of hexafunctional acrylate (Miwon Specialty Chemical, Miramer M600), 50 parts by weight of methyl ethyl ketone, 1.5 parts by weight of 1-hydroxycyclohexyl phenyl ketone, and 1.5 parts by weight of fluorinated leveling agent (DAC-HP, Daikin) were mixed using a stirrer and filtered using a PP material filter to prepare a hard coating composition.

[0165] Manufacturing Example 5

[0166] 47.9 parts by weight of urethane acrylate oligomer (Mitsubishi Chemical, UT-5181), 1 part by weight of epoxy silane coupling agent (Shin-Etsu, KBM-403), 50 parts by weight of propylene glycol monomethyl ether, 1 part by weight of initiator (Irgacure 250), and 0.1 part by weight of silicone leveling agent (BYK, BYK-307) were mixed using a stirrer and filtered using a PP material filter to prepare a hard coating composition.

[0167]

[0168] Examples and Comparative Examples: Manufacturing of Optical Laminates

[0169] An optical laminate was manufactured according to the examples and comparative examples, and the thickness of the hard coating layer was laminated as shown in Table 1 below.

[0170]

[0171] Example 1

[0172] The hard coating composition of the above manufacturing example 1 was coated on a thin film glass (90 ㎛) to a thickness of 15 ㎛, and the solvent was dried and UV accumulated light intensity was 1000 mJ / cm in a nitrogen atmosphere. 2 A hard coating was manufactured by investigating, and the AFHC layer solution of the above manufacturing example 4 was coated on it to a thickness of 15 ㎛, and the solvent was dried and UV accumulated light intensity was 500 mJ / cm in a nitrogen atmosphere. 2 An optical laminate is manufactured by investigating the .

[0173] Example 2

[0174] The hard coating composition of the above manufacturing example 1 was coated on a thin film glass (90 ㎛) to a thickness of 25 ㎛, and the solvent was dried and UV accumulated light intensity was 1000 mJ / cm in a nitrogen atmosphere. 2 A hard coating was manufactured by investigating, and the AFHC layer solution of the above manufacturing example 4 was coated on it to a thickness of 20 ㎛, and the solvent was dried and UV accumulated light intensity was 500 mJ / cm in a nitrogen atmosphere. 2 An optical laminate is manufactured by investigating the .

[0175] Example 3

[0176] An optical laminate was manufactured in the same manner as Example 1, except that the coating composition was applied thickly to the curved portion (50 μm) and thinly to the flat portion, so that the optical laminate having the hard coating layer applied had an overall flat surface, for a thin film glass made by the technique known in prior art patent 10-2272926.

[0177] Comparative Example 1

[0178] The hard coating composition of the above manufacturing example 2 was coated on a thin film glass (90 ㎛) to a thickness of 15 ㎛, and the solvent was dried and UV accumulated light was 1000 mJ / cm in a nitrogen atmosphere. 2 A hard coating was manufactured by investigating, and the AFHC layer solution of the above manufacturing example 4 was coated on it to a thickness of 15 ㎛, and the solvent was dried and UV accumulated light intensity was 500 mJ / cm in a nitrogen atmosphere. 2It is manufactured by investigating.

[0179] Comparative Example 2

[0180] The hard coating composition of the above manufacturing example 3 was coated on a thin film glass (90 ㎛) to a thickness of 15 ㎛, and the solvent was dried and UV accumulated light was 1000 mJ / cm in a nitrogen atmosphere. 2 A hard coating was manufactured by investigating, and the AFHC layer solution of the above manufacturing example 4 was coated on it to a thickness of 15 ㎛, and the solvent was dried and UV accumulated light intensity was 500 mJ / cm in a nitrogen atmosphere. 2 It is manufactured by investigating.

[0181] Comparative Example 3

[0182] The hard coating composition of the above manufacturing example 5 was coated on a thin film glass (90 ㎛) to a thickness of 15 ㎛, and the solvent was dried and UV accumulated light was 1000 mJ / cm in a nitrogen atmosphere. 2 A hard coating was manufactured by investigating, and the AFHC layer solution of the above manufacturing example 4 was coated on it to a thickness of 15 ㎛, and the solvent was dried and UV accumulated light intensity was 500 mJ / cm in a nitrogen atmosphere. 2 It is manufactured by investigating.

[0183] Comparative Example 4

[0184] The hard coating composition of the above manufacturing example 1 was coated on a thin film glass (90 ㎛) to a thickness of 15 ㎛, and the solvent was dried and UV accumulated light intensity was 1000 mJ / cm in a nitrogen atmosphere. 2 A hard coating is manufactured by investigating.

[0185] Thin film glass thickness 1st hard coating layer thickness 2nd hard coating layer thickness Example 1901515 Example 2902520 Example 3 Flat part 100 Curved part 501515 Comparative example 1901515 Comparative example 2901515 Comparative example 3901515 Comparative example 49015X

[0186] (Unit: ㎛)

[0187] Experimental example

[0188] The physical properties of the optical laminates manufactured in Examples 1 to 3 and Comparative Examples 1 to 4 were measured by the following method, and the results are shown in Table 2.

[0189]

[0190] (1) Initial water contact angle evaluation

[0191] After dropping 2 μl of a liquid droplet at room temperature (25°C) on the hard coating layer of the optical laminate manufactured in the above examples and comparative examples, the water contact angle was measured using a contact angle measuring device DSA100 from KRUSS.

[0192]

[0193] (2) Permeability evaluation

[0194] The transmittance of the optical laminates of the above examples and comparative examples was measured using a Murakami Corporation haze meter HM-150N.

[0195]

[0196] (3) Haze evaluation

[0197] The haze of the optical laminates of the above examples and comparative examples was measured using a Murakami haze meter HM-150N.

[0198]

[0199] (4) Evaluation of pressure resistance

[0200] After fixing the optical laminate manufactured above with tape, the surface pressing performance was evaluated by mounting a circular probe with a diameter of 0.7 mm using a Texture Analyser (TA.XT.Plus C) from Stable Micro Systems.

[0201] Using a 0.7 mm circular probe, the hard coat surface was pressed for 10 seconds from 0.5 kg to 5 kg in 0.5 kg increments, and the glass coating product was left at 25°C and 50% humidity, and the presence or absence of the pressed area was checked after 24 hours.

[0202]

[0203] Poetry under 1kg: X

[0204] 2kg~3kg Poet: △

[0205] 3kg or more: ○

[0206]

[0207] (5) Adhesion evaluation

[0208] The optical laminates of the above examples and comparative examples were bonded to glass using a transparent adhesive so that the second hard coating layer was on the surface, and scratches were made on the hard coating surface in the shape of 100 squares in length and width at 1 mm intervals using a cutter knife, and then an adhesion test was performed three times using a niche tape.

[0209] <Evaluation Criteria>

[0210] 5B: Unpeeled

[0211] 4B: Less than 5% peeling

[0212] 3B: 5~15% peeling

[0213] 2B: 15~35% peeling

[0214] 1B: 35~65% peeling

[0215] 0B: 65% or more peeling

[0216]

[0217] 1B and below: X

[0218] 2B or higher but less than 4B: △

[0219] 4B and above: ○

[0220]

[0221] (6) Scratch resistance evaluation

[0222] The second hard coating layer of the optical laminate manufactured above was fixed with tape so that it was on the surface, and a scratch resistance test was performed 500 times back and forth under a load of 500 g using steel wool #0000 on a steel wool tester (WT-LCM100, Korea Protec Co.).

[0223] Poet with 5 or more scratches: X

[0224] Less than 5 scratches: ○

[0225]

[0226] (7) Flexibility evaluation

[0227] The hard coating film manufactured above was folded so that the second hard coating layers were in contact with each other and the radius of curvature of the folded portion was 5 mm, and then stored in a high temperature (60°C) and high humidity (90%) environment, and a folding test was conducted to check the appearance after 240 hours.

[0228] <Evaluation Criteria>

[0229] ○: No cracks, breakage, or delamination

[0230] X: Cracks, fractures, or delamination occur

[0231]

[0232] Thin film glass thickness [㎛]Water contact angleTransmittance [%]Haze [%]Indentation resistanceScratch resistanceAdhesionFlexibilityExample 190113°91.20.2OOOOExample 290111°91.00.3OOOOExample 3Flat part 100Bent part 50113°91.10.1OOOOComparative example 190112°91.60.2△OXXComparative example 290111°91.40.2XOOOComparative example 390113°91.20.2XOXXComparative example 490NG91.20.2OXOO

[0233]

[0234] Referring to the experimental data in Table 2 above, in the case of Examples 1 to 3 in which the optical laminate including the first hard coating layer and the second hard coating layer according to the present invention was applied, not only did the basic performances for the display, such as transmittance and haze, meet the requirements, but also showed excellent results in evaluations of pressure resistance, water contact angle, scratch resistance, adhesion, and bendability.

[0235] On the other hand, in the case of Comparative Example 1, some pressure marks were observed in the pressure resistance evaluation, and the adhesiveness was particularly deteriorated due to the lack of an epoxy silane coupling agent. Accordingly, it was vulnerable to cracking, breakage, and delamination when folded or bent, and showed poor results in the bending resistance evaluation.

[0236] Additionally, in the case of Comparative Example 2, the first hard coating composition did not contain the silicone oligomer of the present invention but contained an acrylic coupling agent, and it was confirmed that in this case, the pressing properties were not improved at all.

[0237] In addition, in the case of Comparative Example 3, the first hard coating composition did not contain the silicone oligomer of the present invention, so the compression resistance was poor, and since it contained an oligomer that did not contain an epoxy group and an epoxy silane coupling agent, the adhesion was also reduced, so that breakage and delamination occurred and the bending property was poor.

[0238] In addition, in the case of Comparative Example 4, poor results were shown in the water contact angle and scratch resistance evaluations because a suitable second hard coating layer was not included to supplement the first hard coating layer.

[0239]

[0240] The optical laminate according to the present invention and the image display device including the same form a hard coating layer including an oligomer including a cyclosiloxane group and an alicyclic epoxy group and an epoxy silane coupling agent, thereby improving excellent pressure resistance and adhesion, and further improving anti-fingerprint properties by additionally forming a hard coating layer containing fluorine with low surface energy. Accordingly, the optical laminate is not only particularly suitable for displays using pens, but also has excellent adhesion and bendability, thereby improving device reliability when applied to flexible displays.

Claims

1. Thin film glass; A first hard coating layer formed on one surface of the thin film glass; and An optical laminate comprising a second hard coating layer formed on a first hard coating layer; The above first hard coating layer includes a silicone oligomer and an epoxy silane coupling agent, An optical laminate, characterized in that the second hard coating layer comprises a photocurable resin.

2. In claim 1, An optical laminate, characterized in that the above silicone oligomer comprises a cyclosiloxane group and an alicyclic substituent.

3. In claim 2, An optical laminate, characterized in that the above-mentioned alicyclic substituent is at least one of an alicyclic epoxy group and an oxetane group.

4. In claim 1, An optical laminate, characterized in that the above silicone oligomer includes an organic group represented by -(SiO2R2)-, wherein R is an alicyclic substituent, an alkyl group having 1 to 30 carbon atoms, an alkenyl group, or an alkynyl group.

5. In claim 1, An optical laminate, characterized in that the silicone oligomer comprises a cyclosiloxane group derived from 2,4,6-trivinyl-2,4,6-trimethylcyclotrisiloxane and 2,4,6,8-tetramethyl-2,4,6,8-tetravinyl cyclotetrasiloxane.

6. In claim 1, An optical laminate, wherein the epoxy silane coupling agent comprises at least one selected from 3-glycidoxypropyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 8-glycidoxyoctyltrimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

7. In claim 1, An optical laminate in which the photocurable resin of the second hard coating layer comprises a urethane (meth)acrylate oligomer.

8. In claim 1, An optical laminate, wherein the second hard coating layer comprises a fluorine-based leveling agent.

9. In claim 8, An optical laminate, wherein the fluorine-based leveling agent comprises at least one selected from the group consisting of a (meth)acrylate containing a perfluoroalkyl group, a (meth)acrylate containing a perfluoroaliphatic group, and a (meth)acrylate containing a perfluoroaromatic group.

10. In claim 1, The second hard coating layer is manufactured using a composition for forming a second hard coating layer, An optical laminate comprising 0.01 to 10 parts by weight of a fluorine-based leveling agent relative to 100 parts by weight of the total composition for forming the second hard coating layer.

11. In claim 1, The thickness of the above first hard coating layer is 10㎛ or more and 30㎛ or less, An optical laminate, wherein the thickness of the second hard coating layer is 10 ㎛ or more and 30 ㎛ or less.

12. In claim 1, An optical laminate wherein the thickness of the above thin film glass is 10 to 100 μm.

13. In claim 1, An optical laminate, wherein the above thin film glass includes a flat portion and a curved portion.

14. In claim 1, An optical laminate, characterized in that the glass, the first hard coating layer, and the second hard coating layer are formed in direct contact with each other without including a separate layer.

15. In claim 1, An optical laminate for application to flexible displays.

16. An image display device comprising an optical laminate according to any one of claims 1 to 15.

Images